ab.flowrepos.jxs

<jittershader name="flowrepos">
    <description>
    high-quality relative distortion based on hsflow output position map
    </description>
    <param name="amt" type="vec2" default="1. 1." />
    <param name="scale" type="vec4" default="1. 1. 1. 1." />
    <param name="bias" type="vec4" default="0. 0. 0. 0." />
    <param name="tex0" type="int" default="0" />
    <param name="tex1" type="int" default="1" />
    <language name="glsl" version="1.0">
        <bind param="amt" program="fp" />
        <bind param="scale" program="fp" />
        <bind param="bias" program="fp" />
        <bind param="tex0" program="fp" />
        <bind param="tex1" program="fp" />
        <program name="vp" type="vertex" source="sh.passthrudim.vp.glsl" />
        <program name="fp" type="fragment">
<![CDATA[

// Andrew Benson - andrewb@cycling74.com
// Copyright 2009

//setup for 2 texture
varying vec2 texcoord0;
varying vec2 texcoord1;
varying vec2 texdim0;
varying vec2 texdim1;
uniform vec2 amt;
uniform vec4 scale;
uniform vec4 bias;
uniform vec2 boundmode;
uniform sampler2DRect tex0;
uniform sampler2DRect tex1;


void main()
{
    vec4 look = texture2DRect(tex1,texcoord1);//sample repos texture
    vec2 offs = vec2(look.y-look.x,look.w-look.z)*amt;
    vec2 coord = offs+texcoord0;//relative coordinates
    //coord = mod(coord,texdim0);
    vec4 repos = texture2DRect(tex0, coord);
    
    // output texture
    gl_FragColor = repos*scale+bias;
}
]]>
        </program>
    </language>
</jittershader>