kscreensaver/xsavers/xs_colors.h

   1 /* xscreensaver, Copyright (c) 1992, 1997 Jamie Zawinski <jwz@jwz.org>
   2  *
   3  * Permission to use, copy, modify, distribute, and sell this software and its
   4  * documentation for any purpose is hereby granted without fee, provided that
   5  * the above copyright notice appear in all copies and that both that
   6  * copyright notice and this permission notice appear in supporting
   7  * documentation.  No representations are made about the suitability of this
   8  * software for any purpose.  It is provided "as is" without express or
   9  * implied warranty.
  10  */
  11
  12 #ifndef __COLORS_H__
  13 #define __COLORS_H__
  14
  15 /* Like XFreeColors, but works on `XColor *' instead of `unsigned long *'
  16  */
  17 extern void free_colors (Display *, Colormap, XColor *, int ncolors);
  18
  19
  20 /* Allocates writable, non-contiguous color cells.  The number requested is
  21    passed in *ncolorsP, and the number actually allocated is returned there.
  22    (Unlike XAllocColorCells(), this will allocate as many as it can, instead
  23    of failing if they can't all be allocated.)
  24  */
  25 extern void allocate_writable_colors (Display *dpy, Colormap cmap,
  26                                       unsigned long *pixels, int *ncolorsP);
  27
  28
  29 /* Generates a sequence of colors evenly spaced between the given pair
  30    of HSV coordinates.
  31
  32    If closed_p is true, the colors will go from the first point to the
  33    second then back to the first.
  34
  35    If allocate_p is true, the colors will be allocated from the map;
  36    if enough colors can't be allocated, we will try for less, and the
  37    result will be returned to ncolorsP.
  38
  39    If writable_p is true, writable color cells will be allocated;
  40    otherwise, read-only cells will be allocated.
  41  */
  42 extern void make_color_ramp (Display *dpy, Colormap cmap,
  43                              int h1, double s1, double v1,
  44                              int h2, double s2, double v2,
  45                              XColor *colors, int *ncolorsP,
  46                              Bool closed_p,
  47                              Bool allocate_p,
  48                              Bool writable_p);
  49
  50 /* Generates a sequence of colors evenly spaced around the triangle
  51    indicated by the thee HSV coordinates.
  52
  53    If allocate_p is true, the colors will be allocated from the map;
  54    if enough colors can't be allocated, we will try for less, and the
  55    result will be returned to ncolorsP.
  56
  57    If writable_p is true, writable color cells will be allocated;
  58    otherwise, read-only cells will be allocated.
  59  */
  60 extern void make_color_loop (Display *, Colormap,
  61                              int h1, double s1, double v1,
  62                              int h2, double s2, double v2,
  63                              int h3, double s3, double v3,
  64                              XColor *colors, int *ncolorsP,
  65                              Bool allocate_p,
  66                              Bool writable_p);
  67
  68
  69 /* Allocates a hopefully-interesting colormap, which will be a closed loop
  70    without any sudden transitions.
  71
  72    If allocate_p is true, the colors will be allocated from the map;
  73    if enough colors can't be allocated, we will try for less, and the
  74    result will be returned to ncolorsP.  An error message will be
  75    printed on stderr (if verbose_p).
  76
  77    If *writable_pP is true, writable color cells will be allocated;
  78    otherwise, read-only cells will be allocated.  If no writable cells
  79    cannot be allocated, we will try to allocate unwritable cells
  80    instead, and print a message on stderr to that effect (if verbose_p).
  81  */
  82 extern void make_smooth_colormap (Display *dpy, Visual *visual,
  83                                   Colormap cmap,
  84                                   XColor *colors, int *ncolorsP,
  85                                   Bool allocate_p,
  86                                   Bool *writable_pP,
  87                                   Bool verbose_p);
  88
  89 /* Allocates a uniform colormap which touches each hue of the spectrum,
  90    evenly spaced.  The saturation and intensity are chosen randomly, but
  91    will be high enough to be visible.
  92
  93    If allocate_p is true, the colors will be allocated from the map;
  94    if enough colors can't be allocated, we will try for less, and the
  95    result will be returned to ncolorsP.  An error message will be
  96    printed on stderr (if verbose_p).
  97
  98    If *writable_pP is true, writable color cells will be allocated;
  99    otherwise, read-only cells will be allocated.  If no writable cells
 100    cannot be allocated, we will try to allocate unwritable cells
 101    instead, and print a message on stderr to that effect (if verbose_p).
 102  */
 103 extern void make_uniform_colormap (Display *dpy, Visual *visual,
 104                                    Colormap cmap,
 105                                    XColor *colors, int *ncolorsP,
 106                                    Bool allocate_p,
 107                                    Bool *writable_pP,
 108                                    Bool verbose_p);
 109
 110 /* Allocates a random colormap (the colors are unrelated to one another.)
 111    If `bright_p' is false, the colors will be completely random; if it is
 112    true, all of the colors will be bright enough to see on a black background.
 113
 114    If allocate_p is true, the colors will be allocated from the map;
 115    if enough colors can't be allocated, we will try for less, and the
 116    result will be returned to ncolorsP.  An error message will be
 117    printed on stderr (if verbose_p).
 118
 119    If *writable_pP is true, writable color cells will be allocated;
 120    otherwise, read-only cells will be allocated.  If no writable cells
 121    cannot be allocated, we will try to allocate unwritable cells
 122    instead, and print a message on stderr to that effect (if verbose_p).
 123  */
 124 extern void make_random_colormap (Display *dpy, Visual *visual,
 125                                   Colormap cmap,
 126                                   XColor *colors, int *ncolorsP,
 127                                   Bool bright_p,
 128                                   Bool allocate_p,
 129                                   Bool *writable_pP,
 130                                   Bool verbose_p);
 131
 132
 133 /* Assuming that the array of colors indicates the current state of a set
 134    of writable color cells, this rotates the contents of the array by
 135    `distance' steps, moving the colors of cell N to cell (N - distance).
 136  */
 137 extern void rotate_colors (Display *, Colormap,
 138                            XColor *, int ncolors, int distance);
 139
 140 #endif /* __COLORS_H__ */