Revert of Revert of Fix SkTextBlob offset semantics. (patchset #1 id:1 of https://codereview.chromium.org/609223003/)

Reason for revert:
Re-landing: Chromium-side fix to be landed with the roll (https://codereview.chromium.org/607853003/)

Original issue's description:
> Revert of Fix SkTextBlob offset semantics. (patchset #2 id:20001 of https://codereview.chromium.org/605533002/)
>
> Reason for revert:
> Breaking the Chrome builds with the error:
>
> [14:54:14.317833] ../../skia/ext/pixel_ref_utils.cc:221:16: error: 'drawPosText' marked 'override' but does not override any member functions
> [14:54:14.318022]   virtual void drawPosText(const SkDraw& draw,
> [14:54:14.318082]                ^
>
> Original issue's description:
> > Fix SkTextBlob offset semantics.
> >
> > Implement proper x/y drawTextBlob() handling by plumbing a
> > drawPosText() offset parameter (to act as an additional glyph pos
> > translation) throughout the device layer.
> >
> > The new offset superceeds the existing constY, with a minor semantic
> > tweak: whereas previous implementations were ignoring constY in 2D
> > positioning mode (scalarsPerGlyph == 2), now the offset is always
> > observed, in all positioning modes. We can do this because existing
> > drawPosText() clients always pass constY == 0 for full positioning mode.
> >
> > R=reed@google.com, jvanverth@google.com, robertphillips@google.com
> >
> > Committed: https://skia.googlesource.com/skia/+/c13bc571d3e61a43b87eb97f0719abd304cafaf2
>
> TBR=jvanverth@google.com,reed@google.com,bsalomon@google.com,fmalita@chromium.org
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://skia.googlesource.com/skia/+/d46b8d2bab7cfba8458432248e1568ac377429e9

R=jvanverth@google.com, reed@google.com, bsalomon@google.com, robertphillips@google.com
TBR=bsalomon@google.com, jvanverth@google.com, reed@google.com, robertphillips@google.com
NOTREECHECKS=true
NOTRY=true

Author: fmalita@chromium.org

Review URL: https://codereview.chromium.org/607413003

9 files changed, 34 insertions, 37 deletions

diff --git a/src/gpu/GrBitmapTextContext.cpp b/src/gpu/GrBitmapTextContext.cpp
index 82784bf0e3..0f6d1b62a9 100755
--- a/src/gpu/GrBitmapTextContext.cpp
+++ b/src/gpu/GrBitmapTextContext.cpp
@@ -270,8 +270,8 @@ void GrBitmapTextContext::drawText(const GrPaint& paint, const SkPaint& skPaint,
 
 void GrBitmapTextContext::drawPosText(const GrPaint& paint, const SkPaint& skPaint,
                                       const char text[], size_t byteLength,
-                                      const SkScalar pos[], SkScalar constY,
-                                      int scalarsPerPosition) {
+                                      const SkScalar pos[], int scalarsPerPosition,
+                                      const SkPoint& offset) {
     SkASSERT(byteLength == 0 || text != NULL);
     SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
 
@@ -295,7 +295,7 @@ void GrBitmapTextContext::drawPosText(const GrPaint& paint, const SkPaint& skPai
 
     const char*        stop = text + byteLength;
     SkTextAlignProc    alignProc(fSkPaint.getTextAlign());
-    SkTextMapStateProc tmsProc(ctm, constY, scalarsPerPosition);
+    SkTextMapStateProc tmsProc(ctm, offset, scalarsPerPosition);
     SkFixed halfSampleX = 0, halfSampleY = 0;
 
     if (cache->isSubpixel()) {
diff --git a/src/gpu/GrBitmapTextContext.h b/src/gpu/GrBitmapTextContext.h
index 80abf681f4..c136270c65 100644
--- a/src/gpu/GrBitmapTextContext.h
+++ b/src/gpu/GrBitmapTextContext.h
@@ -25,8 +25,8 @@ public:
                           SkScalar x, SkScalar y) SK_OVERRIDE;
     virtual void drawPosText(const GrPaint&, const SkPaint&,
                              const char text[], size_t byteLength,
-                             const SkScalar pos[], SkScalar constY,
-                             int scalarsPerPosition) SK_OVERRIDE;
+                             const SkScalar pos[], int scalarsPerPosition,
+                             const SkPoint& offset) SK_OVERRIDE;
 
     virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE;
 
diff --git a/src/gpu/GrDistanceFieldTextContext.cpp b/src/gpu/GrDistanceFieldTextContext.cpp
index 9fd024af9f..e2bd6e9f9c 100755
--- a/src/gpu/GrDistanceFieldTextContext.cpp
+++ b/src/gpu/GrDistanceFieldTextContext.cpp
@@ -609,8 +609,8 @@ void GrDistanceFieldTextContext::drawText(const GrPaint& paint, const SkPaint& s
 
 void GrDistanceFieldTextContext::drawPosText(const GrPaint& paint, const SkPaint& skPaint,
                                              const char text[], size_t byteLength,
-                                             const SkScalar pos[], SkScalar constY,
-                                             int scalarsPerPosition) {
+                                             const SkScalar pos[], int scalarsPerPosition,
+                                             const SkPoint& offset) {
 
     SkASSERT(byteLength == 0 || text != NULL);
     SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
@@ -638,8 +638,8 @@ void GrDistanceFieldTextContext::drawPosText(const GrPaint& paint, const SkPaint
             const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0);
 
             if (glyph.fWidth) {
-                SkScalar x = pos[0];
-                SkScalar y = scalarsPerPosition == 1 ? constY : pos[1];
+                SkScalar x = offset.x() + pos[0];
+                SkScalar y = offset.y() + (2 == scalarsPerPosition ? pos[1] : 0);
 
                 this->drawPackedGlyph(GrGlyph::Pack(glyph.getGlyphID(),
                                                     glyph.getSubXFixed(),
@@ -657,8 +657,8 @@ void GrDistanceFieldTextContext::drawPosText(const GrPaint& paint, const SkPaint
             const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0);
 
             if (glyph.fWidth) {
-                SkScalar x = pos[0];
-                SkScalar y = scalarsPerPosition == 1 ? constY : pos[1];
+                SkScalar x = offset.x() + pos[0];
+                SkScalar y = offset.y() + (2 == scalarsPerPosition ? pos[1] : 0);
 
                 this->drawPackedGlyph(GrGlyph::Pack(glyph.getGlyphID(),
                                                     glyph.getSubXFixed(),
diff --git a/src/gpu/GrDistanceFieldTextContext.h b/src/gpu/GrDistanceFieldTextContext.h
index 85d9250e44..0b08b5986c 100644
--- a/src/gpu/GrDistanceFieldTextContext.h
+++ b/src/gpu/GrDistanceFieldTextContext.h
@@ -25,8 +25,8 @@ public:
                           SkScalar x, SkScalar y) SK_OVERRIDE;
     virtual void drawPosText(const GrPaint&, const SkPaint&,
                              const char text[], size_t byteLength,
-                             const SkScalar pos[], SkScalar constY,
-                             int scalarsPerPosition) SK_OVERRIDE;
+                             const SkScalar pos[], int scalarsPerPosition,
+                             const SkPoint& offset) SK_OVERRIDE;
 
     virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE;
 
diff --git a/src/gpu/GrStencilAndCoverTextContext.cpp b/src/gpu/GrStencilAndCoverTextContext.cpp
index c1d9e9d32d..cfcabe923f 100644
--- a/src/gpu/GrStencilAndCoverTextContext.cpp
+++ b/src/gpu/GrStencilAndCoverTextContext.cpp
@@ -54,7 +54,7 @@ void GrStencilAndCoverTextContext::drawText(const GrPaint& paint,
     // will turn off the use of device-space glyphs when perspective transforms
     // are in use.
 
