path: root/LibOVR/Src/CAPI/D3D1X/CAPI_D3D1X_DistortionRenderer.cpp

/************************************************************************************

Filename    :   CAPI_D3D1X_DistortionRenderer.cpp
Content     :   Experimental distortion renderer
Created     :   November 11, 2013
Authors     :   Volga Aksoy, Michael Antonov, Shariq Hashme

Copyright   :   Copyright 2014 Oculus VR, LLC All Rights reserved.

Licensed under the Oculus VR Rift SDK License Version 3.2 (the "License"); 
you may not use the Oculus VR Rift SDK except in compliance with the License, 
which is provided at the time of installation or download, or which 
otherwise accompanies this software in either electronic or hard copy form.

You may obtain a copy of the License at

http://www.oculusvr.com/licenses/LICENSE-3.2 

Unless required by applicable law or agreed to in writing, the Oculus VR SDK 
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

************************************************************************************/

#include "CAPI_D3D1X_DistortionRenderer.h"

#include "../../OVR_CAPI_D3D.h"
#include "../CAPI_HMDState.h"
#include "../../Kernel/OVR_Color.h"

namespace OVR { namespace CAPI { namespace D3D_NS {

#include "Shaders/Distortion_vs.h"
#include "Shaders/Distortion_vs_refl.h"
#include "Shaders/Distortion_ps.h"
#include "Shaders/Distortion_ps_refl.h"
#include "Shaders/DistortionChroma_vs.h"
#include "Shaders/DistortionChroma_vs_refl.h"
#include "Shaders/DistortionChroma_ps.h"
#include "Shaders/DistortionChroma_ps_refl.h"
#include "Shaders/DistortionTimewarp_vs.h"
#include "Shaders/DistortionTimewarp_vs_refl.h"
#include "Shaders/DistortionTimewarpChroma_vs.h"
#include "Shaders/DistortionTimewarpChroma_vs_refl.h"
#include "Shaders/DistortionCS2x2.h"
#include "Shaders/DistortionCS2x2_refl.h"

#include "Shaders/SimpleQuad_vs.h"
#include "Shaders/SimpleQuad_vs_refl.h"
#include "Shaders/SimpleQuad_ps.h"
#include "Shaders/SimpleQuad_ps_refl.h"

#include <initguid.h>
DEFINE_GUID(IID_OVRDXGISwapchain, 0x868f9b4f, 0xe427, 0x46ed, 0xb0, 0x94, 0x66, 0xd1, 0x3b, 0xb, 0x48, 0xf7);

// Distortion pixel shader lookup.
//  Bit 0: Chroma Correction
//  Bit 1: Timewarp

enum {
    DistortionVertexShaderBitMask = 3,
    DistortionVertexShaderCount   = DistortionVertexShaderBitMask + 1,
    DistortionPixelShaderBitMask  = 1,
    DistortionPixelShaderCount    = DistortionPixelShaderBitMask + 1,
};

struct PrecompiledShader
{
    const unsigned char* ShaderData;
    size_t ShaderSize;
    const ShaderBase::Uniform* ReflectionData;
    size_t ReflectionSize;
};

// Do add a new distortion shader use these macros (with or w/o reflection)
#define PCS_NOREFL(shader) { shader, sizeof(shader), NULL, 0 }
#define PCS_REFL__(shader) { shader, sizeof(shader), shader ## _refl, sizeof( shader ## _refl )/sizeof(*(shader ## _refl)) }


static PrecompiledShader DistortionVertexShaderLookup[DistortionVertexShaderCount] =
{
    PCS_REFL__(Distortion_vs),
    PCS_REFL__(DistortionChroma_vs),
    PCS_REFL__(DistortionTimewarp_vs),
    PCS_REFL__(DistortionTimewarpChroma_vs),
};

static PrecompiledShader DistortionPixelShaderLookup[DistortionPixelShaderCount] =
{
    PCS_NOREFL(Distortion_ps),
    PCS_REFL__(DistortionChroma_ps)
};

enum
{
    DistortionComputeShader2x2           = 0,
    DistortionComputeShader2x2Pentile,
    DistortionComputeShaderCount
};
static PrecompiledShader DistortionComputeShaderLookup[DistortionComputeShaderCount] =
{
    PCS_REFL__(DistortionCS2x2)
};



void DistortionShaderBitIndexCheck()
{
    OVR_COMPILER_ASSERT(ovrDistortionCap_Chromatic == 1);
    OVR_COMPILER_ASSERT(ovrDistortionCap_TimeWarp  == 2);
}



struct DistortionVertex         // Must match the VB description DistortionMeshVertexDesc
{
    Vector2f ScreenPosNDC;
    Vector2f TanEyeAnglesR;
    Vector2f TanEyeAnglesG;
    Vector2f TanEyeAnglesB;
    Color    Col;
};

struct DistortionComputePin     // Must match the ones declared in DistortionCS*.csh
{
    Vector2f TanEyeAnglesR;
    Vector2f TanEyeAnglesG;
    Vector2f TanEyeAnglesB;
    Color Col;
    int padding[1];     // Aligns to power-of-two boundary, increases performance significantly.
};


// Vertex type; same format is used for all shapes for simplicity.
// Shapes are built by adding vertices to Model.
struct Vertex
{
    Vector3f  Pos;
    Color     C;
    float     U, V;	
    Vector3f  Norm;

    Vertex (const Vector3f& p, const Color& c = Color(64,0,0,255), 
        float u = 0, float v = 0, Vector3f n = Vector3f(1,0,0))
        : Pos(p), C(c), U(u), V(v), Norm(n)
    {}
    Vertex(float x, float y, float z, const Color& c = Color(64,0,0,255),
        float u = 0, float v = 0) : Pos(x,y,z), C(c), U(u), V(v)
    { }

    bool operator==(const Vertex& b) const
    {
        return Pos == b.Pos && C == b.C && U == b.U && V == b.V;
    }
};


//----------------------------------------------------------------------------
// ***** D3D1X::DistortionRenderer

DistortionRenderer::DistortionRenderer(ovrHmd hmd, FrameTimeManager& timeManager,
                                       const HMDRenderState& renderState)
    : CAPI::DistortionRenderer(ovrRenderAPI_D3D11, hmd, timeManager, renderState)
{
    SrgbBackBuffer = false;

    EyeTextureSize[0]    = Sizei(0);
    EyeRenderViewport[0] = Recti();
    EyeTextureSize[1]    = Sizei(0);
    EyeRenderViewport[1] = Recti();
}

DistortionRenderer::~DistortionRenderer()
{
    destroy();
}

// static
CAPI::DistortionRenderer* DistortionRenderer::Create(ovrHmd hmd,
                                                     FrameTimeManager& timeManager,
                                                     const HMDRenderState& renderState)
{
    return new DistortionRenderer(hmd, timeManager, renderState);
}


bool DistortionRenderer::Initialize(const ovrRenderAPIConfig* apiConfig)
{
    const ovrD3D1X(Config)* config = (const ovrD3D1X(Config)*)apiConfig;

    if (!config)
    {
        // Cleanup
        pEyeTextures[0].Clear();
        pEyeTextures[1].Clear();
        memset(&RParams, 0, sizeof(RParams));
        return true;
    }

    if (!config->D3D_NS.pDevice || !config->D3D_NS.pBackBufferRT)
        return false;

    if (System::DirectDisplayEnabled())
    {
        Ptr<IUnknown> ovrSwapChain;
        if (config->D3D_NS.pSwapChain->QueryInterface(IID_OVRDXGISwapchain, (void**)&ovrSwapChain.GetRawRef()) == E_NOINTERFACE)
        {
            OVR_DEBUG_LOG_TEXT(("ovr_Initialize() or ovr_InitializeRenderingShim() wasn't called before DXGISwapChain was created."));
        }
    }

