Bug 1816628 Part 2 - Make text-shadow react to stroke properties and fill opacity r=jfkthame

Differential Revision: https://phabricator.services.mozilla.com/D200436

layout/generic/nsTextFrame.cpp

@@ -226,6 +226,7 @@ struct nsTextFrame::DrawTextRunParams {
   float textStrokeWidth = 0.0f;
   bool drawSoftHyphen = false;
   bool hasTextShadow = false;
+  bool paintingShadows = false;
   DrawTextRunParams(gfxContext* aContext,
                     mozilla::gfx::PaletteCache& aPaletteCache)
       : context(aContext), paletteCache(aPaletteCache) {}
@@ -276,6 +277,7 @@ struct nsTextFrame::PaintShadowParams {
   Point framePt;
   Point textBaselinePt;
   gfxContext* context;
+  DrawPathCallbacks* callbacks = nullptr;
   nscolor foregroundColor = NS_RGBA(0, 0, 0, 0);
   const ClipEdges* clipEdges = nullptr;
   PropertyProvider* provider = nullptr;
@@ -5459,6 +5461,7 @@ struct nsTextFrame::PaintDecorationLineParams
   gfxFloat baselineOffset = 0.0f;
   DecorationType decorationType = DecorationType::Normal;
   DrawPathCallbacks* callbacks = nullptr;
+  bool paintingShadows = false;
 };
 
 void nsTextFrame::PaintDecorationLine(
@@ -5473,9 +5476,11 @@ void nsTextFrame::PaintDecorationLine(
   if (aParams.callbacks) {
     Rect path = nsCSSRendering::DecorationLineToPath(params);
     if (aParams.decorationType == DecorationType::Normal) {
-      aParams.callbacks->PaintDecorationLine(path, params.color);
+      aParams.callbacks->PaintDecorationLine(path, aParams.paintingShadows,
+                                             params.color);
     } else {
-      aParams.callbacks->PaintSelectionDecorationLine(path, params.color);
+      aParams.callbacks->PaintSelectionDecorationLine(
+          path, aParams.paintingShadows, params.color);
     }
   } else {
     nsCSSRendering::PaintDecorationLine(this, *aParams.context->GetDrawTarget(),
@@ -5937,6 +5942,7 @@ void nsTextFrame::PaintOneShadow(const PaintShadowParams& aParams,
   gfxFloat advanceWidth;
   nsTextPaintStyle textPaintStyle(this);
   DrawTextParams params(shadowContext, PresContext()->FontPaletteCache());
+  params.paintingShadows = true;
   params.advanceWidth = &advanceWidth;
   params.dirtyRect = aParams.dirtyRect;
   params.framePt = aParams.framePt + shadowGfxOffset;
@@ -5944,9 +5950,10 @@ void nsTextFrame::PaintOneShadow(const PaintShadowParams& aParams,
   params.textStyle = &textPaintStyle;
   params.textColor =
       aParams.context == shadowContext ? shadowColor : NS_RGB(0, 0, 0);
+  params.callbacks = aParams.callbacks;
   params.clipEdges = aParams.clipEdges;
   params.drawSoftHyphen = HasAnyStateBits(TEXT_HYPHEN_BREAK);
-  // Multi-color shadow is not allowed, so we use the same color of the text
+  // Multi-color shadow is not allowed, so we use the same color as the text
   // color.
   params.decorationOverrideColor = &params.textColor;
   params.fontPalette = StyleFont()->GetFontPaletteAtom();
@@ -6252,6 +6259,7 @@ bool nsTextFrame::PaintTextWithSelectionColors(
 
   PaintShadowParams shadowParams(aParams);
   shadowParams.provider = aParams.provider;
+  shadowParams.callbacks = aParams.callbacks;
   shadowParams.clipEdges = &aClipEdges;
 
