vk: support unused bind groups

blade-graphics/src/vulkan/command.rs

@@ -833,22 +833,26 @@ impl super::PipelineEncoder<'_, '_> {
 impl crate::traits::PipelineEncoder for super::PipelineEncoder<'_, '_> {
     fn bind<D: crate::ShaderData>(&mut self, group: u32, data: &D) {
         let dsl = &self.layout.descriptor_set_layouts[group as usize];
-        self.update_data.clear();
-        self.update_data.resize(dsl.template_size as usize, 0);
-        data.fill(super::PipelineContext {
-            update_data: self.update_data.as_mut_slice(),
-            template_offsets: &dsl.template_offsets,
-        });
+        if !dsl.is_empty() {
+            self.update_data.clear();
+            self.update_data.resize(dsl.template_size as usize, 0);
+            data.fill(super::PipelineContext {
+                update_data: self.update_data.as_mut_slice(),
+                template_offsets: &dsl.template_offsets,
+            });
+        }
 
         let vk_set = self
             .device
             .allocate_descriptor_set(&mut self.cmd_buf.descriptor_pool, dsl);
         unsafe {
-            self.device.core.update_descriptor_set_with_template(
-                vk_set,
-                dsl.update_template,
-                self.update_data.as_ptr() as *const _,
-            );
+            if !dsl.is_empty() {
+                self.device.core.update_descriptor_set_with_template(
+                    vk_set,
+                    dsl.update_template,
+                    self.update_data.as_ptr() as *const _,
+                );
+            }
             self.device.core.cmd_bind_descriptor_sets(
                 self.cmd_buf.raw,
                 self.bind_point,

blade-graphics/src/vulkan/mod.rs

@@ -1,5 +1,5 @@
 use ash::{khr, vk};
-use std::{num::NonZeroU32, path::PathBuf, ptr, sync::Mutex};
+use std::{mem, num::NonZeroU32, path::PathBuf, ptr, sync::Mutex};
 
 mod command;
 mod descriptor;
@@ -222,6 +222,12 @@ struct DescriptorSetLayout {
     template_offsets: Box<[u32]>,
 }
 
+impl DescriptorSetLayout {
+    fn is_empty(&self) -> bool {
+        self.template_size == 0
+    }
+}
+
 #[derive(Debug)]
 struct PipelineLayout {
     raw: vk::PipelineLayout,
@@ -444,7 +450,7 @@ impl crate::traits::CommandDevice for Context {
         unsafe {
             self.device
                 .core
-                .destroy_command_pool(command_encoder.pool, None)
+                .destroy_command_pool(mem::take(&mut command_encoder.pool), None)
         };
         if let Some(crash_handler) = command_encoder.crash_handler.take() {
             self.destroy_buffer(crash_handler.marker_buf);

blade-graphics/src/vulkan/pipeline.rs

@@ -164,8 +164,18 @@ impl super::Context {
         info: &crate::ShaderDataInfo,
     ) -> super::DescriptorSetLayout {
         if info.visibility.is_empty() {
-            return super::DescriptorSetLayout::default();
+            // we need to have a valid `VkDescriptorSetLayout` regardless
+            return super::DescriptorSetLayout {
+                raw: unsafe {
+                    self.device
+                        .core
+                        .create_descriptor_set_layout(&Default::default(), None)
+                        .unwrap()
+                },
+                ..Default::default()
+            };
         }
+
         let stage_flags = map_shader_visibility(info.visibility);
         let mut vk_bindings = Vec::with_capacity(layout.bindings.len());
         let mut template_entries = Vec::with_capacity(layout.bindings.len());
@@ -230,6 +240,7 @@ impl super::Context {
                     vk::DescriptorBindingFlags::empty(),
                 ),
             };
+
             vk_bindings.push(vk::DescriptorSetLayoutBinding {
                 binding: binding_index as u32,
                 descriptor_type,
@@ -245,8 +256,8 @@ impl super::Context {
                 offset: update_offset,
                 stride: descriptor_size,
             });
-            template_offsets.push(update_offset as u32);
             binding_flags.push(flag);
+            template_offsets.push(update_offset as u32);
             update_offset += descriptor_size * descriptor_count as usize;
         }
 
@@ -310,16 +321,22 @@ impl super::Context {
 
     fn destroy_pipeline_layout(&self, layout: &mut super::PipelineLayout) {
         unsafe {
-            self.device.core.destroy_pipeline_layout(layout.raw, None);
+            self.device
+                .core
+                .destroy_pipeline_layout(mem::take(&mut layout.raw), None);
         }
         for dsl in layout.descriptor_set_layouts.drain(..) {
             unsafe {
                 self.device
                     .core
                     .destroy_descriptor_set_layout(dsl.raw, None);
-                self.device
-                    .core
-                    .destroy_descriptor_update_template(dsl.update_template, None);
+            }
+            if !dsl.is_empty() {
+                unsafe {
+                    self.device
+                        .core
+                        .destroy_descriptor_update_template(dsl.update_template, None);
+                }
             }
         }
     }

docs/CHANGELOG.md

@@ -16,6 +16,8 @@ Changelog for Blade
     - concurrent compute dispatches
   - Egl:
     - destroy old surface on resize
+  - Vulkan:
+    - support unused bind groups
 
 ## blade-egui-0.5 (09 Nov 2024)