static void ogl_update_transformation(ALLEGRO_DISPLAY* disp,
ALLEGRO_BITMAP *target)
{
if (disp->flags & ALLEGRO_PROGRAMMABLE_PIPELINE) {
#ifdef ALLEGRO_CFG_SHADER_GLSL
GLint loc = disp->ogl_extras->varlocs.projview_matrix_loc;
ALLEGRO_TRANSFORM projview;
al_copy_transform(&projview, &target->transform);
al_compose_transform(&projview, &target->proj_transform);
al_copy_transform(&disp->projview_transform, &projview);
if (disp->ogl_extras->program_object > 0 && loc >= 0) {
_al_glsl_set_projview_matrix(loc, &disp->projview_transform);
}
#endif
} else {
glMatrixMode(GL_PROJECTION);
glLoadMatrixf((float *)target->proj_transform.m);
glMatrixMode(GL_MODELVIEW);
glLoadMatrixf((float *)target->transform.m);
}
if (target->parent) {
ALLEGRO_BITMAP_EXTRA_OPENGL *ogl_extra = target->parent->extra;
/* glViewport requires the bottom-left coordinate of the corner. */
glViewport(target->xofs, ogl_extra->true_h - (target->yofs + target->h), target->w, target->h);
} else {
glViewport(0, 0, target->w, target->h);
}
}
static bool glsl_use_shader(ALLEGRO_SHADER *shader, ALLEGRO_DISPLAY *display,
bool set_projview_matrix_from_display)
{
ALLEGRO_SHADER_GLSL_S *gl_shader;
GLuint program_object;
GLenum err;
if (!(display->flags & ALLEGRO_OPENGL)) {
return false;
}
gl_shader = (ALLEGRO_SHADER_GLSL_S *)shader;
program_object = gl_shader->program_object;
glGetError(); /* clear error */
glUseProgram(program_object);
err = glGetError();
if (err != GL_NO_ERROR) {
ALLEGRO_WARN("glUseProgram(%u) failed: %s\n", program_object,
_al_gl_error_string(err));
display->ogl_extras->program_object = 0;
return false;
}
display->ogl_extras->program_object = program_object;
/* Copy variable locations. */
display->ogl_extras->varlocs = gl_shader->varlocs;
/* Optionally set projview matrix. We skip this when it is known that the
* matrices in the display are out of date and are about to be clobbered
* itself.
*/
if (set_projview_matrix_from_display) {
_al_glsl_set_projview_matrix(
display->ogl_extras->varlocs.projview_matrix_loc, &display->projview_transform);
}
return true;
}