   // Draw text
@@ -6814,6 +6822,7 @@ void nsTextFrame::PaintText(const PaintTextParams& aParams,
     shadowParams.textBaselinePt = textBaselinePt;
     shadowParams.leftSideOffset = snappedStartEdge;
     shadowParams.provider = &provider;
+    shadowParams.callbacks = aParams.callbacks;
     shadowParams.foregroundColor = foregroundColor;
     shadowParams.clipEdges = &clipEdges;
     PaintShadows(textStyle->mTextShadow.AsSpan(), shadowParams);
@@ -6853,7 +6862,8 @@ static void DrawTextRun(const gfxTextRun* aTextRun,
   params.callbacks = aParams.callbacks;
   params.hasTextShadow = aParams.hasTextShadow;
   if (aParams.callbacks) {
-    aParams.callbacks->NotifyBeforeText(aParams.textColor);
+    aParams.callbacks->NotifyBeforeText(aParams.paintingShadows,
+                                        aParams.textColor);
     params.drawMode = DrawMode::GLYPH_PATH;
     aTextRun->Draw(aRange, aTextBaselinePt, params);
     aParams.callbacks->NotifyAfterText();
@@ -6994,6 +7004,7 @@ void nsTextFrame::DrawTextRunAndDecorations(
   params.callbacks = aParams.callbacks;
   params.glyphRange = aParams.glyphRange;
   params.provider = aParams.provider;
+  params.paintingShadows = aParams.paintingShadows;
   // pt is the physical point where the decoration is to be drawn,
   // relative to the frame; one of its coordinates will be updated below.
   params.pt = Point(x / app, y / app);

layout/generic/nsTextFrame.h

@@ -513,20 +513,22 @@ class nsTextFrame : public nsIFrame {
      * Called before (for under/over-line) or after (for line-through) the text
      * is drawn to have a text decoration line drawn.
      */
-    virtual void PaintDecorationLine(Rect aPath, nscolor aColor) {}
+    virtual void PaintDecorationLine(Rect aPath, bool aPaintingShadows,
+                                     nscolor aColor) {}
 
     /**
      * Called after selected text is drawn to have a decoration line drawn over
      * the text. (All types of text decoration are drawn after the text when
      * text is selected.)
      */
-    virtual void PaintSelectionDecorationLine(Rect aPath, nscolor aColor) {}
+    virtual void PaintSelectionDecorationLine(Rect aPath, bool aPaintingShadows,
+                                              nscolor aColor) {}
 
     /**
      * Called just before any paths have been emitted to the gfxContext
      * for the glyphs of the frame's text.
      */
-    virtual void NotifyBeforeText(nscolor aColor) {}
+    virtual void NotifyBeforeText(bool aPaintingShadows, nscolor aColor) {}
 
     /**
      * Called just after all the paths have been emitted to the gfxContext

layout/svg/SVGTextFrame.cpp

@@ -2412,9 +2412,11 @@ class SVGTextDrawPathCallbacks final : public nsTextFrame::DrawPathCallbacks {
   void NotifySelectionBackgroundNeedsFill(const Rect& aBackgroundRect,
                                           nscolor aColor,
                                           DrawTarget& aDrawTarget) override;
-  void PaintDecorationLine(Rect aPath, nscolor aColor) override;
-  void PaintSelectionDecorationLine(Rect aPath, nscolor aColor) override;
-  void NotifyBeforeText(nscolor aColor) override;
+  void PaintDecorationLine(Rect aPath, bool aPaintingShadows,
+                           nscolor aColor) override;
+  void PaintSelectionDecorationLine(Rect aPath, bool aPaintingShadows,
+                                    nscolor aColor) override;
+  void NotifyBeforeText(bool aPaintingShadows, nscolor aColor) override;
   void NotifyGlyphPathEmitted() override;
   void NotifyAfterText() override;
 
@@ -2453,6 +2455,12 @@ class SVGTextDrawPathCallbacks final : public nsTextFrame::DrawPathCallbacks {
    */
   void StrokeGeometry();
 
+  /*
+   * Takes a colour and modifies it to account for opacity properties.
+   */
+  void ApplyOpacity(sRGBColor& aColor, const StyleSVGPaint& aPaint,
+                    const StyleSVGOpacity& aOpacity) const;
+
   SVGTextFrame* const mSVGTextFrame;
   gfxContext& mContext;
   nsTextFrame* const mFrame;
@@ -2466,6 +2474,11 @@ class SVGTextDrawPathCallbacks final : public nsTextFrame::DrawPathCallbacks {
    * painting selections or IME decorations.
    */
   nscolor mColor;
+
+  /**
+   * Whether we're painting text shadows.
+   */
+  bool mPaintingShadows;
 };
 
 void SVGTextDrawPathCallbacks::NotifySelectionBackgroundNeedsFill(
@@ -2486,8 +2499,10 @@ void SVGTextDrawPathCallbacks::NotifySelectionBackgroundNeedsFill(
   }
 }
 
