src/opengl/util/fast_painter.glsl
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Fri, 19 Feb 2010 23:40:16 +0200
branchRCL_3
changeset 4 3b1da2848fc7
parent 0 1918ee327afb
permissions -rw-r--r--
Revision: 201003 Kit: 201007

// fast painter for composition modes which can be implemented with blendfuncs

uniform sampler2D mask_texture;
uniform vec2 inv_mask_size;
uniform vec2 mask_offset;
uniform vec4 mask_channel;

float mask()
{
    return dot(mask_channel, texture2D(mask_texture, (gl_FragCoord.xy + mask_offset) * inv_mask_size));
}

void main()
{
    // combine clip and coverage channels
    float mask_alpha = mask();

    gl_FragColor = brush() * mask_alpha;
}