OpenSpace/modules/globebrowsing/rendering/layershadermanager.cpp

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* OpenSpace                                                                             *
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* Copyright (c) 2014-2016                                                               *
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#include <modules/globebrowsing/rendering/layershadermanager.h>
#include <modules/globebrowsing/rendering/layermanager.h>

#include <openspace/rendering/renderengine.h>
#include <openspace/engine/openspaceengine.h>

#include "ghoul/misc/dictionary.h"

#include <string>

namespace {
    const std::string _loggerCat = "LayerShaderManager";
}

namespace openspace {
namespace globebrowsing {

    bool LayerGroupPreprocessingData::operator==(const LayerGroupPreprocessingData& other) const {
        return lastLayerIdx == other.lastLayerIdx &&
            layerBlendingEnabled == other.layerBlendingEnabled;
    }

    bool LayerShaderPreprocessingData::operator==(
        const LayerShaderPreprocessingData& other) const
    {
        
        if (layeredTextureInfo.size() != other.layeredTextureInfo.size() ||
            keyValuePairs.size() != other.keyValuePairs.size()) {
            return false;
        }
        else {
            bool equal = true;
            for (size_t i = 0; i < layeredTextureInfo.size(); i++) {
                equal &= (layeredTextureInfo[i] == other.layeredTextureInfo[i]);
            }
            for (size_t i = 0; i < keyValuePairs.size(); i++) {
                equal &= (keyValuePairs[i] == other.keyValuePairs[i]);
            }
            return equal;
        }
    }

    LayerShaderManager::LayerShaderManager(
        const std::string& shaderName,
        const std::string& vsPath,
        const std::string& fsPath)
        : _shaderName(shaderName)
        , _vsPath(vsPath)
        , _fsPath(fsPath)
        , _updatedOnLastCall(false)
    {

    }
    
    LayerShaderManager::~LayerShaderManager() {
        if (_programObject) {
            RenderEngine& renderEngine = OsEng.renderEngine();
            renderEngine.removeRenderProgram(_programObject);
            _programObject = nullptr;
        }
    }

    ProgramObject* LayerShaderManager::programObject(
        LayerShaderPreprocessingData preprocessingData)
    {
        _updatedOnLastCall = false;
        if (!(preprocessingData == _preprocessingData) || _programObject == nullptr) {
            recompileShaderProgram(preprocessingData);
            _updatedOnLastCall = true;
        }
        return _programObject.get();
    }

    void LayerShaderManager::recompileShaderProgram(
        LayerShaderPreprocessingData preprocessingData)
    {
        _preprocessingData = preprocessingData;
        ghoul::Dictionary shaderDictionary;
        

        // Different texture types can be height maps or color texture for example.
        // These are used differently within the shaders.
        auto textureTypes = _preprocessingData.layeredTextureInfo;
        for (size_t i = 0; i < textureTypes.size(); i++) {
            // lastLayerIndex must be at least 0 for the shader to compile,
            // the layer type is inactivated by setting use to false
            std::string groupName = LayerManager::LAYER_GROUP_NAMES[i];
            shaderDictionary.setValue("lastLayerIndex" + groupName, glm::max(textureTypes[i].lastLayerIdx, 0));
            shaderDictionary.setValue("use" + groupName, textureTypes[i].lastLayerIdx >= 0);
            shaderDictionary.setValue("blend" + groupName, textureTypes[i].layerBlendingEnabled);
        }

        // Other settings such as "useAtmosphere"
        auto keyValuePairs = _preprocessingData.keyValuePairs;
        for (size_t i = 0; i < keyValuePairs.size(); i++) {
            shaderDictionary.setValue(keyValuePairs[i].first, keyValuePairs[i].second);
        }

        // Remove old program
        OsEng.renderEngine().removeRenderProgram(_programObject);

        _programObject = OsEng.renderEngine().buildRenderProgram(
            _shaderName,
            _vsPath,
            _fsPath,
            shaderDictionary);

        ghoul_assert(_programObject != nullptr, "Failed to initialize programObject!");
        using IgnoreError = ProgramObject::IgnoreError;
        _programObject->setIgnoreSubroutineUniformLocationError(IgnoreError::Yes);
    }

    bool LayerShaderManager::updatedOnLastCall() {
        return _updatedOnLastCall;
    }

} // namespace globebrowsing
} // namespace openspace