    RParams.pDevice		   = config->D3D_NS.pDevice;    
    RParams.pContext       = D3DSELECT_10_11(config->D3D_NS.pDevice, config->D3D_NS.pDeviceContext);
    RParams.pBackBufferRT  = config->D3D_NS.pBackBufferRT;
#if (OVR_D3D_VERSION>=11)
    RParams.pBackBufferUAV = config->D3D_NS.pBackBufferUAV;
#else
    RParams.pBackBufferUAV = NULL;
#endif
    RParams.pSwapChain     = config->D3D_NS.pSwapChain;
    RParams.BackBufferSize = config->D3D_NS.Header.BackBufferSize;
    RParams.Multisample    = config->D3D_NS.Header.Multisample;

	GfxState = *new GraphicsState(RParams.pContext);

    D3D1X_(RENDER_TARGET_VIEW_DESC) backBufferDesc;
    RParams.pBackBufferRT->GetDesc(&backBufferDesc);
    SrgbBackBuffer = (backBufferDesc.Format == DXGI_FORMAT_R8G8B8A8_UNORM_SRGB) || 
                     (backBufferDesc.Format == DXGI_FORMAT_B8G8R8A8_UNORM_SRGB) || 
                     (backBufferDesc.Format == DXGI_FORMAT_B8G8R8X8_UNORM_SRGB);


#if 0   // enable related section in DistortionChroma.psh shader
    // aniso requires proper sRGB sampling
    SampleMode hqFilter = (RState.DistortionCaps & ovrDistortionCap_HqDistortion) ? Sample_Anisotropic : Sample_Linear;
#else
    SampleMode hqFilter = Sample_Linear;
#endif

    pEyeTextures[0] = *new Texture(&RParams, Texture_RGBA, Sizei(0),
                                   getSamplerState(hqFilter|Sample_ClampBorder));
    pEyeTextures[1] = *new Texture(&RParams, Texture_RGBA, Sizei(0),
                                   getSamplerState(hqFilter|Sample_ClampBorder));

    initBuffersAndShaders();

    // Rasterizer state
    D3D1X_(RASTERIZER_DESC) rs;
    memset(&rs, 0, sizeof(rs));
    rs.AntialiasedLineEnable = true;
    rs.CullMode              = D3D1X_(CULL_BACK);    
    rs.DepthClipEnable       = true;
    rs.FillMode              = D3D1X_(FILL_SOLID);
    Rasterizer = NULL;
    RParams.pDevice->CreateRasterizerState(&rs, &Rasterizer.GetRawRef());

	initOverdrive();

    // TBD: Blend state.. not used?
    // We'll want to turn off blending

#if (OVR_D3D_VERSION == 11)
    GpuProfiler.Init(RParams.pDevice, RParams.pContext);
#endif

    return true;
}

void DistortionRenderer::initOverdrive()
{
	if(RState.DistortionCaps & ovrDistortionCap_Overdrive)
	{
		LastUsedOverdriveTextureIndex = 0;

        D3D1X_(RENDER_TARGET_VIEW_DESC) backBufferDesc;
        RParams.pBackBufferRT->GetDesc(&backBufferDesc);
        
		for (int i = 0; i < NumOverdriveTextures; i++)
		{
			pOverdriveTextures[i] = *new Texture(&RParams, Texture_RGBA, RParams.BackBufferSize,
                getSamplerState(Sample_Linear|Sample_ClampBorder));

			D3D1X_(TEXTURE2D_DESC) dsDesc;
			dsDesc.Width     = RParams.BackBufferSize.w;
			dsDesc.Height    = RParams.BackBufferSize.h;
			dsDesc.MipLevels = 1;
			dsDesc.ArraySize = 1;
			dsDesc.Format    = backBufferDesc.Format;
			dsDesc.SampleDesc.Count = 1;
			dsDesc.SampleDesc.Quality = 0;
			dsDesc.Usage     = D3D1X_(USAGE_DEFAULT);
			dsDesc.BindFlags = D3D1X_(BIND_SHADER_RESOURCE) | D3D1X_(BIND_RENDER_TARGET);
			dsDesc.CPUAccessFlags = 0;
			dsDesc.MiscFlags      = 0;

			HRESULT hr = RParams.pDevice->CreateTexture2D(&dsDesc, NULL, &pOverdriveTextures[i]->Tex.GetRawRef());			
			if (FAILED(hr))
			{
				OVR_DEBUG_LOG_TEXT(("Failed to create overdrive texture."));
				// Remove overdrive flag since we failed to create the texture
				LastUsedOverdriveTextureIndex = -1;	// disables feature
				break;
			}

			RParams.pDevice->CreateShaderResourceView(pOverdriveTextures[i]->Tex, NULL, &pOverdriveTextures[i]->TexSv.GetRawRef());
			RParams.pDevice->CreateRenderTargetView(pOverdriveTextures[i]->Tex, NULL, &pOverdriveTextures[i]->TexRtv.GetRawRef());
		}
	}
	else
	{
		LastUsedOverdriveTextureIndex = -1;
	}
}

void DistortionRenderer::SubmitEye(int eyeId, const ovrTexture* eyeTexture)
{
    const ovrD3D1X(Texture)* tex = (const ovrD3D1X(Texture)*)eyeTexture;

    if (eyeTexture)
    {
        // Use tex->D3D_NS.Header.RenderViewport to update UVs for rendering in case they changed.
        // TBD: This may be optimized through some caching. 
        EyeTextureSize[eyeId]    = tex->D3D_NS.Header.TextureSize;
        EyeRenderViewport[eyeId] = tex->D3D_NS.Header.RenderViewport;

        const ovrEyeRenderDesc& erd = RState.EyeRenderDesc[eyeId];

        ovrHmd_GetRenderScaleAndOffset(erd.Fov,
                                       EyeTextureSize[eyeId], EyeRenderViewport[eyeId],
                                       UVScaleOffset[eyeId]);

		if (RState.DistortionCaps & ovrDistortionCap_FlipInput)
		{
			UVScaleOffset[eyeId][0].y = -UVScaleOffset[eyeId][0].y;
			UVScaleOffset[eyeId][1].y = 1.0f - UVScaleOffset[eyeId][1].y;
		}

        pEyeTextures[eyeId]->UpdatePlaceholderTexture(tex->D3D_NS.pTexture, tex->D3D_NS.pSRView,
                                                      tex->D3D_NS.Header.TextureSize);
    }
}

void DistortionRenderer::renderEndFrame()
{
    renderDistortion(pEyeTextures[0], pEyeTextures[1]);
    
    if(RegisteredPostDistortionCallback)
        RegisteredPostDistortionCallback(RParams.pContext);

    if(LatencyTest2Active)
    {
        renderLatencyPixel(LatencyTest2DrawColor);
    }
}

void DistortionRenderer::EndFrame(bool swapBuffers)
{
    // Don't spin if we are explicitly asked not to
    if ((RState.DistortionCaps & ovrDistortionCap_TimeWarp) &&
        !(RState.DistortionCaps & ovrDistortionCap_ProfileNoTimewarpSpinWaits))
    {
        if (!TimeManager.NeedDistortionTimeMeasurement())
        {
            // Wait for timewarp distortion if it is time and Gpu idle
            FlushGpuAndWaitTillTime(TimeManager.GetFrameTiming().TimewarpPointTime);

            renderEndFrame();
        }
        else
        {
            // If needed, measure distortion time so that TimeManager can better estimate
            // latency-reducing time-warp wait timing.
            WaitUntilGpuIdle();
            double  distortionStartTime = ovr_GetTimeInSeconds();

            renderEndFrame();

