OpenGL Hello World

diff --git a/src/Makefile.am b/src/Makefile.am
index 7605c8c084af7d72841f1a72497071fc9a201b72..cca3efd5515bd094c6034880c356b4c4bc49a2af 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,5 +1,5 @@
 bin_PROGRAMS = aweather
 
-aweather_SOURCES  = aweather.c
+aweather_SOURCES  = aweather.c aweather.h cube.c cube.h
 aweather_CPPFLAGS = @PACKAGE_CFLAGS@
 aweather_LDADD    = @PACKAGE_LIBS@

diff --git a/src/aweather.c b/src/aweather.c
index a2c33c371758c0e60696475b2cf4bfd94095eb50..c96cf190f7ff1a4c3c2551c17d1c52bf43a2c580 100644 (file)
--- a/src/aweather.c
+++ b/src/aweather.c
@@ -1,41 +1,67 @@
 #include <config.h>
 #include <gtk/gtk.h>
+#include <gtk/gtkgl.h>
+#include <gdk/gdkkeysyms.h>
 
-static void hello(GtkWidget *widget, gpointer data)
+#include "cube.h"
+
+static void destroy(GtkWidget *widget, gpointer data)
 {
-       g_print("Hello World\n");
+       gtk_main_quit();
 }
 
 static gboolean delete_event(GtkWidget *widget, GdkEvent *event, gpointer data)
 {
-       g_print("delete event occurred\n");
+       destroy(widget, data);
        return FALSE;
 }
 
-static void destroy(GtkWidget *widget, gpointer data)
+static gboolean key_press(GtkWidget *widget, GdkEventKey *event, gpointer data)
 {
-       gtk_main_quit();
+       if (event->keyval == GDK_q)
+               destroy(widget, data);
 }
 
 int main(int argc, char *argv[])
 {
-       GtkWidget *window;
-       GtkWidget *button;
 
        gtk_init(&argc, &argv);
+       gtk_gl_init(&argc, &argv);
+
+       /* Set up window */
+       GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+       gtk_window_set_default_size(GTK_WINDOW(window), 800, 600);
+       g_signal_connect(G_OBJECT(window), "delete-event",    G_CALLBACK(delete_event), NULL);
+       g_signal_connect(G_OBJECT(window), "delete-event",    G_CALLBACK(delete_event), NULL);
+       g_signal_connect(G_OBJECT(window), "key-press-event", G_CALLBACK(key_press),    NULL);
+
+       /* Set up layout */
+       GtkWidget *vbox = gtk_vbox_new(FALSE, 0);
+       gtk_container_add(GTK_CONTAINER(window), vbox);
 
-       window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
-       g_signal_connect(G_OBJECT(window), "delete_event", G_CALLBACK(delete_event), NULL);
-       g_signal_connect(G_OBJECT(window), "destroy",      G_CALLBACK(destroy),      NULL);
+       /* Set up menu bar */
+       GtkWidget *menu                = gtk_menu_bar_new();
+       GtkWidget *menu_file           = gtk_menu_item_new_with_label("File");
+       GtkWidget *menu_file_menu      = gtk_menu_new();
+       GtkWidget *menu_file_menu_quit = gtk_menu_item_new_with_label("Quit");
+       gtk_box_pack_start(GTK_BOX(vbox), menu, FALSE, FALSE, 0);
+       gtk_menu_shell_append(GTK_MENU_SHELL(menu), menu_file);
+       gtk_menu_item_set_submenu(GTK_MENU_ITEM(menu_file), menu_file_menu);
+       gtk_menu_shell_append(GTK_MENU_SHELL(menu_file_menu), menu_file_menu_quit);
+       g_signal_connect(G_OBJECT(menu_file_menu_quit), "activate", G_CALLBACK(destroy), NULL);
 
-       gtk_container_set_border_width(GTK_CONTAINER(window), 10);
-       button = gtk_button_new_with_label("Hello World");
-       g_signal_connect(        G_OBJECT(button), "clicked", G_CALLBACK(hello),              NULL);
-       g_signal_connect_swapped(G_OBJECT(button), "clicked", G_CALLBACK(gtk_widget_destroy), G_OBJECT(window));
+       /* Set up darwing area */
+       GtkWidget *drawing = gtk_drawing_area_new();
+       gtk_box_pack_start(GTK_BOX(vbox), drawing, TRUE, TRUE, 0);
+       //gtk_widget_set_events(drawing, GDK_EXPOSURE_MASK); // needed?
+       GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(GDK_GL_MODE_RGB | GDK_GL_MODE_DEPTH | GDK_GL_MODE_DOUBLE);
+       if (!glconfig) g_assert_not_reached();
+       if (!gtk_widget_set_gl_capability(drawing, glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE)) g_assert_not_reached();
+       g_signal_connect(drawing, "configure-event", G_CALLBACK(configure), NULL);
+       g_signal_connect(drawing, "expose-event",    G_CALLBACK(expose),    NULL);
+       g_timeout_add(1000/60, rotate, drawing);
 
