/*
-----------------------------------------------------------------------------
This source file is part of OGRE
(Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org

Copyright (c) 2000-2014 Torus Knot Software Ltd
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
-----------------------------------------------------------------------------
*/

#include "OgreShaderExLinearSkinning.h"
#ifdef RTSHADER_SYSTEM_BUILD_EXT_SHADERS
#include "OgreShaderFFPRenderState.h"
#include "OgreShaderProgram.h"
#include "OgreShaderParameter.h"
#include "OgreShaderProgramSet.h"
#include "OgreShaderGenerator.h"

#define HS_DATA_BIND_NAME "HS_SRS_DATA"


namespace Ogre {

namespace RTShader {


/************************************************************************/
/*                                                                      */
/************************************************************************/
LinearSkinning::LinearSkinning() : HardwareSkinningTechnique()
{
}

//-----------------------------------------------------------------------
bool LinearSkinning::resolveParameters(ProgramSet* programSet)
{

    Program* vsProgram = programSet->getCpuVertexProgram();
    Function* vsMain = vsProgram->getEntryPointFunction();

    //if needed mark this vertex program as hardware skinned
    if (mDoBoneCalculations == true)
    {
        vsProgram->setSkeletalAnimationIncluded(true);
    }

    //
    // get the parameters we need whether we are doing bone calculations or not
    //
    // Note: in order to be consistent we will always output position, normal,
    // tangent and binormal in both object and world space. And output position
    // in projective space to cover the responsibility of the transform stage

    //input param
    mParamInPosition = vsMain->resolveInputParameter(Parameter::SPS_POSITION, 0, Parameter::SPC_POSITION_OBJECT_SPACE, GCT_FLOAT4);
    mParamInNormal = vsMain->resolveInputParameter(Parameter::SPS_NORMAL, 0, Parameter::SPC_NORMAL_OBJECT_SPACE, GCT_FLOAT3);
    //mParamInBiNormal = vsMain->resolveInputParameter(Parameter::SPS_BINORMAL, 0, Parameter::SPC_BINORMAL_OBJECT_SPACE, GCT_FLOAT3);
    //mParamInTangent = vsMain->resolveInputParameter(Parameter::SPS_TANGENT, 0, Parameter::SPC_TANGENT_OBJECT_SPACE, GCT_FLOAT3);

    //local param
    mParamLocalPositionWorld = vsMain->resolveLocalParameter(Parameter::SPS_POSITION, 0, Parameter::SPC_POSITION_WORLD_SPACE, GCT_FLOAT4);
    mParamLocalNormalWorld = vsMain->resolveLocalParameter(Parameter::SPS_NORMAL, 0, Parameter::SPC_NORMAL_WORLD_SPACE, GCT_FLOAT3);
    mParamLocalNormal = vsMain->resolveLocalParameter(Parameter::SPS_NORMAL, 0, Parameter::SPC_NORMAL_OBJECT_SPACE, GCT_FLOAT3);
    //mParamLocalTangentWorld = vsMain->resolveLocalParameter(Parameter::SPS_TANGENT, 0, Parameter::SPC_TANGENT_WORLD_SPACE, GCT_FLOAT3);
    //mParamLocalBinormalWorld = vsMain->resolveLocalParameter(Parameter::SPS_BINORMAL, 0, Parameter::SPC_BINORMAL_WORLD_SPACE, GCT_FLOAT3);

    //output param
    mParamOutPositionProj = vsMain->resolveOutputParameter(Parameter::SPS_POSITION, 0, Parameter::SPC_POSITION_PROJECTIVE_SPACE, GCT_FLOAT4);

    //check if parameter retrival went well
    bool isValid =
        (mParamInPosition.get() != NULL) &&
        (mParamInNormal.get() != NULL) &&
        //(mParamInBiNormal.get() != NULL) &&
        //(mParamInTangent.get() != NULL) &&
        (mParamLocalPositionWorld.get() != NULL) &&
        (mParamLocalNormalWorld.get() != NULL) &&
        //(mParamLocalTangentWorld.get() != NULL) &&
        //(mParamLocalBinormalWorld.get() != NULL) &&
        (mParamOutPositionProj.get() != NULL);


    if (mDoBoneCalculations == true)
    {
        if (ShaderGenerator::getSingleton().getTargetLanguage() == "hlsl")
        {
            //set hlsl shader to use row-major matrices instead of column-major.
            //it enables the use of 3x4 matrices in hlsl shader instead of full 4x4 matrix.
            vsProgram->setUseColumnMajorMatrices(false);
        }

