add Metal support for MULTISAMPLE_ARRAY (gfx-rs#9300)

Author: 39ali

wgpu-hal/src/metal/adapter.rs

@@ -1107,6 +1107,14 @@ impl super::CapabilitiesQuery {
                 false
             },
             shader_per_vertex: family_check && device.supportsFamily(MTLGPUFamily::Apple10),
+
+            //https://developer.apple.com/documentation/metal/mtltexturetype/type2dmultisamplearray
+            supports_multisample_array: available!(
+                macos = 10.14,
+                ios = 14.0,
+                tvos = 16.0,
+                visionos = 1.0
+            ),
         }
     }
 
@@ -1242,6 +1250,8 @@ impl super::CapabilitiesQuery {
 
         features.set(F::EXPERIMENTAL_RAY_QUERY, self.supports_raytracing);
 
+        features.set(F::MULTISAMPLE_ARRAY, self.supports_multisample_array);
+
         features
     }
 

wgpu-hal/src/metal/device.rs

@@ -493,7 +493,15 @@ impl crate::Device for super::Device {
                 wgt::TextureDimension::D2 => {
                     if desc.sample_count > 1 {
                         unsafe { descriptor.setSampleCount(desc.sample_count as usize) };
-                        MTLTextureType::Type2DMultisample
+
+                        if desc.size.depth_or_array_layers > 1 {
+                            unsafe {
+                                descriptor.setArrayLength(desc.size.depth_or_array_layers as usize)
+                            };
+                            MTLTextureType::Type2DMultisampleArray
+                        } else {
+                            MTLTextureType::Type2DMultisample
+                        }
                     } else if desc.size.depth_or_array_layers > 1 {
                         unsafe {
                             descriptor.setArrayLength(desc.size.depth_or_array_layers as usize)
@@ -560,7 +568,9 @@ impl crate::Device for super::Device {
         texture: &super::Texture,
         desc: &crate::TextureViewDescriptor,
     ) -> DeviceResult<super::TextureView> {
-        let raw_type = if texture.raw_type == MTLTextureType::Type2DMultisample {
+        let raw_type = if texture.raw_type == MTLTextureType::Type2DMultisample
+            || texture.raw_type == MTLTextureType::Type2DMultisampleArray
+        {
             texture.raw_type
         } else {
             conv::map_texture_view_dimension(desc.dimension)

wgpu-hal/src/metal/mod.rs

@@ -322,6 +322,7 @@ struct CapabilitiesQuery {
     supports_memoryless_storage: bool,
     supports_raytracing: bool,
     shader_per_vertex: bool,
+    supports_multisample_array: bool,
 }
 
 #[derive(Debug)]

wgpu-types/src/features.rs

@@ -1387,6 +1387,7 @@ bitflags_array! {
         ///
         /// Supported platforms:
         /// - Vulkan (except VK_KHR_portability_subset if multisampleArrayImage is not available)
+        /// - Metal (with macos 10.14+, ios 14.0+, tvos 16.0+, visionos 1.0+)
         #[name("wgpu-multisample-array")]
         const MULTISAMPLE_ARRAY = 1 << 56;