main.c

   1 /*******************************************************************************
   2 **3456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789
   3 **      10        20        30        40        50        60        70        80
   4 **
   5 ** program:
   6 **    gl-cairo-cube
   7 **
   8 ** author:
   9 **    Mirco "MacSlow" Mueller <macslow@bangang.de>
  10 **
  11 ** copyright (C) Mirco Mueller, July 2006
  12 **
  13 ** notes:
  14 **    Simple example demonstrating how one could use cairo for generating
  15 **    dynamic texture-mapping with OpenGL. Intended to be run on a composited
  16 **    desktop (e.g. compiz, xcompmgr) with proper a OpenGL-implementation. I put
  17 **    this program under the terms of the "GNU General Public License". If you
  18 **    don't know what that means take a look a here...
  19 **
  20 **        http://www.gnu.org/licenses/licenses.html#GPL
  21 **
  22 *******************************************************************************/
  23
  24 #include <gtk/gtk.h>
  25 #include <gtk/gtkgl.h>
  26 #include <GL/glut.h>
  27
  28 #include "geometry.h"
  29 #include "events.h"
  30 #include "cairo-rendering.h"
  31
  32 GtkWidget*                      g_pWindow = NULL;
  33 GdkGLConfig*            g_pGlConfig = NULL;
  34 GtkWidget*                      g_pDrawingArea = NULL;
  35 guint                           g_uiDrawHandlerId = 0;
  36 gint                            g_iWindowWidth;
  37 gint                            g_iWindowHeight;
  38 GLfloat                         g_afAngle[3] = {0.0f, 0.0f, 0.0f};
  39 gint                            g_iFrames = 0;
  40 GLfloat                         g_fScale = 1.0f;
  41 GTimer*                         g_pTimerId = NULL;
  42 gboolean                        g_bKeepRunning = TRUE;
  43 gdouble                         g_fLastTimeStamp = 0.0f;
  44 gdouble                         g_fCurrentTimeStamp = 0.0f;
  45 gdouble                         g_fLastFullSecond = 0.0f;
  46 gboolean                        g_bLMBPressed = FALSE;
  47 gboolean                        g_bRMBPressed = FALSE;
  48 GLuint                          g_auiColorBuffer[2];
  49 gdouble                         g_fCurrentX;
  50 gdouble                         g_fCurrentY;
  51 gdouble                         g_fDeltaX;
  52 gdouble                         g_fDeltaY;
  53 gdouble                         g_fLastX;
  54 gdouble                         g_fLastY;
  55 gint                            g_iWidth = 1;
  56 gint                            g_iHeight = 1;
  57 GLfloat                         g_fAlpha = 1.0f;
  58 gboolean                        g_bInitialized = FALSE;
  59 cairo_surface_t*        g_pCairoSurface[2];
  60 cairo_t*                        g_pCairoContext[2];
  61 guchar*                         g_pucSurfaceData[2];
  62 gulong                          g_ulMilliSeconds = 0L;
  63 Line                            g_lineOne;
  64 Line                            g_lineTwo;
  65
  66 int main (int argc, char** argv)
  67 {
  68         g_lineOne.start.fX = 0.1f;
  69         g_lineOne.start.fY = 0.2f;
  70         g_lineOne.start.bGrowX = TRUE;
  71         g_lineOne.start.bGrowY = TRUE;
  72         g_lineOne.start.fStepX = 0.025f;
  73         g_lineOne.start.fStepY = 0.02f;
  74         g_lineOne.start.fLowerLimitX = 0.1f;
  75         g_lineOne.start.fUpperLimitX = 0.9f;
  76         g_lineOne.start.fLowerLimitY = 0.1f;
  77         g_lineOne.start.fUpperLimitY = 0.9f;
  78
  79         g_lineOne.end.fX = 0.5f;
  80         g_lineOne.end.fY = 0.7f;
  81         g_lineOne.end.bGrowX = TRUE;
  82         g_lineOne.end.bGrowY = FALSE;
  83         g_lineOne.end.fStepX = 0.025f;
  84         g_lineOne.end.fStepY = 0.01f;
  85         g_lineOne.end.fLowerLimitX = 0.1f;
  86         g_lineOne.end.fUpperLimitX = 0.9f;
  87         g_lineOne.end.fLowerLimitY = 0.1f;
  88         g_lineOne.end.fUpperLimitY = 0.9f;
  89
  90         g_lineTwo.start.fX = 0.75f;
  91         g_lineTwo.start.fY = 0.1f;
  92         g_lineTwo.start.bGrowX = FALSE;
  93         g_lineTwo.start.bGrowY = TRUE;
  94         g_lineTwo.start.fStepX = 0.01f;
  95         g_lineTwo.start.fStepY = 0.025f;
  96         g_lineTwo.start.fLowerLimitX = 0.1f;
