alternative to assert

[gtkD.git] / src / cairoLib / Cairo.d

/*
 * This file is part of duit.
 *
 * duit is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * duit is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with duit; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
 
// generated automatically - do not change
// find conversion definition on APILookup.txt
// implement new conversion functionalities on the wrap.utils pakage

/*
 * Conversion parameters:
 * inFile  = cairo-cairo-t.html
 * outPack = cairoLib
 * outFile = Cairo
 * strct   = cairo_t
 * realStrct=
 * ctorStrct=
 * clss    = Cairo
 * interf  = 
 * class Code: No
 * interface Code: No
 * template for:
 * extend  = 
 * implements:
 * prefixes:
 *      - cairo_
 * omit structs:
 * omit prefixes:
 * omit code:
 * imports:
 *      - cairoLib.Surface
 *      - glib.Str
 * structWrap:
 *      - cairo_surface_t* -> Surface
 *      - cairo_t* -> Cairo
 * local aliases:
 */

module cairoLib.Cairo;

private import cairoLib.cairoLibtypes;

private import lib.cairoLib;

private import cairoLib.Surface;
private import glib.Str;

/**
 * Description
 *  cairo_t is the main object used when drawing with cairo. To
 *  draw with cairo, you create a cairo_t, set the target surface,
 *  and drawing options for the cairo_t, create shapes with
 *  functions like cairo_move_to() and cairo_line_to(), and then
 *  draw shapes with cairo_stroke() or cairo_fill().
 *  cairo_t's can be pushed to a stack via cairo_save().
 *  They may then safely be changed, without loosing the current state.
 *  Use cairo_restore() to restore to the saved state.
 */
public class Cairo
{
        
        /** the main Gtk struct */
        protected cairo_t* cairo;
        
        
        public cairo_t* getCairoStruct()
        {
                return cairo;
        }
        
        
        /** the main Gtk struct as a void* */
        protected void* getStruct()
        {
                return cast(void*)cairo;
        }
        
        /**
         * Sets our main struct and passes it to the parent class
         */
        public this (cairo_t* cairo)
        {
                this.cairo = cairo;
        }
        
        /**
         * Description
         */
        
        /**
         * Description
         */
        
        /**
         * Description
         */
        
        
        /**
         * Creates a new cairo_t with all graphics state parameters set to
         * default values and with target as a target surface. The target
         * surface should be constructed with a backend-specific function such
         * as cairo_image_surface_create() (or any other
         * cairo_<backend>_surface_create variant).
         * This function references target, so you can immediately
         * call cairo_surface_destroy() on it if you don't need to
         * maintain a separate reference to it.
         * target:
         *  target surface for the context
         * Returns:
         *  a newly allocated cairo_t with a reference
         *  count of 1. The initial reference count should be released
         *  with cairo_destroy() when you are done using the cairo_t.
         *  This function never returns NULL. If memory cannot be
         *  allocated, a special cairo_t object will be returned on
         *  which cairo_status() returns CAIRO_STATUS_NO_MEMORY.
         *  You can use this object normally, but no drawing will
         *  be done.
         */
        public static Cairo create(Surface target)
        {
                // cairo_t* cairo_create (cairo_surface_t *target);
                return new Cairo( cairo_create((target is null) ? null : target.getSurfaceStruct()) );
        }
        
        /**
         * Increases the reference count on cr by one. This prevents
         * cr from being destroyed until a matching call to cairo_destroy()
         * is made.
         * cr:
         *  a cairo_t
         * Returns:
         *  the referenced cairo_t.
         */
        public Cairo reference()
        {
                // cairo_t* cairo_reference (cairo_t *cr);
                return new Cairo( cairo_reference(cairo) );
        }
        
        /**
         * Decreases the reference count on cr by one. If the result
         * is zero, then cr and all associated resources are freed.
         * See cairo_reference().
         * cr:
         *  a cairo_t
         */
        public void destroy()
        {
                // void cairo_destroy (cairo_t *cr);
                cairo_destroy(cairo);
        }
        
        /**
         * Checks whether an error has previously occurred for this context.
         * cr:
         *  a cairo context
         * Returns:
         * the current status of this context, see cairo_status_t
         */
        public cairo_status_t status()
        {
                // cairo_status_t cairo_status (cairo_t *cr);
                return cairo_status(cairo);
        }
        
        /**
         * Makes a copy of the current state of cr and saves it
         * on an internal stack of saved states for cr. When
         * cairo_restore() is called, cr will be restored to
         * the saved state. Multiple calls to cairo_save() and
         * cairo_restore() can be nested; each call to cairo_restore()
         * restores the state from the matching paired cairo_save().
         * It isn't necessary to clear all saved states before
         * a cairo_t is freed. If the reference count of a cairo_t
         * drops to zero in response to a call to cairo_destroy(),
         * any saved states will be freed along with the cairo_t.
         * cr:
         *  a cairo_t
         */
        public void save()
        {
                // void cairo_save (cairo_t *cr);
                cairo_save(cairo);
        }
        
        /**
         * Restores cr to the state saved by a preceding call to
         * cairo_save() and removes that state from the stack of
         * saved states.
         * cr:
         *  a cairo_t
         */
        public void restore()
        {
                // void cairo_restore (cairo_t *cr);
                cairo_restore(cairo);
        }
        
        /**
         * Gets the target surface for the cairo context as passed to
         * cairo_create().
         * This function will always return a valid pointer, but the result
         * can be a "nil" surface if cr is already in an error state,
         * (ie. cairo_status() != CAIRO_STATUS_SUCCESS).
         * A nil surface is indicated by cairo_surface_status()
         * != CAIRO_STATUS_SUCCESS.
         * cr:
         *  a cairo context
         * Returns:
         *  the target surface. This object is owned by cairo. To
         * keep a reference to it, you must call cairo_surface_reference().
         */
        public Surface getTarget()
        {
                // cairo_surface_t* cairo_get_target (cairo_t *cr);
                return new Surface( cairo_get_target(cairo) );
        }
        
        /**
         * Temporarily redirects drawing to an intermediate surface known as a
         * group. The redirection lasts until the group is completed by a call
         * to cairo_pop_group() or cairo_pop_group_to_source(). These calls
         * provide the result of any drawing to the group as a pattern,
         * (either as an explicit object, or set as the source pattern).
         * This group functionality can be convenient for performing
         * intermediate compositing. One common use of a group is to render
         * objects as opaque within the group, (so that they occlude each
         * other), and then blend the result with translucence onto the
         * destination.
         * Groups can be nested arbitrarily deep by making balanced calls to
         * cairo_push_group()/cairo_pop_group(). Each call pushes/pops the new
         * target group onto/from a stack.
         * The cairo_push_group() function calls cairo_save() so that any
         * changes to the graphics state will not be visible outside the
         * group, (the pop_group functions call cairo_restore()).
         * By default the intermediate group will have a content type of
         * CAIRO_CONTENT_COLOR_ALPHA. Other content types can be chosen for
         * the group by using cairo_push_group_with_content() instead.
         * As an example, here is how one might fill and stroke a path with
         * translucence, but without any portion of the fill being visible
         * under the stroke:
         * cairo_push_group (cr);
         * cairo_set_source (cr, fill_pattern);
         * cairo_fill_preserve (cr);
         * cairo_set_source (cr, stroke_pattern);
         * cairo_stroke (cr);
         * cairo_pop_group_to_source (cr);
         * cairo_paint_with_alpha (cr, alpha);
         * cr:
         *  a cairo context
         * Since 1.2
         */
        public void pushGroup()
        {
                // void cairo_push_group (cairo_t *cr);
                cairo_push_group(cairo);
        }
        
        /**
         * Temporarily redirects drawing to an intermediate surface known as a
         * group. The redirection lasts until the group is completed by a call
         * to cairo_pop_group() or cairo_pop_group_to_source(). These calls
         * provide the result of any drawing to the group as a pattern,
         * (either as an explicit object, or set as the source pattern).
         * The group will have a content type of content. The ability to
         * control this content type is the only distinction between this
         * function and cairo_push_group() which you should see for a more
         * detailed description of group rendering.
         * cr:
         *  a cairo context
         * content:
         *  a cairo_content_t indicating the type of group that
         *  will be created
         * Since 1.2
         */
        public void pushGroupWithContent(cairo_content_t content)
        {
                // void cairo_push_group_with_content (cairo_t *cr,  cairo_content_t content);
                cairo_push_group_with_content(cairo, content);
        }
        
