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/* font test -- based on extext */
/* Specifically, this tests alpha fonts blending into backgrounds compared
* to solid text with transparent background.
*/
#include <time.h>
#include <math.h>
#include <string.h>
#include "allegro.h"
#include "alleggl.h"
int main() {
FONT *demofont;
DATAFILE *dat;
allegro_init();
install_allegro_gl();
allegro_gl_clear_settings();
allegro_gl_set(AGL_COLOR_DEPTH, 32);
allegro_gl_set(AGL_WINDOWED, TRUE);
allegro_gl_set(AGL_DOUBLEBUFFER, 1);
allegro_gl_set(AGL_SUGGEST, AGL_DOUBLEBUFFER | AGL_COLOR_DEPTH
| AGL_WINDOWED);
if (set_gfx_mode(GFX_OPENGL, 640, 480, 0, 0)) {
allegro_message("Error initializing OpenGL!\n");
return -1;
}
install_keyboard();
install_timer();
/* Load font palette first, then font itself */
dat = load_datafile_object ("demofont.dat", "PAL");
if (!dat) {
set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
allegro_message("Error loading demofont.dat#PAL\n");
return -1;
}
set_palette ((RGB *)dat->dat);
unload_datafile_object (dat);
dat = load_datafile_object ("demofont.dat", "FONT");
if (!dat) {
set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
allegro_message("Error loading demofont.dat#FONT\n");
return -1;
}
demofont = allegro_gl_convert_allegro_font_ex((FONT*)dat->dat,
AGL_FONT_TYPE_TEXTURED, 16.0, GL_ALPHA8);
unload_datafile_object(dat);
if (!demofont) {
set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
allegro_message("Unable to convert font!\n");
return -1;
}
/* Setup OpenGL the way we want */
glEnable(GL_TEXTURE_2D);
glViewport(0, 0, SCREEN_W, SCREEN_H);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, 1, 0, 1, -1, 1);
glMatrixMode(GL_MODELVIEW);
do {
int x, y;
glLoadIdentity();
/* Draw the background */
for (y = 0; y < 4; y++) {
for (x = 0; x < 4; x++) {
glColor3f ((y&1), (x&1), ((y&2)^(x&2))/2);
glBegin (GL_QUADS);
glVertex2f (x*0.25, y*0.25);
glVertex2f (x*0.25, (y+1)*0.25);
glVertex2f ((x+1)*0.25, (y+1)*0.25);
glVertex2f ((x+1)*0.25, y*0.25);
glEnd();
}
}
/* Draw the text on top */
glScalef (0.1, 0.1, 0.1);
/* First, draw the text alpha blended */
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
allegro_gl_printf(demofont, 1, 8, 0, makeacol(255,255,255,255),
"Hello World!");
glBlendFunc(GL_ONE, GL_ZERO);
glDisable(GL_BLEND);
/* Now just draw it solid with transparent background */
glEnable(GL_ALPHA_TEST);
glAlphaFunc(GL_GREATER, 0.5f);
allegro_gl_printf(demofont, 1, 5, 0, makeacol(255,255,255,255),
"Hello World!");
glDisable(GL_ALPHA_TEST);
allegro_gl_flip();
rest(2);
} while (!keypressed());
/* Clean up and exit */
allegro_gl_destroy_font(demofont);
TRACE("Font Destroyed");
return 0;
}
END_OF_MAIN()
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