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/* Allegro-AllegroGL interface example */
#include <stdio.h>
#include <math.h>
#include "allegro.h"
#include "alleggl.h"
#include "running.h"
#ifndef M_PI
#define M_PI 3.1415926535897932384626433832795
#endif
volatile int chrono = 0;
void the_timer(void) {
chrono++;
} END_OF_FUNCTION(the_timer);
int main() {
BITMAP *texture;
GLuint tex[6];
int i = 0;
int frame_count = 0, frame_count_time = 0;
float fps_rate = 0.0;
FONT *f;
int old_depth;
/* Init Allegro */
allegro_init();
install_allegro_gl();
install_keyboard();
install_mouse();
/* Set up an OpenGL screen mode */
allegro_gl_clear_settings();
allegro_gl_set(AGL_COLOR_DEPTH, 32);
allegro_gl_set(AGL_Z_DEPTH, 24);
allegro_gl_set(AGL_WINDOWED, TRUE);
allegro_gl_set(AGL_DOUBLEBUFFER, 1);
allegro_gl_set(AGL_RENDERMETHOD, 1);
allegro_gl_set(AGL_SUGGEST, AGL_COLOR_DEPTH | AGL_DOUBLEBUFFER
| AGL_RENDERMETHOD | AGL_Z_DEPTH | AGL_WINDOWED);
if (set_gfx_mode(GFX_OPENGL, 640, 480, 0, 0)) {
allegro_message("Error setting OpenGL graphics mode:\n%s\n"
"Allegro GL error : %s\n",
allegro_error, allegro_gl_error);
return -1;
}
/* Set up a timer that ticks every 5 ms */
LOCK_FUNCTION(the_timer);
LOCK_VARIABLE(chrono);
install_int(the_timer, 5);
/* Let's load the mysha image in various color depths.
*/
old_depth = bitmap_color_depth(screen);
for (i = 0; i < 3; i++) {
char name[256];
/* Load mysha */
set_color_depth((i + 2) * 8);
texture = load_bitmap("mysha.pcx", NULL);
if (!texture) {
set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
allegro_message("Unable to load mysha.pcx - did you copy Allegro's here?\n");
return -3;
}
tex[i * 2] = allegro_gl_make_masked_texture(texture);
tex[i * 2 + 1] = allegro_gl_make_texture(texture);
/* Just to verify that the load was successful, save the images to disk
* so they can be checked manually.
*/
uszprintf(name, sizeof(name), "mysha%i.bmp", i);
save_bitmap(name, texture, NULL);
destroy_bitmap(texture);
}
set_color_depth(old_depth);
/* Convert the Allegro font */
f = allegro_gl_convert_allegro_font(font, AGL_FONT_TYPE_TEXTURED, 16.0);
/* Now display everything */
/* Setup OpenGL the way we want */
glEnable(GL_TEXTURE_2D);
glEnable(GL_BLEND);
glViewport(0, 0, SCREEN_W, SCREEN_H);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-1.0, 1.0, -1.0, 1.0, 1, 60.0);
/* Set culling mode - not that we have anything to cull */
glEnable(GL_CULL_FACE);
glFrontFace(GL_CCW);
glMatrixMode(GL_MODELVIEW);
/* Flush keyboard buffer */
while (keypressed()) readkey();
/* Main rendering loop */
do {
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
/* Draw all quads */
for (i = 0; i < 6; i++) {
glLoadIdentity();
glTranslatef(-10.0 + 4 * (i & 1), -4.0 * (i / 2 - 1), -10.0);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glBindTexture(GL_TEXTURE_2D, tex[i]);
glBegin(GL_QUADS);
glTexCoord2f(0, 0);
glVertex2f(0, 0);
glTexCoord2f(1, 0);
glVertex2f(4, 0);
glTexCoord2f(1, 1);
glVertex2f(4, 4);
glTexCoord2f(0, 1);
glVertex2f(0, 4);
glEnd();
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
allegro_gl_printf(f, 0, 3.9, 0.1, makecol(255, 255, 255),
"%i bpp", (i/2+2) * 8);
glBlendFunc(GL_ONE, GL_ZERO);
}
/* Draw some lines and triangles using Allegro */
allegro_gl_set_allegro_mode();
/* Vertices of triangles should be entered carefully : OpenGL culls
* back faces...
