Function getTruetypeTextBBoxCairo

mapcairo.c:390–458

#define CAIROLINESPACE 1.33

int getTruetypeTextBBoxCairo(rendererVTableObj *renderer, char *font, double size, char *text, rectObj *rect, double **advances) {
    
    
    cairoCacheData *cache = MS_RENDERER_CACHE(renderer);
    faceCacheObj *face = getFontFace(cache,font);
 
    char *utfptr=text;
    int i,has_kerning,unicode;
    unsigned long previdx=0;
    int numglyphs = msGetNumGlyphs(text);
    cairo_glyph_t glyph;
    cairo_text_extents_t extents;
    double px=0,py=0;

    if(face == NULL) {
        return MS_FAILURE;
    }

    cairo_set_font_face(cache->dummycr,face->face);
    cairo_set_font_size(cache->dummycr,size*96/72.0);

    has_kerning = FT_HAS_KERNING((face->ftface));

    if(advances != NULL) {
        *advances = (double*)malloc(numglyphs*sizeof(double));
    }

    for(i=0;i<numglyphs;i++) {
        utfptr+=msUTF8ToUniChar(utfptr, &unicode);
        glyph.x=px;
        glyph.y=py;
        if(unicode=='\n') {
            py += ceil(size*CAIROLINESPACE);
            px = 0;
            previdx=0;
            continue;
        }
        glyph.index = FT_Get_Char_Index(face->ftface, unicode);
        if( has_kerning && previdx ) {
            FT_Vector delta;
            FT_Get_Kerning( face->ftface, previdx, glyph.index, FT_KERNING_DEFAULT, &delta );
            px += delta.x / 64.;
        }
        cairo_glyph_extents(cache->dummycr,&glyph,1,&extents);
        
        if(i==0) {
            rect->minx = px+extents.x_bearing;
            rect->miny = py+extents.y_bearing;
            rect->maxx = px+extents.x_bearing+extents.width;
            rect->maxy = py+extents.y_bearing+extents.height;
        } else {
            rect->minx = MS_MIN(rect->minx,px+extents.x_bearing);
            rect->miny = MS_MIN(rect->miny,py+extents.y_bearing);
            rect->maxy = MS_MAX(rect->maxy,py+extents.y_bearing+extents.height);
            rect->maxx = MS_MAX(rect->maxx,px+extents.x_bearing+extents.width);
        }
        if(advances!=NULL)
            (*advances)[i]=extents.x_advance;