-void SVGTextDrawPathCallbacks::NotifyBeforeText(nscolor aColor) {
+void SVGTextDrawPathCallbacks::NotifyBeforeText(bool aPaintingShadows,
+                                                nscolor aColor) {
   mColor = aColor;
+  mPaintingShadows = aPaintingShadows;
   SetupContext();
   mContext.NewPath();
 }
@@ -2499,8 +2514,11 @@ void SVGTextDrawPathCallbacks::NotifyGlyphPathEmitted() {
 
 void SVGTextDrawPathCallbacks::NotifyAfterText() { mContext.Restore(); }
 
-void SVGTextDrawPathCallbacks::PaintDecorationLine(Rect aPath, nscolor aColor) {
+void SVGTextDrawPathCallbacks::PaintDecorationLine(Rect aPath,
+                                                   bool aPaintingShadows,
+                                                   nscolor aColor) {
   mColor = aColor;
+  mPaintingShadows = aPaintingShadows;
   AntialiasMode aaMode =
       SVGUtils::ToAntialiasMode(mFrame->StyleText()->mTextRendering);
 
@@ -2513,14 +2531,15 @@ void SVGTextDrawPathCallbacks::PaintDecorationLine(Rect aPath, nscolor aColor) {
   mContext.Restore();
 }
 
-void SVGTextDrawPathCallbacks::PaintSelectionDecorationLine(Rect aPath,
-                                                            nscolor aColor) {
+void SVGTextDrawPathCallbacks::PaintSelectionDecorationLine(
+    Rect aPath, bool aPaintingShadows, nscolor aColor) {
   if (IsClipPathChild()) {
     // Don't paint selection decorations when in a clip path.
     return;
   }
 
   mColor = aColor;
+  mPaintingShadows = aPaintingShadows;
 
   mContext.Save();
   mContext.NewPath();
@@ -2560,6 +2579,17 @@ void SVGTextDrawPathCallbacks::HandleTextGeometry() {
   }
 }
 
+void SVGTextDrawPathCallbacks::ApplyOpacity(
+    sRGBColor& aColor, const StyleSVGPaint& aPaint,
+    const StyleSVGOpacity& aOpacity) const {
+  if (aPaint.kind.tag == StyleSVGPaintKind::Tag::Color) {
+    aColor.a *=
+        sRGBColor::FromABGR(aPaint.kind.AsColor().CalcColor(*mFrame->Style()))
+            .a;
+  }
+  aColor.a *= SVGUtils::GetOpacity(aOpacity, /*aContextPaint*/ nullptr);
+}
+
 void SVGTextDrawPathCallbacks::MakeFillPattern(GeneralPattern* aOutPattern) {
   if (mColor == NS_SAME_AS_FOREGROUND_COLOR ||
       mColor == NS_40PERCENT_FOREGROUND_COLOR) {
@@ -2571,7 +2601,12 @@ void SVGTextDrawPathCallbacks::MakeFillPattern(GeneralPattern* aOutPattern) {
     return;
   }
 
-  aOutPattern->InitColorPattern(ToDeviceColor(mColor));
+  sRGBColor color(sRGBColor::FromABGR(mColor));
+  if (mPaintingShadows) {
+    ApplyOpacity(color, mFrame->StyleSVG()->mFill,
+                 mFrame->StyleSVG()->mFillOpacity);
+  }
+  aOutPattern->InitColorPattern(ToDeviceColor(color));
 }
 
 void SVGTextDrawPathCallbacks::FillAndStrokeGeometry() {
@@ -2606,6 +2641,9 @@ void SVGTextDrawPathCallbacks::FillAndStrokeGeometry() {
 }
 
 void SVGTextDrawPathCallbacks::FillGeometry() {
+  if (mFrame->StyleSVG()->mFill.kind.IsNone()) {
+    return;
+  }
   GeneralPattern fillPattern;
   MakeFillPattern(&fillPattern);
   if (fillPattern.GetPattern()) {
@@ -2621,39 +2659,44 @@ void SVGTextDrawPathCallbacks::FillGeometry() {
 
