From 83b27417ae6a1d577b1fddfa3c9433c2dc42a460 Mon Sep 17 00:00:00 2001
From: Sidharth Guglani <sidharthguglani@fb.com>
Date: Mon, 27 Apr 2020 14:38:51 -0700
Subject: [PATCH] Fix rounding error using double instead of float

Summary: Changelog: [Internal] [Yoga] Use double instead of float during rounding process to prevent loss of precision.

Reviewed By: mdvacca

Differential Revision: D21227565

fbshipit-source-id: 380b57535a356624cda8dc2017871a4ef3c882d1
---
 yoga/Yoga.cpp | 26 +++++++++++++-------------
 yoga/Yoga.h   |  4 ++--
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/yoga/Yoga.cpp b/yoga/Yoga.cpp
index bb7da7bf..c2a5c286 100644
--- a/yoga/Yoga.cpp
+++ b/yoga/Yoga.cpp
@@ -3664,8 +3664,8 @@ static inline bool YGMeasureModeNewMeasureSizeIsStricterAndStillValid(
 }
 
 YOGA_EXPORT float YGRoundValueToPixelGrid(
-    const float value,
-    const float pointScaleFactor,
+    const double value,
+    const double pointScaleFactor,
     const bool forceCeil,
     const bool forceFloor) {
   double scaledValue = ((double) value) * pointScaleFactor;
@@ -4081,24 +4081,24 @@ YOGA_EXPORT void YGConfigSetPointScaleFactor(
 
 static void YGRoundToPixelGrid(
     const YGNodeRef node,
-    const float pointScaleFactor,
-    const float absoluteLeft,
-    const float absoluteTop) {
+    const double pointScaleFactor,
+    const double absoluteLeft,
+    const double absoluteTop) {
   if (pointScaleFactor == 0.0f) {
     return;
   }
 
-  const float nodeLeft = node->getLayout().position[YGEdgeLeft];
-  const float nodeTop = node->getLayout().position[YGEdgeTop];
+  const double nodeLeft = node->getLayout().position[YGEdgeLeft];
+  const double nodeTop = node->getLayout().position[YGEdgeTop];
 
-  const float nodeWidth = node->getLayout().dimensions[YGDimensionWidth];
-  const float nodeHeight = node->getLayout().dimensions[YGDimensionHeight];
+  const double nodeWidth = node->getLayout().dimensions[YGDimensionWidth];
+  const double nodeHeight = node->getLayout().dimensions[YGDimensionHeight];
 
-  const float absoluteNodeLeft = absoluteLeft + nodeLeft;
-  const float absoluteNodeTop = absoluteTop + nodeTop;
+  const double absoluteNodeLeft = absoluteLeft + nodeLeft;
+  const double absoluteNodeTop = absoluteTop + nodeTop;
 
-  const float absoluteNodeRight = absoluteNodeLeft + nodeWidth;
-  const float absoluteNodeBottom = absoluteNodeTop + nodeHeight;
+  const double absoluteNodeRight = absoluteNodeLeft + nodeWidth;
+  const double absoluteNodeBottom = absoluteNodeTop + nodeHeight;
 
   // If a node has a custom measure function we never want to round down its
   // size as this could lead to unwanted text truncation.
diff --git a/yoga/Yoga.h b/yoga/Yoga.h
index 2fe60a41..87901a28 100644
--- a/yoga/Yoga.h
+++ b/yoga/Yoga.h
@@ -352,8 +352,8 @@ WIN_EXPORT void YGConfigSetContext(YGConfigRef config, void* context);
 WIN_EXPORT void* YGConfigGetContext(YGConfigRef config);
 
 WIN_EXPORT float YGRoundValueToPixelGrid(
-    float value,
-    float pointScaleFactor,
+    double value,
+    double pointScaleFactor,
     bool forceCeil,
     bool forceFloor);