//**************************************************************************/
// Copyright 2012 Autodesk, Inc.  
// All rights reserved.
// Use of this software is subject to the terms of the Autodesk license 
// agreement provided at the time of installation or download, or which 
// otherwise accompanies this software in either electronic or hard copy form.   
//**************************************************************************/

#include "Common.cgh"

// Color texture. Assumed to be 4 channel
texture gColorTex : SourceTexture
<
    string UIName = "Color Texture";
>;
// Color texture sampler.
sampler2D gColorSampler = sampler_state
{
    Texture = <gColorTex>;
    MinFilter = Point;
    MagFilter = Point;
    MipFilter = Point;
};

// Disable alpha output.
bool gDisableAlpha;

// Depth texture. Assumed to be 1 channel normalized between 0 and 1
texture gDepthTex : SourceTexture2
<
    string UIName = "Depth Texture";
>;
// Depth texture sampler.
sampler2D gDepthSampler = sampler_state
{
    Texture = <gDepthTex>;
    MinFilter = Point;
    MagFilter = Point;
    MipFilter = Point;
};


// Pixel shader outputs both color and depth
struct PS_OUTPUT
{
    float4 color : COLOR0;
    float  depth : DEPTH;
};

// Pixel shader for color + depth
//
PS_OUTPUT PS_BlitColorDepth(VS_TO_PS_ScreenQuad In)
{
	PS_OUTPUT outputStruct;

	// Output color
	//
	In.UV.y = 1.0f - In.UV.y;
	float4 output = tex2D(gColorSampler, In.UV); 
	if (gDisableAlpha)
	{
	    outputStruct.color = float4( output.xyz, 1.0 );
	}
	else
	{
	    outputStruct.color = output;
	}

	// Output depth
	//
	float4 outputDepth = tex2D(gDepthSampler, In.UV); 
	outputStruct.depth = outputDepth.r;

	return outputStruct;
}

// Debug depth to color. Assumes a R32 single channel texture.
//
float4 PS_BlitDepthToColor(VS_TO_PS_ScreenQuad In) : COLOR0
{
	In.UV.y = 1.0f - In.UV.y;
	float4 outputDepth = tex2D(gDepthSampler, In.UV); 
	return float4(outputDepth.rrr, 1.0f);
}

// The main technique
technique Main
{
    pass p0
    {
        VertexProgram = compile glslv VS_ScreenQuad();
        FragmentProgram  = compile glslf PS_BlitColorDepth();
    }
}

// Debug by putting depth to color
technique DepthToColor
{
    pass p0
    {
        VertexProgram = compile glslv VS_ScreenQuad();
        FragmentProgram  = compile glslf PS_BlitDepthToColor();
    }
}