Use SDL instead of GLUT.

Cribbed thoroughly from idr's stuff.

4 files changed, 118 insertions, 34 deletions

diff --git a/Makefile.am b/Makefile.am
index 0180cfc..67483dd 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,7 +1,7 @@
 AUTOMAKE_OPTIONS = foreign
 ACLOCAL_AMFLAGS = -I m4
 
-LDADD = $(PNG_LIBS) $(GL_LIBS) -lglut
+LDADD = $(PNG_LIBS) $(GL_LIBS)
 CFLAGS = $(PNG_CFLAGS) $(GL_CFLAGS) $(WARN_CFLAGS)
 
 bin_PROGRAMS = glass
diff --git a/configure.ac b/configure.ac
index 7c17e32..56f84ed 100644
--- a/configure.ac
+++ b/configure.ac
@@ -46,11 +46,11 @@ WARN_CFLAGS=""
 if test "x$GCC" = "xyes"; then
 	WARN_CFLAGS="-Wall -Wpointer-arith -Wstrict-prototypes \
 	-Wmissing-prototypes -Wmissing-declarations \
-	-Wnested-externs -fno-strict-aliasing"
+	-Wnested-externs -fno-strict-aliasing -Wno-switch-enum"
 fi
 AC_SUBST([WARN_CFLAGS])
 
-PKG_CHECK_MODULES(GL, [gl])
+PKG_CHECK_MODULES(GL, [gl sdl])
 GL_LIBS="$GL_LIBS -lGLEW"
 
 dnl libpng check, taken from cairo.  Yuck.
diff --git a/glass.c b/glass.c
index b890ee8..adaebae 100644
--- a/glass.c
+++ b/glass.c
@@ -1,5 +1,6 @@
 /*
  * Copyright © 2009 Eric Anholt
+ * Copyright © 2009 Ian D. Romanick
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -36,14 +37,10 @@
 #include <sys/stat.h>
 #include <getopt.h>
 
-#define GL_GLEXT_PROTOTYPES
-#include <GL/glew.h>
-#include <GL/glut.h>
-#include <GL/gl.h>
-#include <GL/glext.h>
-
 #include "glass.h"
 
+#include <SDL.h>
+
 #define DEFAULT_WIDTH	600
 #define DEFAULT_HEIGHT	700
 
@@ -88,6 +85,8 @@ static time_t start_tv_sec = 0;
 static float start_time, cur_time, last_fps_time = 0;
 static int no_multi_draw_arrays;
 static int frames = 0, last_fps_frames = 0;
+static SDL_Surface *sdl_surf = NULL;
+static GLboolean done = GL_FALSE;
 
 static double
 get_time_in_secs(void)
@@ -238,7 +237,7 @@ draw(void)
 		do_ring_drawelements();
 	}
 
-	glutSwapBuffers();
+	SDL_GL_SwapBuffers();
 	frames++;
 }
 
@@ -428,11 +427,14 @@ reshape(int width, int height)
 	win_width = width;
 	win_height = height;
 
+	sdl_surf = SDL_SetVideoMode(width, height, 0,
+				   SDL_OPENGL | SDL_RESIZABLE);
+	if (sdl_surf == NULL)
+		errx(1, "video mode set fail\n");
+
 	glMatrixMode(GL_PROJECTION);
 	glLoadIdentity();
 	gluPerspective(80, win_width / (float)win_height, 0.2, 40);
-
-	glutPostRedisplay();
 }
 
 static GLint
@@ -666,6 +668,10 @@ init(void)
 	GLuint vbo;
 	int sv;
 
+	reshape(DEFAULT_WIDTH, DEFAULT_HEIGHT);
+
+	glewInit();
+
 	if (!GLEW_VERSION_2_0)
 		errx(1, "Requires GL 2.0\n");
 	if (!GLEW_ARB_vertex_array_object)
@@ -710,8 +716,6 @@ init(void)
 
 	glUnmapBuffer(GL_ARRAY_BUFFER_ARB);
 
-	reshape(win_width, win_height);
-
 	free(verts);
 
 	load_program();
@@ -722,13 +726,30 @@ init(void)
 	heightmap_tex = load_texture_rgb("heightmap.png");
 }
 
