OpenSpace/modules/globebrowsing/src/shadowcomponent.h

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 * OpenSpace                                                                             *
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 * Copyright (c) 2014-2022                                                               *
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#ifndef __OPENSPACE_MODULE_GLOBEBROWSING___SHADOWCOMPONENT___H__
#define __OPENSPACE_MODULE_GLOBEBROWSING___SHADOWCOMPONENT___H__

#include <openspace/properties/propertyowner.h>

#include <openspace/camera/camera.h>
#include <openspace/properties/stringproperty.h>
#include <openspace/properties/triggerproperty.h>
#include <openspace/properties/scalar/boolproperty.h>
#include <openspace/properties/scalar/floatproperty.h>
#include <openspace/properties/scalar/intproperty.h>
#include <openspace/properties/vector/vec2property.h>
#include <openspace/properties/vector/vec4property.h>
#include <ghoul/glm.h>
#include <ghoul/opengl/texture.h>
#include <ghoul/opengl/uniformcache.h>
#include <string>
#include <sstream>

namespace ghoul { class Dictionary; }
namespace ghoul::filesystem { class File; }
namespace ghoul::opengl { class ProgramObject; }

namespace openspace {
    struct RenderData;
    struct UpdateData;

namespace documentation { struct Documentation; }

class ShadowComponent : public properties::PropertyOwner {
public:
    struct ShadowMapData {
        glm::dmat4 shadowMatrix = glm::dmat4(1.0);
        GLuint shadowDepthTexture = 0;
    };

    ShadowComponent(const ghoul::Dictionary& dictionary);

    void initialize();
    void initializeGL();
    void deinitializeGL();
    //bool deinitialize();

    bool isReady() const;

    RenderData begin(const RenderData& data);
    void end();
    void update(const UpdateData& data);

    static documentation::Documentation Documentation();

    bool isEnabled() const;

    ShadowComponent::ShadowMapData shadowMapData() const;

    GLuint dDepthTexture() const;

private:
    void createDepthTexture();
    void createShadowFBO();
    void updateDepthTexture();
    void buildDDepthTexture();

    // Debug
    void saveDepthBuffer();

    ShadowMapData _shadowData;

    // Texture coords in [0, 1], while clip coords in [-1, 1]
    const glm::dmat4 _toTextureCoordsMatrix = glm::dmat4(
        glm::dvec4(0.5, 0.0, 0.0, 0.0),
        glm::dvec4(0.0, 0.5, 0.0, 0.0),
        glm::dvec4(0.0, 0.0, 1.0, 0.0),
        glm::dvec4(0.5, 0.5, 0.0, 1.0)
    );

    // DEBUG
    properties::TriggerProperty _saveDepthTexture;
    properties::IntProperty _distanceFraction;
    properties::BoolProperty _enabled;

    int _shadowDepthTextureHeight = 4096;
    int _shadowDepthTextureWidth = 4096;
    bool _dynamicDepthTextureRes = true;

    GLuint _shadowDepthTexture = 0;
    // JCC: Used to avoid recompilation of Globebrowsing's shaders
    // and incorrect binding of texture type
    GLuint _dDepthTexture = 0;
    GLuint _positionInLightSpaceTexture = 0;
    GLuint _shadowFBO = 0;
    GLint _currentFBO = 0;
    GLint _mViewport[4];

    GLboolean _faceCulling;
    GLboolean _polygonOffSet;
    GLboolean _depthIsEnabled;
    GLboolean _blendIsEnabled = false;

    glm::vec3 _sunPosition = glm::vec3(0.f);

    glm::dmat4 _shadowMatrix = glm::dmat4(1.0);

    glm::dvec3 _cameraPos = glm::dvec3(0.0);
    glm::dvec3 _cameraFocus = glm::dvec3(0.0);
    glm::dquat _cameraRotation = glm::dquat(1.0, 0.0, 0.0, 0.0);

    std::stringstream _serializedCamera;

    std::unique_ptr<Camera> _lightCamera;

    // DEBUG
    bool _executeDepthTextureSave = false;
};

} // namespace openspace

#endif // __OPENSPACE_MODULE_GLOBEBROWSING___SHADOWCOMPONENT___H__