web2c/xetexdir/XeTeXFontMgr.cpp

/****************************************************************************\
 Part of the XeTeX typesetting system
 Copyright (c) 1994-2008 by SIL International
 Copyright (c) 2009-2014 by Jonathan Kew

 SIL Author(s): Jonathan Kew

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"Software"), to deal in the Software without restriction, including
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FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
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#include <w2c/config.h>

#include "XeTeX_web.h"

#ifdef XETEX_MAC
#include "XeTeXFontMgr_Mac.h"
#else
#include "XeTeXFontMgr_FC.h"
#endif
#include "XeTeXFontInst.h"

#include <hb-ot.h>

// see cpascal.h
#define printcstring(STR)        \
  do {                           \
    const char* ch_ptr = (STR);  \
    while (*ch_ptr)              \
      zprintchar(*(ch_ptr++));    \
  } while (0)

XeTeXFontMgr* XeTeXFontMgr::sFontManager = NULL;
char XeTeXFontMgr::sReqEngine = 0;

/* use our own fmax function because it seems to be missing on certain platforms
   (solaris2.9, at least) */
static inline double
my_fmax(double x, double y)
{
    return (x > y) ? x : y;
}

XeTeXFontMgr*
XeTeXFontMgr::GetFontManager()
{
    if (sFontManager == NULL) {
#ifdef XETEX_MAC
        sFontManager = new XeTeXFontMgr_Mac;
#else
        sFontManager = new XeTeXFontMgr_FC;
#endif
        sFontManager->initialize();
    }

    return sFontManager;
}

void
XeTeXFontMgr::Terminate()
{
    if (sFontManager != NULL) {
        sFontManager->terminate();
        // we don't actually deallocate the manager, just ask it to clean up
        // any auxiliary data such as the cocoa pool or freetype/fontconfig stuff
        // as we still need to access font names after this is called
    }
}

PlatformFontRef
XeTeXFontMgr::findFont(const char* name, char* variant, double ptSize)
    // ptSize is in TeX points, or negative for 'scaled' factor
    // "variant" string will be shortened (in-place) by removal of /B and /I if present
{
    std::string nameStr(name);
    Font* font = NULL;
    int dsize = 100;
    loadedfontdesignsize = 655360L;

    for (int pass = 0; pass < 2; ++pass) {
        // try full name as given
        std::map<std::string,Font*>::iterator i = m_nameToFont.find(nameStr);
        if (i != m_nameToFont.end()) {
            font = i->second;
            if (font->opSizeInfo.designSize != 0)
                dsize = font->opSizeInfo.designSize;
            break;
        }

        // if there's a hyphen, split there and try Family-Style
        int hyph = nameStr.find('-');
        if (hyph > 0 && hyph < nameStr.length() - 1) {
            std::string family(nameStr.begin(), nameStr.begin() + hyph);
            std::map<std::string,Family*>::iterator f = m_nameToFamily.find(family);
            if (f != m_nameToFamily.end()) {
                std::string style(nameStr.begin() + hyph + 1, nameStr.end());
                i = f->second->styles->find(style);
                if (i != f->second->styles->end()) {
                    font = i->second;
                    if (font->opSizeInfo.designSize != 0)
                        dsize = font->opSizeInfo.designSize;
                    break;
                }
            }
        }

        // try as PostScript name
        i = m_psNameToFont.find(nameStr);
        if (i != m_psNameToFont.end()) {
            font = i->second;
            if (font->opSizeInfo.designSize != 0)
                dsize = font->opSizeInfo.designSize;
            break;
        }

        // try for the name as a family name
        std::map<std::string,Family*>::iterator f = m_nameToFamily.find(nameStr);

        if (f != m_nameToFamily.end()) {
            // look for a family member with the "regular" bit set in OS/2
            int regFonts = 0;
            for (i = f->second->styles->begin(); i != f->second->styles->end(); ++i)
                if (i->second->isReg) {
                    if (regFonts == 0)
                        font = i->second;
                    ++regFonts;
                }

