Bug 1444185 - More consistently round around fallback data. r=mstange

To avoid trimming pixels at the top / left.

This makes it closer to non-WR[1], and fixes both the checkboxes getting
cut off and the master password field.

[1]: non-WR at least at 124 scaling on a hiDPI display is still perfect, though I saw nin symmetric borders at other resolutions, so we might be able to improve here further.

Differential Revision: https://phabricator.services.mozilla.com/D7251

--HG--
extra : moz-landing-system : lando

gfx/layers/wr/WebRenderCommandBuilder.cpp

@@ -1709,7 +1709,6 @@ PaintByLayer(nsDisplayItem* aItem,
 static bool
 PaintItemByDrawTarget(nsDisplayItem* aItem,
                       gfx::DrawTarget* aDT,
-                      const LayerRect& aImageRect,
                       const LayoutDevicePoint& aOffset,
                       nsDisplayListBuilder* aDisplayListBuilder,
                       const RefPtr<BasicLayerManager>& aManager,
@@ -1719,7 +1718,8 @@ PaintItemByDrawTarget(nsDisplayItem* aItem,
   MOZ_ASSERT(aDT);
 
   bool isInvalidated = false;
-  aDT->ClearRect(aImageRect.ToUnknownRect());
+  // XXX Why is this ClearRect() needed?
+  aDT->ClearRect(Rect(aDT->GetRect()));
   RefPtr<gfxContext> context = gfxContext::CreateOrNull(aDT);
   MOZ_ASSERT(context);
 
@@ -1764,14 +1764,14 @@ PaintItemByDrawTarget(nsDisplayItem* aItem,
     // which isn't very useful.
     if (aHighlight) {
       aDT->SetTransform(gfx::Matrix());
-      aDT->FillRect(gfx::Rect(0, 0, aImageRect.Width(), aImageRect.Height()), gfx::ColorPattern(aHighlight.value()));
+      aDT->FillRect(Rect(aDT->GetRect()), gfx::ColorPattern(aHighlight.value()));
     }
     if (aItem->Frame()->PresContext()->GetPaintFlashing() && isInvalidated) {
       aDT->SetTransform(gfx::Matrix());
       float r = float(rand()) / RAND_MAX;
       float g = float(rand()) / RAND_MAX;
       float b = float(rand()) / RAND_MAX;
-      aDT->FillRect(gfx::Rect(0, 0, aImageRect.Width(), aImageRect.Height()), gfx::ColorPattern(gfx::Color(r, g, b, 0.5)));
+      aDT->FillRect(Rect(aDT->GetRect()), gfx::ColorPattern(gfx::Color(r, g, b, 0.5)));
     }
   }
 
@@ -1819,7 +1819,10 @@ WebRenderCommandBuilder::GenerateFallbackData(nsDisplayItem* aItem,
   aItem->ComputeVisibility(aDisplayListBuilder, &visibleRegion);
 
   const int32_t appUnitsPerDevPixel = aItem->Frame()->PresContext()->AppUnitsPerDevPixel();
-  LayoutDeviceRect bounds = LayoutDeviceRect::FromAppUnits(paintBounds, appUnitsPerDevPixel);
+  auto bounds = LayoutDeviceRect::FromAppUnits(paintBounds, appUnitsPerDevPixel);
+  if (bounds.IsEmpty()) {
+    return nullptr;
+  }
 
   gfx::Size scale = aSc.GetInheritedScale();
   gfx::Size oldScale = fallbackData->GetScale();
@@ -1830,31 +1833,18 @@ WebRenderCommandBuilder::GenerateFallbackData(nsDisplayItem* aItem,
   bool differentScale = gfx::FuzzyEqual(scale.width, oldScale.width, 1e-6f) &&
                         gfx::FuzzyEqual(scale.height, oldScale.height, 1e-6f);
 
-  // XXX not sure if paintSize should be in layer or layoutdevice pixels, it
-  // has some sort of scaling applied.
-  LayerIntSize paintSize = RoundedToInt(LayerSize(bounds.Width() * scale.width, bounds.Height() * scale.height));
-  if (paintSize.width == 0 || paintSize.height == 0) {
-    return nullptr;
-  }
+  LayoutDeviceToLayerScale2D layerScale(scale.width, scale.height);
+  auto scaledBounds = bounds * layerScale;
+  auto dtRect = RoundedOut(scaledBounds);
+  auto dtSize = dtRect.Size();
 
