/* * Copyright 2006 The Android Open Source Project * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file.
*/
// define this in your Makefile or .gyp to enforce AA requests // which GDI ignores at small sizes. This flag guarantees AA // for rotated text, regardless of GDI's notions. //#define SK_ENFORCE_ROTATED_TEXT_AA_ON_WINDOWS
staticbool bothZero(SkScalar a, SkScalar b) { return 0 == a && 0 == b;
}
// returns false if there is any non-90-rotation or skew staticbool isAxisAligned(const SkScalerContextRec& rec) { return 0 == rec.fPreSkewX &&
(bothZero(rec.fPost2x2[0][1], rec.fPost2x2[1][0]) ||
bothZero(rec.fPost2x2[0][0], rec.fPost2x2[1][1]));
}
staticbool needToRenderWithSkia(const SkScalerContextRec& rec) { #ifdef SK_ENFORCE_ROTATED_TEXT_AA_ON_WINDOWS // What we really want to catch is when GDI will ignore the AA request and give // us BW instead. Smallish rotated text is one heuristic, so this code is just // an approximation. We shouldn't need to do this for larger sizes, but at those // sizes, the quality difference gets less and less between our general // scanconverter and GDI's. if (SkMask::kA8_Format == rec.fMaskFormat && !isAxisAligned(rec)) { returntrue;
} #endif return rec.getHinting() == SkFontHinting::kNone || rec.getHinting() == SkFontHinting::kSlight;
}
if (!(textMetric.tmPitchAndFamily & TMPF_VECTOR)) { return textMetric.tmLastChar;
}
// The 'maxp' table stores the number of glyphs at offset 4, in 2 bytes.
uint16_t glyphs; if (GDI_ERROR != GetFontData(hdc, SkOTTableMaximumProfile::TAG, 4, &glyphs, sizeof(glyphs))) { return SkEndian_SwapBE16(glyphs);
}
// Binary search for glyph count. staticconst MAT2 mat2 = {{0, 1}, {0, 0}, {0, 0}, {0, 1}};
int32_t max = UINT16_MAX + 1;
int32_t min = 0;
GLYPHMETRICS gm; while (min < max) {
int32_t mid = min + ((max - min) / 2); if (GetGlyphOutlineW(hdc, mid, GGO_METRICS | GGO_GLYPH_INDEX, &gm, 0,
nullptr, &mat2) == GDI_ERROR) {
max = mid;
} else {
min = mid + 1;
}
}
SkASSERT(min == max); return min;
}
// The fixed pitch bit is set if the font is *not* fixed pitch.
this->setIsFixedPitch((textMetric.tmPitchAndFamily & TMPF_FIXED_PITCH) == 0);
this->setFontStyle(SkFontStyle(textMetric.tmWeight, style.width(), style.slant()));
// Used a logfont on a memory context, should never get a device font. // Therefore all TMPF_DEVICE will be PostScript (cubic) fonts. // If the font has cubic outlines, it will not be rendered with ClearType.
fCanBeLCD = !((textMetric.tmPitchAndFamily & TMPF_VECTOR) &&
(textMetric.tmPitchAndFamily & TMPF_DEVICE));
}
/** * This is public. It first searches the cache, and if a match is not found, * it creates a new face.
*/
sk_sp<SkTypeface> SkCreateTypefaceFromLOGFONT(const LOGFONT& origLF) {
LOGFONT lf = origLF;
make_canonical(&lf);
sk_sp<SkTypeface> face = SkTypefaceCache::FindByProcAndRef(FindByLogFont, &lf); if (!face) {
face = LogFontTypeface::Make(lf);
SkTypefaceCache::Add(face);
} return face;
}
/*** * This guy is public.
*/
SkTypeface* SkCreateTypefaceFromDWriteFont(IDWriteFactory* aFactory,
IDWriteFontFace* aFontFace,
SkFontStyle aStyle, int aRenderingMode, float aGamma, float aContrast, float aClearTypeLevel)
{ return DWriteFontTypeface::Create(aFactory, aFontFace, aStyle,
(DWRITE_RENDERING_MODE)aRenderingMode,
aGamma, aContrast, aClearTypeLevel);
}
/** * The created SkTypeface takes ownership of fontMemResource.