        //input parameters
        mParamInNormal = vsMain->resolveInputParameter(Parameter::SPS_NORMAL, 0, Parameter::SPC_NORMAL_OBJECT_SPACE, GCT_FLOAT3);
        //mParamInBiNormal = vsMain->resolveInputParameter(Parameter::SPS_BINORMAL, 0, Parameter::SPC_BINORMAL_OBJECT_SPACE, GCT_FLOAT3);
        //mParamInTangent = vsMain->resolveInputParameter(Parameter::SPS_TANGENT, 0, Parameter::SPC_TANGENT_OBJECT_SPACE, GCT_FLOAT3);
        mParamInIndices = vsMain->resolveInputParameter(Parameter::SPS_BLEND_INDICES, 0, Parameter::SPC_BLEND_INDICES, GCT_FLOAT4);
        mParamInWeights = vsMain->resolveInputParameter(Parameter::SPS_BLEND_WEIGHTS, 0, Parameter::SPC_BLEND_WEIGHTS, GCT_FLOAT4);
        mParamInWorldMatrices = vsProgram->resolveAutoParameterInt(GpuProgramParameters::ACT_WORLD_MATRIX_ARRAY_3x4, 0, mBoneCount);
        mParamInInvWorldMatrix = vsProgram->resolveAutoParameterInt(GpuProgramParameters::ACT_INVERSE_WORLD_MATRIX, 0);
        mParamInViewProjMatrix = vsProgram->resolveAutoParameterInt(GpuProgramParameters::ACT_VIEWPROJ_MATRIX, 0);

        mParamTempFloat4 = vsMain->resolveLocalParameter(Parameter::SPS_UNKNOWN, -1, "TempVal4", GCT_FLOAT4);
        mParamTempFloat3 = vsMain->resolveLocalParameter(Parameter::SPS_UNKNOWN, -1, "TempVal3", GCT_FLOAT3);

        //check if parameter retrival went well
        isValid &=
            (mParamInIndices.get() != NULL) &&
            (mParamInWeights.get() != NULL) &&
            (mParamInWorldMatrices.get() != NULL) &&
            (mParamInViewProjMatrix.get() != NULL) &&
            (mParamInInvWorldMatrix.get() != NULL) &&
            (mParamTempFloat4.get() != NULL) &&
            (mParamTempFloat3.get() != NULL);
    }
    else
    {
        mParamInWorldMatrix = vsProgram->resolveAutoParameterInt(GpuProgramParameters::ACT_WORLD_MATRIX, 0);
        mParamInWorldViewProjMatrix = vsProgram->resolveAutoParameterInt(GpuProgramParameters::ACT_WORLDVIEWPROJ_MATRIX, 0);

        //check if parameter retrival went well
        isValid &=
            (mParamInWorldMatrix.get() != NULL) &&
            (mParamInWorldViewProjMatrix.get() != NULL);
    }
    return isValid;
}

//-----------------------------------------------------------------------
bool LinearSkinning::resolveDependencies(ProgramSet* programSet)
{
    Program* vsProgram = programSet->getCpuVertexProgram();
    vsProgram->addDependency(FFP_LIB_COMMON);
    vsProgram->addDependency(FFP_LIB_TRANSFORM);

    return true;
}

//-----------------------------------------------------------------------
bool LinearSkinning::addFunctionInvocations(ProgramSet* programSet)
{

    Program* vsProgram = programSet->getCpuVertexProgram();
    Function* vsMain = vsProgram->getEntryPointFunction();
    int internalCounter = 0;

    //add functions to calculate position data in world, object and projective space
    addPositionCalculations(vsMain, internalCounter);

    //add functions to calculate normal and normal related data in world and object space
    addNormalRelatedCalculations(vsMain, mParamInNormal, mParamLocalNormal, mParamLocalNormalWorld, internalCounter);
    //addNormalRelatedCalculations(vsMain, mParamInTangent, mParamLocalTangentWorld, internalCounter);
    //addNormalRelatedCalculations(vsMain, mParamInBiNormal, mParamLocalBinormalWorld, internalCounter);
    return true;
}

//-----------------------------------------------------------------------
void LinearSkinning::addPositionCalculations(Function* vsMain, int& funcCounter)
{
    FunctionInvocation* curFuncInvocation = NULL;

    if (mDoBoneCalculations == true)
    {
        //set functions to calculate world position
        for(int i = 0 ; i < getWeightCount() ; ++i)
        {
            addIndexedPositionWeight(vsMain, i, funcCounter);
        }

        //update back the original position relative to the object
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamInInvWorldMatrix, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamLocalPositionWorld, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamInPosition, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);

        //update the projective position thereby filling the transform stage role
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamInViewProjMatrix, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamLocalPositionWorld, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamOutPositionProj, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
    else
    {
        //update from object to world space
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamInWorldMatrix, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamInPosition, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamLocalPositionWorld, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);

        //update from object to projective space
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamInWorldViewProjMatrix, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamInPosition, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamOutPositionProj, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
}

//-----------------------------------------------------------------------
void LinearSkinning::addNormalRelatedCalculations(Function* vsMain,
                                ParameterPtr& pNormalIn,
                                ParameterPtr& pNormalRelatedParam,
                                ParameterPtr& pNormalWorldRelatedParam,
                                int& funcCounter)
{
    FunctionInvocation* curFuncInvocation;