* Therefore, according to glFrontFace(GL_CCW), vertices are given
* in counterclockwise order.
*/
triangle(screen, 470 + (int)(sin(-chrono / 100.0) * 150),
250 - (int)(cos(-chrono / 100.0) * 150),
470 + (int)(sin(-chrono / 100.0 + M_PI * 4 / 3) * 150),
250 - (int)(cos(-chrono / 100.0 + M_PI * 4 / 3) * 150),
470 + (int)(sin(-chrono / 100.0 + M_PI * 2 / 3) * 150),
250 - (int)(cos(-chrono / 100.0 + M_PI * 2 / 3) * 150),
makecol(0, 0, 255));
triangle(screen, 470 + (int)(sin(chrono / 100.0) * 150),
250 - (int)(cos(chrono / 100.0) * 150),
470 + (int)(sin(chrono / 100.0 + M_PI * 4 / 3) * 150),
250 - (int)(cos(chrono / 100.0 + M_PI * 4 / 3) * 150),
470 + (int)(sin(chrono / 100.0 + M_PI * 2 / 3) * 150),
250 - (int)(cos(chrono / 100.0 + M_PI * 2 / 3) * 150),
makecol(0, 255, 0));
for (i = 0; i < 6; i++) {
hline(screen, 320, 100 + (chrono % 50) + 50 * i, 620,
makecol(255, 0, 0));
}
for (i = 0; i < 6; i++) {
vline(screen, 320 + (chrono % 50) + 50 * i, 100, 400,
makecol(255, 0, 0));
}
for (i = 0; i < 6; i++) {
line(screen, 620 - (chrono % 50) - 50 * i, 400,
620, 400 - (chrono % 50) - 50 * i, makecol(255, 0, 0));
line(screen, 320, 400 - (chrono % 50) - 50 * i,
620 - (chrono % 50) - 50 * i, 100, makecol(255, 0, 0));
}
rect(screen, 320, 100, 620, 400, makecol(255, 255, 0));
/* draw mouse */
triangle(screen,
mouse_x + 20 + (int)(sin(chrono / 100.0) * 15),
mouse_y - (int)(cos(chrono / 100.0) * 15) + 7,
mouse_x + 20 + (int)(sin(chrono / 100.0 + M_PI * 4 / 3) * 15),
mouse_y - (int)(cos(chrono / 100.0 + M_PI * 4 / 3) * 15) + 7,
mouse_x + 20 + (int)(sin(chrono / 100.0 + M_PI * 2 / 3) * 15),
mouse_y - (int)(cos(chrono / 100.0 + M_PI * 2 / 3) * 15) + 7,
makecol(255, 255, 0));
triangle(screen, mouse_x, mouse_y, mouse_x + 25, mouse_y + 15,
mouse_x + 35, mouse_y, makecol(255, 0, 0));
allegro_gl_unset_allegro_mode();
/* Compute and display the framerate */
frame_count++;
if (frame_count >= 20) {
if (chrono > frame_count_time) {
fps_rate = frame_count * 200.0 / (chrono - frame_count_time);
}
else {
fps_rate = 200;
}
frame_count -= 20;
frame_count_time = chrono;
}
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
allegro_gl_printf(f, 0, 0, 0, makecol(255, 255, 255),
"FPS: %.2f", fps_rate);
glBlendFunc(GL_ONE, GL_ZERO);
/* Resets the current color to its initial value
* That must be done in order to reset alpha to 255
*/
glColor4ub(255, 255, 255, 255);
allegro_gl_flip();
rest(2);
} while (!keypressed());
destroy_font(f);
return 0;
}
END_OF_MAIN()
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