The ForwardDiffuseLightPipeline, used by the Lights system, now sets a flag if the Scene doesn't contain any lights. All of the Game Objects now check this flag and don't even bother adding themselves to the batch if there are no lights in the Scene, as they'd never render anyway. This also avoids the ghost-image problem if you swap Scenes to a new Scene with the Light Manager enabled, but no actual lights defined. Fix phaserjs#3707

Author: photonstorm

CHANGELOG.md

@@ -9,6 +9,8 @@
 
 ### Updates
 
+* The ForwardDiffuseLightPipeline, used by the Lights system, now sets a flag if the Scene doesn't contain any lights. All of the Game Objects now check this flag and don't even bother adding themselves to the batch if there are no lights in the Scene, as they'd never render anyway. This also avoids the ghost-image problem if you swap Scenes to a new Scene with the Light Manager enabled, but no actual lights defined. Fix #3707 (thanks @samvieten)
+
 ### Bug Fixes
 
 * The Canvas RenderTexture drawImage method incorrectly set the values of the frame, causing them to appear wrongly scaled in the canvas renderer. Fix #3710 (thanks @saqsun)

src/renderer/webgl/WebGLPipeline.js

@@ -226,6 +226,16 @@ var WebGLPipeline = new Class({
          * @since 3.1.0
          */
         this.flushLocked = false;
+
+        /**
+         * Indicates if the current pipeline is active or not for this frame only.
+         * Reset in the onRender method.
+         *
+         * @name Phaser.Renderer.WebGL.WebGLPipeline#active
+         * @type {boolean}
+         * @since 3.10.0
+         */
+        this.active = false;
     },
 
     /**

src/renderer/webgl/pipelines/ForwardDiffuseLightPipeline.js

@@ -75,44 +75,49 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     onRender: function (scene, camera)
     {
+        this.active = false;
+
         var lightManager = scene.sys.lights;
 
-        if (!lightManager)
+        if (!lightManager || lightManager.lights.length <= 0 || !lightManager.active)
         {
+            //  Passthru
             return this;
         }
 
-        lightManager.culledLights.length = 0;
+        var lights = lightManager.cull(camera);
+        var lightCount = Math.min(lights.length, LIGHT_COUNT);
 
-        if (lightManager.lights.length <= 0 || !lightManager.active)
+        if (lightCount === 0)
         {
-            return this; // If not visible lights just passthrough
+            return this;
         }
 
+        this.active = true;
+
         var renderer = this.renderer;
         var program = this.program;
-        var lights = lightManager.cull(camera);
-        var lightCount = Math.min(lights.length, LIGHT_COUNT);
         var cameraMatrix = camera.matrix;
         var point = {x: 0, y: 0};
         var height = renderer.height;
         var index;
 
         for (index = 0; index < LIGHT_COUNT; ++index)
         {
-            renderer.setFloat1(program, 'uLights[' + index + '].radius', 0); // reset lights
+            //  Reset lights
+            renderer.setFloat1(program, 'uLights[' + index + '].radius', 0);
         }
 
-        if (lightCount <= 0) { return this; }
-
         renderer.setFloat4(program, 'uCamera', camera.x, camera.y, camera.rotation, camera.zoom);
         renderer.setFloat3(program, 'uAmbientLightColor', lightManager.ambientColor.r, lightManager.ambientColor.g, lightManager.ambientColor.b);
 
         for (index = 0; index < lightCount; ++index)
         {
             var light = lights[index];
             var lightName = 'uLights[' + index + '].';
+
             cameraMatrix.transformPoint(light.x, light.y, point);
+
             renderer.setFloat2(program, lightName + 'position', point.x - (camera.scrollX * light.scrollFactorX * camera.zoom), height - (point.y - (camera.scrollY * light.scrollFactorY) * camera.zoom));
             renderer.setFloat3(program, lightName + 'color', light.r, light.g, light.b);
             renderer.setFloat1(program, lightName + 'intensity', light.intensity);
@@ -135,6 +140,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     drawStaticTilemapLayer: function (tilemap, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = tilemap.tileset.image.dataSource[0];
 
         if (normalTexture)
@@ -163,6 +173,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     drawEmitterManager: function (emitterManager, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = emitterManager.texture.dataSource[emitterManager.frame.sourceIndex];
 
         if (normalTexture)
@@ -191,6 +206,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     drawBlitter: function (blitter, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = blitter.texture.dataSource[blitter.frame.sourceIndex];
 
         if (normalTexture)
@@ -219,6 +239,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     batchSprite: function (sprite, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = sprite.texture.dataSource[sprite.frame.sourceIndex];
 
         if (normalTexture)
@@ -247,6 +272,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     batchMesh: function (mesh, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = mesh.texture.dataSource[mesh.frame.sourceIndex];
 
         if (normalTexture)
@@ -276,6 +306,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     batchBitmapText: function (bitmapText, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = bitmapText.texture.dataSource[bitmapText.frame.sourceIndex];
 
         if (normalTexture)
@@ -332,6 +367,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     batchText: function (text, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = text.texture.dataSource[text.frame.sourceIndex];
 
         if (normalTexture)
@@ -360,6 +400,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     batchDynamicTilemapLayer: function (tilemapLayer, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = tilemapLayer.tileset.image.dataSource[0];
 
         if (normalTexture)
@@ -388,6 +433,11 @@ var ForwardDiffuseLightPipeline = new Class({
      */
     batchTileSprite: function (tileSprite, camera, parentTransformMatrix)
     {
+        if (!this.active)
+        {
+            return;
+        }
+
         var normalTexture = tileSprite.texture.dataSource[tileSprite.frame.sourceIndex];
 
         if (normalTexture)