enumerate all physical devices

Gryphn/apis/GryphnMetal/src/metal_device.m

@@ -1,9 +1,16 @@
+#import "Metal/Metal.h"
 #include "metal_functions.h"
 #include "stdio.h"
 #include "stdint.h"
 
 gnReturnCode metalEnumeratePhysicalDevices(gnInstance instance, uint32_t* deviceCount, gnPhysicalDevice* devices) {
-    *deviceCount = 0;
+    NSArray<id<MTLDevice>>* mtlDevices = MTLCopyAllDevices();
+    uint32_t systemCount = (uint32_t)[mtlDevices count];
+    *deviceCount = systemCount;
+
+    if (devices == NULL)
+        return GN_SUCCESS;
+    for (uint32_t i = 0; i < *deviceCount; i++)
+        devices[i] = (gnPhysicalDevice)mtlDevices[i];
     return GN_SUCCESS;
 }
-c