Detect that we're drawing to a device that has per-pixel alpha, and if so,
disable LCD text.
Add experimental flag to force AA in fontscaler (windows-only). Hope to remove
this later.
git-svn-id: http://skia.googlecode.com/svn/trunk@2387 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/core/SkBlitter_ARGB32.cpp b/src/core/SkBlitter_ARGB32.cpp
index af55aba..4e2916a 100644
--- a/src/core/SkBlitter_ARGB32.cpp
+++ b/src/core/SkBlitter_ARGB32.cpp
@@ -60,18 +60,16 @@
maskG = maskG * srcA >> 8;
maskB = maskB * srcA >> 8;
- int maskA = SkMax32(SkMax32(maskR, maskG), maskB);
-
- int dstA = SkGetPackedA32(d);
int dstR = SkGetPackedR32(d);
int dstG = SkGetPackedG32(d);
int dstB = SkGetPackedB32(d);
- // nocheck version for now, until we cleanup GDI's garbage bits
- dst[i] = SkPackARGB32NoCheck(blend32(0xFF, dstA, maskA),
- blend32(srcR, dstR, maskR),
- blend32(srcG, dstG, maskG),
- blend32(srcB, dstB, maskB));
+ // LCD blitting is only supported if the dst is known/required\
+ // to be opaque
+ dst[i] = SkPackARGB32(0xFF,
+ blend32(srcR, dstR, maskR),
+ blend32(srcG, dstG, maskG),
+ blend32(srcB, dstB, maskB));
}
}
@@ -105,18 +103,16 @@
maskG = upscale31To32(maskG);
maskB = upscale31To32(maskB);
- int maskA = SkMax32(SkMax32(maskR, maskG), maskB);
-
- int dstA = SkGetPackedA32(d);
int dstR = SkGetPackedR32(d);
int dstG = SkGetPackedG32(d);
int dstB = SkGetPackedB32(d);
- // nocheck version for now, until we cleanup GDI's garbage bits
- dst[i] = SkPackARGB32NoCheck(blend32(0xFF, dstA, maskA),
- blend32(srcR, dstR, maskR),
- blend32(srcG, dstG, maskG),
- blend32(srcB, dstB, maskB));
+ // LCD blitting is only supported if the dst is known/required
+ // to be opaque
+ dst[i] = SkPackARGB32(0xFF,
+ blend32(srcR, dstR, maskR),
+ blend32(srcG, dstG, maskG),
+ blend32(srcB, dstB, maskB));
}
}
@@ -150,14 +146,13 @@
maskG = maskG * srcA >> 8;
maskB = maskB * srcA >> 8;
- int maskA = SkMax32(SkMax32(maskR, maskG), maskB);
-
- int dstA = SkGetPackedA32(d);
int dstR = SkGetPackedR32(d);
int dstG = SkGetPackedG32(d);
int dstB = SkGetPackedB32(d);
- dst[i] = SkPackARGB32(SkAlphaBlend(0xFF, dstA, maskA),
+ // LCD blitting is only supported if the dst is known/required
+ // to be opaque
+ dst[i] = SkPackARGB32(0xFF,
SkAlphaBlend(srcR, dstR, maskR),
SkAlphaBlend(srcG, dstG, maskG),
SkAlphaBlend(srcB, dstB, maskB));
diff --git a/src/core/SkDevice.cpp b/src/core/SkDevice.cpp
index 69f86cc..c88ad9a 100644
--- a/src/core/SkDevice.cpp
+++ b/src/core/SkDevice.cpp
@@ -219,12 +219,13 @@
///////////////////////////////////////////////////////////////////////////////
bool SkDevice::filterTextFlags(const SkPaint& paint, TextFlags* flags) {
- if (!paint.isLCDRenderText()) {
+ if (!paint.isLCDRenderText() || !paint.isAntiAlias()) {
// we're cool with the paint as is
return false;
}
if (SkBitmap::kARGB_8888_Config != fBitmap.config() ||
