axmol/cocos/2d/CCFontFreeType.cpp

/****************************************************************************
Copyright (c) 2013      Zynga Inc.
Copyright (c) 2013-2014 Chukong Technologies Inc.
 
http://www.cocos2d-x.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
****************************************************************************/

#include <stdio.h>
#include <algorithm>

#include "ccUTF8.h"
#include "CCFontFreeType.h"
#include "2d/platform/CCFileUtils.h"
#include "edtaa3func.h"
#include FT_BBOX_H

NS_CC_BEGIN


FT_Library FontFreeType::_FTlibrary;
bool       FontFreeType::_FTInitialized = false;
const int  FontFreeType::DistanceMapSpread = 3;

typedef struct _DataRef
{
    Data data;
    unsigned int referenceCount;
}DataRef;

static std::unordered_map<std::string, DataRef> s_cacheFontData;

FontFreeType * FontFreeType::create(const std::string &fontName, int fontSize, GlyphCollection glyphs, const char *customGlyphs,bool distanceFieldEnabled /* = false */,int outline /* = 0 */)
{
    FontFreeType *tempFont =  new FontFreeType(distanceFieldEnabled,outline);

    if (!tempFont)
        return nullptr;
    
    tempFont->setCurrentGlyphCollection(glyphs, customGlyphs);
    
    if (!tempFont->createFontObject(fontName, fontSize))
    {
        delete tempFont;
        return nullptr;
    }
    return tempFont;
}

bool FontFreeType::initFreeType()
{
    if (_FTInitialized == false)
    {
        // begin freetype
        if (FT_Init_FreeType( &_FTlibrary ))
            return false;
        
        _FTInitialized = true;
    }
    
    return  _FTInitialized;
}

void FontFreeType::shutdownFreeType()
{
    if (_FTInitialized == true)
    {
        FT_Done_FreeType(_FTlibrary);
        _FTInitialized = false;
    }
}

FT_Library FontFreeType::getFTLibrary()
{
    initFreeType();
    return _FTlibrary;
}

FontFreeType::FontFreeType(bool distanceFieldEnabled /* = false */,int outline /* = 0 */)
: _fontRef(nullptr)
,_distanceFieldEnabled(distanceFieldEnabled)
,_outlineSize(outline)
,_stroker(nullptr)
{
    if (_outlineSize > 0)
    {
        FT_Stroker_New(FontFreeType::getFTLibrary(), &_stroker);
        FT_Stroker_Set(_stroker,
            (int)(_outlineSize * 64),
            FT_STROKER_LINECAP_ROUND,
            FT_STROKER_LINEJOIN_ROUND,
            0);
    }
}

bool FontFreeType::createFontObject(const std::string &fontName, int fontSize)
{
    FT_Face face;
    // save font name locally
    _fontName = fontName;

    auto it = s_cacheFontData.find(fontName);
    if (it != s_cacheFontData.end())
    {
        (*it).second.referenceCount += 1;
    }
    else
    {
        s_cacheFontData[fontName].referenceCount = 1;
        s_cacheFontData[fontName].data = FileUtils::getInstance()->getDataFromFile(fontName);    

        if (s_cacheFontData[fontName].data.isNull())
        {
            return false;
        }
    }

    if (FT_New_Memory_Face(getFTLibrary(), s_cacheFontData[fontName].data.getBytes(), s_cacheFontData[fontName].data.getSize(), 0, &face ))
        return false;
    
    //we want to use unicode
    if (FT_Select_Charmap(face, FT_ENCODING_UNICODE))
        return false;

    // set the requested font size
    int dpi = 72;
    int fontSizePoints = (int)(64.f * fontSize);
    if (FT_Set_Char_Size(face, fontSizePoints, fontSizePoints, dpi, dpi))
        return false;
    
    // store the face globally
    _fontRef = face;
    
    // done and good
    return true;
}

FontFreeType::~FontFreeType()
{
    if (_stroker)
    {
        FT_Stroker_Done(_stroker);
    }
    if (_fontRef)
    {
        FT_Done_Face(_fontRef);
    }

    s_cacheFontData[_fontName].referenceCount -= 1;
    if (s_cacheFontData[_fontName].referenceCount == 0)
    {
        s_cacheFontData.erase(_fontName);
    }
}