-    this->init(paint, skPaint, byteLength, kMaxAccuracy_RenderMode);
+    this->init(paint, skPaint, byteLength, kMaxAccuracy_RenderMode, SkPoint::Make(0, 0));
 
     // Transform our starting point.
     if (fNeedsDeviceSpaceGlyphs) {
@@ -123,8 +123,8 @@ void GrStencilAndCoverTextContext::drawPosText(const GrPaint& paint,
                                                const char text[],
                                                size_t byteLength,
                                                const SkScalar pos[],
-                                               SkScalar constY,
-                                               int scalarsPerPosition) {
+                                               int scalarsPerPosition,
+                                               const SkPoint& offset) {
     SkASSERT(byteLength == 0 || text != NULL);
     SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
 
@@ -141,8 +141,7 @@ void GrStencilAndCoverTextContext::drawPosText(const GrPaint& paint,
     // transform is not part of SkPaint::measureText API, and thus we use the
     // same glyphs as what were measured.
 
-    const float textTranslateY = (1 == scalarsPerPosition ? constY : 0);
-    this->init(paint, skPaint, byteLength, kMaxPerformance_RenderMode, textTranslateY);
+    this->init(paint, skPaint, byteLength, kMaxPerformance_RenderMode, offset);
 
     SkDrawCacheProc glyphCacheProc = fSkPaint.getDrawCacheProc();
 
@@ -171,7 +170,7 @@ void GrStencilAndCoverTextContext::drawPosText(const GrPaint& paint,
         }
     } else {
         fTransformType = GrPathRendering::kTranslate_PathTransformType;
-        SkTextMapStateProc tmsProc(SkMatrix::I(), 0, scalarsPerPosition);
+        SkTextMapStateProc tmsProc(SkMatrix::I(), SkPoint::Make(0, 0), scalarsPerPosition);
         SkTextAlignProcScalar alignProc(fSkPaint.getTextAlign());
         while (text < stop) {
             const SkGlyph& glyph = glyphCacheProc(fGlyphCache, &text, 0, 0);
@@ -242,7 +241,7 @@ void GrStencilAndCoverTextContext::init(const GrPaint& paint,
                                         const SkPaint& skPaint,
                                         size_t textByteLength,
                                         RenderMode renderMode,
-                                        SkScalar textTranslateY) {
+                                        const SkPoint& textTranslate) {
     GrTextContext::init(paint, skPaint);
 
     fContextInitialMatrix = fContext->getMatrix();
@@ -258,7 +257,7 @@ void GrStencilAndCoverTextContext::init(const GrPaint& paint,
     if (fNeedsDeviceSpaceGlyphs) {
         // SkDraw::ShouldDrawTextAsPaths takes care of perspective transforms.
         SkASSERT(!fContextInitialMatrix.hasPerspective());
-        SkASSERT(0 == textTranslateY); // TODO: Handle textTranslateY in device-space usecase.
+        SkASSERT(textTranslate.isZero()); // TODO: Handle textTranslate in device-space usecase.
 
         fTextRatio = fTextInverseRatio = 1.0f;
 
@@ -340,7 +339,7 @@ void GrStencilAndCoverTextContext::init(const GrPaint& paint,
         }
 
         SkMatrix textMatrix;
-        textMatrix.setTranslate(0, textTranslateY);
+        textMatrix.setTranslate(textTranslate.x(), textTranslate.y());
         // Glyphs loaded by GPU path rendering have an inverted y-direction.
         textMatrix.preScale(fTextRatio, -fTextRatio);
         fPaint.localCoordChange(textMatrix);
diff --git a/src/gpu/GrStencilAndCoverTextContext.h b/src/gpu/GrStencilAndCoverTextContext.h
index 5ba4a7027b..b6e23bdb3f 100644
--- a/src/gpu/GrStencilAndCoverTextContext.h
+++ b/src/gpu/GrStencilAndCoverTextContext.h
@@ -32,8 +32,8 @@ public:
                           SkScalar x, SkScalar y) SK_OVERRIDE;
     virtual void drawPosText(const GrPaint&, const SkPaint&,
                              const char text[], size_t byteLength,
-                             const SkScalar pos[], SkScalar constY,
-                             int scalarsPerPosition) SK_OVERRIDE;
+                             const SkScalar pos[], int scalarsPerPosition,
+                             const SkPoint& offset) SK_OVERRIDE;
 
     virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE;
 