*/
sk_sp<SkTypeface> SkCreateFontMemResourceTypefaceFromLOGFONT(const LOGFONT& origLF, HANDLE fontMemResource) {
LOGFONT lf = origLF;
make_canonical(&lf); // We'll never get a cache hit, so no point in putting this in SkTypefaceCache. return FontMemResourceTypeface::Make(lf, fontMemResource);
}
/** * This is public
*/ void SkLOGFONTFromTypeface(const SkTypeface* face, LOGFONT* lf) { if (nullptr == face) {
*lf = get_default_font();
} else {
*lf = static_cast<const LogFontTypeface*>(face)->fLogFont;
}
}
// Construct Glyph to Unicode table. // Unicode code points that require conjugate pairs in utf16 are not // supported. // TODO(arthurhsu): Add support for conjugate pairs. It looks like that may // require parsing the TTF cmap table (platform 4, encoding 12) directly instead // of calling GetFontUnicodeRange(). staticvoid populate_glyph_to_unicode(HDC fontHdc, constunsigned glyphCount,
SkUnichar* glyphToUnicode) {
sk_bzero(glyphToUnicode, sizeof(SkUnichar) * glyphCount);
DWORD glyphSetBufferSize = GetFontUnicodeRanges(fontHdc, nullptr); if (!glyphSetBufferSize) { return;
}
for (DWORD i = 0; i < glyphSet->cRanges; ++i) { // There is no guarantee that within a Unicode range, the corresponding // glyph id in a font file are continuous. So, even if we have ranges, // we can't just use the first and last entry of the range to compute // result. We need to enumerate them one by one. int count = glyphSet->ranges[i].cGlyphs;
AutoTArray<WCHAR> chars(count + 1);
chars[count] = 0; // termintate string
AutoTArray<WORD> glyph(count); for (USHORT j = 0; j < count; ++j) {
chars[j] = glyphSet->ranges[i].wcLow + j;
}
GetGlyphIndicesW(fontHdc, chars.get(), count, glyph.get(),
GGI_MARK_NONEXISTING_GLYPHS); // If the glyph ID is valid, and the glyph is not mapped, then we will // fill in the char id into the vector. If the glyph is mapped already, // skip it. // TODO(arthurhsu): better improve this. e.g. Get all used char ids from // font cache, then generate this mapping table from there. It's // unlikely to have collisions since glyph reuse happens mostly for // different Unicode pages. for (USHORT j = 0; j < count; ++j) { if (glyph[j] != 0xFFFF && glyph[j] < glyphCount && glyphToUnicode[glyph[j]] == 0) {
glyphToUnicode[glyph[j]] = chars[j];
}
}
}
}
private:
HDC fDC{nullptr};
HFONT fSavefont{nullptr};
HBITMAP fBM{nullptr};
HFONT fFont{nullptr};
XFORM fXform{1, 0, 0, 1, 0, 0}; void* fBits{nullptr}; // points into fBM int fWidth{0}; int fHeight{0}; bool fIsBW{false};
};
void* HDCOffscreen::draw(const SkGlyph& glyph, bool isBW, size_t* srcRBPtr) { // Can we share the scalercontext's fDDC, so we don't need to create // a separate fDC here? if (nullptr == fDC) {
fDC = CreateCompatibleDC(0); if (nullptr == fDC) { return nullptr;
}
SetGraphicsMode(fDC, GM_ADVANCED);
SetBkMode(fDC, TRANSPARENT);
SetTextAlign(fDC, TA_LEFT | TA_BASELINE);
fSavefont = (HFONT)SelectObject(fDC, fFont);
HDCOffscreen fOffscreen; /** fGsA is the non-rotational part of total matrix without the text height scale. * Used to find the magnitude of advances.
*/
MAT2 fGsA; /** The total matrix without the textSize. */
MAT2 fMat22; /** Scales font to EM size. */
MAT2 fHighResMat22;
HDC fDDC;
HFONT fSavefont;
HFONT fFont;
SCRIPT_CACHE fSC;
/** The total matrix which also removes EM scale. */
SkMatrix fHiResMatrix; /** fG_inv is the inverse of the rotational part of the total matrix. * Used to set the direction of advances.
*/
SkMatrix fG_inv; enum Type {
kTrueType_Type, kBitmap_Type, kLine_Type
} fType;
TEXTMETRIC fTM;
};
// When GDI hinting, remove the entire Y scale from sA and GsA. (Prevents 'linear' metrics.) // When not hinting, remove only the integer Y scale from sA and GsA. (Applied by GDI.)
SkScalerContextRec::PreMatrixScale scaleConstraints =
(fRec.getHinting() == SkFontHinting::kNone || fRec.getHinting() == SkFontHinting::kSlight)
? SkScalerContextRec::PreMatrixScale::kVerticalInteger
: SkScalerContextRec::PreMatrixScale::kVertical;
SkVector scale;
SkMatrix sA;
SkMatrix GsA;
SkMatrix A;
fRec.computeMatrices(scaleConstraints, &scale, &sA, &GsA, &fG_inv, &A);
fGsA.eM11 = SkScalarToFIXED(GsA.get(SkMatrix::kMScaleX));
fGsA.eM12 = SkScalarToFIXED(-GsA.get(SkMatrix::kMSkewY)); // This should be ~0.
fGsA.eM21 = SkScalarToFIXED(-GsA.get(SkMatrix::kMSkewX));
fGsA.eM22 = SkScalarToFIXED(GsA.get(SkMatrix::kMScaleY));
// When not hinting, scale was computed with kVerticalInteger, so is already an integer. // The sA and GsA transforms will be used to create 'linear' metrics.
// When hinting, scale was computed with kVertical, stating that our port can handle // non-integer scales. This is done so that sA and GsA are computed without any 'residual' // scale in them, preventing 'linear' metrics. However, GDI cannot actually handle non-integer // scales so we need to round in this case. This is fine, since all of the scale has been // removed from sA and GsA, so GDI will be handling the scale completely.
SkScalar gdiTextSize = SkScalarRoundToScalar(scale.fY);
// GDI will not accept a size of zero, so round the range [0, 1] to 1. // If the size was non-zero, the scale factors will also be non-zero and 1px tall text is drawn. // If the size actually was zero, the scale factors will also be zero, so GDI will draw nothing. if (gdiTextSize == 0) {
gdiTextSize = SK_Scalar1;
}
if (0 == GetTextMetrics(fDDC, &fTM)) {
call_ensure_accessible(lf); if (0 == GetTextMetrics(fDDC, &fTM)) {
fTM.tmPitchAndFamily = TMPF_TRUETYPE;
}
}
XFORM xform; if (fTM.tmPitchAndFamily & TMPF_VECTOR) { // Used a logfont on a memory context, should never get a device font. // Therefore all TMPF_DEVICE will be PostScript fonts.