            WaitUntilGpuIdle();
            TimeManager.AddDistortionTimeMeasurement(ovr_GetTimeInSeconds() - distortionStartTime);
        }
    }
    else
    {
        renderEndFrame();
    }

    if(LatencyTestActive)
    {
        renderLatencyQuad(LatencyTestDrawColor);
    }

    if (swapBuffers)
    {
        if (RParams.pSwapChain)
        {
            UINT swapInterval = (RState.EnabledHmdCaps & ovrHmdCap_NoVSync) ? 0 : 1;
            RParams.pSwapChain->Present(swapInterval, 0);
            
            // Force GPU to flush the scene, resulting in the lowest possible latency.
            // It's critical that this flush is *after* present.
			// With the display driver this flush is obsolete and theoretically should
			// be a no-op.
            // Doesn't need to be done if running through the Oculus driver.
            if (RState.OurHMDInfo.InCompatibilityMode &&
                !(RState.DistortionCaps & ovrDistortionCap_ProfileNoTimewarpSpinWaits))
                WaitUntilGpuIdle();
        }
        else
        {
            // TBD: Generate error - swapbuffer option used with null swapchain.
        }
    }
}


void DistortionRenderer::WaitUntilGpuIdle()
{
    // Flush and Stall CPU while waiting for GPU to complete rendering all of the queued draw calls
    D3D1x_QUERY_DESC queryDesc = { D3D1X_(QUERY_EVENT), 0 };
    Ptr<ID3D1xQuery> query;
    BOOL             done = FALSE;

    if (RParams.pDevice->CreateQuery(&queryDesc, &query.GetRawRef()) == S_OK)
    {
        D3DSELECT_10_11(query->End(),
                        RParams.pContext->End(query));

        // GetData will returns S_OK for both done == TRUE or FALSE.
        // Exit on failure to avoid infinite loop.
        do { }
        while(!done &&
              !FAILED(D3DSELECT_10_11(query->GetData(&done, sizeof(BOOL), 0),
                                      RParams.pContext->GetData(query, &done, sizeof(BOOL), 0)))
             );
    }
}

double DistortionRenderer::FlushGpuAndWaitTillTime(double absTime)
{
    RParams.pContext->Flush();
    return WaitTillTime(absTime);
}

void DistortionRenderer::initBuffersAndShaders()
{
    if ( RState.DistortionCaps & ovrDistortionCap_ComputeShader )
    {
        // Compute shader distortion grid.
        // TODO - only do this if the CS is actually enabled?
	    for ( int eyeNum = 0; eyeNum < 2; eyeNum++ )
	    {
            // Compute shader setup of regular grid.
            DistortionMeshVBs[eyeNum] = NULL;
            DistortionMeshIBs[eyeNum] = NULL;

            // These constants need to match those declared in the shader in DistortionCS*.csh
            const int gridSizeInPixels = 16;
            const int pinsPerEdge = 128;


            // TODO: clean up this mess!
            HMDState* hmds = (HMDState*)HMD->Handle;
            ovrEyeType eyeType = RState.EyeRenderDesc[eyeNum].Eye;
            ovrFovPort fov = RState.EyeRenderDesc[eyeNum].Fov;

            const HmdRenderInfo&  hmdri          = hmds->RenderState.RenderInfo;    
            DistortionRenderDesc& distortion = hmds->RenderState.Distortion[eyeType];


            // Find the mapping from TanAngle space to target NDC space.
            ScaleAndOffset2D      eyeToSourceNDC = CreateNDCScaleAndOffsetFromFov(fov);

		    //const StereoEyeParams &stereoParams = ( eyeNum == 0 ) ? stereoParamsLeft : stereoParamsRight;
            OVR_ASSERT ( gridSizeInPixels * (pinsPerEdge-1) > hmdri.ResolutionInPixels.w/2 );
            OVR_ASSERT ( gridSizeInPixels * (pinsPerEdge-1) > hmdri.ResolutionInPixels.h );
            DistortionComputePin Verts[pinsPerEdge*pinsPerEdge];
            // Vertices are laid out in a vertical scanline pattern,
            // scanning right to left, then within each scan going top to bottom, like DK2.
            // If we move to a different panel orientation, we may need to flip this around.
            int vertexNum = 0;
            for ( int x = 0; x < pinsPerEdge; x++ )
            {
                for ( int y = 0; y < pinsPerEdge; y++ )
                {
                    int pixX = x * gridSizeInPixels;
                    int pixY = y * gridSizeInPixels;
    #if 0
                    // Simple version, ignoring pentile offsets
                    Vector2f screenPosNdc;
                    screenPosNdc.x = 2.0f * (  0.5f - ( (float)pixX / (hmdri.ResolutionInPixels.w/2) ) );      // Note signs!
                    screenPosNdc.y = 2.0f * ( -0.5f + ( (float)pixY / hmdri.ResolutionInPixels.h ) );      // Note signs!

                    DistortionMeshVertexData vertex = DistortionMeshMakeVertex ( screenPosNdc,
                                                                                    ( eyeNum == 1 ),
                                                                                    hmdri,
                                                                                    distortion,
                                                                                    eyeToSourceNDC );
                    DistortionComputePin *pCurVert = &(Verts[vertexNum]);
                    pCurVert->TanEyeAnglesR = vertex.TanEyeAnglesR;
                    pCurVert->TanEyeAnglesG = vertex.TanEyeAnglesG;
                    pCurVert->TanEyeAnglesB = vertex.TanEyeAnglesB;
    #else
                    // Pentile offsets are messy.
                    Vector2f screenPos[3];      // R=0, G=1, B=2
                    DistortionMeshVertexData vertexRGB[3];
                    screenPos[1] = Vector2f ( (float)pixX, (float)pixY );
                    screenPos[0] = screenPos[1];
                    screenPos[2] = screenPos[1];

                    if ( ( hmds->RenderState.EnabledHmdCaps & ovrHmdCap_DirectPentile ) != 0 )
                    {
                        // Doing direct display, so enable the pentile offsets.
                        screenPos[0] = screenPos[1] + hmdri.PelOffsetR;
                        screenPos[2] = screenPos[1] + hmdri.PelOffsetB;
                    }

                    for ( int i = 0; i < 3; i++ )
                    {
                        Vector2f screenPosNdc;
                        screenPosNdc.x = 2.0f * (  0.5f - ( screenPos[i].x / (hmdri.ResolutionInPixels.w/2) ) );      // Note signs!
                        screenPosNdc.y = 2.0f * ( -0.5f + ( screenPos[i].y / hmdri.ResolutionInPixels.h ) );      // Note signs!
                        vertexRGB[i] = DistortionMeshMakeVertex ( screenPosNdc,
                                                                    ( eyeNum == 1 ),
                                                                    hmdri,
                                                                    distortion,
                                                                    eyeToSourceNDC );
                    }
                    // Most data (fade, TW interpolate, etc) comes from the green channel.
                    DistortionMeshVertexData vertex = vertexRGB[1];
                    DistortionComputePin *pCurVert = &(Verts[vertexNum]);
                    pCurVert->TanEyeAnglesR = vertexRGB[0].TanEyeAnglesR;
                    pCurVert->TanEyeAnglesG = vertexRGB[1].TanEyeAnglesG;
                    pCurVert->TanEyeAnglesB = vertexRGB[2].TanEyeAnglesB;
    #endif

				    // vertex.Shade will go negative beyond the edges to produce correct intercept with the 0.0 plane.
				    // We want to preserve this, so bias and offset to fit [-1,+1] in a byte.
				    // The reverse wll be done in the shader.
				    float shade = Alg::Clamp ( vertex.Shade * 0.5f + 0.5f, 0.0f, 1.0f );
				    pCurVert->Col.R = (OVR::UByte)( floorf ( shade * 255.999f ) );
				    pCurVert->Col.G = pCurVert->Col.R;
				    pCurVert->Col.B = pCurVert->Col.R;
				    pCurVert->Col.A = (OVR::UByte)( floorf ( vertex.TimewarpLerp * 255.999f ) );

                    vertexNum++;
                }
            }
            DistortionPinBuffer[eyeNum] = *new Buffer(&RParams);
            DistortionPinBuffer[eyeNum]->Data ( Buffer_Compute, Verts, vertexNum * sizeof(Verts[0]), sizeof(Verts[0]) );
        }

