TerrainShader.h

/*
 * Copyright (C) 2014 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * 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.
 */

#ifndef TERRAINSHADER_H
#define TERRAINSHADER_H

#include <memory>
#include "TerrainMaterialDef.h"
#include "renderer/InstancedShader.h"
#include "renderer/RendererCommon.h"

struct TerrainShaderKey {
    bool hasEdge = false;
    bool hasBevel = false;
    TerrainMaterialDef::BlendMode blendMode = TerrainMaterialDef::BlendMode::Add;

    bool operator < (const TerrainShaderKey& other) const;
    TerrainShaderKey();
    TerrainShaderKey(bool hasEdge, bool hasBevel, TerrainMaterialDef::BlendMode blendMode);
};

class TerrainShader;
typedef std::shared_ptr<TerrainShader> TerrainShaderPtr;

class TerrainShader : public InstancedShader {
public:
    explicit TerrainShader(const ShaderPtr& sharedShader);

    const TexturePtr& getBaseTexture() const { return mBaseTexture; }
    void setBaseTexture(const TexturePtr& value);
    const TexturePtr& getMaskTexture() const { return mMaskTexture; }
    void setMaskTexture(const TexturePtr& value);
    const TexturePtr& getBlendTexture() const { return mBlendTexture; }
    void setBlendTexture(const TexturePtr& value);

    void setTransform(const Matrix4& matrix);

    static const ShaderPtr& getSharedShader(const TerrainShaderKey& shaderKey);

protected:
    virtual void updateState() override;

private:
    static void addShaderCodeDefines(const TerrainShaderKey& shaderKey, std::string& code);
    static void initializeShaderMap();
    static ShaderPtr createSharedShader(const TerrainShaderKey& shaderKey);

    static bool sShaderMapInitialized;
    // Note: The data in this map is intentionally leaked. Used very late in rendering.
    static QMap<TerrainShaderKey, ShaderPtr> sShaderMap;

    TexturePtr mBaseTexture;
    TexturePtr mMaskTexture;
    TexturePtr mBlendTexture;
    Matrix4 mTransform;

    static const char* TERRAIN_SHADER_UNIFORMS[];
    static const char* VERTEX_SHADER_PATH;
    static const char* FRAGMENT_SHADER_PATH;
};

#endif // TERRAINSHADER_H