// If TMPF_VECTOR is set, one of TMPF_TRUETYPE or TMPF_DEVICE means that // we have an outline font. Otherwise we have a vector FON, which is // scalable, but not an outline font. // This was determined by testing with Type1 PFM/PFB and // OpenTypeCFF OTF, as well as looking at Wine bugs and sources. if (fTM.tmPitchAndFamily & (TMPF_TRUETYPE | TMPF_DEVICE)) { // Truetype or PostScript.
fType = SkScalerContext_GDI::kTrueType_Type;
} else { // Stroked FON.
fType = SkScalerContext_GDI::kLine_Type;
}
// fPost2x2 is column-major, left handed (y down). // XFORM 2x2 is row-major, left handed (y down).
xform.eM11 = SkScalarToFloat(sA.get(SkMatrix::kMScaleX));
xform.eM12 = SkScalarToFloat(sA.get(SkMatrix::kMSkewY));
xform.eM21 = SkScalarToFloat(sA.get(SkMatrix::kMSkewX));
xform.eM22 = SkScalarToFloat(sA.get(SkMatrix::kMScaleY));
xform.eDx = 0;
xform.eDy = 0;
// Bitmap FON cannot underhang, but vector FON may. // There appears no means of determining underhang of vector FON. int left = 0; int top = -fTM.tmAscent;
// These do not have an outline path at all.
mx.neverRequestPath = true; return mx;
}
UINT glyphId = glyph.getGlyphID();
GLYPHMETRICS gm;
sk_bzero(&gm, sizeof(gm));
DWORD status = GetGlyphOutlineW(fDDC, glyphId, GGO_METRICS | GGO_GLYPH_INDEX, &gm, 0, nullptr, &fMat22); if (GDI_ERROR == status) {
LogFontTypeface::EnsureAccessible(this->getTypeface());
status = GetGlyphOutlineW(fDDC, glyphId, GGO_METRICS | GGO_GLYPH_INDEX, &gm, 0, nullptr, &fMat22); if (GDI_ERROR == status) { return mx;
}
}
bool empty = false; // The black box is either the embedded bitmap size or the outline extent. // It is 1x1 if nothing is to be drawn, but will also be 1x1 if something very small // is to be drawn, like a '.'. We need to outset '.' but do not wish to outset ' '. if (1 == gm.gmBlackBoxX && 1 == gm.gmBlackBoxY) { // If GetGlyphOutline with GGO_NATIVE returns 0, we know there was no outline.
DWORD bufferSize = GetGlyphOutlineW(fDDC, glyphId, GGO_NATIVE | GGO_GLYPH_INDEX, &gm, 0, nullptr, &fMat22);
empty = (0 == bufferSize);
}
if (!empty) { int y = -gm.gmptGlyphOrigin.y; int x = gm.gmptGlyphOrigin.x; // Outset, since the image may bleed out of the black box. // For embedded bitmaps the black box should be exact. // For outlines we need to outset by 1 in all directions for bleed. // For ClearType we need to outset by 2 for bleed.
mx.bounds = SkRect::MakeXYWH(x, y, gm.gmBlackBoxX, gm.gmBlackBoxY).makeOutset(2, 2);
} // TODO(benjaminwagner): What is the type of gm.gmCellInc[XY]?
mx.advance.fX = (float)((int)gm.gmCellIncX);
mx.advance.fY = (float)((int)gm.gmCellIncY);
staticvoid build_power_table(uint8_t table[], float ee) { for (int i = 0; i < 256; i++) { float x = i / 255.f;
x = std::pow(x, ee); int xx = SkScalarRoundToInt(x * 255);
table[i] = SkToU8(xx);
}
}
/** * This will invert the gamma applied by GDI (gray-scale antialiased), so we * can get linear values. * * GDI grayscale appears to use a hard-coded gamma of 2.3. * * GDI grayscale appears to draw using the black and white rasterizer at four * times the size and then downsamples to compute the coverage mask. As a * result there are only seventeen total grays. This lack of fidelity means * that shifting into other color spaces is imprecise.
*/ staticconst uint8_t* getInverseGammaTableGDI() { static SkOnce once; static uint8_t gTableGdi[256];
once([]{
build_power_table(gTableGdi, 2.3f);
}); return gTableGdi;
}
/** * This will invert the gamma applied by GDI ClearType, so we can get linear * values. * * GDI ClearType uses SPI_GETFONTSMOOTHINGCONTRAST / 1000 as the gamma value. * If this value is not specified, the default is a gamma of 1.4.
