VisualImpactCalculatorOSG.h

#pragma once
//
// VisualImpactCalculatorOSG.h
//
// Framework for calculating visual impact of selected geometry in a scene.
// This code calculates the position of all the pixels that a particular set of
// drawing primitives has contributed to the frame buffer at the end of a rendering pass.
// i.e. All the pixels of a particular geometry or geometries that are visible in the current view.
// It then summates the solid angle that these pixels represent using Gauss Bonnett.
// This data can be used to give a quantatative assessment of the visual impact of the geometry.
//
// Contributed by Roger James (roger@beardandsandals.co.uk) and Virtual Outlooks Limited.
//
// Copyright (c) 2001-2012 Virtual Terrain Project
// Free for all uses, see license.txt for details.
//


class GDALRasterBand;

class CVisualImpactCalculatorOSG
{
public:
    CVisualImpactCalculatorOSG() : m_bInitialised(false) {};
    void AddVisualImpactContributor(osg::Node *pOsgNode);
    void RemoveVisualImpactContributor(osg::Node *pOsgNode);
    void SetVisualImpactTarget(const FPoint3 Target);
    const FPoint3& GetVisualImpactTarget() const;
    osg::Image* GetIntermediateImage() { return m_pIntermediateImage.get(); }
    osg::Image* GetFinalImage() { return m_pFinalImage.get(); }
    bool UsingLiveFrameBuffer();
    float Calculate();
    bool Plot(GDALRasterBand *pRasterBand, float fScaleFactor, double dXSampleInterval, double dYSampleInterval, bool progress_callback(int));
    bool Initialise();

protected:
    float Implementation(bool bOneOffMode, GDALRasterBand *pRasterBand = NULL, float fScaleFactor = 1.0f, double dXSampleInterval = 1.0f, double dYSampleInterval = 1.0f, bool progress_callback(int) = NULL);
    float InnerImplementation() const;
    FPoint3 m_Target;
    osg::Matrix m_ViewMatrix;
    mutable osg::Matrix m_ProjectionMatrix;
    mutable bool m_bUsingLiveFrameBuffer;
    mutable bool m_bInitialised;
    osg::ref_ptr<osg::Image> m_pIntermediateImage;
    osg::ref_ptr<osg::Image> m_pFinalImage;
    osg::ref_ptr<osg::Camera> m_pVisualImpactCamera;
    typedef std::set<osg::Node*> VisualImpactContributors;
    VisualImpactContributors m_VisualImpactContributors;
};