    }
    else
    {
        for ( int eyeNum = 0; eyeNum < 2; eyeNum++ )
        {
            // Allocate & generate distortion mesh vertices.
            DistortionPinBuffer[eyeNum] = NULL;

            ovrDistortionMesh meshData;

    //        double startT = ovr_GetTimeInSeconds();

            if (!ovrHmd_CreateDistortionMesh( HMD,
                                              RState.EyeRenderDesc[eyeNum].Eye,
                                              RState.EyeRenderDesc[eyeNum].Fov,
                                              RState.DistortionCaps,
                                              &meshData) )
            {
                OVR_ASSERT(false);
                continue;
            }

    //        double deltaT = ovr_GetTimeInSeconds() - startT;
    //        LogText("GenerateDistortion time = %f\n", deltaT);

            // Now parse the vertex data and create a render ready vertex buffer from it
            DistortionVertex *   pVBVerts    = (DistortionVertex*)OVR_ALLOC ( sizeof(DistortionVertex) * meshData.VertexCount );
            DistortionVertex *   pCurVBVert  = pVBVerts;
            ovrDistortionVertex* pCurOvrVert = meshData.pVertexData;

            for ( unsigned vertNum = 0; vertNum < meshData.VertexCount; vertNum++ )
            {
                pCurVBVert->ScreenPosNDC.x = pCurOvrVert->ScreenPosNDC.x;
                pCurVBVert->ScreenPosNDC.y = pCurOvrVert->ScreenPosNDC.y;
                pCurVBVert->TanEyeAnglesR  = (*(Vector2f*)&pCurOvrVert->TanEyeAnglesR);
                pCurVBVert->TanEyeAnglesG  = (*(Vector2f*)&pCurOvrVert->TanEyeAnglesG);
                pCurVBVert->TanEyeAnglesB  = (*(Vector2f*)&pCurOvrVert->TanEyeAnglesB);

                // Convert [0.0f,1.0f] to [0,255]
			    if (RState.DistortionCaps & ovrDistortionCap_Vignette)
				    pCurVBVert->Col.R = (uint8_t)( Alg::Max ( pCurOvrVert->VignetteFactor, 0.0f ) * 255.99f );
			    else
				    pCurVBVert->Col.R = 255;

                pCurVBVert->Col.G = pCurVBVert->Col.R;
                pCurVBVert->Col.B = pCurVBVert->Col.R;
                pCurVBVert->Col.A = (uint8_t)( pCurOvrVert->TimeWarpFactor * 255.99f );
                pCurOvrVert++;
                pCurVBVert++;
            }

            DistortionMeshVBs[eyeNum] = *new Buffer(&RParams);
		    DistortionMeshVBs[eyeNum]->Data(Buffer_Vertex | Buffer_ReadOnly, pVBVerts, sizeof(DistortionVertex)* meshData.VertexCount);
            DistortionMeshIBs[eyeNum] = *new Buffer(&RParams);
		    DistortionMeshIBs[eyeNum]->Data(Buffer_Index | Buffer_ReadOnly, meshData.pIndexData, (sizeof(INT16)* meshData.IndexCount));

            OVR_FREE ( pVBVerts );
            ovrHmd_DestroyDistortionMesh( &meshData );
        }
    }


    // Uniform buffers
    for(int i = 0; i < Shader_Count; i++)
    {
        UniformBuffers[i] = *new Buffer(&RParams);
        //MaxTextureSet[i] = 0;
    }

    initShaders();
}

void DistortionRenderer::renderDistortion(Texture* leftEyeTexture, Texture* rightEyeTexture)
{

#if (OVR_D3D_VERSION == 10)
	RParams.pContext->GSSetShader(NULL);
#else // d3d 11
	RParams.pContext->HSSetShader(NULL, NULL, 0);
	RParams.pContext->DSSetShader(NULL, NULL, 0);
	RParams.pContext->GSSetShader(NULL, NULL, 0);
#endif

    RParams.pContext->RSSetState(Rasterizer);

	bool overdriveActive = IsOverdriveActive();
	int currOverdriveTextureIndex = -1;

	if(overdriveActive)
	{
		currOverdriveTextureIndex = (LastUsedOverdriveTextureIndex + 1) % NumOverdriveTextures;
        ID3D1xRenderTargetView* distortionRtv = pOverdriveTextures[currOverdriveTextureIndex]->TexRtv.GetRawRef();
        ID3D1xRenderTargetView* mrtRtv[2] = {distortionRtv, RParams.pBackBufferRT};
        RParams.pContext->OMSetRenderTargets(2, mrtRtv, 0);

        RParams.pContext->ClearRenderTargetView(distortionRtv, RState.ClearColor);
    }
    else
    {
        RParams.pContext->OMSetRenderTargets(1, &RParams.pBackBufferRT, 0);
    }

    // Not affected by viewport.
    RParams.pContext->ClearRenderTargetView(RParams.pBackBufferRT, RState.ClearColor);

    setViewport(Recti(0,0, RParams.BackBufferSize.w, RParams.BackBufferSize.h));


    for(int eyeNum = 0; eyeNum < 2; eyeNum++)
    {
		ShaderFill distortionShaderFill(DistortionShader);
        distortionShaderFill.SetTexture(0, eyeNum == 0 ? leftEyeTexture : rightEyeTexture, Shader_Pixel);

        if(RState.DistortionCaps & ovrDistortionCap_HqDistortion)
        {
            static float aaDerivMult = 1.0f;
            DistortionShader->SetUniform1f("AaDerivativeMult", aaDerivMult);
        }
        else
        {
            // 0.0 disables high quality anti-aliasing
            DistortionShader->SetUniform1f("AaDerivativeMult", -1.0f);
        }

		if(overdriveActive)
		{
            distortionShaderFill.SetTexture(1, pOverdriveTextures[LastUsedOverdriveTextureIndex], Shader_Pixel);
            
            float overdriveScaleRegularRise;
            float overdriveScaleRegularFall;
            GetOverdriveScales(overdriveScaleRegularRise, overdriveScaleRegularFall);
			DistortionShader->SetUniform2f("OverdriveScales", overdriveScaleRegularRise, overdriveScaleRegularFall);
		}
        else
        {
            // -1.0f disables PLO            
            DistortionShader->SetUniform2f("OverdriveScales", -1.0f, -1.0f);
        }

        distortionShaderFill.SetInputLayout(DistortionVertexIL);

        DistortionShader->SetUniform2f("EyeToSourceUVScale",  UVScaleOffset[eyeNum][0].x, UVScaleOffset[eyeNum][0].y);
        DistortionShader->SetUniform2f("EyeToSourceUVOffset", UVScaleOffset[eyeNum][1].x, UVScaleOffset[eyeNum][1].y);
        

		if (RState.DistortionCaps & ovrDistortionCap_TimeWarp)
		{                       
            ovrMatrix4f timeWarpMatrices[2];
            ovrHmd_GetEyeTimewarpMatrices(HMD, (ovrEyeType)eyeNum,
                                          RState.EyeRenderPoses[eyeNum], timeWarpMatrices);

    		if (RState.DistortionCaps & ovrDistortionCap_ComputeShader)
            {
			    DistortionShader->SetUniform3x3f("EyeRotationStart", Matrix4f(timeWarpMatrices[0]));
			    DistortionShader->SetUniform3x3f("EyeRotationEnd",   Matrix4f(timeWarpMatrices[1]));
            }
            else
            {
                // Can feed identity like matrices incase of concern over timewarp calculations
			    DistortionShader->SetUniform4x4f("EyeRotationStart", Matrix4f(timeWarpMatrices[0]));
			    DistortionShader->SetUniform4x4f("EyeRotationEnd",   Matrix4f(timeWarpMatrices[1]));
            }
		}


		if (RState.DistortionCaps & ovrDistortionCap_ComputeShader)
        {
#if (OVR_D3D_VERSION >= 11)
            //RParams.pContext->CSCSSetShaderResources
            //RParams.pContext->CSSetUnorderedAccessViews
            //RParams.pContext->CSSetShader
            //RParams.pContext->CSSetSamplers
            //RParams.pContext->CSSetConstantBuffers