*/ staticconst uint8_t* getInverseGammaTableClearType() { static SkOnce once; static uint8_t gTableClearType[256];
once([]{
UINT level = 0; if (!SystemParametersInfo(SPI_GETFONTSMOOTHINGCONTRAST, 0, &level, 0) || !level) { // can't get the data, so use a default
level = 1400;
}
build_power_table(gTableClearType, level / 1000.0f);
}); return gTableClearType;
}
#include"include/private/SkColorData.h"
//Cannot assume that the input rgb is gray due to possible setting of kGenA8FromLCD_Flag. template<bool APPLY_PREBLEND> staticinline uint8_t rgb_to_a8(SkGdiRGB rgb, const uint8_t* table8) {
U8CPU r = (rgb >> 16) & 0xFF;
U8CPU g = (rgb >> 8) & 0xFF;
U8CPU b = (rgb >> 0) & 0xFF; return sk_apply_lut_if<APPLY_PREBLEND>(SkComputeLuminance(r, g, b), table8);
}
template<bool APPLY_PREBLEND> staticinline uint16_t rgb_to_lcd16(SkGdiRGB rgb, const uint8_t* tableR, const uint8_t* tableG, const uint8_t* tableB) {
U8CPU r = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 16) & 0xFF, tableR);
U8CPU g = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 8) & 0xFF, tableG);
U8CPU b = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 0) & 0xFF, tableB); if constexpr (kSkShowTextBlitCoverage) {
r = std::max(r, 10u);
g = std::max(g, 10u);
b = std::max(b, 10u);
} return SkPack888ToRGB16(r, g, b);
}
if (!isBW) { const uint8_t* table; //The offscreen contains a GDI blit if isAA and kGenA8FromLCD_Flag is not set. //Otherwise the offscreen contains a ClearType blit. if (isAA && !(fRec.fFlags & SkScalerContext::kGenA8FromLCD_Flag)) {
table = getInverseGammaTableGDI();
} else {
table = getInverseGammaTableClearType();
} //Note that the following cannot really be integrated into the //pre-blend, since we may not be applying the pre-blend; when we aren't //applying the pre-blend it means that a filter wants linear anyway. //Other code may also be applying the pre-blend, so we'd need another //one with this and one without.
SkGdiRGB* addr = (SkGdiRGB*)bits; for (int y = 0; y < glyph.height(); ++y) { for (int x = 0; x < glyph.width(); ++x) { int r = (addr[x] >> 16) & 0xFF; int g = (addr[x] >> 8) & 0xFF; int b = (addr[x] >> 0) & 0xFF;
addr[x] = (table[r] << 16) | (table[g] << 8) | table[b];
}
addr = SkTAddOffset<SkGdiRGB>(addr, srcRB);
}
}
size_t dstRB = glyph.rowBytes(); if (isBW) { const uint8_t* src = (const uint8_t*)bits;
uint8_t* dst = (uint8_t*)((char*)imageBuffer + (glyph.height() - 1) * dstRB); for (int y = 0; y < glyph.height(); y++) {
memcpy(dst, src, dstRB);
src += srcRB;
dst -= dstRB;
} if constexpr (kSkShowTextBlitCoverage) { if (glyph.width() > 0 && glyph.height() > 0) { int bitCount = glyph.width() & 7;
uint8_t* first = (uint8_t*)imageBuffer;
uint8_t* last = first + glyph.height() * dstRB - 1;
*first |= 1 << 7;
*last |= bitCount == 0 ? 1 : 1 << (8 - bitCount);
}
}
} elseif (isAA) { // since the caller may require A8 for maskfilters, we can't check for BW // ... until we have the caller tell us that explicitly const SkGdiRGB* src = (const SkGdiRGB*)bits; if (fPreBlend.isApplicable()) {
RGBToA8<true>(src, srcRB, glyph, imageBuffer, fPreBlend.fG);
} else {
RGBToA8<false>(src, srcRB, glyph, imageBuffer, fPreBlend.fG);
}
} else { // LCD16 const SkGdiRGB* src = (const SkGdiRGB*)bits;
SkASSERT(SkMask::kLCD16_Format == glyph.maskFormat()); if (fPreBlend.isApplicable()) {
RGBToLcd16<true>(src, srcRB, glyph, imageBuffer,
fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
} else {
RGBToLcd16<false>(src, srcRB, glyph, imageBuffer,
fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
}
}
}
WORD currentCurveType() { return fPointIter.fCurveType;
}
private: /** Iterates over all of the polygon headers in a glyphbuf. */ class GDIPolygonHeaderIter { public:
GDIPolygonHeaderIter(const uint8_t* glyphbuf, DWORD total_size)
: fCurPolygon(reinterpret_cast<const TTPOLYGONHEADER*>(glyphbuf))
, fEndPolygon(SkTAddOffset<const TTPOLYGONHEADER>(glyphbuf, total_size))
{ }
/** Iterates over all of the polygon curves in a polygon header. */ class GDIPolygonCurveIter { public:
GDIPolygonCurveIter() : fCurCurve(nullptr), fEndCurve(nullptr) { }
/** Iterates over all of the polygon points in a polygon curve. */ class GDIPolygonCurvePointIter { public:
GDIPolygonCurvePointIter() : fCurveType(0), fCurPoint(nullptr), fEndPoint(nullptr) { }
/** It is possible for the hinted and unhinted versions of the same path to have * a different number of points due to GDI's handling of flipped points. * If this is detected, this will return false.