+ !fBitmap.isOpaque() ||
paint.getShader() ||
paint.getXfermode() || // unless its srcover
paint.getMaskFilter() ||
@@ -235,6 +236,10 @@
paint.getStyle() != SkPaint::kFill_Style) {
// turn off lcd
flags->fFlags = paint.getFlags() & ~SkPaint::kLCDRenderText_Flag;
+#ifdef SK_BUILD_FOR_WIN
+ // flag that we *really* want AA
+ flags->fFlags |= SkPaint::kForceAAText_Flag;
+#endif
flags->fHinting = paint.getHinting();
return true;
}
diff --git a/src/core/SkPaint.cpp b/src/core/SkPaint.cpp
index 9197add..b2f5d8e 100644
--- a/src/core/SkPaint.cpp
+++ b/src/core/SkPaint.cpp
@@ -1340,6 +1340,11 @@
if (paint.isAutohinted()) {
flags |= SkScalerContext::kAutohinting_Flag;
}
+#ifdef SK_BUILD_FOR_WIN
+ if (paint.getFlags() & SkPaint::kForceAAText_Flag) {
+ flags |= SkScalerContext::kForceAA_Flag;
+ }
+#endif
rec->fFlags = SkToU16(flags);
// setHinting modifies fFlags, so do this last
diff --git a/src/ports/SkFontHost_win.cpp b/src/ports/SkFontHost_win.cpp
index e265c13..87dbb80 100755
--- a/src/ports/SkFontHost_win.cpp
+++ b/src/ports/SkFontHost_win.cpp
@@ -31,11 +31,6 @@
return (T*)((char*)ptr + byteOffset);
}
-// When we request ANTIALIAS quality, we often seemt to get BW instead
-// This flag "fixes" that by actually requesting LCD output, and filtering
-// it down to gray-aa
-#define FORCE_AA_BY_CAPTURING_LCD_OUTPUT
-
// 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.
@@ -483,11 +478,15 @@
case SkMask::kLCD32_Format:
return CLEARTYPE_QUALITY;
default:
-#ifdef FORCE_AA_BY_CAPTURING_LCD_OUTPUT
- return CLEARTYPE_QUALITY;
-#else
- return ANTIALIASED_QUALITY;
-#endif
+ // here we just want AA, but we may have to force the issue
+ // since sometimes GDI will instead really give us BW
+ // (for some fonts and some sizes)
+ if (rec.fFlags & SkScalerContext::kForceAA_Flag) {
+ return CLEARTYPE_QUALITY;
+ } else {
+ return ANTIALIASED_QUALITY;
+ }
+ break;
}
}
@@ -697,19 +696,11 @@
// whenever we copy it into skia's buffer
static inline uint8_t rgb_to_a8(SkGdiRGB rgb) {
-#ifdef FORCE_AA_BY_CAPTURING_LCD_OUTPUT
int r = (rgb >> 16) & 0xFF;
int g = (rgb >> 8) & 0xFF;
int b = (rgb >> 0) & 0xFF;
-// int ave = (r * 5 + g * 6 + b * 5) >> 4;
- int ave = (r * 2 + g * 5 + b) >> 3; // luminance
-
- return ave;
-#else
- // can pick any component (low 3 bytes), since we're grayscale
- return rgb & 0xFF;
-#endif
+ return (r * 2 + g * 5 + b) >> 3; // luminance
}
static inline uint16_t rgb_to_lcd16(SkGdiRGB rgb) {
@@ -1309,6 +1300,11 @@
rec->fMaskFormat = SkMask::kLCD32_Format;
}
#endif
+ // don't specify gamma if we BW (perhaps caller should do this check)
+ if (SkMask::kBW_Format == rec->fMaskFormat) {
+ rec->fFlags &= ~(SkScalerContext::kGammaForBlack_Flag |
+ SkScalerContext::kGammaForWhite_Flag);
+ }
}
//////////////////////////////////////////////////////////////////////////