Remove Feature::TRANSIENT_ATTACHMENTS and add validation

Author: opstic

wgpu-core/src/command/render.rs

@@ -625,6 +625,8 @@ pub enum ColorAttachmentError {
         mip_level: u32,
         depth_or_array_layer: u32,
     },
+    #[error("Color attachment's usage cannot contain {0:?} if StoreOp is {1:?}")]
+    InvalidUsageForStoreOp(TextureUsages, StoreOp),
 }
 
 impl WebGpuError for ColorAttachmentError {
@@ -1585,6 +1587,17 @@ impl Global {
                     let view = texture_views.get(*view_id).get()?;
                     view.same_device(device)?;
 
+                    if view.desc.usage.contains(TextureUsages::TRANSIENT)
+                        && *store_op != StoreOp::Discard
+                    {
+                        return Err(RenderPassErrorInner::ColorAttachment(
+                            ColorAttachmentError::InvalidUsageForStoreOp(
+                                TextureUsages::TRANSIENT,
+                                *store_op,
+                            ),
+                        ));
+                    }
+
                     let resolve_target = if let Some(resolve_target_id) = resolve_target {
                         let rt_arc = texture_views.get(*resolve_target_id).get()?;
                         rt_arc.same_device(device)?;

wgpu-core/src/device/resource.rs

@@ -1262,6 +1262,17 @@ impl Device {
             }
         }
 
+        if desc.usage.contains(wgt::TextureUsages::TRANSIENT) {
+            let extra_usage =
+                desc.usage - wgt::TextureUsages::TRANSIENT - wgt::TextureUsages::RENDER_ATTACHMENT;
+            if !extra_usage.is_empty() {
+                return Err(CreateTextureError::IncompatibleUsage(
+                    wgt::TextureUsages::TRANSIENT,
+                    extra_usage,
+                ));
+            }
+        }
+
         let format_features = self
             .describe_format_features(desc.format)
             .map_err(|error| CreateTextureError::MissingFeatures(desc.format, error))?;
@@ -4464,10 +4475,6 @@ impl Device {
         {
             format_features.flags.set(tfsc::FILTERABLE, false);
         }
-        format_features.allowed_usages.set(
-            wgt::TextureUsages::TRANSIENT,
-            self.features.contains(wgt::Features::TRANSIENT_ATTACHMENTS),
-        );
         format_features
     }
 

wgpu-core/src/instance.rs

@@ -706,6 +706,7 @@ impl Adapter {
             wgt::TextureUsages::STORAGE_ATOMIC,
             caps.contains(Tfc::STORAGE_ATOMIC),
         );
+        allowed_usages |= wgt::TextureUsages::TRANSIENT;
 
         let mut flags = wgt::TextureFormatFeatureFlags::empty();
         flags.set(

wgpu-core/src/resource.rs

@@ -1509,6 +1509,8 @@ pub enum CreateTextureError {
     CreateTextureView(#[from] CreateTextureViewError),
     #[error("Invalid usage flags {0:?}")]
     InvalidUsage(wgt::TextureUsages),
+    #[error("Texture usage {0:?} is not compatible with texture usage {1:?}")]
+    IncompatibleUsage(wgt::TextureUsages, wgt::TextureUsages),
     #[error(transparent)]
     InvalidDimension(#[from] TextureDimensionError),
     #[error("Depth texture ({1:?}) can't be created as {0:?}")]
@@ -1564,6 +1566,7 @@ impl WebGpuError for CreateTextureError {
             Self::MissingDownlevelFlags(e) => e,
 
             Self::InvalidUsage(_)
+            | Self::IncompatibleUsage(_, _)
             | Self::InvalidDepthDimension(_, _)
             | Self::InvalidCompressedDimension(_, _)
             | Self::InvalidMipLevelCount { .. }

wgpu-hal/src/metal/adapter.rs

@@ -1002,8 +1002,6 @@ impl super::PrivateCapabilities {
             features.insert(F::SUBGROUP | F::SUBGROUP_BARRIER);
         }
 
-        features.set(F::TRANSIENT_ATTACHMENTS, self.supports_memoryless_storage);
-
         features
     }
 

wgpu-hal/src/vulkan/adapter.rs

@@ -560,8 +560,7 @@ impl PhysicalDeviceFeatures {
             | F::PIPELINE_CACHE
             | F::SHADER_EARLY_DEPTH_TEST
             | F::TEXTURE_ATOMIC
-            | F::EXPERIMENTAL_PASSTHROUGH_SHADERS
-            | F::TRANSIENT_ATTACHMENTS;
+            | F::EXPERIMENTAL_PASSTHROUGH_SHADERS;
 
         let mut dl_flags = Df::COMPUTE_SHADERS
             | Df::BASE_VERTEX

wgpu-types/src/features.rs

@@ -1231,17 +1231,6 @@ bitflags_array! {
         ///
         /// [`Device::create_shader_module_passthrough`]: https://docs.rs/wgpu/latest/wgpu/struct.Device.html#method.create_shader_module_passthrough
         const EXPERIMENTAL_PASSTHROUGH_SHADERS = 1 << 52;
-
-        /// Allows transient attachments to be created with [`TextureUsages::TRANSIENT`]
-        ///
-        /// Supported platforms
-        ///  - Vulkan
-        ///  - Metal
-        ///
-        /// This is a native only feature
-        ///
-        /// [`TextureUsages::TRANSIENT`]: super::TextureUsages::TRANSIENT
-        const TRANSIENT_ATTACHMENTS = 1 << 53;
     }
 
     /// Features that are not guaranteed to be supported.

wgpu-types/src/lib.rs

@@ -5610,7 +5610,7 @@ bitflags::bitflags! {
         //
         /// Allows a texture to be used with image atomics. Requires [`Features::TEXTURE_ATOMIC`].
         const STORAGE_ATOMIC = 1 << 16;
-        /// Allows a texture to be transient. Requires [`Features::TRANSIENT_ATTACHMENTS`].
+        /// Allows a texture to be transient. No-op on platforms other than Vulkan and Metal.
         const TRANSIENT = 1 << 17;
     }
 }