*/ bool process(const uint8_t* glyphbuf, DWORD total_size, GDIGlyphbufferPointIter hintedYs);
};
while (cur_poly < end_poly) { const TTPOLYCURVE* pc = (const TTPOLYCURVE*)cur_poly; const POINTFX* apfx = pc->apfx; const WORD cpfx = pc->cpfx;
if (pc->wType == TT_PRIM_LINE) { for (uint16_t i = 0; i < cpfx; i++) {
POINTFX pnt_b = apfx[i]; if (this->currentIsNot(pnt_b)) {
this->goingTo(pnt_b);
fPath->lineTo( SkFIXEDToScalar(pnt_b.x),
-SkFIXEDToScalar(pnt_b.y));
}
}
}
if (pc->wType == TT_PRIM_QSPLINE) { for (uint16_t u = 0; u < cpfx - 1; u++) { // Walk through points in spline
POINTFX pnt_b = apfx[u]; // B is always the current point
POINTFX pnt_c = apfx[u+1];
if (u < cpfx - 2) { // If not on last spline, compute C
pnt_c.x = SkFixedToFIXED(SkFixedAve(SkFIXEDToFixed(pnt_b.x),
SkFIXEDToFixed(pnt_c.x)));
pnt_c.y = SkFixedToFIXED(SkFixedAve(SkFIXEDToFixed(pnt_b.y),
SkFIXEDToFixed(pnt_c.y)));
}
while (cur_poly < end_poly) { const TTPOLYCURVE* pc = (const TTPOLYCURVE*)cur_poly; const POINTFX* apfx = pc->apfx; const WORD cpfx = pc->cpfx;
if (pc->wType == TT_PRIM_LINE) { for (uint16_t i = 0; i < cpfx; i++) {
move_next_expected_hinted_point(hintedYs, hintedPoint);
POINTFX pnt_b = {apfx[i].x, hintedPoint->y}; if (this->currentIsNot(pnt_b)) {
this->goingTo(pnt_b);
fPath->lineTo( SkFIXEDToScalar(pnt_b.x),
-SkFIXEDToScalar(pnt_b.y));
}
}
}
if (pc->wType == TT_PRIM_QSPLINE) {
POINTFX currentPoint = apfx[0];
move_next_expected_hinted_point(hintedYs, hintedPoint); // only take the hinted y if it wasn't flipped if (hintedYs.currentCurveType() == TT_PRIM_QSPLINE) {
currentPoint.y = hintedPoint->y;
} for (uint16_t u = 0; u < cpfx - 1; u++) { // Walk through points in spline
POINTFX pnt_b = currentPoint;//pc->apfx[u]; // B is always the current point
POINTFX pnt_c = apfx[u+1];
move_next_expected_hinted_point(hintedYs, hintedPoint); // only take the hinted y if it wasn't flipped if (hintedYs.currentCurveType() == TT_PRIM_QSPLINE) {
pnt_c.y = hintedPoint->y;
}
currentPoint.x = pnt_c.x;
currentPoint.y = pnt_c.y;
if (u < cpfx - 2) { // If not on last spline, compute C
pnt_c.x = SkFixedToFIXED(SkFixedAve(SkFIXEDToFixed(pnt_b.x),
SkFIXEDToFixed(pnt_c.x)));
pnt_c.y = SkFixedToFIXED(SkFixedAve(SkFIXEDToFixed(pnt_b.y),
SkFIXEDToFixed(pnt_c.y)));
}
DWORD total_size = GetGlyphOutlineW(fDDC, glyph, flags, &gm, BUFFERSIZE, glyphbuf->get(), &fMat22); // Sometimes GetGlyphOutlineW returns a number larger than BUFFERSIZE even if BUFFERSIZE > 0. // It has been verified that this does not involve a buffer overrun. if (GDI_ERROR == total_size || total_size > BUFFERSIZE) { // GDI_ERROR because the BUFFERSIZE was too small, or because the data was not accessible. // When the data is not accessable GetGlyphOutlineW fails rather quickly, // so just try to get the size. If that fails then ensure the data is accessible.
total_size = GetGlyphOutlineW(fDDC, glyph, flags, &gm, 0, nullptr, &fMat22); if (GDI_ERROR == total_size) {
LogFontTypeface::EnsureAccessible(this->getTypeface());
total_size = GetGlyphOutlineW(fDDC, glyph, flags, &gm, 0, nullptr, &fMat22); if (GDI_ERROR == total_size) { // GetGlyphOutlineW is known to fail for some characters, such as spaces. // In these cases, just return that the glyph does not have a shape. return 0;
}
}
glyphbuf->reset(total_size);
DWORD ret = GetGlyphOutlineW(fDDC, glyph, flags, &gm, total_size, glyphbuf->get(), &fMat22); if (GDI_ERROR == ret) {
LogFontTypeface::EnsureAccessible(this->getTypeface());
ret = GetGlyphOutlineW(fDDC, glyph, flags, &gm, total_size, glyphbuf->get(), &fMat22); if (GDI_ERROR == ret) {
SkASSERT(false); return 0;
}
}
} return total_size;
}
// Out of all the fonts on a typical Windows box, // 25% of glyphs require more than 2KB. // 1% of glyphs require more than 4KB. // 0.01% of glyphs require more than 8KB. // 8KB is less than 1% of the normal 1MB stack on Windows. // Note that some web fonts glyphs require more than 20KB. //static const DWORD BUFFERSIZE = (1 << 13);
//GDI only uses hinted outlines when axis aligned.
UINT format = GGO_NATIVE | GGO_GLYPH_INDEX; if (fRec.getHinting() == SkFontHinting::kNone || fRec.getHinting() == SkFontHinting::kSlight){
format |= GGO_UNHINTED;
}
AutoSTMalloc<BUFFERSIZE, uint8_t> glyphbuf(BUFFERSIZE);
DWORD total_size = getGDIGlyphPath(glyphID, format, &glyphbuf); if (0 == total_size) { returnfalse;
}
if (fRec.getHinting() != SkFontHinting::kSlight) {
SkGDIGeometrySink sink(path);
sink.process(glyphbuf, total_size);
} else {
AutoSTMalloc<BUFFERSIZE, uint8_t> hintedGlyphbuf(BUFFERSIZE); //GDI only uses hinted outlines when axis aligned.