-  // Some display item may draw exceed the paintSize, we need prepare a larger
-  // draw target to contain the result.
-  auto scaledBounds = bounds * LayoutDeviceToLayerScale(1);
-  scaledBounds.Scale(scale.width, scale.height);
-  LayerIntSize dtSize = RoundedToInt(scaledBounds).Size();
+  aImageRect = dtRect / layerScale;
 
-  // TODO Rounding a rect to integers and then taking the size gives a different behavior than
-  // just rounding the size of the rect to integers. This can cause a crash, but fixing the
-  // difference causes some test failures so this is a quick fix
-  if (dtSize.width <= 0 || dtSize.height <= 0) {
-    return nullptr;
-  }
+  auto offset = aImageRect.TopLeft();
+
+  nsDisplayItemGeometry* geometry = fallbackData->GetGeometry();
 
   bool needPaint = true;
-  LayoutDeviceIntPoint offset = RoundedToInt(bounds.TopLeft());
-  aImageRect = LayoutDeviceRect(offset, LayoutDeviceSize(RoundedToInt(bounds).Size()));
-  LayerRect paintRect = LayerRect(LayerPoint(0, 0), LayerSize(paintSize));
-  nsDisplayItemGeometry* geometry = fallbackData->GetGeometry();
 
   // nsDisplayFilters is rendered via BasicLayerManager which means the invalidate
   // region is unknown until we traverse the displaylist contained by it.
@@ -1918,9 +1908,9 @@ WebRenderCommandBuilder::GenerateFallbackData(nsDisplayItem* aItem,
       if (!fallbackData->mBasicLayerManager) {
         fallbackData->mBasicLayerManager = new BasicLayerManager(BasicLayerManager::BLM_INACTIVE);
       }
-      bool isInvalidated = PaintItemByDrawTarget(aItem, dt, paintRect, offset, aDisplayListBuilder,
+      bool isInvalidated = PaintItemByDrawTarget(aItem, dt, offset, aDisplayListBuilder,
                                                  fallbackData->mBasicLayerManager, scale, highlight);
-      recorder->FlushItem(IntRect(0, 0, paintSize.width, paintSize.height));
+      recorder->FlushItem(IntRect({ 0, 0 }, dtSize.ToUnknownSize()));
       TakeExternalSurfaces(recorder, fallbackData->mExternalSurfaces, mManager, aResources);
       recorder->Finish();
 
@@ -1956,7 +1946,7 @@ WebRenderCommandBuilder::GenerateFallbackData(nsDisplayItem* aItem,
           if (!fallbackData->mBasicLayerManager) {
             fallbackData->mBasicLayerManager = new BasicLayerManager(mManager->GetWidget());
           }
-          isInvalidated = PaintItemByDrawTarget(aItem, dt, paintRect, offset,
+          isInvalidated = PaintItemByDrawTarget(aItem, dt, offset,
                                                 aDisplayListBuilder,
                                                 fallbackData->mBasicLayerManager, scale,
                                                 highlight);
@@ -2014,7 +2004,7 @@ WebRenderCommandBuilder::BuildWrMaskImage(nsDisplayItem* aItem,
 
   wr::WrImageMask imageMask;
   imageMask.image = fallbackData->GetKey().value();
-  imageMask.rect = wr::ToRoundedLayoutRect(aBounds);
+  imageMask.rect = wr::ToRoundedLayoutRect(imageRect);
   imageMask.repeat = false;
   return Some(imageMask);
 }

layout/reftests/border-image/reftest.list

@@ -12,7 +12,7 @@ fuzzy-if(winWidget,0-1,0-1) == multicolor-image-2.html multicolor-image-2-ref.ht
 == transparent-image-1.html transparent-image-1-ref.html
 != repeat-image-1.html repeat-image-1-ref.html
 fuzzy-if(webrender,15-15,975-986) == 470250-1.html 470250-1-ref.html
-fuzzy-if(webrender,15-15,975-986) == 470250-2.html 470250-2-ref.html
+fuzzy-if(webrender,15-233,975-1073) == 470250-2.html 470250-2-ref.html
 != different-h-v-1.html different-h-v-ref.html
 != different-h-v-2.html different-h-v-ref.html
 != different-h-v-1.html different-h-v-2.html

