Gray-Chart.dctl

DEFINE_UI_PARAMS(timeGamma, Timeline Gamma, DCTLUI_COMBO_BOX, 0, {recGam, linGam}, {Scene,Linear})

__DEVICE__ float lin_to_rec(float x) {
	if(x < .0018f) return 4.5f * x;
	else return 1.099f * _powf(x,0.45f) - 0.099f;
}


__DEVICE__ float3 transform(int p_Width, int p_Height, int p_X, int p_Y, float p_R, float p_G, float p_B)
{

	int p_Size = p_Width / 3;
	if(p_X >= p_Size * 2) { //White
		p_R = 1.0f;
		p_G = 1.0f;
		p_B = 1.0f;
	} else if( p_X >= p_Size) { // 18% Gray
		p_R = 0.18f;
		p_G = 0.18f;
		p_B = 0.18f;
	} else { // Black
		p_R = 0.0f;
		p_G = 0.0f;
		p_B = 0.0f;
	}

	if(timeGamma == recGam) {
		p_R = lin_to_rec(p_R);
		p_G = lin_to_rec(p_G);
		p_B = lin_to_rec(p_B);
	}

	return make_float3(p_R,p_G,p_B);
}