glBindTexture (GL_TEXTURE_2D, mp->texture);
check_gl_error ("texture init");
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGBA, xi->width, xi->height, 0, GL_RGBA,
glBindTexture (GL_TEXTURE_2D, mp->texture);
check_gl_error ("texture init");
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGBA, xi->width, xi->height, 0, GL_RGBA,