 void SVGTextDrawPathCallbacks::StrokeGeometry() {
   // We don't paint the stroke when we are filling with a selection color.
-  if (mColor == NS_SAME_AS_FOREGROUND_COLOR ||
-      mColor == NS_40PERCENT_FOREGROUND_COLOR) {
-    if (SVGUtils::HasStroke(mFrame, /*aContextPaint*/ nullptr)) {
-      GeneralPattern strokePattern;
-      SVGUtils::MakeStrokePatternFor(mFrame, &mContext, &strokePattern,
-                                     mImgParams, /*aContextPaint*/ nullptr);
-      if (strokePattern.GetPattern()) {
-        if (!mFrame->GetParent()->GetContent()->IsSVGElement()) {
-          // The cast that follows would be unsafe
-          MOZ_ASSERT(false, "Our nsTextFrame's parent's content should be SVG");
-          return;
-        }
-        SVGElement* svgOwner =
-            static_cast<SVGElement*>(mFrame->GetParent()->GetContent());
+  if (!(mColor == NS_SAME_AS_FOREGROUND_COLOR ||
+        mColor == NS_40PERCENT_FOREGROUND_COLOR || mPaintingShadows)) {
+    return;
+  }
 
-        // Apply any stroke-specific transform
-        gfxMatrix outerSVGToUser;
-        if (SVGUtils::GetNonScalingStrokeTransform(mFrame, &outerSVGToUser) &&
-            outerSVGToUser.Invert()) {
-          mContext.Multiply(outerSVGToUser);
-        }
+  if (!SVGUtils::HasStroke(mFrame, /*aContextPaint*/ nullptr)) {
+    return;
+  }
 
-        RefPtr<Path> path = mContext.GetPath();
-        SVGContentUtils::AutoStrokeOptions strokeOptions;
-        SVGContentUtils::GetStrokeOptions(&strokeOptions, svgOwner,
-                                          mFrame->Style(),
-                                          /*aContextPaint*/ nullptr);
-        DrawOptions drawOptions;
-        drawOptions.mAntialiasMode =
-            SVGUtils::ToAntialiasMode(mFrame->StyleText()->mTextRendering);
-        mContext.GetDrawTarget()->Stroke(path, strokePattern, strokeOptions);
-      }
+  GeneralPattern strokePattern;
+  if (mPaintingShadows) {
+    sRGBColor color(sRGBColor::FromABGR(mColor));
+    ApplyOpacity(color, mFrame->StyleSVG()->mStroke,
+                 mFrame->StyleSVG()->mStrokeOpacity);
+    strokePattern.InitColorPattern(ToDeviceColor(color));
+  } else {
+    SVGUtils::MakeStrokePatternFor(mFrame, &mContext, &strokePattern,
+                                   mImgParams, /*aContextPaint*/ nullptr);
+  }
+  if (strokePattern.GetPattern()) {
+    SVGElement* svgOwner =
+        SVGElement::FromNode(mFrame->GetParent()->GetContent());
+
+    // Apply any stroke-specific transform
+    gfxMatrix outerSVGToUser;
+    if (SVGUtils::GetNonScalingStrokeTransform(mFrame, &outerSVGToUser) &&
+        outerSVGToUser.Invert()) {
+      mContext.Multiply(outerSVGToUser);
     }
+
+    RefPtr<Path> path = mContext.GetPath();
+    SVGContentUtils::AutoStrokeOptions strokeOptions;
+    SVGContentUtils::GetStrokeOptions(&strokeOptions, svgOwner, mFrame->Style(),
+                                      /*aContextPaint*/ nullptr);
+    DrawOptions drawOptions;
+    drawOptions.mAntialiasMode =
+        SVGUtils::ToAntialiasMode(mFrame->StyleText()->mTextRendering);
+    mContext.GetDrawTarget()->Stroke(path, strokePattern, strokeOptions);
   }
 }
 
@@ -4910,11 +4953,20 @@ bool SVGTextFrame::ShouldRenderAsPath(nsTextFrame* aFrame,
 
   const nsStyleSVG* style = aFrame->StyleSVG();
 
-  // Fill is a non-solid paint, has a non-default fill-rule or has
-  // non-1 opacity.
+  // Fill is a non-solid paint or is not opaque.
   if (!(style->mFill.kind.IsNone() ||
-        (style->mFill.kind.IsColor() && style->mFillOpacity.IsOpacity() &&
-         style->mFillOpacity.AsOpacity() == 1))) {
+        (style->mFill.kind.IsColor() &&
+         SVGUtils::GetOpacity(style->mFillOpacity, /*aContextPaint*/ nullptr) ==
+             1.0f))) {
+    return true;
+  }
+
+  // If we're going to need to draw a non-opaque shadow.
+  // It's possible nsTextFrame will support non-opaque shadows in the future,
+  // in which case this test can be removed.
+  if (style->mFill.kind.IsColor() && aFrame->StyleText()->HasTextShadow() &&
+      NS_GET_A(style->mFill.kind.AsColor().CalcColor(*aFrame->Style())) !=
+          0xFF) {
     return true;
   }
 