        /**
         * Terminates the redirection begun by a call to cairo_push_group() or
         * cairo_push_group_with_content() and returns a new pattern
         * containing the results of all drawing operations performed to the
         * group.
         * The cairo_pop_group() function calls cairo_restore(), (balancing a
         * call to cairo_save() by the push_group function), so that any
         * changes to the graphics state will not be visible outside the
         * group.
         * cr:
         *  a cairo context
         * Returns:
         *  a newly created (surface) pattern containing the
         * results of all drawing operations performed to the group. The
         * caller owns the returned object and should call
         * cairo_pattern_destroy() when finished with it.
         * Since 1.2
         */
        public cairo_pattern_t* popGroup()
        {
                // cairo_pattern_t* cairo_pop_group (cairo_t *cr);
                return cairo_pop_group(cairo);
        }
        
        /**
         * Terminates the redirection begun by a call to cairo_push_group() or
         * cairo_push_group_with_content() and installs the resulting pattern
         * as the source pattern in the given cairo context.
         * The behavior of this function is equivalent to the sequence of
         * operations:
         * cairo_pattern_t *group = cairo_pop_group (cr);
         * cairo_set_source (cr, group);
         * cairo_pattern_destroy (group);
         * but is more convenient as their is no need for a variable to store
         * the short-lived pointer to the pattern.
         * The cairo_pop_group() function calls cairo_restore(), (balancing a
         * call to cairo_save() by the push_group function), so that any
         * changes to the graphics state will not be visible outside the
         * group.
         * cr:
         *  a cairo context
         * Since 1.2
         */
        public void popGroupToSource()
        {
                // void cairo_pop_group_to_source (cairo_t *cr);
                cairo_pop_group_to_source(cairo);
        }
        
        /**
         * Gets the target surface for the current group as started by the
         * most recent call to cairo_push_group() or
         * cairo_push_group_with_content().
         * This function will return NULL if called "outside" of any group
         * rendering blocks, (that is, after the last balancing call to
         * cairo_pop_group() or cairo_pop_group_to_source()).
         * cr:
         *  a cairo context
         * Returns:
         *  the target group surface, or NULL if none. This
         * object is owned by cairo. To keep a reference to it, you must call
         * cairo_surface_reference().
         * Since 1.2
         */
        public Surface getGroupTarget()
        {
                // cairo_surface_t* cairo_get_group_target (cairo_t *cr);
                return new Surface( cairo_get_group_target(cairo) );
        }
        
        /**
         * Sets the source pattern within cr to an opaque color. This opaque
         * color will then be used for any subsequent drawing operation until
         * a new source pattern is set.
         * The color components are floating point numbers in the range 0 to
         * 1. If the values passed in are outside that range, they will be
         * clamped.
         * cr:
         *  a cairo context
         * red:
         *  red component of color
         * green:
         *  green component of color
         * blue:
         *  blue component of color
         */
        public void setSourceRgb(double red, double green, double blue)
        {
                // void cairo_set_source_rgb (cairo_t *cr,  double red,  double green,  double blue);
                cairo_set_source_rgb(cairo, red, green, blue);
        }
        
        /**
         * Sets the source pattern within cr to a translucent color. This
         * color will then be used for any subsequent drawing operation until
         * a new source pattern is set.
         * The color and alpha components are floating point numbers in the
         * range 0 to 1. If the values passed in are outside that range, they
         * will be clamped.
         * cr:
         *  a cairo context
         * red:
         *  red component of color
         * green:
         *  green component of color
         * blue:
         *  blue component of color
         * alpha:
         *  alpha component of color
         */
        public void setSourceRgba(double red, double green, double blue, double alpha)
        {
                // void cairo_set_source_rgba (cairo_t *cr,  double red,  double green,  double blue,  double alpha);
                cairo_set_source_rgba(cairo, red, green, blue, alpha);
        }
        
        /**
         * Sets the source pattern within cr to source. This pattern
         * will then be used for any subsequent drawing operation until a new
         * source pattern is set.
         * Note: The pattern's transformation matrix will be locked to the
         * user space in effect at the time of cairo_set_source(). This means
         * that further modifications of the current transformation matrix
         * will not affect the source pattern. See cairo_pattern_set_matrix().
         * XXX: I'd also like to direct the reader's attention to some
         * (not-yet-written) section on cairo's imaging model. How would I do
         * that if such a section existed? (cworth).
         * cr:
         *  a cairo context
         * source:
         *  a cairo_pattern_t to be used as the source for
         * subsequent drawing operations.
         */
        public void setSource(cairo_pattern_t* source)
        {
                // void cairo_set_source (cairo_t *cr,  cairo_pattern_t *source);
                cairo_set_source(cairo, source);
        }
        
        /**
         * This is a convenience function for creating a pattern from surface
         * and setting it as the source in cr with cairo_set_source().
         * The x and y parameters give the user-space coordinate at which
         * the surface origin should appear. (The surface origin is its
         * upper-left corner before any transformation has been applied.) The
         * x and y patterns are negated and then set as translation values
         * in the pattern matrix.
         * Other than the initial translation pattern matrix, as described
         * above, all other pattern attributes, (such as its extend mode), are
         * set to the default values as in cairo_pattern_create_for_surface().
         * The resulting pattern can be queried with cairo_get_source() so
         * that these attributes can be modified if desired, (eg. to create a
         * repeating pattern with cairo_pattern_set_extend()).
         * cr:
         *  a cairo context
         * surface:
         *  a surface to be used to set the source pattern
         * x:
         *  User-space X coordinate for surface origin
         * y:
         *  User-space Y coordinate for surface origin
         */
        public void setSourceSurface(Surface surface, double x, double y)
        {
                // void cairo_set_source_surface (cairo_t *cr,  cairo_surface_t *surface,  double x,  double y);
                cairo_set_source_surface(cairo, (surface is null) ? null : surface.getSurfaceStruct(), x, y);
        }
        
        /**
         * Gets the current source pattern for cr.
         * cr:
         *  a cairo context
         * Returns:
         *  the current source pattern. This object is owned by
         * cairo. To keep a reference to it, you must call
         * cairo_pattern_reference().
         */
        public cairo_pattern_t* getSource()
        {
                // cairo_pattern_t* cairo_get_source (cairo_t *cr);
                return cairo_get_source(cairo);
        }
        
        
        /**
         * Set the antialiasing mode of the rasterizer used for drawing shapes.
         * This value is a hint, and a particular backend may or may not support
         * a particular value. At the current time, no backend supports
         * CAIRO_ANTIALIAS_SUBPIXEL when drawing shapes.
         * Note that this option does not affect text rendering, instead see
         * cairo_font_options_set_antialias().
         * cr:
         *  a cairo_t
         * antialias:
         *  the new antialiasing mode
         */
        public void setAntialias(cairo_antialias_t antialias)
        {
                // void cairo_set_antialias (cairo_t *cr,  cairo_antialias_t antialias);
                cairo_set_antialias(cairo, antialias);
        }
        
        /**
         * Gets the current shape antialiasing mode, as set by cairo_set_shape_antialias().
         * cr:
         *  a cairo context
         * Returns:
         *  the current shape antialiasing mode.
         */
        public cairo_antialias_t getAntialias()
        {
                // cairo_antialias_t cairo_get_antialias (cairo_t *cr);
                return cairo_get_antialias(cairo);
        }
        
