Support BGR with DirectWrite.

src/ports/SkScalerContext_win_dw.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkTypes.h"
 #undef GetGlyphIndices
 
@@ skipping 573 matching lines @@
         for (U16CPU i = 0; i < width; i++) {
             U8CPU r = *(src++);
             U8CPU g = *(src++);
             U8CPU b = *(src++);
             dst[i] = sk_apply_lut_if<APPLY_PREBLEND>((r + g + b) / 3, table8);
         }
         dst = (uint8_t*)((char*)dst + dstRB);
     }
 }
 
-template<bool APPLY_PREBLEND>
+template<bool APPLY_PREBLEND, bool RGB>
 static void rgb_to_lcd16(const uint8_t* SK_RESTRICT src, const SkGlyph& glyph,
                          const uint8_t* tableR, const uint8_t* tableG, const uint8_t* tableB) {
     const size_t dstRB = glyph.rowBytes();
     const U16CPU width = glyph.fWidth;
     uint16_t* SK_RESTRICT dst = static_cast<uint16_t*>(glyph.fImage);
 
     for (U16CPU y = 0; y < glyph.fHeight; y++) {
         for (U16CPU i = 0; i < width; i++) {
-            U8CPU r = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableR);
-            U8CPU g = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableG);
-            U8CPU b = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableB);
+            U8CPU r, g, b;
+            if (RGB) {
+                r = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableR);
+                g = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableG);
+                b = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableB);
+            } else {
+                b = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableB);
+                g = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableG);
+                r = sk_apply_lut_if<APPLY_PREBLEND>(*(src++), tableR);
+            }
             dst[i] = SkPack888ToRGB16(r, g, b);
         }
         dst = (uint16_t*)((char*)dst + dstRB);
     }
 }
 
 const void* SkScalerContext_DW::drawDWMask(const SkGlyph& glyph,
                                            DWRITE_RENDERING_MODE renderingMode,
                                            DWRITE_TEXTURE_TYPE textureType)
 {
@@ skipping 76 matching lines @@
         const_cast<SkGlyph&>(glyph).fMaskFormat = SkMask::kBW_Format;
     } else if (!isLCD(fRec)) {
         if (fPreBlend.isApplicable()) {
             rgb_to_a8<true>(src, glyph, fPreBlend.fG);
         } else {
             rgb_to_a8<false>(src, glyph, fPreBlend.fG);
         }
     } else {
         SkASSERT(SkMask::kLCD16_Format == glyph.fMaskFormat);
         if (fPreBlend.isApplicable()) {
-            rgb_to_lcd16<true>(src, glyph, fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
+            if (fRec.fFlags & SkScalerContext::kLCD_BGROrder_Flag) {
+                rgb_to_lcd16<true, false>(src, glyph, fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
+            } else {
+                rgb_to_lcd16<true, true>(src, glyph, fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
+            }
         } else {
-            rgb_to_lcd16<false>(src, glyph, fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
+            if (fRec.fFlags & SkScalerContext::kLCD_BGROrder_Flag) {
+                rgb_to_lcd16<false, false>(src, glyph, fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
+            } else {
+                rgb_to_lcd16<false, true>(src, glyph, fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
+            }
         }
     }
 }
 
 void SkScalerContext_DW::generatePath(const SkGlyph& glyph, SkPath* path) {
     SkASSERT(&glyph && path);
 
     path->reset();
 
     SkTScopedComPtr<IDWriteGeometrySink> geometryToPath;
     HRVM(SkDWriteGeometrySink::Create(path, &geometryToPath),
          "Could not create geometry to path converter.");
     uint16_t glyphId = glyph.getGlyphID();
     //TODO: convert to<->from DIUs? This would make a difference if hinting.
     //It may not be needed, it appears that DirectWrite only hints at em size.
     HRVM(fTypeface->fDWriteFontFace->GetGlyphRunOutline(SkScalarToFloat(fTextSizeRender),
                                        &glyphId,
                                        NULL, //advances
                                        NULL, //offsets
                                        1, //num glyphs
                                        FALSE, //sideways
                                        FALSE, //rtl
                                        geometryToPath.get()),
          "Could not create glyph outline.");
 
     path->transform(fSkXform);
 }