From f44fd454260b04bf2bcec30a8bdba89449b20feb Mon Sep 17 00:00:00 2001
From: Diego Marcos <diego.marcos@gmail.com>
Date: Mon, 18 Mar 2019 17:52:16 -0700
Subject: [PATCH] Update vr drawing buffer size when the WebVRManager device is
 set. Fix scenarios where buffer size is set to the screen resolution instead
 of headset display's

---
 src/renderers/webvr/WebVRManager.js | 46 +++++++++++++++++++----------
 1 file changed, 31 insertions(+), 15 deletions(-)

diff --git a/src/renderers/webvr/WebVRManager.js b/src/renderers/webvr/WebVRManager.js
index 222fd18172d0eb..5314c2be35aae6 100644
--- a/src/renderers/webvr/WebVRManager.js
+++ b/src/renderers/webvr/WebVRManager.js
@@ -65,27 +65,14 @@ function WebVRManager( renderer ) {
 
 	function onVRDisplayPresentChange() {
 
-		if ( isPresenting() ) {
-
-			var eyeParameters = device.getEyeParameters( 'left' );
-			var renderWidth = eyeParameters.renderWidth * framebufferScaleFactor;
-			var renderHeight = eyeParameters.renderHeight * framebufferScaleFactor;
+		updateDrawingBufferSize();
 
-			currentPixelRatio = renderer.getPixelRatio();
-			renderer.getSize( currentSize );
-
-			renderer.setDrawingBufferSize( renderWidth * 2, renderHeight, 1 );
+		if ( isPresenting() ) {
 
 			animation.start();
 
 		} else {
 
-			if ( scope.enabled ) {
-
-				renderer.setDrawingBufferSize( currentSize.width, currentSize.height, currentPixelRatio );
-
-			}
-
 			animation.stop();
 
 		}
@@ -119,6 +106,31 @@ function WebVRManager( renderer ) {
 
 	}
 
+	function updateDrawingBufferSize() {
+
+		if ( isPresenting() ) {
+
+			var eyeParameters = device.getEyeParameters( 'left' );
+			var renderWidth = eyeParameters.renderWidth * framebufferScaleFactor;
+			var renderHeight = eyeParameters.renderHeight * framebufferScaleFactor;
+
+			renderer.setDrawingBufferSize( renderWidth * 2, renderHeight, 1 );
+
+		} else {
+
+			if ( scope.enabled ) {
+
+				currentPixelRatio = renderer.getPixelRatio();
+				renderer.getSize( currentSize );
+
+				renderer.setDrawingBufferSize( currentSize.width, currentSize.height, currentPixelRatio );
+
+			}
+
+		}
+
+	}
+
 	function updateControllers() {
 
 		for ( var i = 0; i < controllers.length; i ++ ) {
@@ -210,6 +222,10 @@ function WebVRManager( renderer ) {
 
 		animation.setContext( value );
 
+		updateDrawingBufferSize();
+
+		if ( isPresenting() ) animation.start();
+
 	};
 
 	this.setFramebufferScaleFactor = function ( value ) {