+/**
+ * Push an event each time the timer callback fires.
+ */
+static uint32_t
+timer_callback(uint32_t interval, void *not_used)
+{
+	SDL_Event e;
+
+	(void) not_used;
+
+	e.type = SDL_USEREVENT;
+	e.user.code = 0;
+	e.user.data1 = NULL;
+	e.user.data2 = NULL;
+	SDL_PushEvent(&e);
+
+	return interval;
+}
+
 static void
 idle(void)
 {
 	cur_time = get_time_in_secs() - start_time;
 
-	glutPostRedisplay();
-
 	if (cur_time > last_fps_time + 5) {
 		printf("%d frames in %.2f secs: %.1f fps\n",
 		       frames - last_fps_frames,
@@ -741,14 +762,19 @@ idle(void)
 }
 
 static void
-key(unsigned char k, int x, int y)
+key(SDLKey sym)
 {
-	switch (k) {
+	switch (sym) {
 	case 'c':
 		load_program();
 		break;
-	case 27: /* escape */
-		exit(0);
+	case 'f':
+		SDL_WM_ToggleFullScreen(sdl_surf);
+		break;
+	case SDLK_ESCAPE:
+		done = GL_TRUE;
+		break;
+	default:
 		break;
 	}
 }
@@ -759,22 +785,73 @@ static void usage(char *program)
 	exit(1);
 }
 
+static void
+sdl_event(SDL_Event *event)
+{
+	static int shift_status = 0;
+
+	switch (event->type) {
+	case SDL_VIDEORESIZE:
+		reshape(event->resize.w, event->resize.h);
+		break;
+
+	case SDL_QUIT:
+		done = GL_TRUE;
+		break;
+
+	case SDL_KEYDOWN:
+		if ((event->key.keysym.sym == SDLK_RSHIFT) ||
+		    (event->key.keysym.sym == SDLK_LSHIFT)) {
+			shift_status++;
+		} else {
+			key(event->key.keysym.sym);
+		}
+		break;
+
+	case SDL_KEYUP:
+		if ((event->key.keysym.sym == SDLK_RSHIFT)
+		    || (event->key.keysym.sym == SDLK_LSHIFT)) {
+			shift_status--;
+		}
+
+		/* By clamping the shift status value to 0 we
+		 * prevent some bugs when the program is
+		 * started with one or both of the shift keys
+		 * held down.
+		 */
+		if (shift_status < 0) {
+			shift_status = 0;
+		}
+		break;
+
+
+	case SDL_MOUSEBUTTONDOWN:
+		break;
+	case SDL_MOUSEBUTTONUP:
+		break;
+	case SDL_MOUSEMOTION:
+		break;
+	case SDL_VIDEOEXPOSE:
+		break;
+	default:
+		if (event->type != SDL_USEREVENT) {
+			printf("event = 0x%04x\n", event->type);
+		}
+		break;
+	}
+}
+
 int main(int argc, char **argv)
 {
 	int i;
 
 	start_time = get_time_in_secs();
 
-	glutInit(&argc, argv);
-	glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
-	glutInitWindowPosition(0, 0);
-	glutInitWindowSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
-	glutCreateWindow("glass");
+	if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER) < 0)
+		errx(1, "sdl init fail");
+	atexit(SDL_Quit);
 
-	glutDisplayFunc(draw);
-	glutReshapeFunc(reshape);
-	glutKeyboardFunc(key);
-	glutIdleFunc(idle);
+	(void)SDL_AddTimer(10, timer_callback, NULL);
 
 	for (i = 1; i < argc; i++) {
 		if (strcmp(argv[i], "-nomultidraw") == 0)
@@ -783,10 +860,20 @@ int main(int argc, char **argv)
 			usage(argv[0]);
 	}
 
-	glewInit();
 	init();
 
-	glutMainLoop();
+	while (!done) {
+		SDL_Event event;
+
+		SDL_WaitEvent(&event);
+		do {
+			sdl_event(&event);
+
+		} while (SDL_PollEvent(&event));
+
+		idle();
+		draw();
+	}
 
 	return 0;
 }
diff --git a/glass.h b/glass.h
index 6d7579a..b84d5ae 100644
--- a/glass.h
+++ b/glass.h
@@ -27,9 +27,6 @@
 
 #define GL_GLEXT_PROTOTYPES
 #include <GL/glew.h>
-#include <GL/glut.h>
-#include <GL/gl.h>
-#include <GL/glext.h>
 
 /* matrix.c */
 void mult_m4_p4(float *result, const float *mat4, const float *point4);