From 84db84bc23585d834e8b9d6d2562c215a6bdab6a Mon Sep 17 00:00:00 2001
From: ahocevar <andreas.hocevar@gmail.com>
Date: Wed, 8 May 2019 10:31:29 +0200
Subject: [PATCH] Avoid blurry vector tiles

---
 src/ol/renderer/canvas/VectorTileLayer.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/ol/renderer/canvas/VectorTileLayer.js b/src/ol/renderer/canvas/VectorTileLayer.js
index 1b74d9e4ba..9bdc6a94d3 100644
--- a/src/ol/renderer/canvas/VectorTileLayer.js
+++ b/src/ol/renderer/canvas/VectorTileLayer.js
@@ -614,6 +614,8 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
     const tileGrid = source.getTileGridForProjection(projection);
     const resolution = tileGrid.getResolution(z);
     const context = tile.getContext(layer);
+    // Increase tile size when overzooming for low pixel ratio, to avoid blurry tiles
+    pixelRatio = Math.max(pixelRatio, renderPixelRatio / pixelRatio);
     const size = source.getTilePixelSize(z, pixelRatio, projection);
     context.canvas.width = size[0];
     context.canvas.height = size[1];