        /**
         * Sets the dash pattern to be used by cairo_stroke(). A dash pattern
         * is specified by dashes, an array of positive values. Each value
         * provides the length of alternate "on" and "off" portions of the
         * stroke. The offset specifies an offset into the pattern at which
         * the stroke begins.
         * Each "on" segment will have caps applied as if the segment were a
         * separate sub-path. In particular, it is valid to use an "on" length
         * of 0.0 with CAIRO_LINE_CAP_ROUND or CAIRO_LINE_CAP_SQUARE in order
         * to distributed dots or squares along a path.
         * Note: The length values are in user-space units as evaluated at the
         * time of stroking. This is not necessarily the same as the user
         * space at the time of cairo_set_dash().
         * If num_dashes is 0 dashing is disabled.
         * If num_dashes is 1 a symmetric pattern is assumed with alternating
         * on and off portions of the size specified by the single value in
         * dashes.
         * If any value in dashes is negative, or if all values are 0, then
         * cairo_t will be put into an error state with a status of
         * CAIRO_STATUS_INVALID_DASH.
         * cr:
         *  a cairo context
         * dashes:
         *  an array specifying alternate lengths of on and off stroke portions
         * num_dashes:
         *  the length of the dashes array
         * offset:
         *  an offset into the dash pattern at which the stroke should start
         */
        public void setDash(double* dashes, int numDashes, double offset)
        {
                // void cairo_set_dash (cairo_t *cr,  const double *dashes,  int num_dashes,  double offset);
                cairo_set_dash(cairo, dashes, numDashes, offset);
        }
        
        
        /**
         * Set the current fill rule within the cairo context. The fill rule
         * is used to determine which regions are inside or outside a complex
         * (potentially self-intersecting) path. The current fill rule affects
         * both cairo_fill and cairo_clip. See cairo_fill_rule_t for details
         * on the semantics of each available fill rule.
         * cr:
         *  a cairo_t
         * fill_rule:
         *  a fill rule, specified as a cairo_fill_rule_t
         */
        public void setFillRule(cairo_fill_rule_t fillRule)
        {
                // void cairo_set_fill_rule (cairo_t *cr,  cairo_fill_rule_t fill_rule);
                cairo_set_fill_rule(cairo, fillRule);
        }
        
        /**
         * Gets the current fill rule, as set by cairo_set_fill_rule().
         * cr:
         *  a cairo context
         * Returns:
         *  the current fill rule.
         */
        public cairo_fill_rule_t getFillRule()
        {
                // cairo_fill_rule_t cairo_get_fill_rule (cairo_t *cr);
                return cairo_get_fill_rule(cairo);
        }
        
        
        /**
         * Sets the current line cap style within the cairo context. See
         * cairo_line_cap_t for details about how the available line cap
         * styles are drawn.
         * As with the other stroke parameters, the current line cap style is
         * examined by cairo_stroke(), cairo_stroke_extents(), and
         * cairo_stroke_to_path(), but does not have any effect during path
         * construction.
         * cr:
         *  a cairo context, as a cairo_t
         * line_cap:
         *  a line cap style, as a cairo_line_cap_t
         */
        public void setLineCap(cairo_line_cap_t lineCap)
        {
                // void cairo_set_line_cap (cairo_t *cr,  cairo_line_cap_t line_cap);
                cairo_set_line_cap(cairo, lineCap);
        }
        
        /**
         * Gets the current line cap style, as set by cairo_set_line_cap().
         * cr:
         *  a cairo context
         * Returns:
         *  the current line cap style.
         */
        public cairo_line_cap_t getLineCap()
        {
                // cairo_line_cap_t cairo_get_line_cap (cairo_t *cr);
                return cairo_get_line_cap(cairo);
        }
        
        
        /**
         * Sets the current line join style within the cairo context. See
         * cairo_line_join_t for details about how the available line join
         * styles are drawn.
         * As with the other stroke parameters, the current line join style is
         * examined by cairo_stroke(), cairo_stroke_extents(), and
         * cairo_stroke_to_path(), but does not have any effect during path
         * construction.
         * cr:
         *  a cairo context, as a cairo_t
         * line_join:
         *  a line joint style, as a cairo_line_join_t
         */
        public void setLineJoin(cairo_line_join_t lineJoin)
        {
                // void cairo_set_line_join (cairo_t *cr,  cairo_line_join_t line_join);
                cairo_set_line_join(cairo, lineJoin);
        }
        
        /**
         * Gets the current line join style, as set by cairo_set_line_join().
         * cr:
         *  a cairo context
         * Returns:
         *  the current line join style.
         */
        public cairo_line_join_t getLineJoin()
        {
                // cairo_line_join_t cairo_get_line_join (cairo_t *cr);
                return cairo_get_line_join(cairo);
        }
        
        /**
         * Sets the current line width within the cairo context. The line
         * width value specifies the diameter of a pen that is circular in
         * user space, (though device-space pen may be an ellipse in general
         * due to scaling/shear/rotation of the CTM).
         * Note: When the description above refers to user space and CTM it
         * refers to the user space and CTM in effect at the time of the
         * stroking operation, not the user space and CTM in effect at the
         * time of the call to cairo_set_line_width(). The simplest usage
         * makes both of these spaces identical. That is, if there is no
         * change to the CTM between a call to cairo_set_line_with() and the
         * stroking operation, then one can just pass user-space values to
         * cairo_set_line_width() and ignore this note.
         * As with the other stroke parameters, the current line width is
         * examined by cairo_stroke(), cairo_stroke_extents(), and
         * cairo_stroke_to_path(), but does not have any effect during path
         * construction.
         * The default line width value is 2.0.
         * cr:
         *  a cairo_t
         * width:
         *  a line width
         */
        public void setLineWidth(double width)
        {
                // void cairo_set_line_width (cairo_t *cr,  double width);
                cairo_set_line_width(cairo, width);
        }
        
        /**
         * cr:
         *  a cairo context
         * Returns:
         *  the current line width value exactly as set by
         * cairo_set_line_width(). Note that the value is unchanged even if
         * the CTM has changed between the calls to cairo_set_line_width() and
         * cairo_get_line_width().
         */
        public double getLineWidth()
        {
                // double cairo_get_line_width (cairo_t *cr);
                return cairo_get_line_width(cairo);
        }
        
        /**
         * cr:
         * limit:
         */
        public void setMiterLimit(double limit)
        {
                // void cairo_set_miter_limit (cairo_t *cr,  double limit);
                cairo_set_miter_limit(cairo, limit);
        }
        
        /**
         * Gets the current miter limit, as set by cairo_set_miter_limit().
         * cr:
         *  a cairo context
         * Returns:
         *  the current miter limit.
         */
        public double getMiterLimit()
        {
                // double cairo_get_miter_limit (cairo_t *cr);
                return cairo_get_miter_limit(cairo);
        }
        
        
        /**
         * Sets the compositing operator to be used for all drawing
         * operations. See cairo_operator_t for details on the semantics of
         * each available compositing operator.
         * XXX: I'd also like to direct the reader's attention to some
         * (not-yet-written) section on cairo's imaging model. How would I do
         * that if such a section existed? (cworth).
         * cr:
         *  a cairo_t
         * op:
         *  a compositing operator, specified as a cairo_operator_t
         */
        public void setOperator(cairo_operator_t op)
        {
                // void cairo_set_operator (cairo_t *cr,  cairo_operator_t op);
                cairo_set_operator(cairo, op);
        }
        
        /**
         * Gets the current compositing operator for a cairo context.
         * cr:
         *  a cairo context
         * Returns:
         *  the current compositing operator.
         */
        public cairo_operator_t getOperator()
        {
                // cairo_operator_t cairo_get_operator (cairo_t *cr);
                return cairo_get_operator(cairo);
        }
        
        /**
         * Sets the tolerance used when converting paths into trapezoids.
         * Curved segments of the path will be subdivided until the maximum
         * deviation between the original path and the polygonal approximation
         * is less than tolerance. The default value is 0.1. A larger
         * value will give better performance, a smaller value, better
         * appearance. (Reducing the value from the default value of 0.1
         * is unlikely to improve appearance significantly.)
         * cr:
         *  a cairo_t
         * tolerance:
         *  the tolerance, in device units (typically pixels)
         */
        public void setTolerance(double tolerance)
        {
                // void cairo_set_tolerance (cairo_t *cr,  double tolerance);
                cairo_set_tolerance(cairo, tolerance);
        }
        
        /**
         * Gets the current tolerance value, as set by cairo_set_tolerance().
         * cr:
         *  a cairo context
         * Returns:
         *  the current tolerance value.
         */
        public double getTolerance()
        {
                // double cairo_get_tolerance (cairo_t *cr);
                return cairo_get_tolerance(cairo);
        }
        
