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// [config]
// expect_result: pass
// glsl_version: 1.10
//
// [end config]
/*
* GStreamer
* Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#extension GL_ARB_texture_rectangle : enable
uniform sampler2DRect tex;
uniform float width, height;
void main () {
vec2 tex_size = vec2 (width, height);
vec2 texturecoord = gl_TexCoord[0].xy;
vec2 normcoord;
/* little trick with normalized coords to obtain a circle */
normcoord = texturecoord / tex_size.x - tex_size / tex_size.x;
float r = length(normcoord);
float phi = atan(normcoord.y, normcoord.x);
r = clamp (r, 0.0, 0.5); /* is there a way to do this without polars? */
normcoord.x = r * cos(phi);
normcoord.y = r * sin(phi);
texturecoord = (normcoord + tex_size/tex_size.x) * tex_size.x;
vec4 color = texture2DRect (tex, texturecoord);
gl_FragColor = color;
}
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