// Created on: 2015-06-18
// Created by: Ilya SEVRIKOV
// Copyright (c) 2015 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_TextBuilder_Header
#define OpenGl_TextBuilder_Header

#include "OpenGl_Font.hxx"
#include "OpenGl_VertexBuffer.hxx"
#include "OpenGl_VertexBufferEditor.hxx"
#include "OpenGl_Vec.hxx"

#include "NCollection_DynamicArray.hxx"
#include "NCollection_Handle.hxx"

class Font_TextFormatter;

//! This class generates primitive array required for rendering textured text using OpenGl_Font
//! instance.
class OpenGl_TextBuilder
{
public:
  //! Creates empty object.
  Standard_EXPORT OpenGl_TextBuilder();

  //! Creates texture quads for the given text.
  Standard_EXPORT void Perform(
    const occ::handle<Font_TextFormatter>&                      theFormatter,
    const occ::handle<OpenGl_Context>&                          theContext,
    OpenGl_Font&                                                theFont,
    NCollection_DynamicArray<GLuint>&                           theTextures,
    NCollection_DynamicArray<occ::handle<OpenGl_VertexBuffer>>& theVertsPerTexture,
    NCollection_DynamicArray<occ::handle<OpenGl_VertexBuffer>>& theTCrdsPerTexture);

protected: //! @name class auxiliary methods
  Standard_EXPORT void createGlyphs(
    const occ::handle<Font_TextFormatter>& theFormatter,
    const occ::handle<OpenGl_Context>&     theCtx,
    OpenGl_Font&                           theFont,
    NCollection_DynamicArray<GLuint>&      theTextures,
    NCollection_DynamicArray<NCollection_Handle<NCollection_DynamicArray<NCollection_Vec2<float>>>>&
      theVertsPerTexture,
    NCollection_DynamicArray<NCollection_Handle<NCollection_DynamicArray<NCollection_Vec2<float>>>>&
      theTCrdsPerTexture);

protected: //! @name class auxiliary fields
  NCollection_DynamicArray<OpenGl_Font::Tile>        myTileRects;
  OpenGl_VertexBufferEditor<NCollection_Vec2<float>> myVboEditor;
};

#endif // OpenGl_TextBuilder_Header