        /**
         * Establishes a new clip region by intersecting the current clip
         * region with the current path as it would be filled by cairo_fill()
         * and according to the current fill rule (see cairo_set_fill_rule()).
         * After cairo_clip, the current path will be cleared from the cairo
         * context.
         * The current clip region affects all drawing operations by
         * effectively masking out any changes to the surface that are outside
         * the current clip region.
         * Calling cairo_clip() can only make the clip region smaller, never
         * larger. But the current clip is part of the graphics state, so a
         * temporary restriction of the clip region can be achieved by
         * calling cairo_clip() within a cairo_save()/cairo_restore()
         * pair. The only other means of increasing the size of the clip
         * region is cairo_reset_clip().
         * cr:
         *  a cairo context
         */
        public void clip()
        {
                // void cairo_clip (cairo_t *cr);
                cairo_clip(cairo);
        }
        
        /**
         * Establishes a new clip region by intersecting the current clip
         * region with the current path as it would be filled by cairo_fill()
         * and according to the current fill rule (see cairo_set_fill_rule()).
         * Unlike cairo_clip(), cairo_clip_preserve preserves the path within
         * the cairo context.
         * The current clip region affects all drawing operations by
         * effectively masking out any changes to the surface that are outside
         * the current clip region.
         * Calling cairo_clip() can only make the clip region smaller, never
         * larger. But the current clip is part of the graphics state, so a
         * temporary restriction of the clip region can be achieved by
         * calling cairo_clip() within a cairo_save()/cairo_restore()
         * pair. The only other means of increasing the size of the clip
         * region is cairo_reset_clip().
         * cr:
         *  a cairo context
         */
        public void clipPreserve()
        {
                // void cairo_clip_preserve (cairo_t *cr);
                cairo_clip_preserve(cairo);
        }
        
        /**
         * Reset the current clip region to its original, unrestricted
         * state. That is, set the clip region to an infinitely large shape
         * containing the target surface. Equivalently, if infinity is too
         * hard to grasp, one can imagine the clip region being reset to the
         * exact bounds of the target surface.
         * Note that code meant to be reusable should not call
         * cairo_reset_clip() as it will cause results unexpected by
         * higher-level code which calls cairo_clip(). Consider using
         * cairo_save() and cairo_restore() around cairo_clip() as a more
         * robust means of temporarily restricting the clip region.
         * cr:
         *  a cairo context
         */
        public void resetClip()
        {
                // void cairo_reset_clip (cairo_t *cr);
                cairo_reset_clip(cairo);
        }
        
        /**
         * A drawing operator that fills the current path according to the
         * current fill rule, (each sub-path is implicitly closed before being
         * filled). After cairo_fill, the current path will be cleared from
         * the cairo context. See cairo_set_fill_rule() and
         * cairo_fill_preserve().
         * cr:
         *  a cairo context
         */
        public void fill()
        {
                // void cairo_fill (cairo_t *cr);
                cairo_fill(cairo);
        }
        
        /**
         * A drawing operator that fills the current path according to the
         * current fill rule, (each sub-path is implicitly closed before being
         * filled). Unlike cairo_fill(), cairo_fill_preserve preserves the
         * path within the cairo context.
         * See cairo_set_fill_rule() and cairo_fill().
         * cr:
         *  a cairo context
         */
        public void fillPreserve()
        {
                // void cairo_fill_preserve (cairo_t *cr);
                cairo_fill_preserve(cairo);
        }
        
        /**
         * cr:
         * x1:
         * y1:
         * x2:
         * y2:
         */
        public void fillExtents(double* x1, double* y1, double* x2, double* y2)
        {
                // void cairo_fill_extents (cairo_t *cr,  double *x1,  double *y1,  double *x2,  double *y2);
                cairo_fill_extents(cairo, x1, y1, x2, y2);
        }
        
        /**
         * Tests whether the given point is on the area filled by doing a
         * cairo_stroke() operation on cr given the current path and filling
         * parameters.
         * See cairo_fill(), cairo_set_fill_rule() and cairo_fill_preserve().
         * cr:
         *  a cairo context
         * x:
         *  X coordinate of the point to test
         * y:
         *  Y coordinate of the point to test
         * Returns:
         */
        public cairo_bool_t inFill(double x, double y)
        {
                // cairo_bool_t cairo_in_fill (cairo_t *cr,  double x,  double y);
                return cairo_in_fill(cairo, x, y);
        }
        
        /**
         * A drawing operator that paints the current source
         * using the alpha channel of pattern as a mask. (Opaque
         * areas of pattern are painted with the source, transparent
         * areas are not painted.)
         * cr:
         *  a cairo context
         * pattern:
         *  a cairo_pattern_t
         */
        public void mask(cairo_pattern_t* pattern)
        {
                // void cairo_mask (cairo_t *cr,  cairo_pattern_t *pattern);
                cairo_mask(cairo, pattern);
        }
        
        /**
         * A drawing operator that paints the current source
         * using the alpha channel of surface as a mask. (Opaque
         * areas of surface are painted with the source, transparent
         * areas are not painted.)
         * cr:
         *  a cairo context
         * surface:
         *  a cairo_surface_t
         * surface_x:
         *  X coordinate at which to place the origin of surface
         * surface_y:
         *  Y coordinate at which to place the origin of surface
         */
        public void maskSurface(Surface surface, double surfaceX, double surfaceY)
        {
                // void cairo_mask_surface (cairo_t *cr,  cairo_surface_t *surface,  double surface_x,  double surface_y);
                cairo_mask_surface(cairo, (surface is null) ? null : surface.getSurfaceStruct(), surfaceX, surfaceY);
        }
        
        /**
         * A drawing operator that paints the current source everywhere within
         * the current clip region.
         * cr:
         *  a cairo context
         */
        public void paint()
        {
                // void cairo_paint (cairo_t *cr);
                cairo_paint(cairo);
        }
        
        /**
         * A drawing operator that paints the current source everywhere within
         * the current clip region using a mask of constant alpha value
         * alpha. The effect is similar to cairo_paint(), but the drawing
         * is faded out using the alpha value.
         * cr:
         *  a cairo context
         * alpha:
         *  alpha value, between 0 (transparent) and 1 (opaque)
         */
        public void paintWithAlpha(double alpha)
        {
                // void cairo_paint_with_alpha (cairo_t *cr,  double alpha);
                cairo_paint_with_alpha(cairo, alpha);
        }
        
        /**
         * A drawing operator that strokes the current path according to the
         * current line width, line join, line cap, and dash settings. After
         * cairo_stroke, the current path will be cleared from the cairo
         * context. See cairo_set_line_width(), cairo_set_line_join(),
         * cairo_set_line_cap(), cairo_set_dash(), and
         * cairo_stroke_preserve().
         * Note: Degenerate segments and sub-paths are treated specially and
         * provide a useful result. These can result in two different
         * situations:
         * 1. Zero-length "on" segments set in cairo_set_dash(). If the cap
         * style is CAIRO_LINE_CAP_ROUND or CAIRO_LINE_CAP_SQUARE then these
         * segments will be drawn as circular dots or squares respectively. In
         * the case of CAIRO_LINE_CAP_SQUARE, the orientation of the squares
         * is determined by the direction of the underlying path.
         * 2. A sub-path created by cairo_move_to() followed by either a
         * cairo_close_path() or one or more calls to cairo_line_to() to the
         * same coordinate as the cairo_move_to(). If the cap style is
         * CAIRO_LINE_CAP_ROUND then these sub-paths will be drawn as circular
         * dots. Note that in the case of CAIRO_LINE_CAP_SQUARE a degenerate
         * sub-path will not be drawn at all, (since the correct orientation
         * is indeterminate).
         * In no case will a cap style of CAIRO_LINE_CAP_BUTT cause anything
         * to be drawn in the case of either degenerate segments or sub-paths.
         * cr:
         *  a cairo context
         */
        public void stroke()
        {
                // void cairo_stroke (cairo_t *cr);
                cairo_stroke(cairo);
        }
        
        /**
         * A drawing operator that strokes the current path according to the
         * current line width, line join, line cap, and dash settings. Unlike
         * cairo_stroke(), cairo_stroke_preserve preserves the path within the
         * cairo context.
         * See cairo_set_line_width(), cairo_set_line_join(),
         * cairo_set_line_cap(), cairo_set_dash(), and
         * cairo_stroke_preserve().
         * cr:
         *  a cairo context
         */
        public void strokePreserve()
        {
                // void cairo_stroke_preserve (cairo_t *cr);
                cairo_stroke_preserve(cairo);
        }
        