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-fill-none-ref.html

@@ -0,0 +1,8 @@
+<!doctype html>
+<style>
+svg { font: bold 64px Arial, sans-serif; fill: none; stroke-width: 4px; }
+</style>
+<svg width="240" height="80">
+  <text x="40" y="60" stroke="grey">Hello</text>
+  <text x="30" y="50" stroke="black">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-fill-none.html

@@ -0,0 +1,10 @@
+<!doctype html>
+<title>CSS Test: 'text-shadow' respects 'fill="none"'</title>
+<link rel="help" href="https://www.w3.org/TR/css-text-decor-3/#text-shadow-property">
+<link rel="match" href="svg-fill-none-ref.html">
+<style>
+svg { font: bold 64px Arial, sans-serif; text-shadow: grey 10px 10px }
+</style>
+<svg width="240" height="80">
+  <text x="30" y="50" fill="none" stroke="black" stroke-width="4">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-fill-opacity-ref.html

@@ -0,0 +1,7 @@
+<!doctype html>
+<style>
+svg { font: bold 64px Arial, sans-serif; text-shadow: grey 10px 10px }
+</style>
+<svg width="240" height="80">
+  <text x="30" y="50" fill-opacity="0.5" fill="#FFFF00">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-fill-opacity.html

@@ -0,0 +1,10 @@
+<!doctype html>
+<title>CSS Test: 'text-shadow' respects non-opaque fill</title>
+<link rel="help" href="https://www.w3.org/TR/css-text-decor-3/#text-shadow-property">
+<link rel="match" href="svg-fill-opacity-ref.html">
+<style>
+svg { font: bold 64px Arial, sans-serif; text-shadow: grey 10px 10px }
+</style>
+<svg width="240" height="80">
+  <text x="30" y="50" fill="rgba(255, 255, 0, 0.5)">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-stroke-dasharray-ref.html

@@ -0,0 +1,8 @@
+<!doctype html>
+<style>
+svg { font: bold 64px Arial, sans-serif; fill: none; stroke-width: 2px; stroke-dasharray:2, 2; }
+</style>
+<svg width="240" height="80">
+  <text x="40" y="60" stroke="grey">Hello</text>
+  <text x="30" y="50" stroke="black">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-stroke-dasharray.html

@@ -0,0 +1,10 @@
+<!doctype html>
+<title>CSS Test: 'text-shadow' respects stroke-dasharray</title>
+<link rel="help" href="https://www.w3.org/TR/css-text-decor-3/#text-shadow-property">
+<link rel="match" href="svg-stroke-dasharray-ref.html">
+<style>
+svg { font: bold 64px Arial, sans-serif; text-shadow: grey 10px 10px }
+</style>
+<svg width="240" height="80">
+  <text x="30" y="50" fill="none" stroke="black" stroke-width="2" stroke-dasharray="2, 2">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-stroke-ref.html

@@ -0,0 +1,8 @@
+<!doctype html>
+<style>
+svg { font: bold 64px Arial, sans-serif; stroke: black; stroke-width: 4px; }
+</style>
+<svg width="240" height="80">
+  <text x="40" y="60" fill="grey" stroke="grey">Hello</text>
+  <text x="30" y="50">Hello</text>
+</svg>

testing/web-platform/tests/css/css-text-decor/text-shadow/svg-stroke.html

@@ -0,0 +1,10 @@
+<!doctype html>
+<title>CSS Test: 'text-shadow' respects stroke</title>
+<link rel="help" href="https://www.w3.org/TR/css-text-decor-3/#text-shadow-property">
+<link rel="match" href="svg-stroke-ref.html">
+<style>
+svg { font: bold 64px Arial, sans-serif; text-shadow: grey 10px 10px }
+</style>
+<svg width="240" height="80">
+  <text x="30" y="50" stroke="black" stroke-width="4">Hello</text>
+</svg>