feat: optimization matrix algorithm (#516)

Optimize the time-consuming logic of matrix calculations, Fix jitter problem under long list --------- Co-authored-by: Edmond <[email protected]> Co-authored-by: edmond.l <[email protected]> Co-authored-by: TIANCHENG <[email protected]>
openwebf · Nov 23, 2023 · 877be25 · 877be25
1 parent 8399d53
commit 877be25
Show file tree

Hide file tree

Showing 2 changed files with 22 additions and 10 deletions.
diff --git a/webf/lib/src/rendering/box_model.dart b/webf/lib/src/rendering/box_model.dart
@@ -37,27 +37,31 @@ class RenderLayoutParentData extends ContainerBoxParentData<RenderBox> {
 //
 // ReturgetLayoutTransformTolocal layout coordinate system to the
 // coordinate system of `ancestor`.
-Matrix4 getLayoutTransformTo(RenderObject current, RenderObject ancestor, {bool excludeScrollOffset = false}) {
+Offset getLayoutTransformTo(RenderObject current, RenderObject ancestor, {bool excludeScrollOffset = false}) {
   final List<RenderObject> renderers = <RenderObject>[];
   for (RenderObject renderer = current; renderer != ancestor; renderer = renderer.parent!) {
     renderers.add(renderer);
     assert(renderer.parent != null);
   }
   renderers.add(ancestor);
+  Offset offset = Offset.zero;
 
   final Matrix4 transform = Matrix4.identity();
   for (int index = renderers.length - 1; index > 0; index -= 1) {
     RenderObject parentRenderer = renderers[index];
     RenderObject childRenderer = renderers[index - 1];
     // Apply the layout transform for renderBoxModel and fallback to paint transform for other renderObject type.
     if (parentRenderer is RenderBoxModel) {
-      parentRenderer.applyLayoutTransform(childRenderer, transform, excludeScrollOffset);
-    } else {
-      parentRenderer.applyPaintTransform(childRenderer, transform);
+      offset += parentRenderer.obtainLayoutTransform(childRenderer, excludeScrollOffset);
+    } else if (parentRenderer is RenderBox) {
+      assert(childRenderer.parent == parentRenderer);
+      if (childRenderer.parentData is BoxParentData) {
+        offset += (childRenderer.parentData as BoxParentData).offset;
+      }
     }
   }
 
-  return transform;
+  return offset;
 }
 
 /// Modified from Flutter rendering/box.dart.
@@ -1159,6 +1163,17 @@ class RenderBoxModel extends RenderBox
     transform.translate(offset.dx, offset.dy);
   }
 
+  Offset obtainLayoutTransform(RenderObject child, bool excludeScrollOffset) {
+    assert(child.parent == this);
+    assert(child.parentData is BoxParentData);
+    final BoxParentData childParentData = child.parentData! as BoxParentData;
+    Offset offset = childParentData.offset;
+    if (excludeScrollOffset) {
+      offset -= Offset(scrollLeft, scrollTop);
+    }
+    return offset;
+  }
+
   // The max scrollable size.
   Size _maxScrollableSize = Size.zero;
 
@@ -1355,9 +1370,7 @@ class RenderBoxModel extends RenderBox
     double ancestorBorderLeft = ancestor.renderStyle.borderLeftWidth?.computedValue ?? 0;
     Offset ancestorBorderWidth = Offset(ancestorBorderLeft, ancestorBorderTop);
 
-    return MatrixUtils.transformPoint(
-        getLayoutTransformTo(this, ancestor, excludeScrollOffset: excludeScrollOffset), point) -
-        ancestorBorderWidth;
+    return getLayoutTransformTo(this, ancestor, excludeScrollOffset: excludeScrollOffset) + point - ancestorBorderWidth;
   }
 
   bool _hasLocalBackgroundImage(CSSRenderStyle renderStyle) {

diff --git a/webf/lib/src/rendering/render_position_holder.dart b/webf/lib/src/rendering/render_position_holder.dart
@@ -48,8 +48,7 @@ class RenderPositionPlaceholder extends RenderPreferredSize {
   // Get the layout offset of renderObject to its ancestor which does not include the paint offset
   // such as scroll or transform.
   Offset getOffsetToAncestor(Offset point, RenderObject ancestor, {bool excludeScrollOffset = false}) {
-    return MatrixUtils.transformPoint(
-        getLayoutTransformTo(this, ancestor, excludeScrollOffset: excludeScrollOffset), point);
+    return getLayoutTransformTo(this, ancestor, excludeScrollOffset: excludeScrollOffset) + point;
   }
 }