            // families with Ornament or similar fonts may flag those as Regular,
            // which confuses the search above... so try some known names
            if (font == NULL || regFonts > 1) {
                // try for style "Regular", "Plain", "Normal", "Roman"
                i = f->second->styles->find("Regular");
                if (i != f->second->styles->end())
                    font = i->second;
                else {
                    i = f->second->styles->find("Plain");
                    if (i != f->second->styles->end())
                        font = i->second;
                    else {
                        i = f->second->styles->find("Normal");
                        if (i != f->second->styles->end())
                            font = i->second;
                        else {
                            i = f->second->styles->find("Roman");
                            if (i != f->second->styles->end())
                                font = i->second;
                        }
                    }
                }
            }

            if (font == NULL) {
                // look through the family for the (weight, width, slant) nearest to (80, 100, 0)
                font = bestMatchFromFamily(f->second, 80, 100, 0);
            }

            if (font != NULL)
                break;
        }

        if (pass == 0) {
            // didn't find it in our caches, so do a platform search (may be relatively expensive);
            // this will update the caches with any fonts that seem to match the name given,
            // so that the second pass might find it
            searchForHostPlatformFonts(nameStr);
        }
    }

    if (font == NULL)
        return 0;

    Family* parent = font->parent;

    // if there are variant requests, try to apply them
    // and delete B, I, and S=... codes from the string, just retain /engine option
    sReqEngine = 0;
    bool reqBold = false;
    bool reqItal = false;
    if (variant != NULL) {
        std::string varString;
        char* cp = variant;
        while (*cp) {
            if (strncmp(cp, "AAT", 3) == 0) {
                sReqEngine = 'A';
                cp += 3;
                if (varString.length() > 0 && *(varString.end() - 1) != '/')
                    varString.append("/");
                varString.append("AAT");
                goto skip_to_slash;
            }
            if (strncmp(cp, "ICU", 3) == 0) { // for backword compatability
                sReqEngine = 'O';
                cp += 3;
                if (varString.length() > 0 && *(varString.end() - 1) != '/')
                    varString.append("/");
                varString.append("OT");
                goto skip_to_slash;
            }
            if (strncmp(cp, "OT", 2) == 0) {
                sReqEngine = 'O';
                cp += 2;
                if (varString.length() > 0 && *(varString.end() - 1) != '/')
                    varString.append("/");
                varString.append("OT");
                goto skip_to_slash;
            }
            if (strncmp(cp, "GR", 2) == 0) {
                sReqEngine = 'G';
                cp += 2;
                if (varString.length() > 0 && *(varString.end() - 1) != '/')
                    varString.append("/");
                varString.append("GR");
                goto skip_to_slash;
            }
            if (*cp == 'S') {
                char* start = cp;
                ++cp;
                if (*cp == '=')
                    ++cp;
                ptSize = 0.0;
                while (*cp >= '0' && *cp <= '9') {
                    ptSize = ptSize * 10 + *cp - '0';
                    ++cp;
                }
                if (*cp == '.') {
                    double dec = 1.0;
                    ++cp;
                    while (*cp >= '0' && *cp <= '9') {
                        dec = dec * 10.0;
                        ptSize = ptSize + (*cp - '0') / dec;
                        ++cp;
                    }
                }
                goto skip_to_slash;
            }

            /* if the code is "B" or "I", we skip putting it in varString */
            while (1) {
                if (*cp == 'B') {
                    reqBold = true;
                    ++cp;
                    continue;
                }
                if (*cp == 'I') {
                    reqItal = true;
                    ++cp;
                    continue;
                }
                break;
            }

        skip_to_slash:
            while (*cp && *cp != '/')
                ++cp;
            if (*cp == '/')
                ++cp;
        }
        strcpy(variant, varString.c_str());

        std::map<std::string,Font*>::iterator i;
        if (reqItal) {
            Font* bestMatch = font;
            if (font->slant < parent->maxSlant)
                // try for a face with more slant
                bestMatch = bestMatchFromFamily(parent, font->weight, font->width, parent->maxSlant);

            if (bestMatch == font && font->slant > parent->minSlant)
                // maybe the slant is negated, or maybe this was something like "Times-Italic/I"
                bestMatch = bestMatchFromFamily(parent, font->weight, font->width, parent->minSlant);

            if (parent->minWeight == parent->maxWeight && bestMatch->isBold != font->isBold) {
                // try again using the bold flag, as we can't trust weight values
                Font* newBest = NULL;
                for (i = parent->styles->begin(); i != parent->styles->end(); ++i) {
                    if (i->second->isBold == font->isBold) {
                        if (newBest == NULL && i->second->isItalic != font->isItalic) {
                            newBest = i->second;
                            break;
                        }
                    }
                }
                if (newBest != NULL)
                    bestMatch = newBest;
            }