DWORD hinted_total_size = getGDIGlyphPath(glyphID, GGO_NATIVE | GGO_GLYPH_INDEX,
&hintedGlyphbuf); if (0 == hinted_total_size) { returnfalse;
}
SkGDIGeometrySink sinkXBufYIter(path); if (!sinkXBufYIter.process(glyphbuf, total_size,
GDIGlyphbufferPointIter(hintedGlyphbuf, hinted_total_size)))
{ // Both path and sinkXBufYIter are in the state they were in at the time of failure.
path->reset();
SkGDIGeometrySink sink(path);
sink.process(glyphbuf, total_size);
}
} returntrue;
}
void LogFontTypeface::onGetFamilyName(SkString* familyName) const { // Get the actual name of the typeface. The logfont may not know this.
SkAutoHDC hdc(fLogFont);
dcfontname_to_skstring(hdc, fLogFont, familyName);
}
// The design HFONT must be destroyed after the HDC using HFONT_T = typename std::remove_pointer<HFONT>::type;
std::unique_ptr<HFONT_T, SkFunctionObject<DeleteObject>> designFont;
SkAutoHDC hdc(lf);
// To request design units, create a logical font whose height is specified // as unitsPerEm.
OUTLINETEXTMETRIC otm; unsignedint otmRet = GetOutlineTextMetrics(hdc, sizeof(otm), &otm); if (0 == otmRet) {
call_ensure_accessible(lf);
otmRet = GetOutlineTextMetrics(hdc, sizeof(otm), &otm);
} if (!otmRet || !GetTextFace(hdc, LF_FACESIZE, lf.lfFaceName)) { return info;
}
lf.lfHeight = -SkToS32(otm.otmEMSquare);
designFont.reset(CreateFontIndirect(&lf));
SelectObject(hdc, designFont.get()); if (!GetOutlineTextMetrics(hdc, sizeof(otm), &otm)) { return info;
}
glyphCount = calculateGlyphCount(hdc, fLogFont);
info.reset(new SkAdvancedTypefaceMetrics);
SkOTTableOS2_V4::Type fsType; if (sizeof(fsType) == this->getTableData(SkTEndian_SwapBE32(SkOTTableOS2::TAG),
offsetof(SkOTTableOS2_V4, fsType), sizeof(fsType),
&fsType)) {
SkOTUtils::SetAdvancedTypefaceFlags(fsType, info.get());
} else { // If bit 1 is set, the font may not be embedded in a document. // If bit 1 is clear, the font can be embedded. // If bit 2 is set, the embedding is read-only. if (otm.otmfsType & 0x1) {
info->fFlags |= SkAdvancedTypefaceMetrics::kNotEmbeddable_FontFlag;
}
}
// If this bit is clear the font is a fixed pitch font. if (!(otm.otmTextMetrics.tmPitchAndFamily & TMPF_FIXED_PITCH)) {
info->fStyle |= SkAdvancedTypefaceMetrics::kFixedPitch_Style;
} if (otm.otmTextMetrics.tmItalic) {
info->fStyle |= SkAdvancedTypefaceMetrics::kItalic_Style;
} if (otm.otmTextMetrics.tmPitchAndFamily & FF_ROMAN) {
info->fStyle |= SkAdvancedTypefaceMetrics::kSerif_Style;
} elseif (otm.otmTextMetrics.tmPitchAndFamily & FF_SCRIPT) {
info->fStyle |= SkAdvancedTypefaceMetrics::kScript_Style;
}
// The main italic angle of the font, in tenths of a degree counterclockwise // from vertical.
info->fItalicAngle = otm.otmItalicAngle / 10;
info->fAscent = SkToS16(otm.otmTextMetrics.tmAscent);
info->fDescent = SkToS16(-otm.otmTextMetrics.tmDescent); // TODO(ctguil): Use alternate cap height calculation. // MSDN says otmsCapEmHeight is not support but it is returning a value on // my Win7 box.
info->fCapHeight = otm.otmsCapEmHeight;
info->fBBox =
SkIRect::MakeLTRB(otm.otmrcFontBox.left, otm.otmrcFontBox.top,
otm.otmrcFontBox.right, otm.otmrcFontBox.bottom);
// Figure out a good guess for StemV - Min width of i, I, !, 1. // This probably isn't very good with an italic font.
min_width = SHRT_MAX;
info->fStemV = 0; for (size_t i = 0; i < std::size(stem_chars); i++) {
ABC abcWidths; if (GetCharABCWidths(hdc, stem_chars[i], stem_chars[i], &abcWidths)) {
int16_t width = abcWidths.abcB; if (width > 0 && width < min_width) {
min_width = width;
info->fStemV = min_width;
}
}
}
return info;
}
//Placeholder representation of a Base64 encoded GUID from create_unique_font_name. #define BASE64_GUID_ID "XXXXXXXXXXXXXXXXXXXXXXXX" //Length of GUID representation from create_id, including nullptr terminator. #define BASE64_GUID_ID_LEN std::size(BASE64_GUID_ID)
/** NameID 6 Postscript names cannot have the character '/'. It would be easier to hex encode the GUID, but that is 32 bytes, and many systems have issues with names longer than 28 bytes. The following need not be any standard base64 encoding. The encoded value is never decoded.
