From 563b5e3711cf1fac756640bc42b3a10a737d2e5a Mon Sep 17 00:00:00 2001
From: 0b5vr <0b5vr@0b5vr.com>
Date: Tue, 4 Oct 2022 18:23:37 +0900
Subject: [PATCH] fix: Fix mtoon uv rotation direction

The rotation direction is in which rotates UV coordinates counter-clockwise (in U-right, V-down space)

Ref: https://github.com/KhronosGroup/glTF/pull/1624
---
 packages/three-vrm-materials-mtoon/src/shaders/mtoon.frag | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/three-vrm-materials-mtoon/src/shaders/mtoon.frag b/packages/three-vrm-materials-mtoon/src/shaders/mtoon.frag
index e551880aa..e31f75512 100644
--- a/packages/three-vrm-materials-mtoon/src/shaders/mtoon.frag
+++ b/packages/three-vrm-materials-mtoon/src/shaders/mtoon.frag
@@ -331,7 +331,7 @@ void main() {
     uv = uv + vec2( uvAnimationScrollXOffset, uvAnimationScrollYOffset ) * uvAnimMask;
     float uvRotCos = cos( uvAnimationRotationPhase * uvAnimMask );
     float uvRotSin = sin( uvAnimationRotationPhase * uvAnimMask );
-    uv = mat2( uvRotCos, uvRotSin, -uvRotSin, uvRotCos ) * ( uv - 0.5 ) + 0.5;
+    uv = mat2( uvRotCos, -uvRotSin, uvRotSin, uvRotCos ) * ( uv - 0.5 ) + 0.5;
   #endif
 
   #ifdef DEBUG_UV