// invertsection.fx
precision lowp float;

// User settings:
uniform float vFlip;
uniform float hFlip;

// Texturing:
varying vec2 vTex;
uniform sampler2D samplerBack;
uniform vec2 destStart;
uniform vec2 destEnd;

void main(void)
{
    vec2 tex = vTex;
    if (1.0 == hFlip) tex.s = 1.0 - tex.s;
    if (1.0 == vFlip) tex.t = 1.0 - tex.t;
    gl_FragColor = texture2D(samplerBack, mix(destStart, destEnd, tex));
}[/code:3qjc6yk9]

XML File:
[code:3qjc6yk9]<?xml version="1.0" encoding="UTF-8" ?>
<c2effect>
     <id>invertsection</id>
     <name>Invert Section</name>
     <category>Distortion</category>
     <description>Invert a subsection of the screen about x-axis or y-axis.</description>
     <author>Edwin</author>

     <!-- Settings -->
     <extend-box-horizontal>0</extend-box-horizontal>
     <extend-box-vertical>0</extend-box-vertical>
     <blends-background>true</blends-background>
     <cross-sampling>true</cross-sampling>
     <animated>false</animated>
     
     <!-- Parameters -->
     <parameters>
          <param>
              <name>Vertical Flip</name>
              <description>Set to 1 if you want to flip vertically.</description>
              <type>float</type>
              <initial>0</initial>
              <uniform>vFlip</uniform>
          </param>
          <param>
              <name>Horizontal Flip</name>
              <description>Set to 1 if you want to flip horizontally.</description>
              <type>float</type>
              <initial>0</initial>
              <uniform>hFlip</uniform>
          </param>
     </parameters>
</c2effect>[/code:3qjc6yk9]Edwin2013-11-21 04:02:29