        /**
         * cr:
         * x1:
         * y1:
         * x2:
         * y2:
         */
        public void strokeExtents(double* x1, double* y1, double* x2, double* y2)
        {
                // void cairo_stroke_extents (cairo_t *cr,  double *x1,  double *y1,  double *x2,  double *y2);
                cairo_stroke_extents(cairo, x1, y1, x2, y2);
        }
        
        /**
         * Tests whether the given point is on the area stroked by doing a
         * cairo_stroke() operation on cr given the current path and stroking
         * parameters.
         * See cairo_stroke, cairo_set_line_width(), cairo_set_line_join(),
         * cairo_set_line_cap(), cairo_set_dash(), and
         * cairo_stroke_preserve().
         * cr:
         *  a cairo context
         * x:
         *  X coordinate of the point to test
         * y:
         *  Y coordinate of the point to test
         * Returns:
         */
        public cairo_bool_t inStroke(double x, double y)
        {
                // cairo_bool_t cairo_in_stroke (cairo_t *cr,  double x,  double y);
                return cairo_in_stroke(cairo, x, y);
        }
        
        /**
         * Emits the current page for backends that support multiple pages, but
         * doesn't clear it, so, the contents of the current page will be retained
         * for the next page too. Use cairo_show_page() if you want to get an
         * empty page after the emission.
         * cr:
         *  a cairo context
         */
        public void copyPage()
        {
                // void cairo_copy_page (cairo_t *cr);
                cairo_copy_page(cairo);
        }
        
        /**
         * Emits and clears the current page for backends that support multiple
         * pages. Use cairo_copy_page() if you don't want to clear the page.
         * cr:
         *  a cairo context
         */
        public void showPage()
        {
                // void cairo_show_page (cairo_t *cr);
                cairo_show_page(cairo);
        }
        
        
        
        
        /**
         * Creates a copy of the current path and returns it to the user as a
         * cairo_path_t. See cairo_path_data_t for hints on how to iterate
         * over the returned data structure.
         * This function will always return a valid pointer, but the result
         * will have no data (data==NULL and
         * num_data==0), if either of the following
         * conditions hold:
         * If there is insufficient memory to copy the path.
         * If cr is already in an error state.
         * In either case, path->status will be set to
         * CAIRO_STATUS_NO_MEMORY (regardless of what the error status in
         * cr might have been).
         * cr:
         *  a cairo context
         * Returns:
         *  the copy of the current path. The caller owns the
         * returned object and should call cairo_path_destroy() when finished
         * with it.
         */
        public cairo_path_t* copyPath()
        {
                // cairo_path_t* cairo_copy_path (cairo_t *cr);
                return cairo_copy_path(cairo);
        }
        
        /**
         * Gets a flattened copy of the current path and returns it to the
         * user as a cairo_path_t. See cairo_path_data_t for hints on
         * how to iterate over the returned data structure.
         * This function is like cairo_copy_path() except that any curves
         * in the path will be approximated with piecewise-linear
         * approximations, (accurate to within the current tolerance
         * value). That is, the result is guaranteed to not have any elements
         * of type CAIRO_PATH_CURVE_TO which will instead be replaced by a
         * series of CAIRO_PATH_LINE_TO elements.
         * This function will always return a valid pointer, but the result
         * will have no data (data==NULL and
         * num_data==0), if either of the following
         * conditions hold:
         * If there is insufficient memory to copy the path. In this
         *  case path->status will be set to
         *  CAIRO_STATUS_NO_MEMORY.
         * If cr is already in an error state. In this case
         *  path->status will contain the same status that
         *  would be returned by cairo_status().
         * cr:
         *  a cairo context
         * Returns:
         *  the copy of the current path. The caller owns the
         * returned object and should call cairo_path_destroy() when finished
         * with it.
         */
        public cairo_path_t* copyPathFlat()
        {
                // cairo_path_t* cairo_copy_path_flat (cairo_t *cr);
                return cairo_copy_path_flat(cairo);
        }
        
        /**
         * Immediately releases all memory associated with path. After a call
         * to cairo_path_destroy() the path pointer is no longer valid and
         * should not be used further.
         * NOTE: cairo_path_destroy function should only be called with a
         * pointer to a cairo_path_t returned by a cairo function. Any path
         * that is created manually (ie. outside of cairo) should be destroyed
         * manually as well.
         * path:
         *  a path previously returned by either cairo_copy_path() or
         * cairo_copy_path_flat().
         */
        public static void pathDestroy(cairo_path_t* path)
        {
                // void cairo_path_destroy (cairo_path_t *path);
                cairo_path_destroy(path);
        }
        
        /**
         * Append the path onto the current path. The path may be either the
         * return value from one of cairo_copy_path() or
         * cairo_copy_path_flat() or it may be constructed manually. See
         * cairo_path_t for details on how the path data structure should be
         * initialized, and note that path->status must be
         * initialized to CAIRO_STATUS_SUCCESS.
         * cr:
         *  a cairo context
         * path:
         *  path to be appended
         */
        public void appendPath(cairo_path_t* path)
        {
                // void cairo_append_path (cairo_t *cr,  cairo_path_t *path);
                cairo_append_path(cairo, path);
        }
        
        /**
         * Gets the current point of the current path, which is
         * conceptually the final point reached by the path so far.
         * The current point is returned in the user-space coordinate
         * system. If there is no defined current point then x and y will
         * both be set to 0.0.
         * Most path construction functions alter the current point. See the
         * following for details on how they affect the current point:
         * cairo_new_path(), cairo_move_to(), cairo_line_to(),
         * cairo_curve_to(), cairo_arc(), cairo_rel_move_to(),
         * cairo_rel_line_to(), cairo_rel_curve_to(), cairo_arc(),
         * cairo_text_path(), cairo_stroke_to_path()
         * cr:
         *  a cairo context
         * x:
         *  return value for X coordinate of the current point
         * y:
         *  return value for Y coordinate of the current point
         */
        public void getCurrentPoint(double* x, double* y)
        {
                // void cairo_get_current_point (cairo_t *cr,  double *x,  double *y);
                cairo_get_current_point(cairo, x, y);
        }
        
        /**
         * Clears the current path. After this call there will be no path and
         * no current point.
         * cr:
         *  a cairo context
         */
        public void newPath()
        {
                // void cairo_new_path (cairo_t *cr);
                cairo_new_path(cairo);
        }
        
        /**
         * Begin a new sub-path. Note that the existing path is not
         * affected. After this call there will be no current point.
         * In many cases, this call is not needed since new sub-paths are
         * frequently started with cairo_move_to().
         * A call to cairo_new_sub_path() is particularly useful when
         * beginning a new sub-path with one of the cairo_arc() calls. This
         * makes things easier as it is no longer necessary to manually
         * compute the arc's initial coordinates for a call to
         * cairo_move_to().
         * cr:
         *  a cairo context
         * Since 1.2
         */
        public void newSubPath()
        {
                // void cairo_new_sub_path (cairo_t *cr);
                cairo_new_sub_path(cairo);
        }
        
        /**
         * Adds a line segment to the path from the current point to the
         * beginning of the current sub-path, (the most recent point passed to
         * cairo_move_to()), and closes this sub-path. After this call the
         * current point will be at the joined endpoint of the sub-path.
         * The behavior of cairo_close_path() is distinct from simply calling
         * cairo_line_to() with the equivalent coordinate in the case of
         * stroking. When a closed sub-path is stroked, there are no caps on
         * the ends of the sub-path. Instead, there is a line join connecting
         * the final and initial segments of the sub-path.
         * If there is no current point before the call to cairo_close_path,
         * this function will have no effect.
         * Note: As of cairo version 1.2.4 any call to cairo_close_path will
         * place an explicit MOVE_TO element into the path immediately after
         * the CLOSE_PATH element, (which can be seen in cairo_copy_path() for
         * example). This can simplify path processing in some cases as it may
         * not be necessary to save the "last move_to point" during processing
         * as the MOVE_TO immediately after the CLOSE_PATH will provide that
         * point.
         * cr:
         *  a cairo context
         */
        public void closePath()
        {
                // void cairo_close_path (cairo_t *cr);
                cairo_close_path(cairo);
        }
        
