fix negative font size

PDF can specify a negative font size
to change the y-axis for text. Add
support in the Skia driver for that.

The cached form for text and paths
had fallen out of sync with the uncached
code used by skiapaths, so sync that
up so that the mainline skia setting
has those bug fixes as well.

This does not fix the underlying bug in
528103, but gets Skia on parity with
native PDFium text rendering. The bold
text is still drawn in the wrong place.

R=dsinclair@chromium.org
BUG=528103

Review-Url: https://codereview.chromium.org/2528663002

1 files changed, 13 insertions, 10 deletions

diff --git a/core/fxge/skia/fx_skia_device.cpp b/core/fxge/skia/fx_skia_device.cpp
index 136bab71c6..5f46d0d93a 100644
--- a/core/fxge/skia/fx_skia_device.cpp
+++ b/core/fxge/skia/fx_skia_device.cpp
@@ -622,6 +622,7 @@ class SkiaState {
         m_drawText(false),
         m_drawPath(false),
         m_fillPath(false),
+        m_groupKnockout(false),
         m_debugDisable(false) {}
 
   bool DrawPath(const CFX_PathData* pPathData,
@@ -638,8 +639,9 @@ class SkiaState {
       FlushCommands(pDriver);
     if (m_drawText)
       FlushText(pDriver);
-    if (m_drawPath && DrawChanged(pMatrix, pDrawState, fill_color, stroke_color,
-                                  fill_mode, blend_type)) {
+    if (m_drawPath &&
+        DrawChanged(pMatrix, pDrawState, fill_color, stroke_color, fill_mode,
+                    blend_type, pDriver->m_bGroupKnockout)) {
       FlushPath(pDriver);
     }
     if (!m_drawPath) {
@@ -653,6 +655,7 @@ class SkiaState {
       m_fillColor = fill_color;
       m_strokeColor = stroke_color;
       m_blendType = blend_type;
+      m_groupKnockout = pDriver->m_bGroupKnockout;
       if (pMatrix)
         m_drawMatrix = *pMatrix;
     }
@@ -679,9 +682,7 @@ class SkiaState {
       SkPath strokePath;
       const SkPath* fillPath = &m_skPath;
       if (stroke_alpha) {
-        SkAlpha fillA = SkColorGetA(m_fillColor);
-        SkAlpha strokeA = SkColorGetA(m_strokeColor);
-        if (fillA && fillA < 0xFF && strokeA && strokeA < 0xFF) {
+        if (m_groupKnockout) {
           skPaint.getFillPath(m_skPath, &strokePath);
           if (Op(m_skPath, strokePath, SkPathOp::kDifference_SkPathOp,
                  &strokePath)) {
@@ -756,9 +757,9 @@ class SkiaState {
       skPaint.setTypeface(typeface);
     }
     skPaint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
-    skPaint.setTextSize(m_fontSize);
-    skPaint.setSubpixelText(true);
     skPaint.setHinting(SkPaint::kNo_Hinting);
+    skPaint.setTextSize(SkTAbs(m_fontSize));
+    skPaint.setSubpixelText(true);
     SkCanvas* skCanvas = pDriver->SkiaCanvas();
     skCanvas->save();
     skCanvas->concat(skMatrix);
@@ -898,13 +899,14 @@ class SkiaState {
                    uint32_t fill_color,
                    uint32_t stroke_color,
                    int fill_mode,
-                   int blend_type) {
+                   int blend_type,
+                   bool group_knockout) {
     return MatrixChanged(pMatrix, m_drawMatrix) ||
            StateChanged(pState, m_drawState) || fill_color != m_fillColor ||
            stroke_color != m_strokeColor ||
            ((fill_mode & 3) == FXFILL_ALTERNATE) !=
                (m_skPath.getFillType() == SkPath::kEvenOdd_FillType) ||
-           blend_type != m_blendType;
+           blend_type != m_blendType || group_knockout != m_groupKnockout;
   }
 
   bool FontChanged(CFX_Font* pFont,
@@ -1003,6 +1005,7 @@ class SkiaState {
   bool m_drawText;
   bool m_drawPath;
   bool m_fillPath;
+  bool m_groupKnockout;
   bool m_debugDisable;  // turn off cache for debugging
 };
 #endif  // _SKIA_SUPPORT_
@@ -1153,7 +1156,7 @@ bool CFX_SkiaDeviceDriver::DrawDeviceText(int nChars,
   paint.setTypeface(typeface);
   paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
   paint.setHinting(SkPaint::kNo_Hinting);
-  paint.setTextSize(font_size);
+  paint.setTextSize(SkTAbs(font_size));
   paint.setSubpixelText(true);
   m_pCanvas->save();
   SkScalar flip = font_size < 0 ? -1 : 1;