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#include <SDL.h>
#include <GL/gl.h>
#include <sdl-freetype.h>
#include <sdl-freetype-opengl.h>
#include <sdl-ft.h>
#include <stdio.h>
#define TEXT "sdl freetype OpenGL render"
int
main(int argc, char *argv[])
{
SDL_Surface * screen;
Uint8 video_bpp;
Uint32 videoflags;
int done;
SDL_Event event;
float alpha, step;
sdl_freetype_font_t * font;
sdl_freetype_glyph_render_t * render;
sdl_freetype_text_extents_t extents;
/* Initialize SDL */
if (SDL_Init (SDL_INIT_VIDEO) < 0)
goto errquit0;
videoflags = SDL_HWSURFACE;
videoflags |= SDL_OPENGL;
video_bpp = 32;
/* Set 640x480 video mode */
screen = SDL_SetVideoMode (640, 480, video_bpp, videoflags);
if (!screen)
goto errquit0;
font = sdl_ft_create_font ("sans", 20,
SDL_FT_WEIGHT_NORMAL, SDL_FT_SLANT_NORMAL, 96);
if (!font)
goto errquit0;
render = sdl_freetype_opengl_render_create ();
if (!render)
goto errquit1;
sdl_freetype_font_set_render (font, render);
glMatrixMode (GL_PROJECTION) ;
glLoadIdentity ();
glOrtho (0, 640, 480, 0, -1.0, 1.0);
glMatrixMode (GL_MODELVIEW);
glLoadIdentity ();
glEnable (GL_TEXTURE_2D);
glClearColor (0.8f, 0.8f, 0.8f, 0.0f);
alpha = 1.0f;
step = -0.01;
/* Wait for a keystroke */
done = 0;
while (!done) {
/* Check for events */
while (SDL_PollEvent (&event)) {
switch (event.type) {
case SDL_MOUSEBUTTONDOWN:
break;
case SDL_KEYDOWN:
case SDL_QUIT:
done = 1;
break;
default:
break;
}
}
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
sdl_freetype_font_utf8_extents (font, &extents, TEXT, -1);
glTranslatef ((640 - extents.width) / 2 - extents.x_bearing,
(480 - extents.height) / 2 + extents.y_bearing, 0);
sdl_freetype_font_show_utf8 (font, NULL, 255, 0, 0, alpha * 255,
0, 0, TEXT, -1);
SDL_GL_SwapBuffers();
alpha += step;
if (alpha < 0.0f) {
alpha = 0.0f;
step = -step;
} else if (alpha > 1.0f) {
alpha = 1.0f;
step = -step;
}
SDL_Delay(20);
}
errquit1:
sdl_freetype_font_destroy (font);
sdl_freetype_fini ();
errquit0:
SDL_Quit();
return 0;
}
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