        /**
         * Adds a circular arc of the given radius to the current path. The
         * arc is centered at (xc, yc), begins at angle1 and proceeds in
         * the direction of increasing angles to end at angle2. If angle2 is
         * less than angle1 it will be progressively increased by 2*M_PI
         * until it is greater than angle1.
         * If there is a current point, an initial line segment will be added
         * to the path to connect the current point to the beginning of the
         * arc.
         * Angles are measured in radians. An angle of 0.0 is in the direction
         * of the positive X axis (in user space). An angle of M_PI/2.0 radians
         * (90 degrees) is in the direction of the positive Y axis (in
         * user space). Angles increase in the direction from the positive X
         * axis toward the positive Y axis. So with the default transformation
         * matrix, angles increase in a clockwise direction.
         * (To convert from degrees to radians, use degrees * (M_PI /
         * 180.).)
         * This function gives the arc in the direction of increasing angles;
         * see cairo_arc_negative() to get the arc in the direction of
         * decreasing angles.
         * The arc is circular in user space. To achieve an elliptical arc,
         * you can scale the current transformation matrix by different
         * amounts in the X and Y directions. For example, to draw an ellipse
         * in the box given by x, y, width, height:
         * cairo_save (cr);
         * cairo_translate (cr, x + width / 2., y + height / 2.);
         * cairo_scale (cr, 1. / (height / 2.), 1. / (width / 2.));
         * cairo_arc (cr, 0., 0., 1., 0., 2 * M_PI);
         * cairo_restore (cr);
         * cr:
         *  a cairo context
         * xc:
         *  X position of the center of the arc
         * yc:
         *  Y position of the center of the arc
         * radius:
         *  the radius of the arc
         * angle1:
         *  the start angle, in radians
         * angle2:
         *  the end angle, in radians
         */
        public void arc(double xc, double yc, double radius, double angle1, double angle2)
        {
                // void cairo_arc (cairo_t *cr,  double xc,  double yc,  double radius,  double angle1,  double angle2);
                cairo_arc(cairo, xc, yc, radius, angle1, angle2);
        }
        
        /**
         * Adds a circular arc of the given radius to the current path. The
         * arc is centered at (xc, yc), begins at angle1 and proceeds in
         * the direction of decreasing angles to end at angle2. If angle2 is
         * greater than angle1 it will be progressively decreased by 2*M_PI
         * until it is greater than angle1.
         * See cairo_arc() for more details. This function differs only in the
         * direction of the arc between the two angles.
         * cr:
         *  a cairo context
         * xc:
         *  X position of the center of the arc
         * yc:
         *  Y position of the center of the arc
         * radius:
         *  the radius of the arc
         * angle1:
         *  the start angle, in radians
         * angle2:
         *  the end angle, in radians
         */
        public void arcNegative(double xc, double yc, double radius, double angle1, double angle2)
        {
                // void cairo_arc_negative (cairo_t *cr,  double xc,  double yc,  double radius,  double angle1,  double angle2);
                cairo_arc_negative(cairo, xc, yc, radius, angle1, angle2);
        }
        
        /**
         * Adds a cubic Bzier spline to the path from the current point to
         * position (x3, y3) in user-space coordinates, using (x1, y1) and
         * (x2, y2) as the control points. After this call the current point
         * will be (x3, y3).
         * If there is no current point before the call to cairo_curve_to()
         * this function will behave as if preceded by a call to
         * cairo_move_to (cr, x1, y1).
         * cr:
         *  a cairo context
         * x1:
         *  the X coordinate of the first control point
         * y1:
         *  the Y coordinate of the first control point
         * x2:
         *  the X coordinate of the second control point
         * y2:
         *  the Y coordinate of the second control point
         * x3:
         *  the X coordinate of the end of the curve
         * y3:
         *  the Y coordinate of the end of the curve
         */
        public void curveTo(double x1, double y1, double x2, double y2, double x3, double y3)
        {
                // void cairo_curve_to (cairo_t *cr,  double x1,  double y1,  double x2,  double y2,  double x3,  double y3);
                cairo_curve_to(cairo, x1, y1, x2, y2, x3, y3);
        }
        
        /**
         * Adds a line to the path from the current point to position (x, y)
         * in user-space coordinates. After this call the current point
         * will be (x, y).
         * If there is no current point before the call to cairo_line_to()
         * this function will behave as cairo_move_to (cr, x, y).
         * cr:
         *  a cairo context
         * x:
         *  the X coordinate of the end of the new line
         * y:
         *  the Y coordinate of the end of the new line
         */
        public void lineTo(double x, double y)
        {
                // void cairo_line_to (cairo_t *cr,  double x,  double y);
                cairo_line_to(cairo, x, y);
        }
        
        /**
         * Begin a new sub-path. After this call the current point will be (x,
         * y).
         * cr:
         *  a cairo context
         * x:
         *  the X coordinate of the new position
         * y:
         *  the Y coordinate of the new position
         */
        public void moveTo(double x, double y)
        {
                // void cairo_move_to (cairo_t *cr,  double x,  double y);
                cairo_move_to(cairo, x, y);
        }
        
        /**
         * Adds a closed sub-path rectangle of the given size to the current
         * path at position (x, y) in user-space coordinates.
         * This function is logically equivalent to:
         * cairo_move_to (cr, x, y);
         * cairo_rel_line_to (cr, width, 0);
         * cairo_rel_line_to (cr, 0, height);
         * cairo_rel_line_to (cr, -width, 0);
         * cairo_close_path (cr);
         * cr:
         *  a cairo context
         * x:
         *  the X coordinate of the top left corner of the rectangle
         * y:
         *  the Y coordinate to the top left corner of the rectangle
         * width:
         *  the width of the rectangle
         * height:
         *  the height of the rectangle
         */
        public void rectangle(double x, double y, double width, double height)
        {
                // void cairo_rectangle (cairo_t *cr,  double x,  double y,  double width,  double height);
                cairo_rectangle(cairo, x, y, width, height);
        }
        
        /**
         * cr:
         * glyphs:
         * num_glyphs:
         */
        public void glyphPath(cairo_glyph_t* glyphs, int numGlyphs)
        {
                // void cairo_glyph_path (cairo_t *cr,  cairo_glyph_t *glyphs,  int num_glyphs);
                cairo_glyph_path(cairo, glyphs, numGlyphs);
        }
        
        /**
         * cr:
         * utf8:
         */
        public void textPath(char[] utf8)
        {
                // void cairo_text_path (cairo_t *cr,  const char *utf8);
                cairo_text_path(cairo, Str.toStringz(utf8));
        }
        
        /**
         * Relative-coordinate version of cairo_curve_to(). All offsets are
         * relative to the current point. Adds a cubic Bzier spline to the
         * path from the current point to a point offset from the current
         * point by (dx3, dy3), using points offset by (dx1, dy1) and
         * (dx2, dy2) as the control points. After this call the current
         * point will be offset by (dx3, dy3).
         * Given a current point of (x, y), cairo_rel_curve_to (cr, dx1,
         * dy1, dx2, dy2, dx3, dy3) is logically equivalent to
         * cairo_curve_to (cr, x + dx1, y + dy1, x + dx2, y + dy2, x +
         * dx3, y + dy3).
         * It is an error to call this function with no current point. Doing
         * so will cause cr to shutdown with a status of
         * CAIRO_STATUS_NO_CURRENT_POINT.
         * cr:
         *  a cairo context
         * dx1:
         *  the X offset to the first control point
         * dy1:
         *  the Y offset to the first control point
         * dx2:
         *  the X offset to the second control point
         * dy2:
         *  the Y offset to the second control point
         * dx3:
         *  the X offset to the end of the curve
         * dy3:
         *  the Y offset to the end of the curve
         */
        public void relCurveTo(double dx1, double dy1, double dx2, double dy2, double dx3, double dy3)
        {
                // void cairo_rel_curve_to (cairo_t *cr,  double dx1,  double dy1,  double dx2,  double dy2,  double dx3,  double dy3);
                cairo_rel_curve_to(cairo, dx1, dy1, dx2, dy2, dx3, dy3);
        }
        
