From 6055bd3fa72c035a3ebd1068607d2446f74fec3e Mon Sep 17 00:00:00 2001
From: Nick Fisher <nick.fisher@avinium.com>
Date: Mon, 9 Jun 2025 18:10:07 +0800
Subject: [PATCH] fix FFIMaterial so it correctly translates between
 StencilFace (Dart) and TStencilFace (Dart FFI) enums

---
 .../src/implementation/ffi_material.dart      | 24 ++++++++++++++-----
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/thermion_dart/lib/src/filament/src/implementation/ffi_material.dart b/thermion_dart/lib/src/filament/src/implementation/ffi_material.dart
index 373b2168..8624077a 100644
--- a/thermion_dart/lib/src/filament/src/implementation/ffi_material.dart
+++ b/thermion_dart/lib/src/filament/src/implementation/ffi_material.dart
@@ -113,32 +113,33 @@ class FFIMaterialInstance extends MaterialInstance {
   @override
   Future setStencilCompareFunction(SamplerCompareFunction func,
       [StencilFace face = StencilFace.FRONT_AND_BACK]) async {
-    MaterialInstance_setStencilCompareFunction(pointer, func.index, face.index);
+    MaterialInstance_setStencilCompareFunction(
+        pointer, func.index, face.toFFI());
   }
 
   @override
   Future setStencilOpDepthFail(StencilOperation op,
       [StencilFace face = StencilFace.FRONT_AND_BACK]) async {
-    MaterialInstance_setStencilOpDepthFail(pointer, op.index, face.index);
+    MaterialInstance_setStencilOpDepthFail(pointer, op.index, face.toFFI());
   }
 
   @override
   Future setStencilOpDepthStencilPass(StencilOperation op,
       [StencilFace face = StencilFace.FRONT_AND_BACK]) async {
     MaterialInstance_setStencilOpDepthStencilPass(
-        pointer, op.index, face.index);
+        pointer, op.index, face.toFFI());
   }
 
   @override
   Future setStencilOpStencilFail(StencilOperation op,
       [StencilFace face = StencilFace.FRONT_AND_BACK]) async {
-    MaterialInstance_setStencilOpStencilFail(pointer, op.index, face.index);
+    MaterialInstance_setStencilOpStencilFail(pointer, op.index, face.toFFI());
   }
 
   @override
   Future setStencilReferenceValue(int value,
       [StencilFace face = StencilFace.FRONT_AND_BACK]) async {
-    MaterialInstance_setStencilReferenceValue(pointer, value, face.index);
+    MaterialInstance_setStencilReferenceValue(pointer, value, face.toFFI());
   }
 
   @override
@@ -169,7 +170,8 @@ class FFIMaterialInstance extends MaterialInstance {
 
   Future destroy() async {
     await withVoidCallback((requestId, cb) {
-      Engine_destroyMaterialInstanceRenderThread(app.engine, this.pointer, requestId, cb);
+      Engine_destroyMaterialInstanceRenderThread(
+          app.engine, this.pointer, requestId, cb);
     });
   }
 
@@ -197,3 +199,13 @@ class FFIMaterialInstance extends MaterialInstance {
         pointer, name.toNativeUtf8().cast<Char>(), matrix.storage.address);
   }
 }
+
+extension TStencilFaceExt on StencilFace {
+  int toFFI() {
+    return switch (this) {
+      StencilFace.FRONT => TStencilFace.STENCIL_FACE_FRONT,
+      StencilFace.BACK => TStencilFace.STENCIL_FACE_BACK,
+      StencilFace.FRONT_AND_BACK => TStencilFace.STENCIL_FACE_FRONT_AND_BACK
+    };
+  }
+}