			// These need to match the values used in the compiled shader
            //const int gridSizeInPixels = 16;        // GRID_SIZE_IN_PIXELS
            //const int pinsPerEdge = 128;            // PINS_PER_EDGE
			const int nxnBlockSizeInPixels = 2;		// NXN_BLOCK_SIZE_PIXELS
			const int simdSquareSize = 16;			// SIMD_SQUARE_SIZE

			const int invocationSizeInPixels = nxnBlockSizeInPixels * simdSquareSize;

            distortionShaderFill.SetTexture(0, eyeNum == 0 ? leftEyeTexture : rightEyeTexture, Shader_Compute);

            DistortionShader->SetUniform1f("RightEye", (float)eyeNum);
            DistortionShader->SetUniform1f("UseOverlay", 0.0f);             // No overlay supported here.
            DistortionShader->SetUniform1f("FbSizePixelsX", (float)RParams.BackBufferSize.w);

            ShaderSet* shaders = distortionShaderFill.GetShaders();
            ShaderBase* cshader = ((ShaderBase*)shaders->GetShader(Shader_Compute));

            ID3D1xUnorderedAccessView *uavRendertarget = RParams.pBackBufferUAV;
            int SizeX = RParams.BackBufferSize.w/2;
            int SizeY = RParams.BackBufferSize.h;

            int TileNumX = ( SizeX + (invocationSizeInPixels-1) ) / invocationSizeInPixels;
            int TileNumY = ( SizeY + (invocationSizeInPixels-1) ) / invocationSizeInPixels;

            RParams.pContext->CSSetUnorderedAccessViews ( 0, 1, &uavRendertarget, NULL );


            // Incoming eye-buffer textures start at t0 onwards, so set this in slot #4
            // Subtlety - can't put this in slot 0 because fill->Set stops at the first NULL texture.
            ID3D1xShaderResourceView *d3dSrv = DistortionPinBuffer[eyeNum]->GetSrv();
            RParams.pContext->CSSetShaderResources ( 4, 1, &d3dSrv );

            // TODO: uniform/constant buffers
            cshader->UpdateBuffer(UniformBuffers[Shader_Compute]);
            cshader->SetUniformBuffer(UniformBuffers[Shader_Compute]);

            // Primitive type is ignored for CS.
            // This call actually sets the textures and does pContext->CSSetShader(). Primitive type is ignored.
            distortionShaderFill.Set ( Prim_Unknown );

            RParams.pContext->Dispatch ( TileNumX, TileNumY, 1 );
#else
            OVR_ASSERT ( !"No compute shaders on DX10" );
#endif
        }
        else
        {
            renderPrimitives(&distortionShaderFill, DistortionMeshVBs[eyeNum], DistortionMeshIBs[eyeNum],
                            NULL, 0, (int)DistortionMeshIBs[eyeNum]->GetSize()/2, Prim_Triangles);
        }
    }

    LastUsedOverdriveTextureIndex = currOverdriveTextureIndex;

    // Re-activate to only draw on back buffer
    if(overdriveActive)
    {
        RParams.pContext->OMSetRenderTargets(1, &RParams.pBackBufferRT, 0);
    }
}

void DistortionRenderer::createDrawQuad()
{
    const int numQuadVerts = 4;
    LatencyTesterQuadVB = *new Buffer(&RParams);
    if(!LatencyTesterQuadVB)
    {
        return;
    }

    LatencyTesterQuadVB->Data(Buffer_Vertex, NULL, numQuadVerts * sizeof(Vertex));
    Vertex* vertices = (Vertex*)LatencyTesterQuadVB->Map(0, numQuadVerts * sizeof(Vertex), Map_Discard);
    if(!vertices)
    {
        OVR_ASSERT(false); // failed to lock vertex buffer
        return;
    }

    const float left   = -1.0f;
    const float top    = -1.0f;
    const float right  =  1.0f;
    const float bottom =  1.0f;

    vertices[0] = Vertex(Vector3f(left,  top,    0.0f), Color(255, 255, 255, 255));
    vertices[1] = Vertex(Vector3f(left,  bottom, 0.0f), Color(255, 255, 255, 255));
    vertices[2] = Vertex(Vector3f(right, top,    0.0f), Color(255, 255, 255, 255));
    vertices[3] = Vertex(Vector3f(right, bottom, 0.0f), Color(255, 255, 255, 255));

    LatencyTesterQuadVB->Unmap(vertices);
}

void DistortionRenderer::renderLatencyQuad(unsigned char* latencyTesterDrawColor)
{
    const int numQuadVerts = 4;

    if(!LatencyTesterQuadVB)
    {
        createDrawQuad();
    }
       
    ShaderFill quadFill(SimpleQuadShader);
    quadFill.SetInputLayout(SimpleQuadVertexIL);

    setViewport(Recti(0,0, RParams.BackBufferSize.w, RParams.BackBufferSize.h));

    float testerLuminance = (float)latencyTesterDrawColor[0] / 255.99f;
    if(SrgbBackBuffer)
    {
        testerLuminance = pow(testerLuminance, 2.2f);
    }

    SimpleQuadShader->SetUniform2f("Scale", 0.3f, 0.3f);
    SimpleQuadShader->SetUniform4f("Color", testerLuminance, testerLuminance, testerLuminance, 1.0f);

    for(int eyeNum = 0; eyeNum < 2; eyeNum++)
    {
        SimpleQuadShader->SetUniform2f("PositionOffset", eyeNum == 0 ? -0.5f : 0.5f, 0.0f);    
        renderPrimitives(&quadFill, LatencyTesterQuadVB, NULL, NULL, 0, numQuadVerts, Prim_TriangleStrip);
    }
}

void DistortionRenderer::renderLatencyPixel(unsigned char* latencyTesterPixelColor)
{
    const int numQuadVerts = 4;

    if(!LatencyTesterQuadVB)
    {
        createDrawQuad();
    }
    
    ShaderFill quadFill(SimpleQuadShader);
    quadFill.SetInputLayout(SimpleQuadVertexIL);

    setViewport(Recti(0,0, RParams.BackBufferSize.w, RParams.BackBufferSize.h));

    Vector3f testerColor = Vector3f((float)latencyTesterPixelColor[0] / 255.99f, 
                                    (float)latencyTesterPixelColor[1] / 255.99f,
                                    (float)latencyTesterPixelColor[2] / 255.99f);
    if(SrgbBackBuffer)
    {
        // 2.2 gamma is close enough for our purposes of matching sRGB
        testerColor.x = pow(testerColor.x, 2.2f);
        testerColor.y = pow(testerColor.y, 2.2f);
        testerColor.z = pow(testerColor.z, 2.2f);
    }

#ifdef OVR_BUILD_DEBUG
    SimpleQuadShader->SetUniform4f("Color", testerColor.x, testerColor.y, testerColor.z, 1.0f);

    Vector2f scale(20.0f / RParams.BackBufferSize.w, 20.0f / RParams.BackBufferSize.h); 
#else
    // sending in as gray scale
    SimpleQuadShader->SetUniform4f("Color", testerColor.x, testerColor.x, testerColor.x, 1.0f);

