Bug 1556556 - Miscellaneous fixes related to event coordinate transformations. r=tnikkel

Differential Revision: https://phabricator.services.mozilla.com/D69639

dom/base/nsContentUtils.cpp

@@ -115,6 +115,7 @@
 #include "mozilla/TextControlState.h"
 #include "mozilla/TextEditor.h"
 #include "mozilla/TextEvents.h"
+#include "mozilla/ViewportUtils.h"
 #include "nsArrayUtils.h"
 #include "nsAString.h"
 #include "nsAttrName.h"
@@ -7844,11 +7845,11 @@ int16_t nsContentUtils::GetButtonsFlagForButton(int32_t aButton) {
 LayoutDeviceIntPoint nsContentUtils::ToWidgetPoint(
     const CSSPoint& aPoint, const nsPoint& aOffset,
     nsPresContext* aPresContext) {
+  nsPoint layoutRelative = CSSPoint::ToAppUnits(aPoint) + aOffset;
+  nsPoint visualRelative =
+      ViewportUtils::LayoutToVisual(layoutRelative, aPresContext->PresShell());
   return LayoutDeviceIntPoint::FromAppUnitsRounded(
-      (CSSPoint::ToAppUnits(aPoint) + aOffset)
-          .ApplyResolution(nsLayoutUtils::GetCurrentAPZResolutionScale(
-              aPresContext->PresShell())),
-      aPresContext->AppUnitsPerDevPixel());
+      visualRelative, aPresContext->AppUnitsPerDevPixel());
 }
 
 nsView* nsContentUtils::GetViewToDispatchEvent(nsPresContext* aPresContext,

dom/events/Event.cpp

@@ -21,6 +21,7 @@
 #include "mozilla/PresShell.h"
 #include "mozilla/TextEvents.h"
 #include "mozilla/TouchEvents.h"
+#include "mozilla/ViewportUtils.h"
 #include "mozilla/dom/Document.h"
 #include "mozilla/dom/DocumentInlines.h"
 #include "mozilla/dom/Event.h"
@@ -549,9 +550,8 @@ CSSIntPoint Event::GetScreenCoords(nsPresContext* aPresContext,
       rounded,
       aPresContext->DeviceContext()->AppUnitsPerDevPixelAtUnitFullZoom());
 
-  if (PresShell* presShell = aPresContext->GetPresShell()) {
-    pt = pt.RemoveResolution(
-        nsLayoutUtils::GetCurrentAPZResolutionScale(presShell));
+  if (PresShell* shell = aPresContext->GetPresShell()) {
+    pt = ViewportUtils::VisualToLayout(pt, shell);
   }
 
   pt += LayoutDevicePixel::ToAppUnits(

dom/ipc/BrowserParent.cpp

@@ -2473,9 +2473,14 @@ LayoutDeviceIntPoint BrowserParent::GetChildProcessOffset() {
   // any events we send to the child, and reverse them for any screen
   // coordinates that we retrieve from the child.
 
+  // TODO: Once we take into account transforms here, set viewportType
+  // correctly. For now we use Visual as this means we don't apply
+  // the layout-to-visual transform in TranslateViewToWidget().
+  ViewportType viewportType = ViewportType::Visual;
+
   nsPoint pt = targetFrame->GetOffsetTo(rootFrame);
   return -nsLayoutUtils::TranslateViewToWidget(presContext, rootView, pt,
-                                               widget);
+                                               viewportType, widget);
 }
 
 LayoutDeviceIntPoint BrowserParent::GetClientOffset() {

layout/base/PositionedEventTargeting.cpp

@@ -529,7 +529,8 @@ nsIFrame* FindFrameTargetedByInputEvent(
     return target;
   }
   LayoutDeviceIntPoint widgetPoint = nsLayoutUtils::TranslateViewToWidget(
-      aRootFrame.mFrame->PresContext(), view, point, aEvent->mWidget);
+      aRootFrame.mFrame->PresContext(), view, point, aRootFrame.mViewportType,
+      aEvent->mWidget);
   if (widgetPoint.x != NS_UNCONSTRAINEDSIZE) {
     // If that succeeded, we update the point in the event
     aEvent->mRefPoint = widgetPoint;

layout/base/nsLayoutUtils.cpp

@@ -3108,16 +3108,19 @@ nsPoint nsLayoutUtils::TranslateWidgetToView(nsPresContext* aPresContext,
 
 LayoutDeviceIntPoint nsLayoutUtils::TranslateViewToWidget(
     nsPresContext* aPresContext, nsView* aView, nsPoint aPt,
-    nsIWidget* aWidget) {
+    ViewportType aViewportType, nsIWidget* aWidget) {
   nsPoint viewOffset;
   nsIWidget* viewWidget = aView->GetNearestWidget(&viewOffset);
   if (!viewWidget) {
     return LayoutDeviceIntPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
   }
 
-  nsPoint pt = (aPt + viewOffset)
-                   .ApplyResolution(
-                       GetCurrentAPZResolutionScale(aPresContext->PresShell()));
+  nsPoint pt = (aPt + viewOffset);
+  // The target coordinates are visual, so perform a layout-to-visual
+  // conversion if the incoming coordinates are layout.
+  if (aViewportType == ViewportType::Layout && aPresContext->GetPresShell()) {
+    pt = ViewportUtils::LayoutToVisual(pt, aPresContext->GetPresShell());
+  }
   LayoutDeviceIntPoint relativeToViewWidget(
       aPresContext->AppUnitsToDevPixels(pt.x),
       aPresContext->AppUnitsToDevPixels(pt.y));

layout/base/nsLayoutUtils.h

@@ -882,12 +882,13 @@ class nsLayoutUtils {
    * @param aPresContext the PresContext for the view
    * @param aView the view
    * @param aPt the point relative to the view
+   * @param aViewportType whether the point is in visual or layout coordinates
    * @param aWidget the widget to which returned coordinates are relative
    * @return the point in the view's coordinates
    */
   static mozilla::LayoutDeviceIntPoint TranslateViewToWidget(
       nsPresContext* aPresContext, nsView* aView, nsPoint aPt,
-      nsIWidget* aWidget);
+      ViewportType aViewportType, nsIWidget* aWidget);
 
   static mozilla::LayoutDeviceIntPoint WidgetToWidgetOffset(
       nsIWidget* aFromWidget, nsIWidget* aToWidget);