layout/reftests/bugs/reftest.list

@@ -1420,8 +1420,8 @@ fuzzy-if(Android,0-5,0-1656) fuzzy-if(skiaContent,0-1,0-1200) == 512410.html 512
 == 512631-1.html 512631-1-ref.html
 == 513153-1a.html 513153-1-ref.html
 == 513153-1b.html 513153-1-ref.html
-== 513153-2a.html 513153-2-ref.html
-fuzzy-if(webrender&&cocoaWidget,5-5,106-106) == 513153-2b.html 513153-2-ref.html
+fuzzy-if(webrender&&winWidget,82-82,76-76) == 513153-2a.html 513153-2-ref.html
+fuzzy-if(webrender&&cocoaWidget,34-34,103-103) == 513153-2b.html 513153-2-ref.html
 == 513318-1.xul 513318-1-ref.xul
 fails-if(Android&&(!asyncPan)) != 513318-2.xul 513318-2-ref.xul
 == 514917-1.html 514917-1-ref.html

layout/reftests/forms/input/range/reftest.list

@@ -14,13 +14,13 @@ fuzzy-if(skiaContent,0-1,0-40) == to-range-from-other-type-unthemed-1.html to-ra
 
 # dynamic value changes:
 fuzzy-if(skiaContent,0-1,0-40) == value-prop-unthemed.html 75pct-unthemed-common-ref.html
-== value-prop.html 75pct-common-ref.html
+fuzzy-if(webrender&&gtkWidget,96-96,163-163) == value-prop.html 75pct-common-ref.html
 fuzzy-if(skiaContent,0-1,0-40) == valueAsNumber-prop-unthemed.html 75pct-unthemed-common-ref.html
-== valueAsNumber-prop.html 75pct-common-ref.html
+fuzzy-if(webrender&&gtkWidget,96-96,163-163) == valueAsNumber-prop.html 75pct-common-ref.html
 fuzzy-if(skiaContent,0-1,0-40) == stepDown-unthemed.html 75pct-unthemed-common-ref.html
-== stepDown.html 75pct-common-ref.html
+fuzzy-if(webrender&&gtkWidget,96-96,163-163) == stepDown.html 75pct-common-ref.html
 fuzzy-if(skiaContent,0-1,0-40) == stepUp-unthemed.html 75pct-unthemed-common-ref.html
-== stepUp.html 75pct-common-ref.html
+fuzzy-if(webrender&&gtkWidget,96-96,163-163) == stepUp.html 75pct-common-ref.html
 == max-prop.html 100pct-common-ref.html
 == reset-value.html reset-value-ref.html
 

layout/reftests/mathml/reftest.list

@@ -374,7 +374,7 @@ test-pref(font.minimum-size.x-math,40) == default-font.html default-font-ref.htm
 != radicalbar-1a.html about:blank
 != radicalbar-1b.html about:blank
 != radicalbar-1c.html about:blank
-fails-if(webrender&&gtkWidget) != radicalbar-1d.html about:blank
+!= radicalbar-1d.html about:blank
 != radicalbar-2.html about:blank
 != radicalbar-2a.html about:blank
 != radicalbar-2b.html about:blank

layout/reftests/text-overflow/reftest.list

@@ -3,7 +3,7 @@
 fuzzy-if(Android,0-16,0-244) fuzzy-if(webrender,0-47,0-6) == marker-basic.html marker-basic-ref.html  # Bug 1128229
 == marker-string.html marker-string-ref.html
 skip-if(Android) fuzzy-if(webrender,0-47,0-18) == bidi-simple.html bidi-simple-ref.html # Fails on Android due to anti-aliasing
-skip-if(!gtkWidget) fuzzy-if(gtkWidget,0-2,0-289) == bidi-simple-scrolled.html bidi-simple-scrolled-ref.html # Fails on Windows and OSX due to anti-aliasing
+skip-if(!gtkWidget) fuzzy-if(gtkWidget,0-124,0-289) == bidi-simple-scrolled.html bidi-simple-scrolled-ref.html # Fails on Windows and OSX due to anti-aliasing
 fuzzy-if(Android,0-24,0-4000) fuzzy-if(cocoaWidget,0-1,0-40) fuzzy-if(asyncPan&&!layersGPUAccelerated,0-149,0-1836) == scroll-rounding.html scroll-rounding-ref.html # bug 760264
 fuzzy(0-16,0-454) fails-if(gtkWidget) fuzzy-if(webrender&&!gtkWidget,50-85,459-499) skip-if(OSX&&!isDebugBuild&&verify) == anonymous-block.html anonymous-block-ref.html # gtkWidget:bug 1309103, fuzzy: subpixel aa
 fuzzy-if(webrender,0-47,0-3) == false-marker-overlap.html false-marker-overlap-ref.html