*/ staticconstchar postscript_safe_base64_encode[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz" "0123456789-_=";
/** Formats a GUID into Base64 and places it into buffer. buffer should have space for at least BASE64_GUID_ID_LEN characters. The string will always be null terminated. XXXXXXXXXXXXXXXXXXXXXXXX0
*/ staticvoid format_guid_b64(const GUID& guid, char* buffer, size_t bufferSize) {
SkASSERT(bufferSize >= BASE64_GUID_ID_LEN);
size_t written = SkBase64::Encode(&guid, sizeof(guid), buffer, postscript_safe_base64_encode);
SkASSERT(written < LF_FACESIZE);
buffer[written] = '\0';
}
/** Creates a Base64 encoded GUID and places it into buffer. buffer should have space for at least BASE64_GUID_ID_LEN characters. The string will always be null terminated. XXXXXXXXXXXXXXXXXXXXXXXX0
*/ static HRESULT create_unique_font_name(char* buffer, size_t bufferSize) {
GUID guid = {}; if (FAILED(CoCreateGuid(&guid))) { return E_UNEXPECTED;
}
format_guid_b64(guid, buffer, bufferSize);
return S_OK;
}
/** Introduces a font to GDI. On failure will return nullptr. The returned handle should eventually be passed to RemoveFontMemResourceEx.
*/ static HANDLE activate_font(SkData* fontData) {
DWORD numFonts = 0; //AddFontMemResourceEx just copies the data, but does not specify const.
HANDLE fontHandle = AddFontMemResourceEx(const_cast<void*>(fontData->data()), static_cast<DWORD>(fontData->size()),
nullptr,
&numFonts);
// Does not affect ownership of stream. static sk_sp<SkTypeface> create_from_stream(std::unique_ptr<SkStreamAsset> stream) { // Create a unique and unpredictable font name. // Avoids collisions and access from CSS. char familyName[BASE64_GUID_ID_LEN]; constint familyNameSize = std::size(familyName); if (FAILED(create_unique_font_name(familyName, familyNameSize))) { return nullptr;
}
// Change the name of the font.
sk_sp<SkData> rewrittenFontData(SkOTUtils::RenameFont(stream.get(), familyName, familyNameSize-1)); if (nullptr == rewrittenFontData.get()) { return nullptr;
}
// Register the font with GDI.
HANDLE fontReference = activate_font(rewrittenFontData.get()); if (nullptr == fontReference) { return nullptr;
}
// Create the typeface.
LOGFONT lf;
logfont_for_name(familyName, &lf);
staticvoid bmpCharsToGlyphs(HDC hdc, const WCHAR* bmpChars, int count, uint16_t* glyphs, bool Ox1FHack)
{ // Type1 fonts fail with uniscribe API. Use GetGlyphIndices for plane 0.
/** Real documentation for GetGlyphIndicesW: * * When GGI_MARK_NONEXISTING_GLYPHS is not specified and a character does not map to a * glyph, then the 'default character's glyph is returned instead. The 'default character' * is available in fTM.tmDefaultChar. FON fonts have a default character, and there exists * a usDefaultChar in the 'OS/2' table, version 2 and later. If there is no * 'default character' specified by the font, then often the first character found is used. * * When GGI_MARK_NONEXISTING_GLYPHS is specified and a character does not map to a glyph, * then the glyph 0xFFFF is used. In Windows XP and earlier, Bitmap/Vector FON usually use * glyph 0x1F instead ('Terminal' appears to be special, returning 0xFFFF). * Type1 PFM/PFB, TT, OT TT, OT CFF all appear to use 0xFFFF, even on XP.
*/
DWORD result = GetGlyphIndicesW(hdc, bmpChars, count, glyphs, GGI_MARK_NONEXISTING_GLYPHS); if (GDI_ERROR == result) { for (int i = 0; i < count; ++i) {
glyphs[i] = 0;
} return;
}
if (Ox1FHack) { for (int i = 0; i < count; ++i) { if (0xFFFF == glyphs[i] || 0x1F == glyphs[i]) {
glyphs[i] = 0;
}
}
} else { for (int i = 0; i < count; ++i) { if (0xFFFF == glyphs[i]){
glyphs[i] = 0;
}
}
}
}
static uint16_t nonBmpCharToGlyph(HDC hdc, SCRIPT_CACHE* scriptCache, const WCHAR utf16[2]) {
uint16_t index = 0; // Use uniscribe to detemine glyph index for non-BMP characters. staticconstint numWCHAR = 2; staticconstint maxItems = 2; // MSDN states that this can be nullptr, but some things don't work then.
SCRIPT_CONTROL scriptControl;
memset(&scriptControl, 0, sizeof(scriptControl)); // Add extra item to SCRIPT_ITEM to work around a bug (now documented). // https://bugzilla.mozilla.org/show_bug.cgi?id=366643
SCRIPT_ITEM si[maxItems + 1]; int numItems;
HRZM(ScriptItemize(utf16, numWCHAR, maxItems, &scriptControl, nullptr, si, &numItems), "Could not itemize character.");
// Sometimes ScriptShape cannot find a glyph for a non-BMP and returns 2 space glyphs. staticconstint maxGlyphs = 2;
SCRIPT_VISATTR vsa[maxGlyphs];
WORD outGlyphs[maxGlyphs];
WORD logClust[numWCHAR]; int numGlyphs;
SCRIPT_ANALYSIS& script = si[0].a;
script.eScript = SCRIPT_UNDEFINED;
script.fRTL = FALSE;
script.fLayoutRTL = FALSE;
script.fLinkBefore = FALSE;
script.fLinkAfter = FALSE;
script.fLogicalOrder = FALSE;
script.fNoGlyphIndex = FALSE;
script.s.uBidiLevel = 0;
script.s.fOverrideDirection = 0;
script.s.fInhibitSymSwap = TRUE;
script.s.fCharShape = FALSE;
script.s.fDigitSubstitute = FALSE;
script.s.fInhibitLigate = FALSE;
script.s.fDisplayZWG = TRUE;
script.s.fArabicNumContext = FALSE;
script.s.fGcpClusters = FALSE;
script.s.fReserved = 0;
script.s.fEngineReserved = 0; // For the future, 0x80040200 from here is USP_E_SCRIPT_NOT_IN_FONT
HRZM(ScriptShape(hdc, scriptCache, utf16, numWCHAR, maxGlyphs, &script,
outGlyphs, logClust, vsa, &numGlyphs), "Could not shape character."); if (1 == numGlyphs) {
index = outGlyphs[0];
} return index;
}
SkFontHinting h = rec->getHinting(); switch (h) { case SkFontHinting::kNone: break; case SkFontHinting::kSlight: // Only do slight hinting when axis aligned. // TODO: re-enable slight hinting when FontHostTest can pass. //if (!isAxisAligned(*rec)) {
h = SkFontHinting::kNone; //} break; case SkFontHinting::kNormal: case SkFontHinting::kFull: // TODO: need to be able to distinguish subpixel positioned glyphs // and linear metrics. //rec->fFlags &= ~SkScalerContext::kSubpixelPositioning_Flag;
h = SkFontHinting::kNormal; break; default:
SkDEBUGFAIL("unknown hinting");
} //TODO: if this is a bitmap font, squash hinting and subpixel.