FontAtlas * FontFreeType::createFontAtlas()
{
    FontAtlas *atlas = new FontAtlas(*this);
    if (_usedGlyphs != GlyphCollection::DYNAMIC)
    {
        unsigned short* utf16 = cc_utf8_to_utf16(getCurrentGlyphCollection());
        atlas->prepareLetterDefinitions(utf16);
        CC_SAFE_DELETE_ARRAY(utf16);
    }
    this->release();
    return atlas;
}

int * FontFreeType::getHorizontalKerningForTextUTF16(unsigned short *text, int &outNumLetters) const
{
    if (!text || !_fontRef)
        return nullptr;
    
    outNumLetters = cc_wcslen(text);

    if (!outNumLetters)
        return nullptr;
    
    int *sizes = new int[outNumLetters];
    if (!sizes)
        return nullptr;
    memset(sizes,0,outNumLetters * sizeof(int));

    bool hasKerning = FT_HAS_KERNING( _fontRef ) != 0;
    if (hasKerning)
    {
        for (int c = 1; c < outNumLetters; ++c)
        {
            sizes[c] = getHorizontalKerningForChars(text[c-1], text[c]);
        }
    }
    
    return sizes;
}

int  FontFreeType::getHorizontalKerningForChars(unsigned short firstChar, unsigned short secondChar) const
{
    // get the ID to the char we need
    int glyphIndex1 = FT_Get_Char_Index(_fontRef, firstChar);
    
    if (!glyphIndex1)
        return 0;
    
    // get the ID to the char we need
    int glyphIndex2 = FT_Get_Char_Index(_fontRef, secondChar);
    
    if (!glyphIndex2)
        return 0;
    
    FT_Vector kerning;
    
    if (FT_Get_Kerning( _fontRef, glyphIndex1, glyphIndex2,  FT_KERNING_DEFAULT,  &kerning))
        return 0;
    
    return (static_cast<int>(kerning.x >> 6));
}

int FontFreeType::getFontMaxHeight() const
{
    return (static_cast<int>(_fontRef->size->metrics.height >> 6));
}

int FontFreeType::getFontAscender() const
{
    return (static_cast<int>(_fontRef->size->metrics.ascender >> 6));
}

unsigned char* FontFreeType::getGlyphBitmap(unsigned short theChar, long &outWidth, long &outHeight, Rect &outRect,int &xAdvance)
{
    bool invalidChar = true;
    unsigned char * ret = nullptr;

    do 
    {
        if (!_fontRef)
            break;

        auto glyphIndex = FT_Get_Char_Index(_fontRef, theChar);
        if(!glyphIndex)
            break;

        if (_distanceFieldEnabled)
        {
            if (FT_Load_Glyph(_fontRef,glyphIndex,FT_LOAD_RENDER | FT_LOAD_NO_HINTING | FT_LOAD_NO_AUTOHINT))
                break;
        }
        else
        {
            if (FT_Load_Glyph(_fontRef,glyphIndex,FT_LOAD_RENDER))
                break;
        }

        outRect.origin.x    = _fontRef->glyph->metrics.horiBearingX >> 6;
        outRect.origin.y    = - (_fontRef->glyph->metrics.horiBearingY >> 6);
        outRect.size.width  =   (_fontRef->glyph->metrics.width  >> 6);
        outRect.size.height =   (_fontRef->glyph->metrics.height >> 6);

        xAdvance = (static_cast<int>(_fontRef->glyph->metrics.horiAdvance >> 6));

        outWidth  = _fontRef->glyph->bitmap.width;
        outHeight = _fontRef->glyph->bitmap.rows;
        ret = _fontRef->glyph->bitmap.buffer;

        if (_outlineSize > 0)
        {
            auto copyBitmap = new unsigned char[outWidth * outHeight];
            memcpy(copyBitmap,ret,outWidth * outHeight * sizeof(unsigned char));

            long bitmapWidth;
            long bitmapHeight;
            FT_BBox bbox;
            auto outlineBitmap = getGlyphBitmapWithOutline(theChar,bbox);
            if(outlineBitmap == nullptr)
            {
                ret = nullptr;
                delete [] copyBitmap;
                break;
            }

            bitmapWidth = (bbox.xMax - bbox.xMin)>>6;
            bitmapHeight = (bbox.yMax - bbox.yMin)>>6;

            long index;
            auto blendImage = new unsigned char[bitmapWidth * bitmapHeight * 2];
            memset(blendImage, 0, bitmapWidth * bitmapHeight * 2);
            for (int x = 0; x < bitmapWidth; ++x)
            {
                for (int y = 0; y < bitmapHeight; ++y)
                {
                    index = x + ( y * bitmapWidth );
                    blendImage[2 * index] = outlineBitmap[index];
                }
            }

