src/zoom_frame.c

   1 /*
   2  * This program is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU General Public License
   4  * as published by the Free Software Foundation; either version 2
   5  * of the License, or (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  15  *
  16  * See the COPYING file for license information.
  17  *
  18  * Guillaume Chazarain <guichaz@yahoo.fr>
  19  */
  20
  21 /************************************
  22  * The zoom frame with funky colors *
  23  ************************************/
  24
  25 #include <gtk/gtkgl.h>
  26
  27 #include "gliv.h"
  28 #include "zoom_frame.h"
  29 #include "options.h"
  30 #include "rendering.h"
  31 #include "matrix.h"
  32
  33 extern rt_struct *rt;
  34 extern GtkWidget *gl_widget;
  35
  36 /* Dimensions of the zoom frame. */
  37 static gint zoom_frame_x, zoom_frame_y;
  38 static gint zoom_frame_width, zoom_frame_height;
  39
  40 static gboolean zoom_frame_cleared = FALSE;
  41
  42 void draw_zoom_frame(gboolean draw)
  43 {
  44     /*
  45      * We keep the coordinates of the previous
  46      * frame to erase it with a XOR.
  47      */
  48     static gint x = 0;
  49     static gint y = 0;
  50     static gint width = 0;
  51     static gint height = 0;
  52     static GdkGC *gc = NULL;
  53     GdkDrawable *d;
  54
  55     d = gl_widget->window;
  56     if (gc == NULL) {
  57         /* First time. */
  58         gc = gdk_gc_new(d);
  59         gdk_gc_set_foreground(gc, &(gl_widget->style->white));
  60         gdk_gc_set_function(gc, GDK_XOR);
  61     }
  62
  63     if (draw)
  64         /* Erase the previous frame. */
  65         gdk_draw_rectangle(d, gc, FALSE, x, y, width, height);
  66
  67     /* Update saved coordinates. */
  68     x = zoom_frame_x;
  69     y = zoom_frame_y;
  70     width = zoom_frame_width;
  71     height = zoom_frame_height;
  72
  73     if (draw) {
  74         /* Draw the new frame. */
  75         gdk_draw_rectangle(d, gc, FALSE, x, y, width, height);
  76
  77         zoom_frame_cleared = FALSE;
  78
  79         gdk_gl_drawable_wait_gdk(gtk_widget_get_gl_drawable(gl_widget));
  80     }
  81 }
  82
  83 void set_zoom_frame(gint x, gint y, gint width, gint height)
  84 {
  85     if (width < 0) {
  86         zoom_frame_x = x + width;
  87         zoom_frame_width = -width;
  88     } else {
  89         zoom_frame_x = x;
  90         zoom_frame_width = width;
  91     }
  92
  93     if (height < 0) {
  94         zoom_frame_y = y + height;
  95         zoom_frame_height = -height;
  96     } else {
  97         zoom_frame_y = y;
  98         zoom_frame_height = height;
  99     }
 100 }
 101
 102 void clear_zoom_frame(void)
 103 {
 104     if (zoom_frame_cleared == FALSE) {
 105         set_zoom_frame(-1, -1, 0, 0);
 106         draw_zoom_frame(FALSE);
 107         zoom_frame_cleared = TRUE;
 108     }
 109 }
 110
 111 void zoom_frame(void)
 112 {
 113     gfloat x, y, zoom;
 114
 115     if (zoom_frame_width == 0 || zoom_frame_height == 0) {
 116         /* To avoid division by zero. */
 117         set_zoom_frame(-1, -1, 0, 0);
 118         draw_zoom_frame(TRUE);
 119         return;
 120     }
 121
 122     zoom = MIN((gfloat) rt->wid_size->width / zoom_frame_width,
 123                (gfloat) rt->wid_size->height / zoom_frame_height);
 124
 125     x = zoom_frame_x + zoom_frame_width / 2.0;
 126     y = zoom_frame_y + zoom_frame_height / 2.0;
 127
 128     /* zoom. */
 129     matrix_zoom(zoom, x, y);
 130
 131     /* center. */
 132     matrix_move(rt->wid_size->width / 2.0 - x, rt->wid_size->height / 2.0 - y);
 133
 134     refresh(REFRESH_IMAGE | REFRESH_STATUS | APPEND_HISTORY);
 135 }