From 43dc286d72670967352ccf2c4d556d1cde7d07a3 Mon Sep 17 00:00:00 2001
From: Jeff Muizelaar <jrmuizel@gmail.com>
Date: Mon, 8 Apr 2019 22:37:26 +0000
Subject: [PATCH] Bug 1541920. Handle blend mode activeness properly. r=mstange

Differential Revision: https://phabricator.services.mozilla.com/D26364

--HG--
extra : moz-landing-system : lando
---
 gfx/layers/wr/WebRenderCommandBuilder.cpp         | 15 ++++++++++++---
 layout/reftests/css-blending/reftest.list         |  2 +-
 .../svg/active-transform-blend-mode-ref.html      |  8 ++++++++
 .../reftests/svg/active-transform-blend-mode.html |  8 ++++++++
 layout/reftests/svg/reftest.list                  |  1 +
 5 files changed, 30 insertions(+), 4 deletions(-)
 create mode 100644 layout/reftests/svg/active-transform-blend-mode-ref.html
 create mode 100644 layout/reftests/svg/active-transform-blend-mode.html

diff --git a/gfx/layers/wr/WebRenderCommandBuilder.cpp b/gfx/layers/wr/WebRenderCommandBuilder.cpp
index 657320d6ea2d..7e2895674342 100644
--- a/gfx/layers/wr/WebRenderCommandBuilder.cpp
+++ b/gfx/layers/wr/WebRenderCommandBuilder.cpp
@@ -1083,12 +1083,13 @@ class WebRenderGroupData : public WebRenderUserData {
 };
 
 static bool IsItemProbablyActive(nsDisplayItem* aItem,
-                                 nsDisplayListBuilder* aDisplayListBuilder);
+                                 nsDisplayListBuilder* aDisplayListBuilder,
+                                 bool aParentActive = true);
 
 static bool HasActiveChildren(const nsDisplayList& aList,
                               nsDisplayListBuilder* aDisplayListBuilder) {
   for (nsDisplayItem* i = aList.GetBottom(); i; i = i->GetAbove()) {
-    if (IsItemProbablyActive(i, aDisplayListBuilder)) {
+    if (IsItemProbablyActive(i, aDisplayListBuilder, false)) {
       return true;
     }
   }
@@ -1103,7 +1104,8 @@ static bool HasActiveChildren(const nsDisplayList& aList,
 // We can't easily use GetLayerState because it wants a bunch of layers related
 // information.
 static bool IsItemProbablyActive(nsDisplayItem* aItem,
-                                 nsDisplayListBuilder* aDisplayListBuilder) {
+                                 nsDisplayListBuilder* aDisplayListBuilder,
+                                 bool aParentActive) {
   switch (aItem->GetType()) {
     case DisplayItemType::TYPE_TRANSFORM: {
       nsDisplayTransform* transformItem =
@@ -1128,6 +1130,13 @@ static bool IsItemProbablyActive(nsDisplayItem* aItem,
     case DisplayItemType::TYPE_FOREIGN_OBJECT: {
       return true;
     }
+    case DisplayItemType::TYPE_BLEND_MODE: {
+      /* BLEND_MODE needs to be active if it might have a previous sibling
+       * that is active. We use the activeness of the parent as a rough
+       * proxy for this situation. */
+      return aParentActive || HasActiveChildren(*aItem->GetChildren(),
+                                                aDisplayListBuilder);
+    }
     case DisplayItemType::TYPE_WRAP_LIST:
     case DisplayItemType::TYPE_PERSPECTIVE: {
       if (aItem->GetChildren()) {
diff --git a/layout/reftests/css-blending/reftest.list b/layout/reftests/css-blending/reftest.list
index a2b04e309875..e49806fc085f 100644
--- a/layout/reftests/css-blending/reftest.list
+++ b/layout/reftests/css-blending/reftest.list
@@ -41,7 +41,7 @@ fuzzy-if(azureSkia||d2d||gtkWidget,0-1,0-40000) == background-blending-image-col
 fuzzy(0-65,0-53) == mix-blend-mode-952051.html mix-blend-mode-952051-ref.html
 
 fuzzy-if(d3d11,0-49,0-200) == mix-blend-mode-and-filter.html mix-blend-mode-and-filter-ref.html
-fuzzy-if(webrender,9-9,2531-2716) fuzzy-if(d3d11,0-1,0-5) == mix-blend-mode-and-filter.svg mix-blend-mode-and-filter-ref.svg
+fuzzy-if(d3d11,0-1,0-5) == mix-blend-mode-and-filter.svg mix-blend-mode-and-filter-ref.svg
 
 fuzzy(0-2,0-14400) == mix-blend-mode-child-of-blended-has-opacity.html mix-blend-mode-child-of-blended-has-opacity-ref.html
 
diff --git a/layout/reftests/svg/active-transform-blend-mode-ref.html b/layout/reftests/svg/active-transform-blend-mode-ref.html
new file mode 100644
index 000000000000..6bb1bee6e40f
--- /dev/null
+++ b/layout/reftests/svg/active-transform-blend-mode-ref.html
@@ -0,0 +1,8 @@
+<svg width=1000 height=1000>
+    <g style="transform: translateY(-2px) translateX(0px) translateZ(0px);">
+        <rect fill="#0000ff" height="93" width="32" x="100" y="163"></rect>
+    </g>
+    <g style="mix-blend-mode: multiply;">
+        <rect fill="#ff0000" height="93" width="32" x="100" y="161"></rect>
+    </g>
+</svg>
diff --git a/layout/reftests/svg/active-transform-blend-mode.html b/layout/reftests/svg/active-transform-blend-mode.html
new file mode 100644
index 000000000000..2ed8dc46462d
--- /dev/null
+++ b/layout/reftests/svg/active-transform-blend-mode.html
@@ -0,0 +1,8 @@
+<svg width=1000 height=1000>
+    <g style="transform: translateY(-2px) translateX(0px) translateZ(0px); will-change: transform;">
+        <rect fill="#0000ff" height="93" width="32" x="100" y="163"></rect>
+    </g>
+    <g style="mix-blend-mode: multiply;">
+        <rect fill="#ff0000" height="93" width="32" x="100" y="161"></rect>
+    </g>
+</svg>
diff --git a/layout/reftests/svg/reftest.list b/layout/reftests/svg/reftest.list
index 254637f90847..403311628e2c 100644
--- a/layout/reftests/svg/reftest.list
+++ b/layout/reftests/svg/reftest.list
@@ -53,6 +53,7 @@ fuzzy-if(skiaContent,0-1,0-1600) skip-if(Android) == blend-multiply.svg blend-mu
 #skip-if(Android) == blend-screen.svg blend-screen-ref.svg
 #skip-if(Android) == blend-soft-light.svg blend-soft-light-ref.svg
 skip == blend-difference-stacking.html blend-difference-stacking-ref.html # bug 1458353
+== active-transform-blend-mode.html active-transform-blend-mode-ref.html
 
 fuzzy(0-11,0-7155) == blur-inside-clipPath.svg blur-inside-clipPath-ref.svg