            if (bestMatch == font) {
                // maybe slant values weren't present; try the style bits as a fallback
                bestMatch = NULL;
                for (i = parent->styles->begin(); i != parent->styles->end(); ++i) {
                    if (i->second->isItalic == !font->isItalic) {
                        if (parent->minWeight != parent->maxWeight) {
                            // weight info was available, so try to match that
                            if (bestMatch == NULL || weightAndWidthDiff(i->second, font) < weightAndWidthDiff(bestMatch, font))
                                bestMatch = i->second;
                        } else {
                            // no weight info, so try matching style bits
                            if (bestMatch == NULL && i->second->isBold == font->isBold) {
                                bestMatch = i->second;
                                break;  // found a match, no need to look further as we can't distinguish!
                            }
                        }
                    }
                }
            }
            if (bestMatch != NULL)
                font = bestMatch;
        }

        if (reqBold) {
            // try for more boldness, with the same width and slant
            Font* bestMatch = font;
            if (font->weight < parent->maxWeight) {
                // try to increase weight by 1/2 x (max - min), rounding up
                bestMatch = bestMatchFromFamily(parent,
                    font->weight + (parent->maxWeight - parent->minWeight) / 2 + 1,
                    font->width, font->slant);
                if (parent->minSlant == parent->maxSlant) {
                    // double-check the italic flag, as we can't trust slant values
                    Font* newBest = NULL;
                    for (i = parent->styles->begin(); i != parent->styles->end(); ++i) {
                        if (i->second->isItalic == font->isItalic) {
                            if (newBest == NULL || weightAndWidthDiff(i->second, bestMatch) < weightAndWidthDiff(newBest, bestMatch))
                                newBest = i->second;
                        }
                    }
                    if (newBest != NULL)
                        bestMatch = newBest;
                }
            }
            if (bestMatch == font && !font->isBold) {
                for (i = parent->styles->begin(); i != parent->styles->end(); ++i) {
                    if (i->second->isItalic == font->isItalic && i->second->isBold) {
                        bestMatch = i->second;
                        break;
                    }
                }
            }
            font = bestMatch;
        }
    }

    // if there's optical size info, try to apply it
    if (ptSize < 0.0)
        ptSize = dsize / 10.0;
    if (font != NULL && font->opSizeInfo.subFamilyID != 0 && ptSize > 0.0) {
        ptSize = ptSize * 10.0; // convert to decipoints for comparison with the opSize values
        double bestMismatch = my_fmax(font->opSizeInfo.minSize - ptSize, ptSize - font->opSizeInfo.maxSize);
        if (bestMismatch > 0.0) {
            Font* bestMatch = font;
            for (std::map<std::string,Font*>::iterator i = parent->styles->begin(); i != parent->styles->end(); ++i) {
                if (i->second->opSizeInfo.subFamilyID != font->opSizeInfo.subFamilyID)
                    continue;
                double mismatch = my_fmax(i->second->opSizeInfo.minSize - ptSize, ptSize - i->second->opSizeInfo.maxSize);
                if (mismatch < bestMismatch) {
                    bestMatch = i->second;
                    bestMismatch = mismatch;
                }
                if (bestMismatch <= 0.0)
                    break;
            }
            font = bestMatch;
        }
    }

    if (font != NULL && font->opSizeInfo.designSize != 0)
        loadedfontdesignsize = (font->opSizeInfo.designSize << 16L) / 10;

    if (gettracingfontsstate() > 0) {
        begindiagnostic();
        zprintnl(' ');
        printcstring("-> ");
        printcstring(getPlatformFontDesc(font->fontRef).c_str());
        zenddiagnostic(0);
    }

    return font->fontRef;
}

const char*
XeTeXFontMgr::getFullName(PlatformFontRef font) const
{
    std::map<PlatformFontRef,Font*>::const_iterator i = m_platformRefToFont.find(font);
    if (i == m_platformRefToFont.end())
        die("internal error %d in XeTeXFontMgr", 2);
    if (i->second->m_fullName != NULL)
        return i->second->m_fullName->c_str();
    else
        return i->second->m_psName->c_str();
}

int
XeTeXFontMgr::weightAndWidthDiff(const Font* a, const Font* b) const
{
    if (a->weight == 0 && a->width == 0) {
        // assume there was no OS/2 info
        if (a->isBold == b->isBold)
            return 0;
        else
            return 10000;
    }

    int widDiff = labs(a->width - b->width);
    if (widDiff < 10)
        widDiff *= 50;

    return labs(a->weight - b->weight) + widDiff;
}

int
XeTeXFontMgr::styleDiff(const Font* a, int wt, int wd, int slant) const
{
    int widDiff = labs(a->width - wd);
    if (widDiff < 10)
        widDiff *= 200;

    return labs(labs(a->slant) - labs(slant)) * 2 + labs(a->weight - wt) + widDiff;
}