-       gtk_container_add(GTK_CONTAINER(window), button);
-       gtk_widget_show(button);
-       gtk_widget_show(window);
+       gtk_widget_show_all(window);
        gtk_main();
 
        return 0;

diff --git a/src/cube.c b/src/cube.c
new file mode 100644 (file)
index 0000000..9465938
--- /dev/null
+++ b/src/cube.c
@@ -0,0 +1,145 @@
+#include <config.h>
+#include <gtk/gtk.h>
+#include <gtk/gtkgl.h>
+#include <gdk/gdkkeysyms.h>
+#include <GL/gl.h>
+#include <math.h>
+
+float boxv[][3] = {
+       { -0.5, -0.5, -0.5 },
+       {  0.5, -0.5, -0.5 },
+       {  0.5,  0.5, -0.5 },
+       { -0.5,  0.5, -0.5 },
+       { -0.5, -0.5,  0.5 },
+       {  0.5, -0.5,  0.5 },
+       {  0.5,  0.5,  0.5 },
+       { -0.5,  0.5,  0.5 }
+};
+#define ALPHA 0.5
+
+static float ang = 30.;
+
+gboolean expose (GtkWidget *da, GdkEventExpose *event, gpointer user_data)
+{
+       GdkGLContext *glcontext = gtk_widget_get_gl_context (da);
+       GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable (da);
+
+       // g_print (" :: expose\n");
+
+       if (!gdk_gl_drawable_gl_begin (gldrawable, glcontext))
+       {
+               g_assert_not_reached ();
+       }
+
+       /* draw in here */
+       glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+       glPushMatrix();
+       
+       glRotatef (ang, 1, 0, 1);
+
+       glShadeModel(GL_FLAT);
+
+       glBegin (GL_LINES);
+       glColor3f (1., 0., 0.);
+       glVertex3f (0., 0., 0.);
+       glVertex3f (1., 0., 0.);
+       glEnd ();
+       
+       glBegin (GL_LINES);
+       glColor3f (0., 1., 0.);
+       glVertex3f (0., 0., 0.);
+       glVertex3f (0., 1., 0.);
+       glEnd ();
+       
+       glBegin (GL_LINES);
+       glColor3f (0., 0., 1.);
+       glVertex3f (0., 0., 0.);
+       glVertex3f (0., 0., 1.);
+       glEnd ();
+
+       glBegin(GL_LINES);
+       glColor3f (1., 1., 1.);
+       glVertex3fv(boxv[0]);
+       glVertex3fv(boxv[1]);
+       
+       glVertex3fv(boxv[1]);
+       glVertex3fv(boxv[2]);
+       
+       glVertex3fv(boxv[2]);
+       glVertex3fv(boxv[3]);
+       
+       glVertex3fv(boxv[3]);
+       glVertex3fv(boxv[0]);
+       
+       glVertex3fv(boxv[4]);
+       glVertex3fv(boxv[5]);
+       
+       glVertex3fv(boxv[5]);
+       glVertex3fv(boxv[6]);
+       
+       glVertex3fv(boxv[6]);
+       glVertex3fv(boxv[7]);
+       
+       glVertex3fv(boxv[7]);
+       glVertex3fv(boxv[4]);
+       
+       glVertex3fv(boxv[0]);
+       glVertex3fv(boxv[4]);
+       
+       glVertex3fv(boxv[1]);
+       glVertex3fv(boxv[5]);
+       
+       glVertex3fv(boxv[2]);
+       glVertex3fv(boxv[6]);
+       
+       glVertex3fv(boxv[3]);
+       glVertex3fv(boxv[7]);
+       glEnd();
+
+       glPopMatrix ();
+
+       if (gdk_gl_drawable_is_double_buffered (gldrawable))
+               gdk_gl_drawable_swap_buffers (gldrawable);
+
+       else
+               glFlush ();
+
+       gdk_gl_drawable_gl_end (gldrawable);
+
+       return TRUE;
+}
+
+gboolean configure(GtkWidget *da, GdkEventConfigure *event, gpointer user_data)
+{
+       GdkGLContext *glcontext = gtk_widget_get_gl_context (da);
+       GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable (da);
+
+       if (!gdk_gl_drawable_gl_begin (gldrawable, glcontext))
+       {
+               g_assert_not_reached ();
+       }
+
+       glLoadIdentity();
+       glViewport (0, 0, da->allocation.width, da->allocation.height);
+       glOrtho (-10,10,-10,10,-20050,10000);
+       glEnable (GL_BLEND);
+       glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+       glScalef (10., 10., 10.);
+       
+       gdk_gl_drawable_gl_end (gldrawable);
+
+       return TRUE;
+}
+
+gboolean rotate (gpointer user_data)
+{
+       GtkWidget *da = GTK_WIDGET (user_data);
+
+       ang++;
+
+       gdk_window_invalidate_rect (da->window, &da->allocation, FALSE);
+       gdk_window_process_updates (da->window, FALSE);
+
+       return TRUE;
+}

diff --git a/src/cube.h b/src/cube.h
new file mode 100644 (file)
index 0000000..4ba6a69
--- /dev/null
+++ b/src/cube.h
@@ -0,0 +1,8 @@
+#ifndef CUBE_H
+#define CUBE_H
+
+gboolean expose(GtkWidget *da, GdkEventExpose *event, gpointer user_data);
+gboolean configure(GtkWidget *da, GdkEventConfigure *event, gpointer user_data);
+gboolean rotate(gpointer user_data);
+
+#endif