[d3d12] refactor buffer/texture creation functions to return resources instead of using out params

Author: teoxoy

wgpu-hal/src/dx12/device.rs

@@ -388,7 +388,6 @@ impl crate::Device for super::Device {
         &self,
         desc: &crate::BufferDescriptor,
     ) -> Result<super::Buffer, crate::DeviceError> {
-        let mut resource = None;
         let mut size = desc.size;
         if desc.usage.contains(crate::BufferUses::UNIFORM) {
             let align_mask = Direct3D12::D3D12_CONSTANT_BUFFER_DATA_PLACEMENT_ALIGNMENT as u64 - 1;
@@ -411,10 +410,8 @@ impl crate::Device for super::Device {
             Flags: conv::map_buffer_usage_to_resource_flags(desc.usage),
         };
 
-        let allocation =
-            super::suballocation::create_buffer_resource(self, desc, raw_desc, &mut resource)?;
-
-        let resource = resource.ok_or(crate::DeviceError::ResourceCreationFailed)?;
+        let (resource, allocation) =
+            super::suballocation::create_buffer_resource(self, desc, raw_desc)?;
 
         if let Some(label) = desc.label {
             unsafe { resource.SetName(&windows::core::HSTRING::from(label)) }
@@ -471,10 +468,6 @@ impl crate::Device for super::Device {
         &self,
         desc: &crate::TextureDescriptor,
     ) -> Result<super::Texture, crate::DeviceError> {
-        use super::suballocation::create_texture_resource;
-
-        let mut resource = None;
-
         let raw_desc = Direct3D12::D3D12_RESOURCE_DESC {
             Dimension: conv::map_texture_dimension(desc.dimension),
             Alignment: 0,
@@ -496,9 +489,9 @@ impl crate::Device for super::Device {
             Flags: conv::map_texture_usage_to_resource_flags(desc.usage),
         };
 
-        let allocation = create_texture_resource(self, desc, raw_desc, &mut resource)?;
+        let (resource, allocation) =
+            super::suballocation::create_texture_resource(self, desc, raw_desc)?;
 
-        let resource = resource.ok_or(crate::DeviceError::ResourceCreationFailed)?;
         if let Some(label) = desc.label {
             unsafe { resource.SetName(&windows::core::HSTRING::from(label)) }
                 .into_device_result("SetName")?;

wgpu-hal/src/dx12/suballocation.rs

@@ -52,14 +52,14 @@ pub(crate) fn create_buffer_resource(
     device: &crate::dx12::Device,
     desc: &crate::BufferDescriptor,
     raw_desc: Direct3D12::D3D12_RESOURCE_DESC,
-    resource: &mut Option<Direct3D12::ID3D12Resource>,
-) -> Result<Option<AllocationWrapper>, crate::DeviceError> {
+) -> Result<(Direct3D12::ID3D12Resource, Option<AllocationWrapper>), crate::DeviceError> {
     let is_cpu_read = desc.usage.contains(crate::BufferUses::MAP_READ);
     let is_cpu_write = desc.usage.contains(crate::BufferUses::MAP_WRITE);
 
     // Workaround for Intel Xe drivers
     if !device.private_caps.suballocation_supported {
-        return create_committed_buffer_resource(device, desc, raw_desc, resource).map(|()| None);
+        return create_committed_buffer_resource(device, desc, raw_desc)
+            .map(|resource| (resource, None));
     }
 
     let location = match (is_cpu_read, is_cpu_write) {
@@ -80,6 +80,7 @@ pub(crate) fn create_buffer_resource(
         location,
     );
     let allocation = allocator.allocator.allocate(&allocation_desc)?;
+    let mut resource = None;
 
     unsafe {
         device.raw.CreatePlacedResource(
@@ -88,32 +89,30 @@ pub(crate) fn create_buffer_resource(
             &raw_desc,
             Direct3D12::D3D12_RESOURCE_STATE_COMMON,
             None,
-            resource,
+            &mut resource,
         )
     }
     .into_device_result("Placed buffer creation")?;
 
-    if resource.is_none() {
-        return Err(crate::DeviceError::ResourceCreationFailed);
-    }
+    let resource = resource.ok_or(crate::DeviceError::ResourceCreationFailed)?;
 
     device
         .counters
         .buffer_memory
         .add(allocation.size() as isize);
 
