From 1d1646afd1ff4f068fc41d8b142b08d53e6cd91a Mon Sep 17 00:00:00 2001
From: zhongwuzw <zhongwuzw@qq.com>
Date: Fri, 16 Aug 2024 01:00:07 -0700
Subject: [PATCH] Fixes findNodeAtPoint when views were inverted (#45519)

Summary:
FIxes https://github.com/facebook/react-native/issues/45502 .  cc realsoelynn

## Changelog:

[GENERAL] [FIXED] - Fixes findNodeAtPoint when views were inverted

Pull Request resolved: https://github.com/facebook/react-native/pull/45519

Test Plan: Demo in https://github.com/facebook/react-native/issues/45502 .

Reviewed By: cipolleschi

Differential Revision: D59920660

Pulled By: realsoelynn

fbshipit-source-id: 9e1075406830aa3a3ec436d70d539ca0674f8d34
---
 .../renderer/core/LayoutableShadowNode.cpp    | 24 ++++++++-
 .../core/tests/FindNodeAtPointTest.cpp        | 49 +++++++++++++++++++
 .../react/renderer/graphics/Transform.cpp     |  5 +-
 3 files changed, 75 insertions(+), 3 deletions(-)

diff --git a/packages/react-native/ReactCommon/react/renderer/core/LayoutableShadowNode.cpp b/packages/react-native/ReactCommon/react/renderer/core/LayoutableShadowNode.cpp
index a5f56b4ea9c..8aee6ef9953 100644
--- a/packages/react-native/ReactCommon/react/renderer/core/LayoutableShadowNode.cpp
+++ b/packages/react-native/ReactCommon/react/renderer/core/LayoutableShadowNode.cpp
@@ -261,8 +261,9 @@ ShadowNode::Shared LayoutableShadowNode::findNodeAtPoint(
     return nullptr;
   }
 
+  auto transform = layoutableShadowNode->getTransform();
   auto frame = layoutableShadowNode->getLayoutMetrics().frame;
-  auto transformedFrame = frame * layoutableShadowNode->getTransform();
+  auto transformedFrame = frame * transform;
   auto isPointInside = transformedFrame.containsPoint(point);
 
   if (!isPointInside) {
@@ -271,6 +272,27 @@ ShadowNode::Shared LayoutableShadowNode::findNodeAtPoint(
     return node;
   }
 
+  if (Transform::isVerticalInversion(transform) ||
+      Transform::isHorizontalInversion(transform)) {
+    auto centerX =
+        transformedFrame.origin.x + transformedFrame.size.width / 2.0;
+    auto centerY =
+        transformedFrame.origin.y + transformedFrame.size.height / 2.0;
+
+    auto relativeX = point.x - centerX;
+    auto relativeY = point.y - centerY;
+
+    if (Transform::isVerticalInversion(transform)) {
+      relativeY = -relativeY;
+    }
+    if (Transform::isHorizontalInversion(transform)) {
+      relativeX = -relativeX;
+    }
+
+    point.x = centerX + relativeX;
+    point.y = centerY + relativeY;
+  }
+
   auto newPoint = point - transformedFrame.origin -
       layoutableShadowNode->getContentOriginOffset(false);
 
diff --git a/packages/react-native/ReactCommon/react/renderer/core/tests/FindNodeAtPointTest.cpp b/packages/react-native/ReactCommon/react/renderer/core/tests/FindNodeAtPointTest.cpp
index 0b95fc5443b..c167f86591a 100644
--- a/packages/react-native/ReactCommon/react/renderer/core/tests/FindNodeAtPointTest.cpp
+++ b/packages/react-native/ReactCommon/react/renderer/core/tests/FindNodeAtPointTest.cpp
@@ -366,3 +366,52 @@ TEST(FindNodeAtPointTest, overlappingViewsWithParentPointerEventsNone) {
   EXPECT_EQ(
             LayoutableShadowNode::findNodeAtPoint(parentShadowNode, {50, 50}), nullptr);
 }
+
+TEST(FindNodeAtPointTest, invertedList) {
+  auto builder = simpleComponentBuilder();
+  
+  // clang-format off
+  auto element =
+    Element<ScrollViewShadowNode>()
+      .props([] {
+        auto sharedProps = std::make_shared<ScrollViewProps>();
+        sharedProps->transform = Transform::VerticalInversion();
+        return sharedProps;
+      })
+      .tag(1)
+      .finalize([](ScrollViewShadowNode &shadowNode){
+        auto layoutMetrics = EmptyLayoutMetrics;
+        layoutMetrics.frame.size = {100, 200};
+        shadowNode.setLayoutMetrics(layoutMetrics);
+      })
+      .children({
+        Element<ViewShadowNode>()
+        .tag(2)
+        .finalize([](ViewShadowNode &shadowNode){
+          auto layoutMetrics = EmptyLayoutMetrics;
+          layoutMetrics.frame.origin = {0, 0};
+          layoutMetrics.frame.size = {100, 100};
+          shadowNode.setLayoutMetrics(layoutMetrics);
+        }),
+        Element<ViewShadowNode>()
+        .tag(3)
+        .finalize([](ViewShadowNode &shadowNode){
+          auto layoutMetrics = EmptyLayoutMetrics;
+          layoutMetrics.frame.origin = {0, 100};
+          layoutMetrics.frame.size = {100, 100};
+          shadowNode.setLayoutMetrics(layoutMetrics);
+        })
+    });
+  // clang-format on
+
+  auto parentShadowNode = builder.build(element);
+
+  EXPECT_EQ(
+      LayoutableShadowNode::findNodeAtPoint(parentShadowNode, {10, 10})
+          ->getTag(),
+      3);
+  EXPECT_EQ(
+      LayoutableShadowNode::findNodeAtPoint(parentShadowNode, {10, 105})
+          ->getTag(),
+      2);
+}
diff --git a/packages/react-native/ReactCommon/react/renderer/graphics/Transform.cpp b/packages/react-native/ReactCommon/react/renderer/graphics/Transform.cpp
index d65299a25d3..1fe176f0cbc 100644
--- a/packages/react-native/ReactCommon/react/renderer/graphics/Transform.cpp
+++ b/packages/react-native/ReactCommon/react/renderer/graphics/Transform.cpp
@@ -11,6 +11,7 @@
 
 #include <glog/logging.h>
 #include <react/debug/react_native_assert.h>
+#include <react/utils/FloatComparison.h>
 
 namespace facebook::react {
 
@@ -305,11 +306,11 @@ Transform Transform::Interpolate(
 }
 
 bool Transform::isVerticalInversion(const Transform& transform) {
-  return transform.at(1, 1) == -1;
+  return facebook::react::floatEquality(transform.at(1, 1), -1.0f);
 }
 
 bool Transform::isHorizontalInversion(const Transform& transform) {
-  return transform.at(0, 0) == -1;
+  return facebook::react::floatEquality(transform.at(0, 0), -1.0f);
 }
 
 bool Transform::operator==(const Transform& rhs) const {