From 187a216379e1a319e32d89e41e7c97518717f25d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maximilian=20Kr=C3=B6g?= <maxi_kroeg@web.de>
Date: Sun, 4 Oct 2020 19:01:45 +0200
Subject: [PATCH] Do not draw empty text styles

This fixes a rendering/flicker issue when an empty text style is decluttered
together with an image style.
---
 src/ol/renderer/vector.js | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/ol/renderer/vector.js b/src/ol/renderer/vector.js
index 0e01263ac0..7452b56b9e 100644
--- a/src/ol/renderer/vector.js
+++ b/src/ol/renderer/vector.js
@@ -82,7 +82,7 @@ function renderCircleGeometry(
     circleReplay.drawCircle(geometry, feature);
   }
   const textStyle = style.getText();
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = (opt_declutterBuilderGroup || builderGroup).getBuilder(
       style.getZIndex(),
       BuilderType.TEXT
@@ -251,7 +251,7 @@ function renderLineStringGeometry(
     lineStringReplay.drawLineString(geometry, feature);
   }
   const textStyle = style.getText();
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = (opt_declutterBuilderGroup || builderGroup).getBuilder(
       style.getZIndex(),
       BuilderType.TEXT
@@ -285,7 +285,7 @@ function renderMultiLineStringGeometry(
     lineStringReplay.drawMultiLineString(geometry, feature);
   }
   const textStyle = style.getText();
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = (opt_declutterBuilderGroup || builderGroup).getBuilder(
       style.getZIndex(),
       BuilderType.TEXT
@@ -320,7 +320,7 @@ function renderMultiPolygonGeometry(
     polygonReplay.drawMultiPolygon(geometry, feature);
   }
   const textStyle = style.getText();
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = (opt_declutterBuilderGroup || builderGroup).getBuilder(
       style.getZIndex(),
       BuilderType.TEXT
@@ -349,7 +349,8 @@ function renderPointGeometry(
   let sharedData;
   if (opt_declutterBuilderGroup) {
     builderGroup = opt_declutterBuilderGroup;
-    sharedData = imageStyle && textStyle ? {} : undefined;
+    sharedData =
+      imageStyle && textStyle && textStyle.getText() ? {} : undefined;
   }
   if (imageStyle) {
     if (imageStyle.getImageState() != ImageState.LOADED) {
@@ -362,7 +363,7 @@ function renderPointGeometry(
     imageReplay.setImageStyle(imageStyle, sharedData);
     imageReplay.drawPoint(geometry, feature);
   }
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = builderGroup.getBuilder(
       style.getZIndex(),
       BuilderType.TEXT
@@ -391,7 +392,8 @@ function renderMultiPointGeometry(
   let sharedData;
   if (opt_declutterBuilderGroup) {
     builderGroup = opt_declutterBuilderGroup;
-    sharedData = imageStyle && textStyle ? {} : undefined;
+    sharedData =
+      imageStyle && textStyle && textStyle.getText() ? {} : undefined;
   }
   if (imageStyle) {
     if (imageStyle.getImageState() != ImageState.LOADED) {
@@ -404,7 +406,7 @@ function renderMultiPointGeometry(
     imageReplay.setImageStyle(imageStyle, sharedData);
     imageReplay.drawMultiPoint(geometry, feature);
   }
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = (opt_declutterBuilderGroup || builderGroup).getBuilder(
       style.getZIndex(),
       BuilderType.TEXT
@@ -439,7 +441,7 @@ function renderPolygonGeometry(
     polygonReplay.drawPolygon(geometry, feature);
   }
   const textStyle = style.getText();
-  if (textStyle) {
+  if (textStyle && textStyle.getText()) {
     const textReplay = (opt_declutterBuilderGroup || builderGroup).getBuilder(
       style.getZIndex(),
       BuilderType.TEXT