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//
// libavg - Media Playback Engine.
// Copyright (C) 2003-2011 Ulrich von Zadow
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser 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
//
// Current versions can be found at www.libavg.de
//
uniform sampler2D u_Texture;
uniform bool u_bIsLast;
#ifndef FRAGMENT_ONLY
varying vec2 v_TexCoord;
varying vec4 v_Color;
#endif
void main(void)
{
float minAlpha = 1.0;
float dx = dFdx(v_TexCoord.x);
float dy = dFdy(v_TexCoord.y);
for (float y = -1.0; y <= 1.0; ++y) {
for (float x = -1.0; x <= 1.0; ++x) {
float a = texture2D(u_Texture, v_TexCoord+vec2(x*dx,y*dy)).a;
minAlpha = min(minAlpha, a);
}
}
vec4 tex = texture2D(u_Texture, v_TexCoord);
if (u_bIsLast) {
gl_FragColor = vec4(tex.rgb*minAlpha, minAlpha);
} else {
gl_FragColor = vec4(tex.rgb, minAlpha);
}
}
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