  97         g_lineTwo.start.fUpperLimitX = 0.9f;
  98         g_lineTwo.start.fLowerLimitY = 0.1f;
  99         g_lineTwo.start.fUpperLimitY = 0.9f;
 100
 101         g_lineTwo.end.fX = 0.8f;
 102         g_lineTwo.end.fY = 0.8f;
 103         g_lineTwo.end.bGrowX = FALSE;
 104         g_lineTwo.end.bGrowY = FALSE;
 105         g_lineTwo.end.fStepX = 0.01f;
 106         g_lineTwo.end.fStepY = 0.01f;
 107         g_lineTwo.end.fLowerLimitX = 0.1f;
 108         g_lineTwo.end.fUpperLimitX = 0.9f;
 109         g_lineTwo.end.fLowerLimitY = 0.1f;
 110         g_lineTwo.end.fUpperLimitY = 0.9f;
 111
 112         /* init gtk+, GL and glut */
 113         gtk_init (&argc,&argv);
 114         gtk_gl_init (&argc,&argv);
 115         glutInit (&argc, argv);
 116
 117         /* setup GL-context */
 118         g_pGlConfig = gdk_gl_config_new_by_mode (GDK_GL_MODE_RGB        |
 119                                                                                          GDK_GL_MODE_ALPHA      |
 120                                                                                          GDK_GL_MODE_DEPTH      |
 121                                                                                          GDK_GL_MODE_DOUBLE);
 122
 123         if (!g_pGlConfig)
 124         {
 125                 g_print ("Could not setup GL-context!\n");
 126                 return 1;
 127         }
 128
 129         /* create window and hook up event-handlers */
 130         g_pWindow = gtk_window_new (GTK_WINDOW_TOPLEVEL);
 131         if (!g_pWindow)
 132         {
 133                 g_print ("Could not create gtk+-window!\n");
 134                 return 2;
 135         }
 136
 137         gtk_widget_add_events (g_pWindow,
 138                                                    GDK_POINTER_MOTION_MASK |
 139                                                    GDK_BUTTON_PRESS_MASK |
 140                                                    GDK_BUTTON_RELEASE_MASK);
 141
 142         g_signal_connect (G_OBJECT (g_pWindow),
 143                                           "delete-event",
 144                                           G_CALLBACK (delete_handler),
 145                                           NULL);
 146         g_signal_connect (G_OBJECT (g_pWindow),
 147                                           "button-press-event",
 148                                           G_CALLBACK (button_handler),
 149                                           NULL);
 150         g_signal_connect (G_OBJECT (g_pWindow),
 151                                           "button-release-event",
 152                                           G_CALLBACK (button_handler),
 153                                           NULL);
 154         g_signal_connect (G_OBJECT (g_pWindow),
 155                                           "screen-changed",
 156                                           G_CALLBACK (screen_changed_handler),
 157                                           NULL);
 158         g_signal_connect (G_OBJECT (g_pWindow),
 159                                           "scroll-event",
 160                                           G_CALLBACK (scroll_handler),
 161                                           NULL);
 162         g_signal_connect (G_OBJECT (g_pWindow),
 163                                           "key-press-event",
 164                                           G_CALLBACK (key_press_handler),
 165                                           NULL);
 166
 167         g_pDrawingArea = gtk_drawing_area_new ();
 168         if (!g_pDrawingArea)
 169         {
 170                 g_print ("Could not create drawing-area!\n");
 171                 return 3;
 172         }
 173
 174         g_iWindowWidth = g_iWidth = 512;
 175         g_iWindowHeight = g_iHeight = 512;
 176         gtk_widget_set_size_request (g_pDrawingArea, g_iWindowWidth, g_iWindowHeight);
 177         gtk_widget_set_gl_capability (g_pDrawingArea,
 178                                                                   g_pGlConfig,
 179                                                                   NULL,
 180                                                                   TRUE,
 181                                                                   GDK_GL_RGBA_TYPE);
