// This file is part of the OGRE project.

// It is subject to the license terms in the LICENSE file found in the top-level directory

// of this distribution and at https://www.ogre3d.org/licensing.

// SPDX-License-Identifier: MIT

#ifndef _ShaderTerrainTransform_

#define _ShaderTerrainTransform_

#include "OgreTerrainPrerequisites.h"

#include "OgreShaderSubRenderState.h"

#include "OgreShaderParameter.h"

#include "OgreShaderFFPRenderState.h"

#include "OgreTerrain.h"

namespace Ogre {

class TerrainTransform : public RTShader::SubRenderState

{

public:

    const String& getType() const override { return Type; }

    int getExecutionOrder() const override { return RTShader::FFP_TRANSFORM; }

    void copyFrom(const SubRenderState& rhs) override {}

    bool createCpuSubPrograms(RTShader::ProgramSet* programSet) override;

    bool preAddToRenderState(const RTShader::RenderState* renderState, Pass* srcPass, Pass* dstPass) override;

    void updateParams();

    static String Type;

private:

    const Terrain* mTerrain;

    bool mCompressed = false;

    Terrain::Alignment mAlign = Terrain::ALIGN_X_Z;

    RTShader::UniformParameterPtr mPointTrans;

    RTShader::UniformParameterPtr mBaseUVScale;

};

class TerrainSurface : public RTShader::SubRenderState

{

public:

    const String& getType() const override { return Type; }

    int getExecutionOrder() const override { return RTShader::FFP_LIGHTING - 1; }

    void copyFrom(const SubRenderState& rhs) override

    {

        mUseNormalMapping = static_cast<const TerrainSurface&>(rhs).mUseNormalMapping;

    }

    bool createCpuSubPrograms(RTShader::ProgramSet* programSet) override;

    bool preAddToRenderState(const RTShader::RenderState* renderState, Pass* srcPass, Pass* dstPass) override;

    void updateParams();

    bool setParameter(const String& name, const String& value) override;

    static String Type;

protected:

    const Terrain* mTerrain;

    std::vector<RTShader::UniformParameterPtr> mUVMul;

    bool mUseNormalMapping = true;

    bool mUseSpecularMapping = false;

    bool mUseParallaxMapping = false;

    bool mUseParallaxOcclusionMapping = false;

    bool mForCompositeMap = false;

    int mNumLayers = 0;

};

class TerrainSurfaceFactory : public RTShader::SubRenderStateFactory

{

public:

    const String& getType() const override;

protected:

    RTShader::SubRenderState* createInstanceImpl() override;

};

class TerrainTransformFactory : public RTShader::SubRenderStateFactory

{

public:

    const String& getType() const override;

protected:

    RTShader::SubRenderState* createInstanceImpl() override;

};

}

#endif