            long maxX = outWidth + _outlineSize;
            long maxY = outHeight + _outlineSize;
            for (int x = _outlineSize; x < maxX; ++x)
            {
                for (int y = _outlineSize; y < maxY; ++y)
                {
                    index = x + ( y * bitmapWidth );

                    blendImage[2 * index + 1] = copyBitmap[outWidth * (y - _outlineSize) + x - _outlineSize];
                }
            }

            outRect.origin.x = bbox.xMin >> 6;
            outRect.origin.y = - (bbox.yMax >> 6);

            xAdvance += bitmapWidth - outRect.size.width;

            outRect.size.width  =  bitmapWidth;
            outRect.size.height =  bitmapHeight;
            outWidth  = bitmapWidth;
            outHeight = bitmapHeight;

            delete [] outlineBitmap;
            delete [] copyBitmap;
            ret = blendImage;
        }

        invalidChar = false;
    } while (0);

    if (invalidChar)
    {
        outRect.size.width  = 0;
        outRect.size.height = 0;
        xAdvance = 0;

        return nullptr;
    }
    else
    {
       return ret;
    }
}

unsigned char * FontFreeType::getGlyphBitmapWithOutline(unsigned short theChar, FT_BBox &bbox)
{   
    unsigned char* ret = nullptr;

    FT_UInt gindex = FT_Get_Char_Index(_fontRef, theChar);
    if (FT_Load_Glyph(_fontRef, gindex, FT_LOAD_NO_BITMAP) == 0)
    {
        if (_fontRef->glyph->format == FT_GLYPH_FORMAT_OUTLINE)
        {
            FT_Glyph glyph;
            if (FT_Get_Glyph(_fontRef->glyph, &glyph) == 0)
            {
                FT_Glyph_StrokeBorder(&glyph, _stroker, 0, 1);
                if (glyph->format == FT_GLYPH_FORMAT_OUTLINE)
                {
                    FT_Outline *outline = &reinterpret_cast<FT_OutlineGlyph>(glyph)->outline;
                    FT_Glyph_Get_CBox(glyph,FT_GLYPH_BBOX_GRIDFIT,&bbox);
                    long width = (bbox.xMax - bbox.xMin)>>6;
                    long rows = (bbox.yMax - bbox.yMin)>>6;

                    FT_Bitmap bmp;
                    bmp.buffer = new unsigned char[width * rows];
                    memset(bmp.buffer, 0, width * rows);
                    bmp.width = (int)width;
                    bmp.rows = (int)rows;
                    bmp.pitch = (int)width;
                    bmp.pixel_mode = FT_PIXEL_MODE_GRAY;
                    bmp.num_grays = 256;

                    FT_Raster_Params params;
                    memset(&params, 0, sizeof (params));
                    params.source = outline;
                    params.target = &bmp;
                    params.flags = FT_RASTER_FLAG_AA;
                    FT_Outline_Translate(outline,-bbox.xMin,-bbox.yMin);
                    FT_Outline_Render(_FTlibrary, outline, &params);

                    ret = bmp.buffer;
                }
                FT_Done_Glyph(glyph);
            }
        }
    }

    return ret;
}

unsigned char * makeDistanceMap( unsigned char *img, long width, long height)
{
    long pixelAmount = (width + 2 * FontFreeType::DistanceMapSpread) * (height + 2 * FontFreeType::DistanceMapSpread);

    short * xdist = (short *)  malloc( pixelAmount * sizeof(short) );
    short * ydist = (short *)  malloc( pixelAmount * sizeof(short) );
    double * gx   = (double *) calloc( pixelAmount, sizeof(double) );
    double * gy      = (double *) calloc( pixelAmount, sizeof(double) );
    double * data    = (double *) calloc( pixelAmount, sizeof(double) );
    double * outside = (double *) calloc( pixelAmount, sizeof(double) );
    double * inside  = (double *) calloc( pixelAmount, sizeof(double) );
    long i,j;

    // Convert img into double (data) rescale image levels between 0 and 1
    long outWidth = width + 2 * FontFreeType::DistanceMapSpread;
    for (i = 0; i < width; ++i)
    {
        for (j = 0; j < height; ++j)
        {
            data[j * outWidth + FontFreeType::DistanceMapSpread + i] = img[j * width + i] / 255.0;
        }
    }

    width += 2 * FontFreeType::DistanceMapSpread;
    height += 2 * FontFreeType::DistanceMapSpread;