        /**
         * Relative-coordinate version of cairo_line_to(). Adds a line to the
         * path from the current point to a point that is offset from the
         * current point by (dx, dy) in user space. After this call the
         * current point will be offset by (dx, dy).
         * Given a current point of (x, y), cairo_rel_line_to(cr, dx, dy)
         * is logically equivalent to cairo_line_to (cr, x + dx, y + dy).
         * It is an error to call this function with no current point. Doing
         * so will cause cr to shutdown with a status of
         * CAIRO_STATUS_NO_CURRENT_POINT.
         * cr:
         *  a cairo context
         * dx:
         *  the X offset to the end of the new line
         * dy:
         *  the Y offset to the end of the new line
         */
        public void relLineTo(double dx, double dy)
        {
                // void cairo_rel_line_to (cairo_t *cr,  double dx,  double dy);
                cairo_rel_line_to(cairo, dx, dy);
        }
        
        /**
         * Begin a new sub-path. After this call the current point will offset
         * by (x, y).
         * Given a current point of (x, y), cairo_rel_move_to(cr, dx, dy)
         * is logically equivalent to cairo_move_to (cr, x + dx, y + dy).
         * It is an error to call this function with no current point. Doing
         * so will cause cr to shutdown with a status of
         * CAIRO_STATUS_NO_CURRENT_POINT.
         * cr:
         *  a cairo context
         * dx:
         *  the X offset
         * dy:
         *  the Y offset
         */
        public void relMoveTo(double dx, double dy)
        {
                // void cairo_rel_move_to (cairo_t *cr,  double dx,  double dy);
                cairo_rel_move_to(cairo, dx, dy);
        }
        
        /**
         * Modifies the current transformation matrix (CTM) by translating the
         * user-space origin by (tx, ty). This offset is interpreted as a
         * user-space coordinate according to the CTM in place before the new
         * call to cairo_translate. In other words, the translation of the
         * user-space origin takes place after any existing transformation.
         * cr:
         *  a cairo context
         * tx:
         *  amount to translate in the X direction
         * ty:
         *  amount to translate in the Y direction
         */
        public void translate(double tx, double ty)
        {
                // void cairo_translate (cairo_t *cr,  double tx,  double ty);
                cairo_translate(cairo, tx, ty);
        }
        
        /**
         * Modifies the current transformation matrix (CTM) by scaling the X
         * and Y user-space axes by sx and sy respectively. The scaling of
         * the axes takes place after any existing transformation of user
         * space.
         * cr:
         *  a cairo context
         * sx:
         *  scale factor for the X dimension
         * sy:
         *  scale factor for the Y dimension
         */
        public void scale(double sx, double sy)
        {
                // void cairo_scale (cairo_t *cr,  double sx,  double sy);
                cairo_scale(cairo, sx, sy);
        }
        
        /**
         * Modifies the current transformation matrix (CTM) by rotating the
         * user-space axes by angle radians. The rotation of the axes takes
         * places after any existing transformation of user space. The
         * rotation direction for positive angles is from the positive X axis
         * toward the positive Y axis.
         * cr:
         *  a cairo context
         * angle:
         *  angle (in radians) by which the user-space axes will be
         * rotated
         */
        public void rotate(double angle)
        {
                // void cairo_rotate (cairo_t *cr,  double angle);
                cairo_rotate(cairo, angle);
        }
        
        /**
         * Modifies the current transformation matrix (CTM) by applying
         * matrix as an additional transformation. The new transformation of
         * user space takes place after any existing transformation.
         * cr:
         *  a cairo context
         * matrix:
         *  a transformation to be applied to the user-space axes
         */
        public void transform(cairo_matrix_t* matrix)
        {
                // void cairo_transform (cairo_t *cr,  const cairo_matrix_t *matrix);
                cairo_transform(cairo, matrix);
        }
        
        /**
         * Modifies the current transformation matrix (CTM) by setting it
         * equal to matrix.
         * cr:
         *  a cairo context
         * matrix:
         *  a transformation matrix from user space to device space
         */
        public void setMatrix(cairo_matrix_t* matrix)
        {
                // void cairo_set_matrix (cairo_t *cr,  const cairo_matrix_t *matrix);
                cairo_set_matrix(cairo, matrix);
        }
        
        /**
         * Stores the current transformation matrix (CTM) into matrix.
         * cr:
         *  a cairo context
         * matrix:
         *  return value for the matrix
         */
        public void getMatrix(cairo_matrix_t* matrix)
        {
                // void cairo_get_matrix (cairo_t *cr,  cairo_matrix_t *matrix);
                cairo_get_matrix(cairo, matrix);
        }
        
        /**
         * Resets the current transformation matrix (CTM) by setting it equal
         * to the identity matrix. That is, the user-space and device-space
         * axes will be aligned and one user-space unit will transform to one
         * device-space unit.
         * cr:
         *  a cairo context
         */
        public void identityMatrix()
        {
                // void cairo_identity_matrix (cairo_t *cr);
                cairo_identity_matrix(cairo);
        }
        
        /**
         * Transform a coordinate from user space to device space by
         * multiplying the given point by the current transformation matrix
         * (CTM).
         * cr:
         *  a cairo context
         * x:
         *  X value of coordinate (in/out parameter)
         * y:
         *  Y value of coordinate (in/out parameter)
         */
        public void userToDevice(double* x, double* y)
        {
                // void cairo_user_to_device (cairo_t *cr,  double *x,  double *y);
                cairo_user_to_device(cairo, x, y);
        }
        
        /**
         * Transform a distance vector from user space to device space. This
         * function is similar to cairo_user_to_device() except that the
         * translation components of the CTM will be ignored when transforming
         * (dx,dy).
         * cr:
         *  a cairo context
         * dx:
         *  X component of a distance vector (in/out parameter)
         * dy:
         *  Y component of a distance vector (in/out parameter)
         */
        public void userToDeviceDistance(double* dx, double* dy)
        {
                // void cairo_user_to_device_distance (cairo_t *cr,  double *dx,  double *dy);
                cairo_user_to_device_distance(cairo, dx, dy);
        }
        
        /**
         * Transform a coordinate from device space to user space by
         * multiplying the given point by the inverse of the current
         * transformation matrix (CTM).
         * cr:
         *  a cairo
         * x:
         *  X value of coordinate (in/out parameter)
         * y:
         *  Y value of coordinate (in/out parameter)
         */
        public void deviceToUser(double* x, double* y)
        {
                // void cairo_device_to_user (cairo_t *cr,  double *x,  double *y);
                cairo_device_to_user(cairo, x, y);
        }
        
        /**
         * Transform a distance vector from device space to user space. This
         * function is similar to cairo_device_to_user() except that the
         * translation components of the inverse CTM will be ignored when
         * transforming (dx,dy).
         * cr:
         *  a cairo context
         * dx:
         *  X component of a distance vector (in/out parameter)
         * dy:
         *  Y component of a distance vector (in/out parameter)
         */
        public void deviceToUserDistance(double* dx, double* dy)
        {
                // void cairo_device_to_user_distance (cairo_t *cr,  double *dx,  double *dy);
                cairo_device_to_user_distance(cairo, dx, dy);
        }
        
        
        
        
        /**
         * Selects a family and style of font from a simplified description as
         * a family name, slant and weight. This function is meant to be used
         * only for applications with simple font needs: Cairo doesn't provide
         * for operations such as listing all available fonts on the system,
         * and it is expected that most applications will need to use a more
         * comprehensive font handling and text layout library in addition to
         * cairo.
         * cr:
         *  a cairo_t
         * family:
         *  a font family name, encoded in UTF-8
         * slant:
         *  the slant for the font
         * weight:
         *  the weight for the font
         */
        public void selectFontFace(char[] family, cairo_font_slant_t slant, cairo_font_weight_t weight)
        {
                // void cairo_select_font_face (cairo_t *cr,  const char *family,  cairo_font_slant_t slant,  cairo_font_weight_t weight);
                cairo_select_font_face(cairo, Str.toStringz(family), slant, weight);
        }
        
        /**
         * Sets the current font matrix to a scale by a factor of size, replacing
         * any font matrix previously set with cairo_set_font_size() or
         * cairo_set_font_matrix(). This results in a font size of size user space
         * units. (More precisely, this matrix will result in the font's
         * em-square being a size by size square in user space.)
         * cr:
         *  a cairo_t
         * size:
         *  the new font size, in user space units
         */
        public void setFontSize(double size)
        {
                // void cairo_set_font_size (cairo_t *cr,  double size);
                cairo_set_font_size(cairo, size);
        }
        
