void Shader::setVal( const std::string& name, float val )
{
al_set_shader_float(name.c_str(),val);
}
int main(int argc, char **argv)
{
ALLEGRO_DISPLAY *display;
ALLEGRO_BITMAP *bmp, *tmp;
ALLEGRO_SHADER *horz_shader;
ALLEGRO_SHADER *vert_shader;
al_init();
al_install_keyboard();
al_init_image_addon();
display = al_create_display(480, 320);
bmp = al_load_bitmap("glow.png");
ALLEGRO_BITMAP *bg = al_load_bitmap("bg.png");
tmp = al_create_bitmap(
al_get_bitmap_width(bmp),
al_get_bitmap_height(bmp)
);
horz_shader = al_create_shader(ALLEGRO_SHADER_GLSL);
vert_shader = al_create_shader(ALLEGRO_SHADER_GLSL);
al_attach_shader_source(
horz_shader,
ALLEGRO_VERTEX_SHADER,
glsl_vertex_source
);
al_attach_shader_source(
horz_shader,
ALLEGRO_PIXEL_SHADER,
glsl_pixel_source_horz
);
al_link_shader(horz_shader);
al_attach_shader_source(
vert_shader,
ALLEGRO_VERTEX_SHADER,
glsl_vertex_source
);
al_attach_shader_source(
vert_shader,
ALLEGRO_PIXEL_SHADER,
glsl_pixel_source_vert
);
al_link_shader(vert_shader);
ALLEGRO_COLOR white = al_map_rgb(255, 255, 255);
al_set_blender(ALLEGRO_ADD, ALLEGRO_ALPHA, ALLEGRO_INVERSE_ALPHA, white);
ALLEGRO_VERTEX *v;
v = new ALLEGRO_VERTEX[6*4];
v[0].x = 0;
v[0].y = 320;
v[0].z = 0;
v[0].u = 0;
v[0].v = 0;
v[0].color = white;
v[1].x = 0;
v[1].y = 0;
v[1].z = 0;
v[1].u = 0;
v[1].v = 1;
v[1].color = white;
v[2].x = 480;
v[2].y = 0;
v[2].z = 0;
v[2].u = 1;
v[2].v = 1;
v[2].color = white;
v[3].x = 0;
v[3].y = 320;
v[3].z = 0;
v[3].u = 0;
v[3].v = 0;
v[3].color = white;
v[4].x = 480;
v[4].y = 0;
v[4].z = 0;
v[4].u = 1;
v[4].v = 1;
v[4].color = white;
v[5].x = 480;
v[5].y = 320;
v[5].z = 0;
v[5].u = 1;
v[5].v = 0;
v[5].color = white;
al_set_shader_vertex_array(horz_shader, &v[0].x, sizeof(ALLEGRO_VERTEX));
al_set_shader_color_array(horz_shader, (unsigned char *)&v[0].color, sizeof(ALLEGRO_VERTEX));
al_set_shader_texcoord_array(horz_shader, &v[0].u, sizeof(ALLEGRO_VERTEX));
al_set_shader_vertex_array(vert_shader, &v[0].x, sizeof(ALLEGRO_VERTEX));
al_set_shader_color_array(vert_shader, (unsigned char *)&v[0].color, sizeof(ALLEGRO_VERTEX));
al_set_shader_texcoord_array(vert_shader, &v[0].u, sizeof(ALLEGRO_VERTEX));
float radius = 1;
float rinc = 4;
while (1) {
al_set_target_bitmap(tmp);
al_clear_to_color(al_map_rgba(0, 0, 0,0));
ALLEGRO_KEYBOARD_STATE s;
al_get_keyboard_state(&s);
if (al_key_down(&s, ALLEGRO_KEY_ESCAPE))
break;
radius += rinc;
if (rinc > 0 && radius >= 25) {
rinc = -rinc;
}
else if (rinc < 0 && radius < 1) {
rinc = -rinc;
}
al_set_shader_sampler(horz_shader, "t", bmp, 0);
al_set_shader_float(horz_shader, "img_width", al_get_bitmap_width(bmp));
al_set_shader_float(horz_shader, "radius", radius);
al_use_shader(horz_shader, true);
al_draw_bitmap(bmp, 0, 0, 0);
al_use_shader(horz_shader, false);
al_set_target_bitmap(al_get_backbuffer());
al_draw_bitmap(bg, 0, 0, 0);
al_set_blender(ALLEGRO_ADD, ALLEGRO_ONE, ALLEGRO_ONE, white);
al_set_shader_sampler(vert_shader, "t", tmp, 0);
al_set_shader_float(vert_shader, "img_height", al_get_bitmap_height(bmp));
al_set_shader_float(vert_shader, "radius", radius);
al_use_shader(vert_shader, true);
al_draw_bitmap(tmp, 0, 0, 0);
al_use_shader(vert_shader, false);
al_set_blender(ALLEGRO_ADD, ALLEGRO_ALPHA, ALLEGRO_INVERSE_ALPHA, white);
al_draw_bitmap(bmp, 0, 0, 0);
al_flip_display();
al_rest(0.016);
}
al_save_bitmap("bgxx.png", bg);
al_save_bitmap("tmpxx.png", tmp);
return 0;
}