// Created on: 2011-07-13
// Created by: Sergey ZERCHANINOV
// Copyright (c) 2011-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#ifndef OpenGl_AspectMarker_Header
#define OpenGl_AspectMarker_Header

#include <Aspect_TypeOfMarker.hxx>
#include <Graphic3d_AspectMarker3d.hxx>
#include <TCollection_AsciiString.hxx>

#include <OpenGl_Element.hxx>
#include <OpenGl_TextureSet.hxx>

class OpenGl_PointSprite;
class OpenGl_ShaderProgram;

//! The element holding Graphic3d_AspectMarker3d.
class OpenGl_AspectMarker : public OpenGl_Element
{
  DEFINE_STANDARD_RTTIEXT(OpenGl_AspectMarker, OpenGl_Element)
public:

  //! Empty constructor.
  Standard_EXPORT OpenGl_AspectMarker();

  //! Create and assign parameters.
  Standard_EXPORT OpenGl_AspectMarker (const Handle(Graphic3d_AspectMarker3d)& theAspect);

  //! Return the aspect.
  const Handle(Graphic3d_AspectMarker3d)& Aspect() const { return myAspect; }

  //! Assign new aspect.
  Standard_EXPORT void SetAspect (const Handle(Graphic3d_AspectMarker3d)& theAspect);

  //! @return marker size
  Standard_ShortReal MarkerSize() const { return myMarkerSize; }

  //! Init and return OpenGl point sprite resource.
  //! @return point sprite texture.
  const Handle(OpenGl_TextureSet)& SpriteRes (const Handle(OpenGl_Context)& theCtx) const
  {
    if (!myResources.IsSpriteReady())
    {
      myResources.BuildSprites (theCtx,
                                myAspect->GetMarkerImage(),
                                myAspect->Type(),
                                myAspect->Scale(),
                                myAspect->ColorRGBA(),
                                myMarkerSize);
      myResources.SetSpriteReady();
    }

    return myResources.Sprite();
  }

  //! Init and return OpenGl highlight point sprite resource.
  //! @return point sprite texture for highlight.
  const Handle(OpenGl_TextureSet)& SpriteHighlightRes (const Handle(OpenGl_Context)& theCtx) const
  {
    if (!myResources.IsSpriteReady())
    {
      myResources.BuildSprites (theCtx,
                                myAspect->GetMarkerImage(),
                                myAspect->Type(),
                                myAspect->Scale(),
                                myAspect->ColorRGBA(),
                                myMarkerSize);
      myResources.SetSpriteReady();
    }

    return myResources.SpriteA();
  }

  //! Init and return OpenGl shader program resource.
  //! @return shader program resource.
  const Handle(OpenGl_ShaderProgram)& ShaderProgramRes (const Handle(OpenGl_Context)& theCtx) const
  {
    if (!myResources.IsShaderReady())
    {
      myResources.BuildShader (theCtx, myAspect->ShaderProgram());
      myResources.SetShaderReady();
    }

    return myResources.ShaderProgram();
  }

  Standard_EXPORT virtual void Render  (const Handle(OpenGl_Workspace)& theWorkspace) const Standard_OVERRIDE;
  Standard_EXPORT virtual void Release (OpenGl_Context* theContext) Standard_OVERRIDE;

  //! Update presentation aspects parameters after their modification.
  virtual void SynchronizeAspects() Standard_OVERRIDE { SetAspect (myAspect); }

protected:

  //! OpenGl resources
  mutable struct Resources
  {
  public:

    //! Empty constructor.
    Resources()
    : myIsSpriteReady (Standard_False),
      myIsShaderReady (Standard_False) {}

    const Handle(OpenGl_TextureSet)&    Sprite()  const { return mySprite; }
    const Handle(OpenGl_TextureSet)&    SpriteA() const { return mySpriteA; }
    const Handle(OpenGl_ShaderProgram)& ShaderProgram() const { return myShaderProgram; }

    Standard_Boolean IsSpriteReady() const { return myIsSpriteReady; }
    Standard_Boolean IsShaderReady() const { return myIsShaderReady; }
    void SetSpriteReady() { myIsSpriteReady = Standard_True; }
    void SetShaderReady() { myIsShaderReady = Standard_True; }

    //! Update texture resource up-to-date state.
    Standard_EXPORT void UpdateTexturesRediness (const Handle(Graphic3d_AspectMarker3d)& theAspect,
                                                 Standard_ShortReal& theMarkerSize);

    //! Update shader resource up-to-date state.
    Standard_EXPORT void UpdateShaderRediness (const Handle(Graphic3d_AspectMarker3d)& theAspect);

    //! Release texture resource.
    Standard_EXPORT void ReleaseTextures (OpenGl_Context* theCtx);

    //! Release shader resource.
    Standard_EXPORT void ReleaseShaders (OpenGl_Context* theCtx);

    //! Build texture resources.
    Standard_EXPORT void BuildSprites (const Handle(OpenGl_Context)&        theCtx,
                                       const Handle(Graphic3d_MarkerImage)& theMarkerImage,
                                       const Aspect_TypeOfMarker            theType,
                                       const Standard_ShortReal             theScale,
                                       const Graphic3d_Vec4&                theColor,
                                       Standard_ShortReal&                  theMarkerSize);

    //! Build shader resources.
    Standard_EXPORT void BuildShader (const Handle(OpenGl_Context)&          theCtx,
                                      const Handle(Graphic3d_ShaderProgram)& theShader);

  private:

    //! Generate resource keys for a sprite.
    static void spriteKeys (const Handle(Graphic3d_MarkerImage)& theMarkerImage,
                            const Aspect_TypeOfMarker            theType,
                            const Standard_ShortReal             theScale,
                            const Graphic3d_Vec4&                theColor,
                            TCollection_AsciiString&             theKey,
                            TCollection_AsciiString&             theKeyA);

  private:

    Handle(OpenGl_TextureSet)      mySprite;
    Handle(OpenGl_TextureSet)      mySpriteA;
    Handle(OpenGl_ShaderProgram)   myShaderProgram;
    TCollection_AsciiString        myShaderProgramId;
    Standard_Boolean               myIsSpriteReady;
    Standard_Boolean               myIsShaderReady;

  } myResources;

  Handle(Graphic3d_AspectMarker3d) myAspect;
  mutable Standard_ShortReal       myMarkerSize;

public:

  DEFINE_STANDARD_ALLOC

};

#endif // OpenGl_AspectMarker_Header