XeTeXFontMgr::Font*
XeTeXFontMgr::bestMatchFromFamily(const Family* fam, int wt, int wd, int slant) const
{
    Font* bestMatch = NULL;
    for (std::map<std::string,Font*>::iterator s = fam->styles->begin(); s != fam->styles->end(); ++s)
        if (bestMatch == NULL || styleDiff(s->second, wt, wd, slant) < styleDiff(bestMatch, wt, wd, slant))
            bestMatch = s->second;
    return bestMatch;
}

const XeTeXFontMgr::OpSizeRec*
XeTeXFontMgr::getOpSize(XeTeXFont font)
{
    hb_font_t* hbFont = ((XeTeXFontInst*)font)->getHbFont();
    if (hbFont != NULL) {
        hb_face_t* face = hb_font_get_face(hbFont);
        OpSizeRec* pSizeRec = (OpSizeRec*) xmalloc(sizeof(OpSizeRec));

        bool ok = hb_ot_layout_get_size_params(face,
                &pSizeRec->designSize,
                &pSizeRec->subFamilyID,
                &pSizeRec->nameCode,
                &pSizeRec->minSize,
                &pSizeRec->maxSize);

        if (ok)
            return pSizeRec;

        free(pSizeRec);
        return NULL;
    }

    return NULL;
}

double
XeTeXFontMgr::getDesignSize(XeTeXFont font)
{
    const OpSizeRec* pSizeRec = getOpSize(font);
    if (pSizeRec != NULL)
        return pSizeRec->designSize / 10.0;
    else
        return 10.0;
}

void
XeTeXFontMgr::getOpSizeRecAndStyleFlags(Font* theFont)
{
    XeTeXFont font = createFont(theFont->fontRef, 655360);
    XeTeXFontInst* fontInst = (XeTeXFontInst*) font;
    if (font != 0) {
        const OpSizeRec* pSizeRec = getOpSize(font);
        if (pSizeRec != NULL) {
            theFont->opSizeInfo.designSize = pSizeRec->designSize;
            if (pSizeRec->subFamilyID == 0
                && pSizeRec->nameCode == 0
                && pSizeRec->minSize == 0
                && pSizeRec->maxSize == 0)
                goto done_size; // feature is valid, but no 'size' range
            theFont->opSizeInfo.subFamilyID = pSizeRec->subFamilyID;
            theFont->opSizeInfo.nameCode = pSizeRec->nameCode;
            theFont->opSizeInfo.minSize = pSizeRec->minSize;
            theFont->opSizeInfo.maxSize = pSizeRec->maxSize;
        }
    done_size:

        const TT_OS2* os2Table = (TT_OS2*) fontInst->getFontTable(ft_sfnt_os2);
        if (os2Table != NULL) {
            theFont->weight = os2Table->usWeightClass;
            theFont->width = os2Table->usWidthClass;
            uint16_t sel = os2Table->fsSelection;
            theFont->isReg = (sel & (1 << 6)) != 0;
            theFont->isBold = (sel & (1 << 5)) != 0;
            theFont->isItalic = (sel & (1 << 0)) != 0;
        }

        const TT_Header* headTable = (TT_Header*) fontInst->getFontTable(ft_sfnt_head);
        if (headTable != NULL) {
            uint16_t ms = headTable->Mac_Style;
            if ((ms & (1 << 0)) != 0)
                theFont->isBold = true;
            if ((ms & (1 << 1)) != 0)
                theFont->isItalic = true;
        }

        const TT_Postscript* postTable = (const TT_Postscript*) fontInst->getFontTable(ft_sfnt_post);
        if (postTable != NULL) {
            theFont->slant = (int)(1000 * (tan(Fix2D(-postTable->italicAngle) * M_PI / 180.0)));
        }
        deleteFont(font);
    }
}

// append a name but only if it's not already in the list
void
XeTeXFontMgr::appendToList(std::list<std::string>* list, const char* str)
{
    for (std::list<std::string>::const_iterator i = list->begin(); i != list->end(); ++i)
        if (*i == str)
            return;
    list->push_back(str);
}

