Implement filter with GPUImage2

[ChernyshenkoTaras]

I'm working on implementation this filter with GPUImage 2. Here is small demo. However I stuck on applying all filters to CompositingFilter.

From what I can see in my implementation interpolation of image and toneCurvedImage in some reason doesn't work. In this shader

    varying highp vec2 textureCoordinate;
    varying highp vec2 textureCoordinate2;
    varying highp vec2 textureCoordinate3;

    uniform sampler2D inputImageTexture;
    uniform sampler2D inputImageTexture2;
    uniform sampler2D inputImageTexture3;

    void main() {
        highp vec4 image = texture2D(inputImageTexture, textureCoordinate);
        highp vec4 toneCurvedImage = texture2D(inputImageTexture2, textureCoordinate2);
        highp vec4 mask = texture2D(inputImageTexture3, textureCoordinate3);
        gl_FragColor = vec4(mix(image.rgb,toneCurvedImage.rgb, 1.0 - mask.b),1.0);
    }

and I can't understand why, because it all the same as yours(which is perfectly works!). I will appreciate if you will help me understand what I'm doing wrong.

[ChernyshenkoTaras]

Ah. I posted it and almost instantly found an issue. GPUImage2 doesn't has implementation of ToneCurveFilter, so I used this one from PR. However seems it has bug and it doesn't work in my filter. For now my solution was to use lookup table with predefined tone curves.