        /**
         * Sets the current font matrix to matrix. The font matrix gives a
         * transformation from the design space of the font (in this space,
         * the em-square is 1 unit by 1 unit) to user space. Normally, a
         * simple scale is used (see cairo_set_font_size()), but a more
         * complex font matrix can be used to shear the font
         * or stretch it unequally along the two axes
         * cr:
         *  a cairo_t
         * matrix:
         *  a cairo_matrix_t describing a transform to be applied to
         * the current font.
         */
        public void setFontMatrix(cairo_matrix_t* matrix)
        {
                // void cairo_set_font_matrix (cairo_t *cr,  const cairo_matrix_t *matrix);
                cairo_set_font_matrix(cairo, matrix);
        }
        
        /**
         * Stores the current font matrix into matrix. See
         * cairo_set_font_matrix().
         * cr:
         *  a cairo_t
         * matrix:
         *  return value for the matrix
         */
        public void getFontMatrix(cairo_matrix_t* matrix)
        {
                // void cairo_get_font_matrix (cairo_t *cr,  cairo_matrix_t *matrix);
                cairo_get_font_matrix(cairo, matrix);
        }
        
        /**
         * Sets a set of custom font rendering options for the cairo_t.
         * Rendering options are derived by merging these options with the
         * options derived from underlying surface; if the value in options
         * has a default value (like CAIRO_ANTIALIAS_DEFAULT), then the value
         * from the surface is used.
         * cr:
         *  a cairo_t
         * options:
         *  font options to use
         */
        public void setFontOptions(cairo_font_options_t* options)
        {
                // void cairo_set_font_options (cairo_t *cr,  const cairo_font_options_t *options);
                cairo_set_font_options(cairo, options);
        }
        
        /**
         * Retrieves font rendering options set via cairo_set_font_options.
         * Note that the returned options do not include any options derived
         * from the underlying surface; they are literally the options
         * passed to cairo_set_font_options().
         * cr:
         *  a cairo_t
         * options:
         *  a cairo_font_options_t object into which to store
         *  the retrieved options. All existing values are overwritten
         */
        public void getFontOptions(cairo_font_options_t* options)
        {
                // void cairo_get_font_options (cairo_t *cr,  cairo_font_options_t *options);
                cairo_get_font_options(cairo, options);
        }
        
        /**
         * A drawing operator that generates the shape from a string of UTF-8
         * characters, rendered according to the current font_face, font_size
         * (font_matrix), and font_options.
         * This function first computes a set of glyphs for the string of
         * text. The first glyph is placed so that its origin is at the
         * current point. The origin of each subsequent glyph is offset from
         * that of the previous glyph by the advance values of the previous
         * glyph.
         * After this call the current point is moved to the origin of where
         * the next glyph would be placed in this same progression. That is,
         * the current point will be at the origin of the final glyph offset
         * by its advance values. This allows for easy display of a single
         * logical string with multiple calls to cairo_show_text().
         * NOTE: The cairo_show_text() function call is part of what the cairo
         * designers call the "toy" text API. It is convenient for short demos
         * and simple programs, but it is not expected to be adequate for the
         * most serious of text-using applications. See cairo_show_glyphs()
         * for the "real" text display API in cairo.
         * cr:
         *  a cairo context
         * utf8:
         *  a string of text encoded in UTF-8
         */
        public void showText(char[] utf8)
        {
                // void cairo_show_text (cairo_t *cr,  const char *utf8);
                cairo_show_text(cairo, Str.toStringz(utf8));
        }
        
        /**
         * cr:
         * glyphs:
         * num_glyphs:
         */
        public void showGlyphs(cairo_glyph_t* glyphs, int numGlyphs)
        {
                // void cairo_show_glyphs (cairo_t *cr,  cairo_glyph_t *glyphs,  int num_glyphs);
                cairo_show_glyphs(cairo, glyphs, numGlyphs);
        }
        
        /**
         * Gets the current font face for a cairo_t.
         * cr:
         *  a cairo_t
         * Returns:
         *  the current font object. Can return NULL
         *  on out-of-memory or if the context is already in
         *  an error state. This object is owned by cairo. To keep
         *  a reference to it, you must call cairo_font_face_reference().
         */
        public cairo_font_face_t* getFontFace()
        {
                // cairo_font_face_t* cairo_get_font_face (cairo_t *cr);
                return cairo_get_font_face(cairo);
        }
        
        /**
         * Gets the font extents for the currently selected font.
         * cr:
         *  a cairo_t
         * extents:
         *  a cairo_font_extents_t object into which the results
         * will be stored.
         */
        public void fontExtents(cairo_font_extents_t* extents)
        {
                // void cairo_font_extents (cairo_t *cr,  cairo_font_extents_t *extents);
                cairo_font_extents(cairo, extents);
        }
        
        /**
         * Replaces the current cairo_font_face_t object in the cairo_t with
         * font_face. The replaced font face in the cairo_t will be
         * destroyed if there are no other references to it.
         * cr:
         *  a cairo_t
         * font_face:
         *  a cairo_font_face_t, or NULL to restore to the default font
         */
        public void setFontFace(cairo_font_face_t* fontFace)
        {
                // void cairo_set_font_face (cairo_t *cr,  cairo_font_face_t *font_face);
                cairo_set_font_face(cairo, fontFace);
        }
        
        /**
         * Replaces the current font face, font matrix, and font options in
         * the cairo_t with those of the cairo_scaled_font_t. Except for
         * some translation, the current CTM of the cairo_t should be the
         * same as that of the cairo_scaled_font_t, which can be accessed
         * using cairo_scaled_font_get_ctm().
         * cr:
         *  a cairo_t
         * scaled_font:
         *  a cairo_scaled_font_t
         * Since 1.2
         */
        public void setScaledFont(cairo_scaled_font_t* scaledFont)
        {
                // void cairo_set_scaled_font (cairo_t *cr,  const cairo_scaled_font_t *scaled_font);
                cairo_set_scaled_font(cairo, scaledFont);
        }
        
        /**
         * Gets the extents for a string of text. The extents describe a
         * user-space rectangle that encloses the "inked" portion of the text,
         * (as it would be drawn by cairo_show_text()). Additionally, the
         * x_advance and y_advance values indicate the amount by which the
         * current point would be advanced by cairo_show_text().
         * Note that whitespace characters do not directly contribute to the
         * size of the rectangle (extents.width and extents.height). They do
         * contribute indirectly by changing the position of non-whitespace
         * characters. In particular, trailing whitespace characters are
         * likely to not affect the size of the rectangle, though they will
         * affect the x_advance and y_advance values.
         * cr:
         *  a cairo_t
         * utf8:
         *  a string of text, encoded in UTF-8
         * extents:
         *  a cairo_text_extents_t object into which the results
         * will be stored
         */
        public void textExtents(char[] utf8, cairo_text_extents_t* extents)
        {
                // void cairo_text_extents (cairo_t *cr,  const char *utf8,  cairo_text_extents_t *extents);
                cairo_text_extents(cairo, Str.toStringz(utf8), extents);
        }
        
        /**
         * Gets the extents for an array of glyphs. The extents describe a
         * user-space rectangle that encloses the "inked" portion of the
         * glyphs, (as they would be drawn by cairo_show_glyphs()).
         * Additionally, the x_advance and y_advance values indicate the
         * amount by which the current point would be advanced by
         * cairo_show_glyphs.
         * Note that whitespace glyphs do not contribute to the size of the
         * rectangle (extents.width and extents.height).
         * cr:
         *  a cairo_t
         * glyphs:
         *  an array of cairo_glyph_t objects
         * num_glyphs:
         *  the number of elements in glyphs
         * extents:
         *  a cairo_text_extents_t object into which the results
         * will be stored
         */
        public void glyphExtents(cairo_glyph_t* glyphs, int numGlyphs, cairo_text_extents_t* extents)
        {
                // void cairo_glyph_extents (cairo_t *cr,  cairo_glyph_t *glyphs,  int num_glyphs,  cairo_text_extents_t *extents);
                cairo_glyph_extents(cairo, glyphs, numGlyphs, extents);
        }
}