    Vector2f scale(1.0f / RParams.BackBufferSize.w, 1.0f / RParams.BackBufferSize.h); 
#endif
    SimpleQuadShader->SetUniform2f("Scale", scale.x, scale.y);
    SimpleQuadShader->SetUniform2f("PositionOffset", 1.0f-scale.x, 1.0f-scale.y);
    renderPrimitives(&quadFill, LatencyTesterQuadVB, NULL, NULL, 0, numQuadVerts, Prim_TriangleStrip);
}

void DistortionRenderer::renderPrimitives(
                          const ShaderFill* fill,
                          Buffer* vertices, Buffer* indices,
                          Matrix4f* viewMatrix, int offset, int count,
                          PrimitiveType rprim)
{
    OVR_ASSERT(fill->GetInputLayout() != 0);    
    RParams.pContext->IASetInputLayout((ID3D1xInputLayout*)fill->GetInputLayout());    

    if (indices)
    {
        RParams.pContext->IASetIndexBuffer(indices->GetBuffer(), DXGI_FORMAT_R16_UINT, 0);
    }

    ID3D1xBuffer* vertexBuffer = vertices->GetBuffer();
    UINT          vertexStride = sizeof(Vertex);
    UINT          vertexOffset = offset;
    RParams.pContext->IASetVertexBuffers(0, 1, &vertexBuffer, &vertexStride, &vertexOffset);

    ShaderSet* shaders = ((ShaderFill*)fill)->GetShaders();

    ShaderBase*     vshader = ((ShaderBase*)shaders->GetShader(Shader_Vertex));
    unsigned char*  vertexData = vshader->UniformData;
    if (vertexData)
    {
		// TODO: some VSes don't start with StandardUniformData!
		if ( viewMatrix )
		{
			StandardUniformData* stdUniforms = (StandardUniformData*) vertexData;
			stdUniforms->View = viewMatrix->Transposed();
			stdUniforms->Proj = StdUniforms.Proj;
		}
		UniformBuffers[Shader_Vertex]->Data(Buffer_Uniform, vertexData, vshader->UniformsSize);
		vshader->SetUniformBuffer(UniformBuffers[Shader_Vertex]);
    }

    for(int i = Shader_Vertex + 1; i < Shader_Count; i++)
    {
        if (shaders->GetShader(i))
        {
            ((ShaderBase*)shaders->GetShader(i))->UpdateBuffer(UniformBuffers[i]);
            ((ShaderBase*)shaders->GetShader(i))->SetUniformBuffer(UniformBuffers[i]);
        }
    }

    D3D1X_(PRIMITIVE_TOPOLOGY) prim;
    switch(rprim)
    {
    case Prim_Triangles:
        prim = D3D1X_(PRIMITIVE_TOPOLOGY_TRIANGLELIST);
        break;
    case Prim_Lines:
        prim = D3D1X_(PRIMITIVE_TOPOLOGY_LINELIST);
        break;
    case Prim_TriangleStrip:
        prim = D3D1X_(PRIMITIVE_TOPOLOGY_TRIANGLESTRIP);
        break;
    default:
        OVR_ASSERT(0);
        return;
    }
    RParams.pContext->IASetPrimitiveTopology(prim);

    fill->Set(rprim);

    if (indices)
    {
        RParams.pContext->DrawIndexed(count, 0, 0);
    }
    else
    {
        RParams.pContext->Draw(count, 0);
    }
}

void DistortionRenderer::setViewport(const Recti& vp)
{
    D3D1x_VIEWPORT d3dvp;

    d3dvp.Width    = D3DSELECT_10_11(vp.w, (float)vp.w);
    d3dvp.Height   = D3DSELECT_10_11(vp.h, (float)vp.h);
    d3dvp.TopLeftX = D3DSELECT_10_11(vp.x, (float)vp.x);
    d3dvp.TopLeftY = D3DSELECT_10_11(vp.y, (float)vp.y);
    d3dvp.MinDepth = 0;
    d3dvp.MaxDepth = 1;
    RParams.pContext->RSSetViewports(1, &d3dvp);
}



// Must match struct DistortionVertex
static D3D1X_(INPUT_ELEMENT_DESC) DistortionMeshVertexDesc[] =
{
    {"Position", 0, DXGI_FORMAT_R32G32_FLOAT,   0, 0,   D3D1X_(INPUT_PER_VERTEX_DATA), 0},
    {"TexCoord", 0, DXGI_FORMAT_R32G32_FLOAT,   0, 8,   D3D1X_(INPUT_PER_VERTEX_DATA), 0},
    {"TexCoord", 1, DXGI_FORMAT_R32G32_FLOAT,   0, 16,	D3D1X_(INPUT_PER_VERTEX_DATA), 0},
    {"TexCoord", 2, DXGI_FORMAT_R32G32_FLOAT,   0, 24,	D3D1X_(INPUT_PER_VERTEX_DATA), 0},
    {"Color",    0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, 32,  D3D1X_(INPUT_PER_VERTEX_DATA), 0},
};

static D3D1X_(INPUT_ELEMENT_DESC) SimpleQuadMeshVertexDesc[] =
{
    {"Position", 0, DXGI_FORMAT_R32G32_FLOAT,   0, 0,   D3D1X_(INPUT_PER_VERTEX_DATA), 0},
};



// TODO: this is D3D specific
void DistortionRenderer::initShaders()
{
#if OVR_D3D_VERSION>=11
    if ( ( RState.DistortionCaps & ovrDistortionCap_ComputeShader ) != 0 )
    {
        // Compute shader
        DistortionShader = *new ShaderSet;

        int shaderNum = DistortionComputeShader2x2;
        if ( ( RState.EnabledHmdCaps & ovrHmdCap_DirectPentile ) != 0 )
        {
            shaderNum = DistortionComputeShader2x2Pentile;
        }

        PrecompiledShader psShaderByteCode = DistortionComputeShaderLookup[shaderNum];
        Ptr<D3D_NS::ComputeShader> cs  = *new D3D_NS::ComputeShader(
            &RParams,
            (void*)psShaderByteCode.ShaderData, psShaderByteCode.ShaderSize,
            psShaderByteCode.ReflectionData, psShaderByteCode.ReflectionSize);

        DistortionShader->SetShader(cs);
    }
    else
#endif
    {
        // Vertex + pixel distortion shader.
        PrecompiledShader vsShaderByteCode = DistortionVertexShaderLookup[DistortionVertexShaderBitMask & RState.DistortionCaps];
        Ptr<D3D_NS::VertexShader> vtxShader = *new D3D_NS::VertexShader(
            &RParams,
            (void*)vsShaderByteCode.ShaderData, vsShaderByteCode.ShaderSize,
            vsShaderByteCode.ReflectionData, vsShaderByteCode.ReflectionSize);

        DistortionVertexIL = NULL;
        ID3D1xInputLayout** objRef = &DistortionVertexIL.GetRawRef();

        HRESULT validate = RParams.pDevice->CreateInputLayout(
            DistortionMeshVertexDesc, sizeof(DistortionMeshVertexDesc) / sizeof(DistortionMeshVertexDesc[0]),
            vsShaderByteCode.ShaderData, vsShaderByteCode.ShaderSize, objRef);
        OVR_UNUSED(validate);

        DistortionShader = *new ShaderSet;
        DistortionShader->SetShader(vtxShader);

        PrecompiledShader psShaderByteCode = DistortionPixelShaderLookup[DistortionPixelShaderBitMask & RState.DistortionCaps];

        Ptr<D3D_NS::PixelShader> ps  = *new D3D_NS::PixelShader(
            &RParams,
            (void*)psShaderByteCode.ShaderData, psShaderByteCode.ShaderSize,
            psShaderByteCode.ReflectionData, psShaderByteCode.ReflectionSize);