// prepend a name, removing it from later in the list if present
void
XeTeXFontMgr::prependToList(std::list<std::string>* list, const char* str)
{
    for (std::list<std::string>::iterator i = list->begin(); i != list->end(); ++i)
        if (*i == str) {
            list->erase(i);
            break;
        }
    list->push_front(str);
}

void
XeTeXFontMgr::addToMaps(PlatformFontRef platformFont, const NameCollection* names)
{
    if (m_platformRefToFont.find(platformFont) != m_platformRefToFont.end())
        return; // this font has already been cached

    if (names->m_psName.length() == 0)
        return; // can't use a font that lacks a PostScript name

    if (m_psNameToFont.find(names->m_psName) != m_psNameToFont.end())
        return; // duplicates an earlier PS name, so skip

    Font* thisFont = new Font(platformFont);
    thisFont->m_psName = new std::string(names->m_psName);
    getOpSizeRecAndStyleFlags(thisFont);

    m_psNameToFont[names->m_psName] = thisFont;
    m_platformRefToFont[platformFont] = thisFont;

    if (names->m_fullNames.size() > 0)
        thisFont->m_fullName = new std::string(*(names->m_fullNames.begin()));

    if (names->m_familyNames.size() > 0)
        thisFont->m_familyName = new std::string(*(names->m_familyNames.begin()));
    else
        thisFont->m_familyName = new std::string(names->m_psName);

    if (names->m_styleNames.size() > 0)
        thisFont->m_styleName = new std::string(*(names->m_styleNames.begin()));
    else
        thisFont->m_styleName = new std::string;

    std::list<std::string>::const_iterator i;
    for (i = names->m_familyNames.begin(); i != names->m_familyNames.end(); ++i) {
        std::map<std::string,Family*>::iterator iFam = m_nameToFamily.find(*i);
        Family* family;
        if (iFam == m_nameToFamily.end()) {
            family = new Family;
            m_nameToFamily[*i] = family;
            family->minWeight = thisFont->weight;
            family->maxWeight = thisFont->weight;
            family->minWidth = thisFont->width;
            family->maxWidth = thisFont->width;
            family->minSlant = thisFont->slant;
            family->maxSlant = thisFont->slant;
        } else {
            family = iFam->second;
            if (thisFont->weight < family->minWeight)
                family->minWeight = thisFont->weight;
            if (thisFont->weight > family->maxWeight)
                family->maxWeight = thisFont->weight;
            if (thisFont->width < family->minWidth)
                family->minWidth = thisFont->width;
            if (thisFont->width > family->maxWidth)
                family->maxWidth = thisFont->width;
            if (thisFont->slant < family->minSlant)
                family->minSlant = thisFont->slant;
            if (thisFont->slant > family->maxSlant)
                family->maxSlant = thisFont->slant;
        }

        if (thisFont->parent == NULL)
            thisFont->parent = family;

        // ensure all style names in the family point to thisFont
        for (std::list<std::string>::const_iterator j = names->m_styleNames.begin(); j != names->m_styleNames.end(); ++j) {
            std::map<std::string,Font*>::iterator iFont = family->styles->find(*j);
            if (iFont == family->styles->end())
                (*family->styles)[*j] = thisFont;
/*
            else if (iFont->second != thisFont)
                fprintf(stderr, "# Font name warning: ambiguous Style \"%s\" in Family \"%s\" (PSNames \"%s\" and \"%s\")\n",
                            j->c_str(), i->c_str(), iFont->second->m_psName->c_str(), thisFont->m_psName->c_str());
*/
        }
    }

    for (i = names->m_fullNames.begin(); i != names->m_fullNames.end(); ++i) {
        std::map<std::string,Font*>::iterator iFont = m_nameToFont.find(*i);
        if (iFont == m_nameToFont.end())
            m_nameToFont[*i] = thisFont;
/*
        else if (iFont->second != thisFont)
            fprintf(stderr, "# Font name warning: ambiguous FullName \"%s\" (PSNames \"%s\" and \"%s\")\n",
                        i->c_str(), iFont->second->m_psName->c_str(), thisFont->m_psName->c_str());
*/
    }
}

void
XeTeXFontMgr::die(const char*s, int i) const
{
    fprintf(stderr, s, i);
    fprintf(stderr, " - exiting\n");
    exit(3);
}

void
XeTeXFontMgr::terminate()
{
}