From b61b4d3229774145aee71208e10246162b35c7f3 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Thu, 28 Feb 2019 14:06:56 +0100
Subject: [PATCH] Ensure that the temporary canvas created in
 `CanvasGraphics.isFontSubpixelAAEnabled` will be cleared

While this particular canvas may be small, there can still be an arbitrarily large number of them (one per page rendered), which can/will eventually add up memory wise. This can be easily avoided by using the `cachedCanvases` abstraction instead, which will ensure that the `isFontSubpixelAAEnabled` canvas is removed together with other temporary canvases in `CanvasGraphics.endDrawing`.
---
 src/display/canvas.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/display/canvas.js b/src/display/canvas.js
index 4aadb70a3..4647860fc 100644
--- a/src/display/canvas.js
+++ b/src/display/canvas.js
@@ -1414,7 +1414,8 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
     get isFontSubpixelAAEnabled() {
       // Checks if anti-aliasing is enabled when scaled text is painted.
       // On Windows GDI scaled fonts looks bad.
-      var ctx = this.canvasFactory.create(10, 10).context;
+      const { context: ctx, } =
+        this.cachedCanvases.getCanvas('isFontSubpixelAAEnabled', 10, 10);
       ctx.scale(1.5, 1);
       ctx.fillText('I', 0, 10);
       var data = ctx.getImageData(0, 0, 10, 10).data;