        DistortionShader->SetShader(ps);
    }

    {
        Ptr<D3D_NS::VertexShader> vtxShader = *new D3D_NS::VertexShader(
            &RParams,
            (void*)SimpleQuad_vs, sizeof(SimpleQuad_vs),
            SimpleQuad_vs_refl, sizeof(SimpleQuad_vs_refl) / sizeof(SimpleQuad_vs_refl[0]));
            //NULL, 0);

        SimpleQuadVertexIL = NULL;
        ID3D1xInputLayout** objRef   = &SimpleQuadVertexIL.GetRawRef();

        HRESULT validate = RParams.pDevice->CreateInputLayout(
            SimpleQuadMeshVertexDesc, sizeof(SimpleQuadMeshVertexDesc) / sizeof(SimpleQuadMeshVertexDesc[0]),
            (void*)SimpleQuad_vs, sizeof(SimpleQuad_vs), objRef);
        OVR_UNUSED(validate);

        SimpleQuadShader = *new ShaderSet;
        SimpleQuadShader->SetShader(vtxShader);

        Ptr<D3D_NS::PixelShader> ps  = *new D3D_NS::PixelShader(
            &RParams,
            (void*)SimpleQuad_ps, sizeof(SimpleQuad_ps),
            SimpleQuad_ps_refl, sizeof(SimpleQuad_ps_refl) / sizeof(SimpleQuad_ps_refl[0]));

        SimpleQuadShader->SetShader(ps);
    }
}



ID3D1xSamplerState* DistortionRenderer::getSamplerState(int sm)
{
    if (SamplerStates[sm])    
        return SamplerStates[sm];

    D3D1X_(SAMPLER_DESC) ss;
    memset(&ss, 0, sizeof(ss));
    if (sm & Sample_Clamp)    
        ss.AddressU = ss.AddressV = ss.AddressW = D3D1X_(TEXTURE_ADDRESS_CLAMP);    
    else if (sm & Sample_ClampBorder)    
        ss.AddressU = ss.AddressV = ss.AddressW = D3D1X_(TEXTURE_ADDRESS_BORDER);    
    else    
        ss.AddressU = ss.AddressV = ss.AddressW = D3D1X_(TEXTURE_ADDRESS_WRAP);

    if (sm & Sample_Nearest)
    {
        ss.Filter = D3D1X_(FILTER_MIN_MAG_MIP_POINT);
    }
    else if (sm & Sample_Anisotropic)
    {
        ss.Filter = D3D1X_(FILTER_ANISOTROPIC);
        ss.MaxAnisotropy = 4;
    }
    else
    {
        ss.Filter = D3D1X_(FILTER_MIN_MAG_MIP_LINEAR);
    }
    ss.MaxLOD = 15;
    RParams.pDevice->CreateSamplerState(&ss, &SamplerStates[sm].GetRawRef());
    return SamplerStates[sm];
}


void DistortionRenderer::destroy()
{
	for(int eyeNum = 0; eyeNum < 2; eyeNum++)
	{
		DistortionMeshVBs[eyeNum].Clear();
		DistortionMeshIBs[eyeNum].Clear();
        DistortionPinBuffer[eyeNum].Clear();
	}

	DistortionVertexIL.Clear();

	if (DistortionShader)
    {
        DistortionShader->UnsetShader(Shader_Vertex);
	    DistortionShader->UnsetShader(Shader_Pixel);
	    DistortionShader->UnsetShader(Shader_Compute);
	    DistortionShader.Clear();
    }

    LatencyTesterQuadVB.Clear();
}


DistortionRenderer::GraphicsState::GraphicsState(ID3D1xDeviceContext* c)
: context(c)
, memoryCleared(TRUE)
, rasterizerState(NULL)
//samplerStates[]
, inputLayoutState(NULL)
//psShaderResourceState[]
//vsShaderResourceState[]
//psConstantBuffersState[]
//vsConstantBuffersState[]
//renderTargetViewState[]
, depthStencilViewState(NULL)
, omBlendState(NULL)
//omBlendFactorState[]
, omSampleMaskState(0xffffffff)
, primitiveTopologyState(D3D_PRIMITIVE_TOPOLOGY_UNDEFINED) 
, iaIndexBufferPointerState(NULL)
, iaIndexBufferFormatState(DXGI_FORMAT_UNKNOWN)
, iaIndexBufferOffsetState(0)
//iaVertexBufferPointersState[]
//iaVertexBufferStridesState[]
//iaVertexBufferOffsetsState[]
, currentPixelShader(NULL)
, currentVertexShader(NULL)
, currentGeometryShader(NULL)
#if (OVR_D3D_VERSION == 11)
, currentHullShader(NULL)
, currentDomainShader(NULL)
, currentComputeShader(NULL)
#endif
{
	for (int i = 0; i < D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT; ++i)
    {
		psSamplerStates[i] = NULL;
		vsSamplerStates[i] = NULL;
#if (OVR_D3D_VERSION == 11)
		csSamplerStates[i] = NULL;
#endif
    }

	for (int i = 0; i < D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT; i++)
	{
		psShaderResourceState[i] = NULL;
		vsShaderResourceState[i] = NULL;
#if (OVR_D3D_VERSION == 11)
		csShaderResourceState[i] = NULL;
#endif
	}

	for (int i = 0; i < D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT; i++)
	{
		psConstantBuffersState[i] = NULL;
		vsConstantBuffersState[i] = NULL;
#if (OVR_D3D_VERSION == 11)
        csConstantBuffersState[i] = NULL;
#endif
    }

	for (int i = 0; i < D3D1x_SIMULTANEOUS_RENDER_TARGET_COUNT; i++)
    {
		renderTargetViewState[i] = NULL;
#if (OVR_D3D_VERSION == 11)
        csUnorderedAccessViewState[i] = NULL;
#endif
    }

	for (int i = 0; i < 4; i++)
		omBlendFactorState[i] = NULL;

	for (int i = 0; i < D3D1x_IA_VERTEX_INPUT_RESOURCE_SLOT_COUNT; i++)
	{
    	iaVertexBufferPointersState[i] = NULL;
        iaVertexBufferStridesState[i] = NULL;
        iaVertexBufferOffsetsState[i] = NULL;
    }
}

#define SAFE_RELEASE(x) if ( (x) != NULL ) { (x)->Release(); (x)=NULL; }

void DistortionRenderer::GraphicsState::clearMemory()
{
    SAFE_RELEASE ( rasterizerState );

	for (int i = 0; i < D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT; ++i)
	{
        SAFE_RELEASE ( psSamplerStates[i] );
        SAFE_RELEASE ( vsSamplerStates[i] );
#if (OVR_D3D_VERSION == 11)
        SAFE_RELEASE ( csSamplerStates[i] );
#endif
	}

    SAFE_RELEASE ( inputLayoutState );

	for (int i = 0; i < D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT; i++)
	{
        SAFE_RELEASE ( psShaderResourceState[i] );
        SAFE_RELEASE ( vsShaderResourceState[i] );
#if (OVR_D3D_VERSION == 11)
        SAFE_RELEASE ( csShaderResourceState[i] );
#endif
	}

	for (int i = 0; i < D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT; i++)
	{
        SAFE_RELEASE ( psConstantBuffersState[i] );
        SAFE_RELEASE ( vsConstantBuffersState[i] );
#if (OVR_D3D_VERSION == 11)
        SAFE_RELEASE ( csConstantBuffersState[i] );
#endif
	}

	for (int i = 0; i < D3D1x_SIMULTANEOUS_RENDER_TARGET_COUNT; i++)
	{
        SAFE_RELEASE ( renderTargetViewState[i] );
#if (OVR_D3D_VERSION == 11)
        SAFE_RELEASE ( csUnorderedAccessViewState[i] );
#endif
	}

