From 1e5bbc63baf619a2f6e5c66b9d081d9cf08e2edc Mon Sep 17 00:00:00 2001
From: danielperano <51095634+danielperano@users.noreply.github.com>
Date: Thu, 22 Feb 2024 10:33:08 -0800
Subject: [PATCH] Corrected Local Bounds for Absolute Positioning

Yoga adds the offsets of a node into
the bounds when that node is positioned
absolutely. This removes the offsets
from the reported bounds in these
cases, since this is confusing
behavior that usually needs to be
accounted for downstream.
---
 .../myworld/obsidian/layout/LayoutEngine.java | 34 +++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/Obsidian/src/main/java/myworld/obsidian/layout/LayoutEngine.java b/Obsidian/src/main/java/myworld/obsidian/layout/LayoutEngine.java
index e92b2ce..2d3fb50 100644
--- a/Obsidian/src/main/java/myworld/obsidian/layout/LayoutEngine.java
+++ b/Obsidian/src/main/java/myworld/obsidian/layout/LayoutEngine.java
@@ -95,20 +95,50 @@ public float getHeight(Component component){
         return LAYOUT_UNDEFINED;
     }
 
+    protected boolean isAbsolute(Component component){
+        var isAbsolute = component.layout().positionType().is(PositionType.ABSOLUTE);
+        if(!isAbsolute && component.hasParent()){
+            return isAbsolute(component.getParent());
+        }
+        return isAbsolute;
+    }
+
     public Bounds2D getLocalBounds(Component component){
         var node = getYogaNode(component);
         if(node != null){
+            var isAbsolute = isAbsolute(component);
+            var offsets = component.layout().offsets().get(Offsets.ZERO);
+
+            var rawWidth = YGNodeLayoutGetWidth(node);
+            var rawHeight = YGNodeLayoutGetHeight(node);
+
+            var width = rawWidth;
+            var height = rawHeight;
+
+            if(isAbsolute){
+                // Yoga considers the offsets to be part of the width/height when absolute positioning is used,
+                // but this is very awkward for downstream consumers since it requires different layout logic.
+                // Instead, compute the visual bounds as usual without regard for offsets when absolute positioning
+                // is used.
+                width -= Math.abs(maybeAutoToPixels(offsets.left(), width) + maybeAutoToPixels(offsets.right(), width));
+                height -= Math.abs(maybeAutoToPixels(offsets.top(), height) + maybeAutoToPixels(offsets.bottom(), height));
+            }
+
             return new Bounds2D(
                     new Point2D(
                             YGNodeLayoutGetLeft(node),
                             YGNodeLayoutGetTop(node)),
-                    YGNodeLayoutGetWidth(node),
-                    YGNodeLayoutGetHeight(node)
+                    width,
+                    height
             );
         }
         return Bounds2D.UNDEFINED;
     }
 
+    protected float maybeAutoToPixels(Distance d, float pxSize){
+        return d.equals(Layout.AUTO) ? 0f : d.toPixels(pxSize);
+    }
+
     public Bounds2D getSceneBounds(Component component){
         var bounds = getLocalBounds(component);
         float x = bounds.origin().x();