8 #include "aweather-gui.h"
10 static gboolean expose_start(GtkWidget *da, GdkEventExpose *event, gpointer user_data)
12 g_message("opengl:expose_start");
13 GdkGLContext *glcontext = gtk_widget_get_gl_context(da);
14 GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(da);
16 if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext)) {
17 g_assert_not_reached();
21 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
24 /* Plugins run stuff here */
25 static gboolean expose_end(GtkWidget *da, GdkEventExpose *event, gpointer user_data)
27 g_message("opengl:expose_end\n");
29 GdkGLDrawable *gldrawable = gdk_gl_drawable_get_current();
31 if (gdk_gl_drawable_is_double_buffered(gldrawable))
32 gdk_gl_drawable_swap_buffers(gldrawable);
36 gdk_gl_drawable_gl_end(gldrawable);
40 static gboolean configure_start(GtkWidget *da, GdkEventConfigure *event, gpointer user_data)
42 g_message("opengl:configure_start");
43 GdkGLContext *glcontext = gtk_widget_get_gl_context(da);
44 GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(da);
46 if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
47 g_assert_not_reached();
50 double width = da->allocation.width;
51 double height = da->allocation.height;
52 double dist = 500*1000; // 500 km
55 glViewport(0, 0, width, height);
57 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
58 glClearColor(0.8f, 0.8f, 1.0f, 0.0f);
60 /* Tessellation, "finding intersecting triangles" */
61 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
62 /* http://www.opengl.org/wiki/Alpha_Blending */
63 glAlphaFunc(GL_GREATER,0.1);
64 glEnable(GL_ALPHA_TEST);
68 glDepthFunc(GL_LEQUAL);
69 glEnable(GL_DEPTH_TEST);
72 glMatrixMode(GL_PROJECTION);
74 double rad = atan(height/2*1000.0/dist); // 1px = 1000 meters
75 double deg = (rad*180)/M_PI;
76 gluPerspective(deg*2, width/height, dist-20, dist+20);
78 /* Camera position? */
79 glMatrixMode(GL_MODELVIEW);
81 glTranslatef(0.0, 0.0, -dist);
82 //glRotatef(-45, 1, 0, 0);
87 static gboolean configure_end(GtkWidget *da, GdkEventConfigure *event, gpointer user_data)
89 g_message("opengl:configure_end");
90 GdkGLDrawable *gldrawable = gdk_gl_drawable_get_current();
91 gdk_gl_drawable_gl_end(gldrawable);
95 gboolean opengl_init(AWeatherGui *gui)
97 GtkDrawingArea *drawing = aweather_gui_get_drawing(gui);
99 GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
100 GDK_GL_MODE_RGBA | GDK_GL_MODE_DEPTH |
101 GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
103 g_error("Failed to create glconfig");
104 if (!gtk_widget_set_gl_capability(GTK_WIDGET(drawing), glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
105 g_error("GL lacks required capabilities");
107 /* Set up OpenGL Stuff */
108 g_signal_connect (drawing, "configure-event", G_CALLBACK(configure_start), NULL);
109 g_signal_connect_after(drawing, "configure-event", G_CALLBACK(configure_end), NULL);
110 g_signal_connect (drawing, "expose-event", G_CALLBACK(expose_start), NULL);
111 g_signal_connect_after(drawing, "expose-event", G_CALLBACK(expose_end), NULL);