Pan.dctl

// Pan
// Snaps image to left or right side if gap present, or symmetrically aligns image if gap on both sides


__DEVICE__ float3 transform(int p_Width, int p_Height, int p_X, int p_Y, __TEXTURE__ p_TexR, __TEXTURE__ p_TexG, __TEXTURE__ p_TexB)
{
	
	int pan = 0;
	int panL = 0;
	int panR = 0;

	for(int i = 0; i < p_Width / 2; ++i) {
    if(_tex2D(p_TexR, i, p_Height / 2) == 0.0f && _tex2D(p_TexG, i, p_Height / 2) == 0.0f && _tex2D(p_TexB, i, p_Height / 2) == 0.0f){
    panL += 1;}}
    
    for(int i = p_Width / 2; i < p_Width; ++i) {
    if(_tex2D(p_TexR, i, p_Height / 2) == 0.0f && _tex2D(p_TexG, i, p_Height / 2) == 0.0f && _tex2D(p_TexB, i, p_Height / 2) == 0.0f){
    panR += 1;}}
    
    pan = panL > 0 && panR > 0 ? (panL - panR) / 2 : panL - panR;
    
    const float r = _tex2D(p_TexR, p_X + pan, p_Y);
    const float g = _tex2D(p_TexG, p_X + pan, p_Y);
    const float b = _tex2D(p_TexB, p_X + pan, p_Y);
    
    return make_float3(r, g, b);
}