 182
 183         g_signal_connect_after (G_OBJECT (g_pDrawingArea),
 184                                                         "realize",
 185                                                         G_CALLBACK (realize_handler),
 186                                                         NULL);
 187         g_signal_connect (G_OBJECT (g_pDrawingArea),
 188                                           "configure-event",
 189                                           G_CALLBACK (configure_handler),
 190                                           NULL);
 191         g_signal_connect (G_OBJECT (g_pDrawingArea),
 192                                           "expose-event",
 193                                           G_CALLBACK (expose_handler),
 194                                           NULL);
 195         g_signal_connect (G_OBJECT (g_pWindow),
 196                                           "motion-notify-event",
 197                                           G_CALLBACK (motion_notify_handler),
 198                                           (gpointer) g_pDrawingArea);
 199
 200         gtk_container_add (GTK_CONTAINER (g_pWindow), g_pDrawingArea);
 201         gtk_widget_show (g_pDrawingArea);
 202         gtk_window_set_resizable (GTK_WINDOW (g_pWindow), FALSE);
 203         gtk_widget_set_app_paintable (g_pWindow, TRUE);
 204         gtk_window_set_decorated (GTK_WINDOW (g_pWindow), FALSE);
 205         screen_changed_handler (g_pWindow, NULL, NULL);
 206         gtk_widget_show (g_pWindow);
 207
 208         /* create cairo-surface/context to act as OpenGL-texture */
 209         g_pucSurfaceData[0] = g_malloc0 (4 * g_iWidth * g_iHeight);
 210         g_pucSurfaceData[1] = g_malloc0 (4 * g_iWidth * g_iHeight);
 211         if (g_pucSurfaceData[0] && g_pucSurfaceData[1])
 212         {
 213                 g_pCairoSurface[0] = cairo_image_surface_create_for_data (g_pucSurfaceData[0],
 214                                                                                                                                   CAIRO_FORMAT_ARGB32,
 215                                                                                                                                   g_iWidth,
 216                                                                                                                                   g_iHeight,
 217                                                                                                                                   4 * g_iWidth);
 218                 g_pCairoSurface[1] = cairo_image_surface_create_for_data (g_pucSurfaceData[1],
 219                                                                                                                                   CAIRO_FORMAT_ARGB32,
 220                                                                                                                                   g_iWidth,
 221                                                                                                                                   g_iHeight,
 222                                                                                                                                   4 * g_iWidth);
 223
 224                 g_pCairoContext[0] = cairo_create (g_pCairoSurface[0]);
 225                 g_pCairoContext[1] = cairo_create (g_pCairoSurface[1]);
 226                 g_bInitialized = TRUE;
 227         }
 228
 229         /* force a refresh-rate of 20 Hz */
 230         g_uiDrawHandlerId = g_timeout_add (50,
 231                                                                            (GSourceFunc) draw_handler,
 232                                                                            g_pDrawingArea);
 233
 234         /* register timer used by fps-counter */
 235         g_pTimerId = g_timer_new ();
 236
 237         /* enter event-loop */
 238         gtk_main ();
 239
 240         /* clear resources before exit */
 241         glDeleteTextures (2, g_auiColorBuffer);
 242         if (g_pucSurfaceData[0])
 243                 g_free (g_pucSurfaceData[0]);
 244         if (g_pucSurfaceData[1])
 245                 g_free (g_pucSurfaceData[1]);
 246
 247         return 0;
 248 }