-    Ok(Some(AllocationWrapper { allocation }))
+    Ok((resource, Some(AllocationWrapper { allocation })))
 }
 
 pub(crate) fn create_texture_resource(
     device: &crate::dx12::Device,
     desc: &crate::TextureDescriptor,
     raw_desc: Direct3D12::D3D12_RESOURCE_DESC,
-    resource: &mut Option<Direct3D12::ID3D12Resource>,
-) -> Result<Option<AllocationWrapper>, crate::DeviceError> {
+) -> Result<(Direct3D12::ID3D12Resource, Option<AllocationWrapper>), crate::DeviceError> {
     // Workaround for Intel Xe drivers
     if !device.private_caps.suballocation_supported {
-        return create_committed_texture_resource(device, desc, raw_desc, resource).map(|()| None);
+        return create_committed_texture_resource(device, desc, raw_desc)
+            .map(|resource| (resource, None));
     }
 
     let location = MemoryLocation::GpuOnly;
@@ -128,6 +127,7 @@ pub(crate) fn create_texture_resource(
         location,
     );
     let allocation = allocator.allocator.allocate(&allocation_desc)?;
+    let mut resource = None;
 
     unsafe {
         device.raw.CreatePlacedResource(
@@ -136,21 +136,19 @@ pub(crate) fn create_texture_resource(
             &raw_desc,
             Direct3D12::D3D12_RESOURCE_STATE_COMMON,
             None, // clear value
-            resource,
+            &mut resource,
         )
     }
     .into_device_result("Placed texture creation")?;
 
-    if resource.is_none() {
-        return Err(crate::DeviceError::ResourceCreationFailed);
-    }
+    let resource = resource.ok_or(crate::DeviceError::ResourceCreationFailed)?;
 
     device
         .counters
         .texture_memory
         .add(allocation.size() as isize);
 
-    Ok(Some(AllocationWrapper { allocation }))
+    Ok((resource, Some(AllocationWrapper { allocation })))
 }
 
 pub(crate) fn free_buffer_allocation(
@@ -226,8 +224,7 @@ pub(crate) fn create_committed_buffer_resource(
     device: &crate::dx12::Device,
     desc: &crate::BufferDescriptor,
     raw_desc: Direct3D12::D3D12_RESOURCE_DESC,
-    resource: &mut Option<Direct3D12::ID3D12Resource>,
-) -> Result<(), crate::DeviceError> {
+) -> Result<Direct3D12::ID3D12Resource, crate::DeviceError> {
     let is_cpu_read = desc.usage.contains(crate::BufferUses::MAP_READ);
     let is_cpu_write = desc.usage.contains(crate::BufferUses::MAP_WRITE);
 
@@ -250,6 +247,8 @@ pub(crate) fn create_committed_buffer_resource(
         VisibleNodeMask: 0,
     };
 
+    let mut resource = None;
+
     unsafe {
         device.raw.CreateCommittedResource(
             &heap_properties,
@@ -261,24 +260,19 @@ pub(crate) fn create_committed_buffer_resource(
             &raw_desc,
             Direct3D12::D3D12_RESOURCE_STATE_COMMON,
             None,
-            resource,
+            &mut resource,
         )
     }
     .into_device_result("Committed buffer creation")?;
 
-    if resource.is_none() {
-        return Err(crate::DeviceError::ResourceCreationFailed);
-    }
-
-    Ok(())
+    resource.ok_or(crate::DeviceError::ResourceCreationFailed)
 }
 
 pub(crate) fn create_committed_texture_resource(
     device: &crate::dx12::Device,
     _desc: &crate::TextureDescriptor,
     raw_desc: Direct3D12::D3D12_RESOURCE_DESC,
-    resource: &mut Option<Direct3D12::ID3D12Resource>,
-) -> Result<(), crate::DeviceError> {
+) -> Result<Direct3D12::ID3D12Resource, crate::DeviceError> {
     let heap_properties = Direct3D12::D3D12_HEAP_PROPERTIES {
         Type: Direct3D12::D3D12_HEAP_TYPE_CUSTOM,
         CPUPageProperty: Direct3D12::D3D12_CPU_PAGE_PROPERTY_NOT_AVAILABLE,
@@ -290,6 +284,8 @@ pub(crate) fn create_committed_texture_resource(
         VisibleNodeMask: 0,
     };
 
+    let mut resource = None;
+
     unsafe {
         device.raw.CreateCommittedResource(
             &heap_properties,
@@ -301,14 +297,10 @@ pub(crate) fn create_committed_texture_resource(
             &raw_desc,
             Direct3D12::D3D12_RESOURCE_STATE_COMMON,
             None, // clear value
-            resource,
+            &mut resource,
         )
     }
     .into_device_result("Committed texture creation")?;
 
-    if resource.is_none() {
-        return Err(crate::DeviceError::ResourceCreationFailed);
-    }
-
-    Ok(())
+    resource.ok_or(crate::DeviceError::ResourceCreationFailed)
 }