From c2c3389f84873b60bad4c00a5c76716ef4e0a979 Mon Sep 17 00:00:00 2001
From: Igor Zinken <730069+igorski@users.noreply.github.com>
Date: Sat, 15 Mar 2025 06:43:41 +0100
Subject: [PATCH] More appropriate calculation for rendering blended layer
 bitmaps

---
 src/rendering/canvas-elements/layer-sprite.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/rendering/canvas-elements/layer-sprite.ts b/src/rendering/canvas-elements/layer-sprite.ts
index e40e02b..877e669 100644
--- a/src/rendering/canvas-elements/layer-sprite.ts
+++ b/src/rendering/canvas-elements/layer-sprite.ts
@@ -36,6 +36,7 @@ import { LayerTypes } from "@/definitions/layer-types";
 import ToolTypes, { canDrawOnSelection, TOOL_SRC_MERGED } from "@/definitions/tool-types";
 import { scaleRectangle, rotateRectangle } from "@/math/rectangle-math";
 import { translatePointerRotation, rotatePointer } from "@/math/point-math";
+import { fastRound } from "@/math/unit-math";
 import { renderEffectsForLayer } from "@/services/render-service";
 import { getBlendContext, blendLayer, hasBlend } from "@/rendering/blending";
 import { clipContextToSelection } from "@/rendering/clipping";
@@ -692,7 +693,11 @@ export default class LayerSprite extends ZoomableSprite {
                     bitmap = createSyncSnapshot( document, getBlendableLayers());
                     cacheBlendedLayer( layerIndex, bitmap );
                 }
-                documentContext.drawImage( bitmap, -viewport.left, -viewport.top, document.width, document.height );
+                const pixelRatio = getPixelRatio();
+                documentContext.drawImage(
+                    bitmap, -fastRound( viewport.left ), -fastRound( viewport.top ),
+                    fastRound( bitmap.width / pixelRatio ), fastRound( bitmap.height / pixelRatio )
+                );
                 renderedFromCache = true;
             }
         }