Shader

#version 120

#define MAX_NUM_CAMS 8
varying vec3 location;
varying vec3 location_obj;
uniform mat4 viewMat;
uniform int numCameras;
uniform sampler2D texSampler[MAX_NUM_CAMS];
uniform sampler2D weightSampler[MAX_NUM_CAMS];

void main()
{
    int i;
    float sumw = 0.0;
    float camw[MAX_NUM_CAMS];
    vec3 colour = vec3(0,0,0);
    vec4 p = vec4(location, 1.0);
    vec4 p_obj = vec4(location_obj, 1.0);
    vec4 tc = viewMat * p_obj;

    camw[0] = texture2DProj(weightSampler[0],tc).r;
    camw[1] = texture2DProj(weightSampler[1],tc).r;
    camw[2] = texture2DProj(weightSampler[2],tc).r;
    camw[3] = texture2DProj(weightSampler[3],tc).r;
    camw[4] = texture2DProj(weightSampler[4],tc).r;
    camw[5] = texture2DProj(weightSampler[5],tc).r;
    camw[6] = texture2DProj(weightSampler[6],tc).r;
    camw[7] = texture2DProj(weightSampler[7],tc).r;

    vec4 texCoord0 = gl_TextureMatrix[0] * p;
    vec4 texColour0 = texture2DProj(texSampler[0],texCoord0);
    vec4 texCoord1 = gl_TextureMatrix[1] * p;
    vec4 texColour1 = texture2DProj(texSampler[1],texCoord1);
    vec4 texCoord2 = gl_TextureMatrix[2] * p;
    vec4 texColour2 = texture2DProj(texSampler[2],texCoord2);
    vec4 texCoord3 = gl_TextureMatrix[3] * p;
    vec4 texColour3 = texture2DProj(texSampler[3],texCoord3);
    vec4 texCoord4 = gl_TextureMatrix[4] * p;
    vec4 texColour4 = texture2DProj(texSampler[4],texCoord4);
    vec4 texCoord5 = gl_TextureMatrix[5] * p;
    vec4 texColour5 = texture2DProj(texSampler[5],texCoord5);
    vec4 texCoord6 = gl_TextureMatrix[6] * p;
    vec4 texColour6 = texture2DProj(texSampler[6],texCoord6);
    vec4 texCoord7 = gl_TextureMatrix[7] * p;
    vec4 texColour7 = texture2DProj(texSampler[7],texCoord7);


    i = 0;

    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 1;
    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 2;
    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 3;
    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 4;
    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 5;

    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 6;
    if (i<numCameras)
    {
        sumw += camw[i];
    }
    i = 7;
    if (i<numCameras)
    {
        sumw += camw[i];
    }



    if (sumw<=0.0)
    {
        discard;
    }
    else
    {
        i = 0;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour0.rgb*w;
        }
        i = 1;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour1.rgb*w;
        }
        i = 2;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour2.rgb*w;
        }
        i = 3;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour3.rgb*w;
        }
        i = 4;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour4.rgb*w;
        }
        i = 5;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour5.rgb*w;
        }
        i = 6;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour6.rgb*w;
        }
        i = 7;
        if (i<numCameras && sumw>0.0)
        {
            float w = camw[i] / sumw;
            if (w>1.0) w = 1.0;
            colour += texColour7.rgb*w;
        }


        gl_FragColor = vec4(colour, 1);
    }
}