From 09308af128f7762a8af60706cf8160a148aac4e9 Mon Sep 17 00:00:00 2001
From: Arthur031221 <levi74108520963@gmail.com>
Date: Thu, 1 Oct 2026 12:50:48 +0800
Subject: [PATCH] Also reset the vertex shader and UV_TRANSFORM define when
 clearing texture

The first version of this fix only null-guarded the uvTransform
uniform assignment. That left EffectPass out of sync: clearing
texture does not fire a change event unless setVertexShader() or
setChanged() runs, so the compound material kept compiling with
the UV_TRANSFORM code path and the now-null uvTransform uniform.
On the next render, three.js's WebGLUniforms would read .elements
off that null value and crash, just not at the assignment site.

Mirror the non-null branch: delete the UV_TRANSFORM define and
call setVertexShader(null) when the texture is cleared, so
EffectPass recompiles without the stale uniform reference. Added a
test that builds a real EffectPass around the effect and checks the
compiled vertex shader no longer references UvTransform after the
texture is cleared.
---
 src/effects/TextureEffect.js  |  9 ++++++++-
 test/effects/TextureEffect.js | 28 +++++++++++++++++++++++++++-
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/src/effects/TextureEffect.js b/src/effects/TextureEffect.js
index 17df28793..bb03e3fe2 100644
--- a/src/effects/TextureEffect.js
+++ b/src/effects/TextureEffect.js
@@ -60,11 +60,12 @@ export class TextureEffect extends Effect {
 		if(prevTexture !== value) {
 
 			uniforms.get("map").value = value;
-			uniforms.get("uvTransform").value = value.matrix;
 			defines.delete("TEXTURE_PRECISION_HIGH");
 
 			if(value !== null) {
 
+				uniforms.get("uvTransform").value = value.matrix;
+
 				if(value.matrixAutoUpdate) {
 
 					defines.set("UV_TRANSFORM", "1");
@@ -89,6 +90,12 @@ export class TextureEffect extends Effect {
 
 				}
 
+			} else {
+
+				uniforms.get("uvTransform").value = null;
+				defines.delete("UV_TRANSFORM");
+				this.setVertexShader(null);
+
 			}
 
 		}
diff --git a/test/effects/TextureEffect.js b/test/effects/TextureEffect.js
index 09f2541ee..318b74011 100644
--- a/test/effects/TextureEffect.js
+++ b/test/effects/TextureEffect.js
@@ -1,5 +1,6 @@
 import test from "ava";
-import { TextureEffect } from "postprocessing";
+import { Texture } from "three";
+import { EffectPass, TextureEffect } from "postprocessing";
 
 test("can be created and destroyed", t => {
 
@@ -16,3 +17,28 @@ test("can be updated", t => {
 	t.notThrows(() => effect.update());
 
 });
+
+test("can clear an existing texture", t => {
+
+	const effect = new TextureEffect({ texture: new Texture() });
+	t.notThrows(() => { effect.texture = null; });
+	t.is(effect.texture, null);
+
+});
+
+test("recompiles its host pass after clearing an existing texture", t => {
+
+	const texture = new Texture();
+	texture.matrixAutoUpdate = true;
+
+	const effect = new TextureEffect({ texture });
+	const pass = new EffectPass(null, effect);
+	pass.initialize(null, false, undefined);
+
+	t.true(pass.fullscreenMaterial.vertexShader.includes("UvTransform"));
+
+	t.notThrows(() => { effect.texture = null; });
+
+	t.false(pass.fullscreenMaterial.vertexShader.includes("UvTransform"));
+
+});