IRenderer.hh

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/*===========================================================================*\
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 *   $Revision$                                                       *
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\*===========================================================================*/

#pragma once


#include <ACG/GL/gl.hh>
#include <ACG/Math/GLMatrixT.hh>
#include <ACG/GL/ShaderGenerator.hh>
#include <ACG/GL/RenderObject.hh>

#include <ACG/Scenegraph/SceneGraph.hh>
#include <ACG/Scenegraph/MaterialNode.hh>



namespace GLSL{
  class Program;
}

namespace ACG
{

// forward declaration
class VertexDeclaration;
class GLState;
class FBO;
class Texture;
class Texture2D;

namespace SceneGraph {
  namespace DrawModes {
    class DrawModeProperties;
  }
  class Material;
}

class ACGDLLEXPORT IRenderer
{
public:
  IRenderer();
  virtual ~IRenderer();


public:
  //=========================================================================
  // Callbacks for the scenegraph nodes
  //=========================================================================

  virtual void addRenderObject(RenderObject* _renderObject);

  struct LightData
  {
    LightData()
      : ltype(ACG::SG_LIGHT_DIRECTIONAL),
      diffuse(1.0f, 1.0f, 1.0f), ambient(1.0f, 1.0f, 1.0f), specular(1.0f, 1.0f, 1.0f),
      pos(0.0f, 0.0f, 0.0f), dir(1.0f, 0.0f, 0.0f), atten(1.0f, 0.0f, 0.0f), 
      spotCutoffExponent(0.0f, 0.0f)
    { }

    ACG::ShaderGenLightType ltype; // directional, spot- or pointlight
    ACG::Vec3f diffuse, ambient, specular; // light color factor
    ACG::Vec3f pos, dir; // position, direction in view-space
    ACG::Vec3f atten; // (constant, linear, quadratic) attenuation
    ACG::Vec2f spotCutoffExponent; // (cutoff angle, exponent) for spotlights
  };

  virtual void addLight(const LightData& _light);

  //=========================================================================
  // Render object collection and OpenGL setup for shader-based rendering
  //=========================================================================
protected:
  virtual void prepareRenderingPipeline(ACG::GLState* _glState, ACG::SceneGraph::DrawModes::DrawMode _drawMode, ACG::SceneGraph::BaseNode* _scenegraphRoot);

  virtual void collectRenderObjects(ACG::GLState* _glState, ACG::SceneGraph::DrawModes::DrawMode _drawMode, ACG::SceneGraph::BaseNode* _sceneGraphRoot);


  void traverseRenderableNodes(ACG::GLState* _glState, ACG::SceneGraph::DrawModes::DrawMode _drawMode, ACG::SceneGraph::BaseNode* _node, const ACG::SceneGraph::Material* _mat);



  //=========================================================================
  // Sorting
  //=========================================================================
protected:

    static int cmpPriority(const void*, const void*);


    virtual void sortRenderObjects();


  //=========================================================================
  // Rendering
  //=========================================================================
protected:

  virtual void renderObject(ACG::RenderObject* _obj, GLSL::Program* _prog = 0, bool _constRenderStates = false, const std::vector<unsigned int>* _shaderModifiers = 0);

  virtual void bindObjectVBO(ACG::RenderObject* _obj,
      GLSL::Program*     _prog);

  virtual void bindObjectUniforms(ACG::RenderObject* _obj,
      GLSL::Program*     _prog);

  virtual void bindObjectRenderStates(ACG::RenderObject* _obj);


  virtual void drawObject(ACG::RenderObject* _obj);


  //=========================================================================
  // Restore OpenGL State
  //=========================================================================

protected:


  virtual void finishRenderingPipeline(bool _drawOverlay = true);

  virtual void saveInputFbo();

  virtual void restoreInputFbo();

  virtual void saveActiveFbo(GLint* _outFboId, GLint* _outViewport, GLint* _outDrawBuffer) const;

  virtual void restoreFbo(GLint _fboId, const GLint* _outViewport, GLint _drawBuffer) const;

  virtual void clearInputFbo(const ACG::Vec4f& _clearColor);

  //=========================================================================
  // Other Convenience
  //=========================================================================

protected:

  virtual void copyDepthToBackBuffer(GLuint _depthTex, float _scale = 1.0f);

  
  virtual void renderDepthMap(int _viewerID, int _width, int _height);


  //=========================================================================
  // Internal shader modifiers
  //=========================================================================
protected:

  // depth map modifier: writes gl_FragCoord.z to red color channel
  class DepthMapPass : public ShaderModifier
  {
  public:
    void modifyFragmentEndCode(QStringList* _code);

    static DepthMapPass instance;
  };


  //=========================================================================
  // Debugging
  //=========================================================================
public:

  void dumpRenderObjectsToFile(const char* _fileName, ACG::RenderObject** _sortedList = 0) const;

  virtual QString dumpCurrentRenderObjectsToString(ACG::RenderObject** _list = 0, bool _outputShaders = false, std::vector<ACG::ShaderModifier*>* _modifiers = 0);

  void setErrorDetectionLevel(int _level);

  int getErrorDetectionLevel() const;

  //=========================================================================
  // Variables
  //=========================================================================
protected:

  int getNumRenderObjects() const;

  int getNumOverlayObjects() const;

  int getNumLineGL42Objects() const;

  int getNumLights() const;

  ACG::RenderObject* getRenderObject(int i);

  ACG::RenderObject* getOverlayRenderObject(int i);

  ACG::RenderObject* getLineGL42RenderObject(int i);

  LightData* getLight(int i);


  const ACG::Vec3f& getGlobalAmbientScale() const {return globalLightModelAmbient_;}


  void setLineThicknessRenderingGL42(bool _enable);


  //=========================================================================
  // Internally called by OpenFlipper core
  //=========================================================================
public:

  void setViewerID(int _viewerID);

protected:
  int numLights_;

  LightData lights_[SG_MAX_SHADER_LIGHTS];

  ACG::Vec3f globalLightModelAmbient_;

  std::vector<ACG::RenderObject> renderObjects_;


  std::vector<ACG::RenderObject*> sortedObjects_;

  std::vector<ACG::RenderObject*> overlayObjects_;

  std::map<int, ACG::FBO*> depthMaps_;

  bool depthMapUsed_;

  int curViewerID_;

  GLMatrixf viewMatrix_;

  Vec3f camPosWS_;

  Vec3f camDirWS_;

  GLint prevFbo_;

  GLint prevDrawBuffer_;

  GLint prevViewport_[4];

  bool prevFboSaved_;

  GLSL::Program* depthCopyShader_;

  int errorDetectionLevel_;

private:

  //=========================================================================
  // Default rendering of thick lines
  //=========================================================================

  bool enableLineThicknessGL42_;

  std::vector<RenderObject*> lineGL42Objects_;

  std::map< int, Texture* > lineColorBuffers_;

  void renderLineThicknessGL42();


};



//=============================================================================
} // namespace ACG
//=============================================================================