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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#version 130
/*precision mediump float;*/
void main() {
vec2 tex_mod = mod(gl_FragCoord, 2).xy;
bool bLeft = (tex_mod.x > 0.0) && (tex_mod.x < 1.0);
bool bTop = (tex_mod.y > 0.0) && (tex_mod.y < 1.0);
// horrors - where is the XOR operator ?
if ((bTop && bLeft) || (!bTop && !bLeft))
gl_FragColor = vec4(255,255,255,0);
else
gl_FragColor = vec4(0,0,0,0);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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