From d6d5c095521429daf3151e4bb4b968aa15235927 Mon Sep 17 00:00:00 2001
From: Richard Davey <rich@photonstorm.com>
Date: Mon, 7 Dec 2020 12:19:42 +0000
Subject: [PATCH] The `Shader` Game Object now supports being able to use a
 Render Texture as a `sampler2D` texture on the shader. Fix #5423

---
 src/gameobjects/shader/Shader.js      | 10 ++++++++--
 src/renderer/webgl/PipelineManager.js | 12 +++++-------
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/gameobjects/shader/Shader.js b/src/gameobjects/shader/Shader.js
index a610a2acd..2947689d0 100644
--- a/src/gameobjects/shader/Shader.js
+++ b/src/gameobjects/shader/Shader.js
@@ -728,6 +728,12 @@ var Shader = new Class({
         if (textureManager.exists(textureKey))
         {
             var frame = textureManager.getFrame(textureKey);
+
+            if (frame.glTexture && frame.glTexture.isRenderTexture)
+            {
+                return this.setSampler2DBuffer(uniformKey, frame.glTexture, frame.width, frame.height, textureIndex, textureData);
+            }
+
             var uniform = this.uniforms[uniformKey];
             var source = frame.source;
 
@@ -908,7 +914,7 @@ var Shader = new Class({
 
         var data = uniform.textureData;
 
-        if (data)
+        if (data && !uniform.value.isRenderTexture)
         {
             // https://developer.mozilla.org/en-US/docs/Web/API/WebGLRenderingContext/texImage2D
 
@@ -1017,7 +1023,7 @@ var Shader = new Class({
             }
             else if (uniform.type === 'sampler2D')
             {
-                gl.activeTexture(gl['TEXTURE' + textureCount]);
+                gl.activeTexture(gl.TEXTURE0 + textureCount);
 
                 gl.bindTexture(gl.TEXTURE_2D, value);
 
diff --git a/src/renderer/webgl/PipelineManager.js b/src/renderer/webgl/PipelineManager.js
index 34da62524..8f6b92ccc 100644
--- a/src/renderer/webgl/PipelineManager.js
+++ b/src/renderer/webgl/PipelineManager.js
@@ -967,11 +967,6 @@ var PipelineManager = new Class({
             pipeline = this.previous;
         }
 
-        if (!pipeline)
-        {
-            return;
-        }
-
         var renderer = this.renderer;
         var gl = renderer.gl;
 
@@ -995,9 +990,12 @@ var PipelineManager = new Class({
 
         renderer.setBlendMode(0, true);
 
-        this.current = pipeline;
+        if (pipeline)
+        {
+            this.current = pipeline;
 
-        pipeline.rebind();
+            pipeline.rebind();
+        }
 
         renderer.resetTextures();
     },