    SAFE_RELEASE ( depthStencilViewState );
    SAFE_RELEASE ( omBlendState );
    SAFE_RELEASE ( iaIndexBufferPointerState );

	for (int i = 0; i < D3D1x_IA_VERTEX_INPUT_RESOURCE_SLOT_COUNT; i++)
	{
        SAFE_RELEASE ( iaVertexBufferPointersState[i] );
	}

    SAFE_RELEASE ( currentPixelShader );
    SAFE_RELEASE ( currentVertexShader );
    SAFE_RELEASE ( currentGeometryShader );

#if (OVR_D3D_VERSION == 11)
    SAFE_RELEASE ( currentHullShader );
    SAFE_RELEASE ( currentDomainShader );
    SAFE_RELEASE ( currentComputeShader );
#endif

	memoryCleared = TRUE;
}

#undef SAFE_RELEASE

DistortionRenderer::GraphicsState::~GraphicsState()
{
	clearMemory();
}


void DistortionRenderer::GraphicsState::Save()
{
	if (!memoryCleared)
		clearMemory();

	memoryCleared = FALSE;

	context->RSGetState(&rasterizerState);
	context->IAGetInputLayout(&inputLayoutState);

	context->PSGetShaderResources(0, D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT, psShaderResourceState);
	context->PSGetSamplers(0, D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT, psSamplerStates);
	context->PSGetConstantBuffers(0, D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT, psConstantBuffersState);

	context->VSGetShaderResources(0, D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT, vsShaderResourceState);
	context->VSGetSamplers(0, D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT, vsSamplerStates);
	context->VSGetConstantBuffers(0, D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT, vsConstantBuffersState);

#if (OVR_D3D_VERSION == 11)
	context->CSGetShaderResources(0, D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT, csShaderResourceState);
	context->CSGetSamplers(0, D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT, csSamplerStates);
	context->CSGetConstantBuffers(0, D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT, csConstantBuffersState);
	context->CSGetUnorderedAccessViews(0, D3D1x_SIMULTANEOUS_RENDER_TARGET_COUNT, csUnorderedAccessViewState);
#endif

	context->OMGetRenderTargets(D3D1x_SIMULTANEOUS_RENDER_TARGET_COUNT, renderTargetViewState, &depthStencilViewState);

	context->OMGetBlendState(&omBlendState, omBlendFactorState, &omSampleMaskState);

	context->IAGetPrimitiveTopology(&primitiveTopologyState);

	context->IAGetIndexBuffer(&iaIndexBufferPointerState, &iaIndexBufferFormatState, &iaIndexBufferOffsetState);

	context->IAGetVertexBuffers(0, D3D1x_IA_VERTEX_INPUT_RESOURCE_SLOT_COUNT, iaVertexBufferPointersState, iaVertexBufferStridesState, iaVertexBufferOffsetsState);

#if (OVR_D3D_VERSION == 10)
	context->PSGetShader(&currentPixelShader);
	context->VSGetShader(&currentVertexShader);
	context->GSGetShader(&currentGeometryShader);
#else // Volga says class instance interfaces are very new and almost no one uses them
	context->PSGetShader(&currentPixelShader, NULL, NULL);
	context->VSGetShader(&currentVertexShader, NULL, NULL);
	context->GSGetShader(&currentGeometryShader, NULL, NULL);
	context->HSGetShader(&currentHullShader, NULL, NULL);
	context->DSGetShader(&currentDomainShader, NULL, NULL);
	context->CSGetShader(&currentComputeShader, NULL, NULL);
	/* maybe above doesn't work; then do something with this (must test on dx11)
	ID3D11ClassInstance* blank_array[0];
	UINT blank_uint = 0;
	context->PSGetShader(&currentPixelShader, blank_array, blank_uint);
	context->VSGetShader(&currentVertexShader, blank_array, blank_uint);
	context->GSGetShader(&currentGeometryShader, blank_array, blank_uint);
	context->HSGetShader(&currentHullShader, blank_array, blank_uint);
	context->DSGetShader(&currentDomainShader, blank_array, blank_uint);
	context->CSGetShader(&currentComputeShader, blank_array, blank_uint);
	*/
#endif
}


void DistortionRenderer::GraphicsState::Restore()
{
	if (rasterizerState != NULL)
		context->RSSetState(rasterizerState);

	if (inputLayoutState != NULL)
		context->IASetInputLayout(inputLayoutState);

	context->PSSetSamplers(0, D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT, psSamplerStates);
	if (psShaderResourceState != NULL)
		context->PSSetShaderResources(0, D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT, psShaderResourceState);
	if (psConstantBuffersState != NULL)
		context->PSSetConstantBuffers(0, D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT, psConstantBuffersState);

	context->VSSetSamplers(0, D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT, vsSamplerStates);
	if (vsShaderResourceState != NULL)
		context->VSSetShaderResources(0, D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT, vsShaderResourceState);
	if (vsConstantBuffersState != NULL)
		context->VSSetConstantBuffers(0, D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT, vsConstantBuffersState);

#if (OVR_D3D_VERSION == 11)
	context->CSSetSamplers(0, D3D1x_COMMONSHADER_SAMPLER_SLOT_COUNT, csSamplerStates);
	if (csShaderResourceState != NULL)
		context->CSSetShaderResources(0, D3D1x_COMMONSHADER_INPUT_RESOURCE_SLOT_COUNT, csShaderResourceState);
	if (csConstantBuffersState != NULL)
		context->CSSetConstantBuffers(0, D3D1x_COMMONSHADER_CONSTANT_BUFFER_API_SLOT_COUNT, csConstantBuffersState);
	if (csUnorderedAccessViewState != NULL)
    	context->CSSetUnorderedAccessViews(0, D3D1x_SIMULTANEOUS_RENDER_TARGET_COUNT, csUnorderedAccessViewState, NULL);
#endif

	if (depthStencilViewState != NULL || renderTargetViewState != NULL)
		context->OMSetRenderTargets(D3D1x_SIMULTANEOUS_RENDER_TARGET_COUNT, renderTargetViewState, depthStencilViewState);

	if (omBlendState != NULL)
		context->OMSetBlendState(omBlendState, omBlendFactorState, omSampleMaskState);

	context->IASetPrimitiveTopology(primitiveTopologyState);

	if (iaIndexBufferPointerState != NULL)
		context->IASetIndexBuffer(iaIndexBufferPointerState, iaIndexBufferFormatState, iaIndexBufferOffsetState);

	if (iaVertexBufferPointersState != NULL)
		context->IASetVertexBuffers(0, D3D1x_IA_VERTEX_INPUT_RESOURCE_SLOT_COUNT, iaVertexBufferPointersState, iaVertexBufferStridesState, iaVertexBufferOffsetsState);

#if (OVR_D3D_VERSION == 10)
	if (currentPixelShader != NULL)
		context->PSSetShader(currentPixelShader);
	if (currentVertexShader != NULL)
		context->VSSetShader(currentVertexShader);
	if (currentGeometryShader != NULL)
		context->GSSetShader(currentGeometryShader);
#else
	if (currentPixelShader != NULL)
		context->PSSetShader(currentPixelShader, NULL, 0);
	if (currentVertexShader != NULL)
		context->VSSetShader(currentVertexShader, NULL, 0);
	if (currentGeometryShader != NULL)
		context->GSSetShader(currentGeometryShader, NULL, 0);
	if (currentHullShader != NULL)
		context->HSSetShader(currentHullShader, NULL, 0);
	if (currentDomainShader != NULL)
		context->DSSetShader(currentDomainShader, NULL, 0);
	if (currentComputeShader != NULL)
		context->CSSetShader(currentComputeShader, NULL, 0);
#endif
	clearMemory();
}

}}} // OVR::CAPI::D3D1X