From 3a7914ee6d4dd621439ac8643fb0be949a8a728d Mon Sep 17 00:00:00 2001
From: Alessandro Proto <me@alexdevs.me>
Date: Sat, 21 Jan 2023 15:56:32 +0100
Subject: [PATCH] Add length metamethod to GPUBuffer

---
 Capy64/LuaRuntime/Objects/GPUBuffer.cs | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/Capy64/LuaRuntime/Objects/GPUBuffer.cs b/Capy64/LuaRuntime/Objects/GPUBuffer.cs
index 9878b8c..c1bd6cf 100644
--- a/Capy64/LuaRuntime/Objects/GPUBuffer.cs
+++ b/Capy64/LuaRuntime/Objects/GPUBuffer.cs
@@ -27,6 +27,10 @@ public class GPUBuffer
             L.PushCFunction(LM_NewIndex);
             L.SetTable(-3);
 
+            L.PushString("__len");
+            L.PushCFunction(LM_Length);
+            L.SetTable(-3);
+
             L.PushString("__gc");
             L.PushCFunction(LM_GC);
             L.SetTable(-3);
@@ -114,4 +118,15 @@ public class GPUBuffer
 
         return 0;
     }
+
+    private static int LM_Length(IntPtr state)
+    {
+        var L = Lua.FromIntPtr(state);
+
+        var buffer = L.CheckObject<uint[]>(1, ObjectType, false);
+
+        L.PushInteger(buffer.LongLength);
+
+        return 1;
+    }
 }