3 * Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
21 #extension GL_ARB_texture_rectangle : enable
22 uniform sampler2DRect base;
23 uniform sampler2DRect blend;
24 uniform sampler2DRect alpha;
25 uniform float final_width, final_height;
26 uniform float base_width, base_height;
28 uniform float blend_width, blend_height;
29 uniform float alpha_width, alpha_height;
32 vec2 base_scale = vec2 (base_width, base_height) / vec2 (final_width, final_height);
34 vec2 blend_scale = vec2 (blend_width, blend_height) / vec2 (final_width, final_height);
35 vec2 alpha_scale = vec2 (alpha_width, alpha_height) / vec2 (final_width, final_height);
38 vec4 basecolor = texture2DRect (base, gl_TexCoord[0].st * base_scale);
39 vec4 blendcolor = texture2DRect (blend, gl_TexCoord[0].st);
40 vec4 alphacolor = texture2DRect (alpha, gl_TexCoord[0].st);
41 gl_FragColor = (alphacolor * blendcolor) + (1.0 - alphacolor) * basecolor;