    // Transform background (outside contour, in areas of 0's)   
    computegradient( data, (int)width, (int)height, gx, gy);
    edtaa3(data, gx, gy, (int)width, (int)height, xdist, ydist, outside);
    for( i=0; i< pixelAmount; i++)
        if( outside[i] < 0.0 )
            outside[i] = 0.0;

    // Transform foreground (inside contour, in areas of 1's)   
    for( i=0; i< pixelAmount; i++)
        data[i] = 1 - data[i];
    computegradient( data, (int)width, (int)height, gx, gy);
    edtaa3(data, gx, gy, (int)width, (int)height, xdist, ydist, inside);
    for( i=0; i< pixelAmount; i++)
        if( inside[i] < 0.0 )
            inside[i] = 0.0;

    // The bipolar distance field is now outside-inside
    double dist;
    /* Single channel 8-bit output (bad precision and range, but simple) */    
    unsigned char *out = (unsigned char *) malloc( pixelAmount * sizeof(unsigned char) );
    for( i=0; i < pixelAmount; i++)
    {
        dist = outside[i] - inside[i];
        dist = 128.0 - dist*16;
        if( dist < 0 ) dist = 0;
        if( dist > 255 ) dist = 255;
        out[i] = (unsigned char) dist;
    }
    /* Dual channel 16-bit output (more complicated, but good precision and range) */
    /*unsigned char *out = (unsigned char *) malloc( pixelAmount * 3 * sizeof(unsigned char) ); 
    for( i=0; i< pixelAmount; i++)
    {
        dist = outside[i] - inside[i];
        dist = 128.0 - dist*16;
        if( dist < 0.0 ) dist = 0.0;
        if( dist >= 256.0 ) dist = 255.999;
        // R channel is a copy of the original grayscale image
        out[3*i] = img[i];
        // G channel is fraction
        out[3*i + 1] = (unsigned char) ( 256 - (dist - floor(dist)* 256.0 ));
        // B channel is truncated integer part
        out[3*i + 2] = (unsigned char)dist; 
    }*/
    
    free( xdist );
    free( ydist );
    free( gx );
    free( gy );
    free( data );
    free( outside );
    free( inside );

    return out;
}

void FontFreeType::renderCharAt(unsigned char *dest,int posX, int posY, unsigned char* bitmap,long bitmapWidth,long bitmapHeight)
{
    int iX = posX;
    int iY = posY;

    if (_distanceFieldEnabled)
    {
        auto distanceMap = makeDistanceMap(bitmap,bitmapWidth,bitmapHeight);

        bitmapWidth += 2 * DistanceMapSpread;
        bitmapHeight += 2 * DistanceMapSpread;

        for (long y = 0; y < bitmapHeight; ++y)
        {
            long bitmap_y = y * bitmapWidth;

            for (long x = 0; x < bitmapWidth; ++x)
            {    
                /* Dual channel 16-bit output (more complicated, but good precision and range) */
                /*int index = (iX + ( iY * destSize )) * 3;                
                int index2 = (bitmap_y + x)*3;
                dest[index] = out[index2];
                dest[index + 1] = out[index2 + 1];
                dest[index + 2] = out[index2 + 2];*/

                //Single channel 8-bit output 
                dest[iX + ( iY * FontAtlas::CacheTextureWidth )] = distanceMap[bitmap_y + x];

                iX += 1;
            }

            iX  = posX;
            iY += 1;
        }
        free(distanceMap);
    }
    else if(_outlineSize > 0)
    {
        unsigned char tempChar;
        for (long y = 0; y < bitmapHeight; ++y)
        {
            long bitmap_y = y * bitmapWidth;

            for (int x = 0; x < bitmapWidth; ++x)
            {
                tempChar = bitmap[(bitmap_y + x) * 2];
                dest[(iX + ( iY * FontAtlas::CacheTextureWidth ) ) * 2] = tempChar;
                tempChar = bitmap[(bitmap_y + x) * 2 + 1];
                dest[(iX + ( iY * FontAtlas::CacheTextureWidth ) ) * 2 + 1] = tempChar;

                iX += 1;
            }

            iX  = posX;
            iY += 1;
        }
        delete [] bitmap;
    }
    else
    {
        for (long y = 0; y < bitmapHeight; ++y)
        {
            long bitmap_y = y * bitmapWidth;

            for (int x = 0; x < bitmapWidth; ++x)
            {
                unsigned char cTemp = bitmap[bitmap_y + x];

                // the final pixel
                dest[(iX + ( iY * FontAtlas::CacheTextureWidth ) )] = cTemp;

                iX += 1;
            }

            iX  = posX;
            iY += 1;
        }
    } 
}

NS_CC_END