-public:
-
- /**
- * Create an empty OverlayEffect handle.
- */
- OverlayEffect();
-
- /**
- * @brief Destructor
- *
- * This is non-virtual since derived Handle types must not contain data or virtual methods.
- */
- ~OverlayEffect();
+ // (Target > 0.5) * (1 - (1-2*(Target-0.5)) * (1-Blend)) + (Target <= 0.5) * ((2*Target) * Blend)
+ const char* OVERLAY_FRAGMENT_SHADER_SOURCE =
+ "void main()\n"
+ "{\n"
+ " lowp vec4 target = texture2D(sTexture, vTexCoord);\n"
+ " lowp vec4 overlay = texture2D(sEffect, vTexCoord);\n"
+ " if ( length( target.rgb ) > 0.5 )\n"
+ " {\n"
+ " gl_FragColor = vec4( mix( target.rgb, 1.0 - ( 1.0 - 2.0 * ( target.rgb - 0.5 ) ) * ( 1.0 - overlay.rgb ), overlay.a ), min( 1.0, target.a + overlay.a ) );\n"
+ " }\n"
+ " else\n"
+ " {\n"
+ " gl_FragColor = vec4( mix( target.rgb, 2.0 * target.rgb * overlay.rgb, overlay.a ), target.a + overlay.a );\n"
+ " }\n"
+ "}\n";