rec->setHinting(h);
// turn this off since GDI might turn A8 into BW! Need a bigger fix. #if 0 // Disable LCD when rotated, since GDI's output is ugly if (isLCD(*rec) && !isAxisAligned(*rec)) {
rec->fMaskFormat = SkMask::kA8_Format;
} #endif
if (!fCanBeLCD && isLCD(*rec)) {
rec->fMaskFormat = SkMask::kA8_Format;
rec->fFlags &= ~SkScalerContext::kGenA8FromLCD_Flag;
} elseif (rec->fMaskFormat == SkMask::kA8_Format) { // Bug 1277404 // If we have non LCD GDI text, render the fonts as cleartype and convert them // to grayscale. This seems to be what Chrome and IE are doing on Windows 7. // This also applies if cleartype is disabled system wide.
rec->fFlags |= SkScalerContext::kGenA8FromLCD_Flag;
}
}
staticbool valid_logfont_for_enum(const LOGFONT& lf) { // TODO: Vector FON is unsupported and should not be listed. return // Ignore implicit vertical variants.
lf.lfFaceName[0] && lf.lfFaceName[0] != '@'
// DEFAULT_CHARSET is used to get all fonts, but also implies all // character sets. Filter assuming all fonts support ANSI_CHARSET.
&& ANSI_CHARSET == lf.lfCharSet
;
}
/** An EnumFontFamExProc implementation which interprets builderParam as * an SkTDArray<ENUMLOGFONTEX>* and appends logfonts which * pass the valid_logfont_for_enum predicate.
*/ staticint CALLBACK enum_family_proc(const LOGFONT* lf, const TEXTMETRIC*,
DWORD fontType, LPARAM builderParam) { if (valid_logfont_for_enum(*lf)) {
SkTDArray<ENUMLOGFONTEX>* array = (SkTDArray<ENUMLOGFONTEX>*)builderParam;
*array->append() = *(const ENUMLOGFONTEX*)lf;
} return 1; // non-zero means continue
}
class SkFontStyleSetGDI : public SkFontStyleSet { public:
SkFontStyleSetGDI(const TCHAR familyName[]) {
LOGFONT lf;
sk_bzero(&lf, sizeof(lf));
lf.lfCharSet = DEFAULT_CHARSET;
_tcscpy_s(lf.lfFaceName, familyName);
void getStyle(int index, SkFontStyle* fs, SkString* styleName) override { if (fs) {
*fs = get_style(fArray[index].elfLogFont);
} if (styleName) { const ENUMLOGFONTEX& ref = fArray[index]; // For some reason, ENUMLOGFONTEX and LOGFONT disagree on their type in the // non-unicode version. // ENUMLOGFONTEX uses BYTE // LOGFONT uses CHAR // Here we assert they that the style name is logically the same (size) as // a TCHAR, so we can use the same converter function.
SkASSERT(sizeof(TCHAR) == sizeof(ref.elfStyle[0]));
tchar_to_skstring((const TCHAR*)ref.elfStyle, styleName);
}
}
sk_sp<SkFontStyleSet> onMatchFamily(constchar familyName[]) const override { if (nullptr == familyName) {
familyName = ""; // do we need this check???
}
LOGFONT lf;
logfont_for_name(familyName, &lf); return sk_sp<SkFontStyleSet>(new SkFontStyleSetGDI(lf.lfFaceName));
}
sk_sp<SkTypeface> onMatchFamilyStyle(constchar familyName[], const SkFontStyle& fontstyle) const override { // could be in base impl
sk_sp<SkFontStyleSet> sset(this->matchFamily(familyName)); return sset->matchStyle(fontstyle);
}
sk_sp<SkTypeface> onMakeFromData(sk_sp<SkData> data, int ttcIndex) const override { // could be in base impl return this->makeFromStream(std::unique_ptr<SkStreamAsset>(new SkMemoryStream(std::move(data))),
ttcIndex);
}
sk_sp<SkTypeface> onMakeFromFile(constchar path[], int ttcIndex) const override { // could be in base impl auto stream = SkStream::MakeFromFile(path); return stream ? this->makeFromStream(std::move(stream), ttcIndex) : nullptr;
}