    // allow writing to normal parameter
    curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_ASSIGN, FFP_VS_TRANSFORM, funcCounter++);
    curFuncInvocation->pushOperand(pNormalIn, Operand::OPS_IN);
    curFuncInvocation->pushOperand(pNormalRelatedParam, Operand::OPS_OUT);
    vsMain->addAtomInstance(curFuncInvocation);

    if (mDoBoneCalculations == true)
    {
        //set functions to calculate world normal
        for(int i = 0 ; i < getWeightCount() ; ++i)
        {
            addIndexedNormalRelatedWeight(vsMain, pNormalRelatedParam, pNormalWorldRelatedParam, i, funcCounter);
        }

        //update back the original position relative to the object
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamInInvWorldMatrix, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalWorldRelatedParam, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalRelatedParam, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
    else
    {
        //update from object to world space
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamInWorldMatrix, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalRelatedParam, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalWorldRelatedParam, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }

}

//-----------------------------------------------------------------------
void LinearSkinning::addIndexedPositionWeight(Function* vsMain,
                                int index, int& funcCounter)
{
    Operand::OpMask indexMask = indexToMask(index);

    FunctionInvocation* curFuncInvocation;

    //multiply position with world matrix and put into temporary param
    curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
    curFuncInvocation->pushOperand(mParamInWorldMatrices, Operand::OPS_IN);
    curFuncInvocation->pushOperand(mParamInIndices, Operand::OPS_IN,  indexMask, 1);
    curFuncInvocation->pushOperand(mParamInPosition, Operand::OPS_IN);
    curFuncInvocation->pushOperand(mParamTempFloat4, Operand::OPS_OUT, Operand::OPM_XYZ);
    vsMain->addAtomInstance(curFuncInvocation);

    //set w value of temporary param to 1
    curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_ASSIGN, FFP_VS_TRANSFORM, funcCounter++);
    curFuncInvocation->pushOperand(ParameterFactory::createConstParamFloat(1.0f), Operand::OPS_IN);
    curFuncInvocation->pushOperand(mParamTempFloat4, Operand::OPS_OUT, Operand::OPM_W);
    vsMain->addAtomInstance(curFuncInvocation);

    //multiply temporary param with  weight
    curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_MODULATE, FFP_VS_TRANSFORM, funcCounter++);
    curFuncInvocation->pushOperand(mParamTempFloat4, Operand::OPS_IN);
    curFuncInvocation->pushOperand(mParamInWeights, Operand::OPS_IN, indexMask);
    curFuncInvocation->pushOperand(mParamTempFloat4, Operand::OPS_OUT);
    vsMain->addAtomInstance(curFuncInvocation);

    //check if on first iteration
    if (index == 0)
    {
        //set the local param as the value of the world param
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_ASSIGN, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamTempFloat4, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamLocalPositionWorld, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
    else
    {
        //add the local param as the value of the world param
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_ADD, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamTempFloat4, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamLocalPositionWorld, Operand::OPS_IN);
        curFuncInvocation->pushOperand(mParamLocalPositionWorld, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
}


//-----------------------------------------------------------------------
void LinearSkinning::addIndexedNormalRelatedWeight(Function* vsMain,
                                ParameterPtr& pNormalParam,
                                ParameterPtr& pNormalWorldRelatedParam,
                                int index, int& funcCounter)
{

    FunctionInvocation* curFuncInvocation;

    Operand::OpMask indexMask = indexToMask(index);

    //multiply position with world matrix and put into temporary param
    curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_TRANSFORM, FFP_VS_TRANSFORM, funcCounter++);
    curFuncInvocation->pushOperand(mParamInWorldMatrices, Operand::OPS_IN, Operand::OPM_ALL);
    curFuncInvocation->pushOperand(mParamInIndices, Operand::OPS_IN,  indexMask, 1);
    curFuncInvocation->pushOperand(pNormalParam, Operand::OPS_IN);
    curFuncInvocation->pushOperand(mParamTempFloat3, Operand::OPS_OUT);
    vsMain->addAtomInstance(curFuncInvocation);

    //multiply temporary param with weight
    curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_MODULATE, FFP_VS_TRANSFORM, funcCounter++);
    curFuncInvocation->pushOperand(mParamTempFloat3, Operand::OPS_IN);
    curFuncInvocation->pushOperand(mParamInWeights, Operand::OPS_IN, indexMask);
    curFuncInvocation->pushOperand(mParamTempFloat3, Operand::OPS_OUT);
    vsMain->addAtomInstance(curFuncInvocation);

    //check if on first iteration
    if (index == 0)
    {
        //set the local param as the value of the world normal
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_ASSIGN, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamTempFloat3, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalWorldRelatedParam, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
    else
    {
        //add the local param as the value of the world normal
        curFuncInvocation = OGRE_NEW FunctionInvocation(FFP_FUNC_ADD, FFP_VS_TRANSFORM, funcCounter++);
        curFuncInvocation->pushOperand(mParamTempFloat3, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalWorldRelatedParam, Operand::OPS_IN);
        curFuncInvocation->pushOperand(pNormalWorldRelatedParam, Operand::OPS_OUT);
        vsMain->addAtomInstance(curFuncInvocation);
    }
}

}
}

#endif