GLFontAtlas.h

#pragma once
#include <string>
#include <unordered_map>

#include "GLType.h"

namespace ParaEngine
{

    class Font;
    class Texture2D;
    class FontFreeType;

    class FontAtlas : public CRefCountedOne
    {
    public:
        static const int CacheTextureWidth;
        static const int CacheTextureHeight;
        static const char* CMD_PURGE_FONTATLAS;
        static const char* CMD_RESET_FONTATLAS;
        
        FontAtlas(Font &theFont);
        virtual ~FontAtlas();

        void addLetterDefinition(char16_t utf16Char, const FontLetterDefinition &letterDefinition);
        bool getLetterDefinitionForChar(char16_t utf16Char, FontLetterDefinition &letterDefinition);

        bool prepareLetterDefinitions(const std::u16string& utf16String);

        inline const std::unordered_map<size_t, Texture2D*>& getTextures() const { return _atlasTextures; }
        void  addTexture(Texture2D *texture, int slot);
        float getLineHeight() const { return _lineHeight; }
        void  setLineHeight(float newHeight);



        Texture2D* getTexture(int slot);
        const Font* getFont() const { return _font; }


        float getCommonLineHeight() const
        {
            return _lineHeight;
        }

        void purgeTexturesAtlas();

        void setAntiAliasTexParameters();

        void setAliasTexParameters();

    protected:
        void reset();

        void releaseTextures();

        void findNewCharacters(const std::u16string& u16Text, std::unordered_map<unsigned short, unsigned short>& charCodeMap);

        void conversionU16TOGB2312(const std::u16string& u16Text, std::unordered_map<unsigned short, unsigned short>& charCodeMap);

        void scaleFontLetterDefinition(float scaleFactor);

        std::unordered_map<size_t, Texture2D*> _atlasTextures;
        std::unordered_map<char16_t, FontLetterDefinition> _letterDefinitions;
        float _lineHeight;
        Font* _font;
        FontFreeType* _fontFreeType;
        void* _iconv;

        // Dynamic GlyphCollection related stuff
        int _currentPage;
        unsigned char *_currentPageData;
        int _currentPageDataSize;
        float _currentPageOrigX;
        float _currentPageOrigY;
        int _letterPadding;
        int _letterEdgeExtend;

        int _fontAscender;

        bool _antialiasEnabled;
        int _currLineHeight;

        friend class Label;
    };
}