vulkan: don't create sampled-image descriptor for images without sample usage

src/gfx_apis/vulkan/blend_buffer.rs

@@ -42,6 +42,7 @@ impl VulkanRenderer {
         if width > limits.max_width || height > limits.max_height {
             return Err(VulkanError::ImageTooLarge);
         }
+        let usage = BLEND_USAGE;
         let create_info = ImageCreateInfo::default()
             .image_type(ImageType::TYPE_2D)
             .format(BLEND_FORMAT.vk_format)
@@ -56,7 +57,7 @@ impl VulkanRenderer {
                 height,
                 depth: 1,
             })
-            .usage(BLEND_USAGE);
+            .usage(usage);
         let image = unsafe { self.device.device.create_image(&create_info, None) };
         let image = image.map_err(VulkanError::CreateImage)?;
         let destroy_image = OnDrop(|| unsafe { self.device.device.destroy_image(image, None) });
@@ -105,7 +106,7 @@ impl VulkanRenderer {
             }),
             ty: VulkanImageMemory::Blend(allocation),
             bridge: None,
-            sampled_image_descriptor: self.sampled_image_descriptor(view),
+            sampled_image_descriptor: self.sampled_image_descriptor(usage, view),
             execution_version: Default::default(),
         });
         cached.insert_entry(Rc::downgrade(&img));

src/gfx_apis/vulkan/image.rs

@@ -64,7 +64,7 @@ pub struct VulkanImage {
     pub(super) queue_state: Cell<QueueState>,
     pub(super) ty: VulkanImageMemory,
     pub(super) bridge: Option<VulkanFramebufferBridge>,
-    pub(super) sampled_image_descriptor: Box<[u8]>,
+    pub(super) sampled_image_descriptor: Option<Box<[u8]>>,
     pub(super) execution_version: Cell<u64>,
 }
 
@@ -252,9 +252,16 @@ impl VulkanDevice {
 }
 
 impl VulkanRenderer {
-    pub(super) fn sampled_image_descriptor(&self, view: ImageView) -> Box<[u8]> {
+    pub(super) fn sampled_image_descriptor(
+        &self,
+        usage: ImageUsageFlags,
+        view: ImageView,
+    ) -> Option<Box<[u8]>> {
+        if !usage.contains(ImageUsageFlags::SAMPLED) {
+            return None;
+        }
         let Some(db) = &self.device.descriptor_buffer else {
-            return Box::new([]);
+            return None;
         };
         let mut buf = vec![0; self.device.sampled_image_descriptor_size].into_boxed_slice();
         let image_info = DescriptorImageInfo::default()
@@ -268,7 +275,7 @@ impl VulkanRenderer {
         unsafe {
             db.get_descriptor(&info, &mut buf);
         }
-        buf
+        Some(buf)
     }
 }
 
@@ -291,6 +298,7 @@ impl VulkanDmaBufImageTemplate {
         if self.width > limits.max_width || self.height > limits.max_height {
             return Err(VulkanError::ImageTooLarge);
         }
+        let usage;
         let image = {
             let plane_layouts: PlaneVec<_> = self
                 .dmabuf
@@ -313,7 +321,7 @@ impl VulkanDmaBufImageTemplate {
                 true => ImageCreateFlags::DISJOINT,
                 false => ImageCreateFlags::empty(),
             };
-            let usage = match for_rendering {
+            usage = match for_rendering {
                 true => match self.render_needs_bridge {
                     true => ImageUsageFlags::TRANSFER_DST,
                     false => ImageUsageFlags::TRANSFER_SRC | ImageUsageFlags::COLOR_ATTACHMENT,
@@ -464,7 +472,7 @@ impl VulkanDmaBufImageTemplate {
                 family: QueueFamily::Gfx,
             }),
             bridge,
-            sampled_image_descriptor: self.renderer.sampled_image_descriptor(texture_view),
+            sampled_image_descriptor: self.renderer.sampled_image_descriptor(usage, texture_view),
             execution_version: Cell::new(0),
         }))
     }

src/gfx_apis/vulkan/renderer.rs

@@ -624,7 +624,10 @@ impl VulkanRenderer {
             let layout = self.out_descriptor_set_layout.as_ref().unwrap();
             memory.blend_buffer_descriptor_buffer_offset = resource_writer.next_offset();
             let mut writer = resource_writer.add_set(layout);
-            writer.write(layout.offsets[0], &bb.sampled_image_descriptor);
+            writer.write(
+                layout.offsets[0],
+                bb.sampled_image_descriptor.as_ref().unwrap(),
+            );
             if let Some(addr) = memory.blend_buffer_color_management_data_address {
                 writer.write(
                     layout.offsets[1],
@@ -653,7 +656,7 @@ impl VulkanRenderer {
                 let mut writer = resource_writer.add_set(tex_descriptor_set_layout);
                 writer.write(
                     tex_descriptor_set_layout.offsets[0],
-                    &tex.sampled_image_descriptor,
+                    tex.sampled_image_descriptor.as_ref().unwrap(),
                 );
                 if let Some(addr) = c.color_management_data_address {
                     writer.write(

src/gfx_apis/vulkan/shm_image.rs

@@ -476,7 +476,7 @@ impl VulkanRenderer {
             }),
             ty: VulkanImageMemory::Internal(shm),
             bridge: None,
-            sampled_image_descriptor: self.sampled_image_descriptor(view),
+            sampled_image_descriptor: self.sampled_image_descriptor(usage, view),
             execution_version: Cell::new(0),
         });
         let shm = match &img.ty {