@@ -62,7 +62,7 @@ private:
     };
 
     void init(const GrPaint&, const SkPaint&, size_t textByteLength,
-              RenderMode, SkScalar textTranslateY = 0);
+              RenderMode, const SkPoint& textTranslate);
     void initGlyphs(SkGlyphCache* cache);
     void appendGlyph(uint16_t glyphID, float x);
     void appendGlyph(uint16_t glyphID, float x, float y);
diff --git a/src/gpu/GrTextContext.h b/src/gpu/GrTextContext.h
index c139e22295..da41c1bb3c 100644
--- a/src/gpu/GrTextContext.h
+++ b/src/gpu/GrTextContext.h
@@ -28,8 +28,8 @@ public:
                           SkScalar x, SkScalar y) = 0;
     virtual void drawPosText(const GrPaint&, const SkPaint&,
                              const char text[], size_t byteLength,
-                             const SkScalar pos[], SkScalar constY,
-                             int scalarsPerPosition) = 0;
+                             const SkScalar pos[], int scalarsPerPosition,
+                             const SkPoint& offset) = 0;
 
     virtual bool canDraw(const SkPaint& paint) = 0;
 
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index bd075cfd97..30b3668d6b 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -1713,10 +1713,9 @@ void SkGpuDevice::drawText(const SkDraw& draw, const void* text,
     }
 }
 
-void SkGpuDevice::drawPosText(const SkDraw& draw, const void* text,
-                             size_t byteLength, const SkScalar pos[],
-                             SkScalar constY, int scalarsPerPos,
-                             const SkPaint& paint) {
+void SkGpuDevice::drawPosText(const SkDraw& draw, const void* text, size_t byteLength,
+                              const SkScalar pos[], int scalarsPerPos,
+                              const SkPoint& offset, const SkPaint& paint) {
     GR_CREATE_TRACE_MARKER_CONTEXT("SkGpuDevice::drawPosText", fContext);
     CHECK_SHOULD_DRAW(draw, false);
 
@@ -1727,7 +1726,7 @@ void SkGpuDevice::drawPosText(const SkDraw& draw, const void* text,
         SkDEBUGCODE(this->validate();)
 
         fMainTextContext->drawPosText(grPaint, paint, (const char *)text, byteLength, pos,
-                                      constY, scalarsPerPos);
+                                      scalarsPerPos, offset);
     } else if (fFallbackTextContext && fFallbackTextContext->canDraw(paint)) {
         GrPaint grPaint;
         SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
@@ -1735,10 +1734,9 @@ void SkGpuDevice::drawPosText(const SkDraw& draw, const void* text,
         SkDEBUGCODE(this->validate();)
 
         fFallbackTextContext->drawPosText(grPaint, paint, (const char *)text, byteLength, pos,
-                                          constY, scalarsPerPos);
+                                          scalarsPerPos, offset);
     } else {
-        draw.drawPosText_asPaths((const char*)text, byteLength, pos, constY,
-                                 scalarsPerPos, paint);
+        draw.drawPosText_asPaths((const char*)text, byteLength, pos, scalarsPerPos, offset, paint);
     }
 }
 
diff --git a/src/gpu/SkGpuDevice.h b/src/gpu/SkGpuDevice.h
index 41b53b1213..f19d2cb62b 100644
--- a/src/gpu/SkGpuDevice.h
+++ b/src/gpu/SkGpuDevice.h
@@ -90,8 +90,8 @@ public:
     virtual void drawText(const SkDraw&, const void* text, size_t len,
                           SkScalar x, SkScalar y, const SkPaint&) SK_OVERRIDE;
     virtual void drawPosText(const SkDraw&, const void* text, size_t len,
-                             const SkScalar pos[], SkScalar constY,
-                             int scalarsPerPos, const SkPaint&) SK_OVERRIDE;
+                             const SkScalar pos[], int scalarsPerPos,
+                             const SkPoint& offset, const SkPaint&) SK_OVERRIDE;
     virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len,
                                 const SkPath& path, const SkMatrix* matrix,
                                 const SkPaint&) SK_OVERRIDE;