static int computePaintTextFlags(const LOGFONT& lf)
{
int textFlags = 0;
switch (lf.lfQuality) {
case NONANTIALIASED_QUALITY:
textFlags = 0;
break;
case ANTIALIASED_QUALITY:
textFlags = SkPaint::kAntiAlias_Flag;
break;
case CLEARTYPE_QUALITY:
textFlags = (SkPaint::kAntiAlias_Flag | SkPaint::kLCDRenderText_Flag);
break;
default:
textFlags = getDefaultGDITextFlags();
break;
}
// only allow features that SystemParametersInfo allows
textFlags &= getDefaultGDITextFlags();
/*
* FontPlatformData(...) will read our logfont, and try to honor the the lfQuality
* setting (computing the corresponding SkPaint flags for AA and LCD). However, it
* will limit the quality based on its query of SPI_GETFONTSMOOTHING. This could mean
* we end up drawing the text in BW, even though our lfQuality requested antialiasing.
*
* Many web-fonts are so poorly hinted that they are terrible to read when drawn in BW.
* In these cases, we have decided to FORCE these fonts to be drawn with at least grayscale AA,
* even when the System (getDefaultGDITextFlags) tells us to draw only in BW.
*/
if (isWebFont(lf) && !isRunningLayoutTest())
textFlags |= SkPaint::kAntiAlias_Flag;
return textFlags;
}
static void setupPaintForFont(HFONT hfont, SkPaint* paint, PlatformContextSkia* pcs)
{
// FIXME:
// Much of this logic could also happen in
// FontCustomPlatformData::fontPlatformData and be cached,
// allowing us to avoid talking to GDI at this point.
//
LOGFONT info;
GetObject(hfont, sizeof(info), &info);
int size = info.lfHeight;
if (size < 0)
size = -size; // We don't let GDI dpi-scale us (see SkFontHost_win.cpp).
paint->setTextSize(SkIntToScalar(size));
SkTypeface* face = SkCreateTypefaceFromLOGFONT(info);
paint->setTypeface(face);
SkSafeUnref(face);
// turn lfQuality into text flags
uint32_t textFlags;
switch (info.lfQuality) {
case NONANTIALIASED_QUALITY:
textFlags = 0;
break;
case ANTIALIASED_QUALITY:
textFlags = SkPaint::kAntiAlias_Flag;
break;
case CLEARTYPE_QUALITY:
textFlags = (SkPaint::kAntiAlias_Flag | SkPaint::kLCDRenderText_Flag);
break;
default:
textFlags = getDefaultGDITextFlags();
break;
}
// only allow features that SystemParametersInfo allows
textFlags &= getDefaultGDITextFlags();
// do this check after our switch on lfQuality
if (disableTextLCD(pcs))
textFlags &= ~SkPaint::kLCDRenderText_Flag;
// now copy in just the text flags
uint32_t flags = paint->getFlags();
flags &= ~(SkPaint::kAntiAlias_Flag | SkPaint::kLCDRenderText_Flag);
flags |= textFlags;
paint->setFlags(flags);
}
static void setupPaintForFont(SkPaint* paint, PlatformContextSkia* pcs,
SkTypeface* face, float size, int quality)
{
paint->setTextSize(SkFloatToScalar(size));
paint->setTypeface(face);
// turn quality into text flags
uint32_t textFlags;
switch (quality) {
case NONANTIALIASED_QUALITY:
textFlags = 0;
break;
case ANTIALIASED_QUALITY:
textFlags = SkPaint::kAntiAlias_Flag;
break;
case CLEARTYPE_QUALITY:
textFlags = (SkPaint::kAntiAlias_Flag | SkPaint::kLCDRenderText_Flag);
break;
default:
textFlags = getDefaultGDITextFlags();
break;
}
// only allow features that SystemParametersInfo allows
textFlags &= getDefaultGDITextFlags();
// do this check after our switch on lfQuality
if (!pcs->couldUseLCDRenderedText()) {
textFlags &= ~SkPaint::kLCDRenderText_Flag;
// If we *just* clear our request for LCD, then GDI seems to
// sometimes give us AA text, and sometimes give us BW text. Since the
// original intent was LCD, we want to force AA (rather than BW), so we
// add a special bit to tell Skia to do its best to avoid the BW: by
// drawing LCD offscreen and downsampling that to AA.
textFlags |= SkPaint::kGenA8FromLCD_Flag;
}
static const uint32_t textFlagsMask = SkPaint::kAntiAlias_Flag |
SkPaint::kLCDRenderText_Flag |
SkPaint::kGenA8FromLCD_Flag;
// now copy in just the text flags
SkASSERT(!(textFlags & ~textFlagsMask));
uint32_t flags = paint->getFlags();
flags &= ~textFlagsMask;
flags |= textFlags;
paint->setFlags(flags);
}
static void setupPaintForFont(HFONT hfont, SkPaint* paint, PlatformContextSkia* pcs)
{
// FIXME:
// Much of this logic could also happen in
// FontCustomPlatformData::fontPlatformData and be cached,
// allowing us to avoid talking to GDI at this point.
//
LOGFONT info;
GetObject(hfont, sizeof(info), &info);
int size = info.lfHeight;
if (size < 0)
size = -size; // We don't let GDI dpi-scale us (see SkFontHost_win.cpp).
paint->setTextSize(SkIntToScalar(size));
SkTypeface* face = SkCreateTypefaceFromLOGFONT(info);
paint->setTypeface(face);
SkSafeUnref(face);
uint32_t flags = paint->getFlags();
// clear our flags initially, and then selectively set them
// based on the LOGFONT quality
flags &= SkPaint::kAntiAlias_Flag;
flags &= SkPaint::kLCDRenderText_Flag;
switch (info.lfQuality) {
case NONANTIALIASED_QUALITY:
break;
case ANTIALIASED_QUALITY:
flags |= SkPaint::kAntiAlias_Flag;
break;
case CLEARTYPE_QUALITY:
flags |= SkPaint::kAntiAlias_Flag;
flags |= SkPaint::kLCDRenderText_Flag;
break;
default:
flags |= getDefaultGDITextFlags();
break;
}
// do this check after our switch on lfQuality
if (disableTextLCD(pcs))
flags &= ~SkPaint::kLCDRenderText_Flag;
paint->setFlags(flags);
}
