Now we have a spinning square

src/app/data.rs

@@ -68,6 +68,8 @@ pub(crate) struct AppData {
     index_buffer_memory: vk::DeviceMemory,
     uniform_buffers: Vec<vk::Buffer>,
     pub(super) uniform_buffers_memory: Vec<vk::DeviceMemory>,
+    descriptor_pool: vk::DescriptorPool,
+    descriptor_sets: Vec<vk::DescriptorSet>,
     // Command Buffers
     pub(super) command_buffers: Vec<vk::CommandBuffer>,
     // Sync Objects
@@ -103,6 +105,8 @@ impl AppData {
         self.create_vertex_buffer(&instance, &device)?;
         self.create_index_buffer(&instance, &device)?;
         self.create_uniform_buffers(&instance, &device)?;
+        self.create_descriptor_pool(&device)?;
+        self.create_descriptor_sets(&device)?;
         self.create_command_buffers(&device)?;
         self.create_sync_objects(&device)?;
 
@@ -194,6 +198,7 @@ impl AppData {
     /// # Safety
     /// Here be Dragons
     unsafe fn destroy_swapchain(&mut self, device: &Device) {
+        device.destroy_descriptor_pool(self.descriptor_pool, None);
         self.uniform_buffers
             .iter()
             .for_each(|b| device.destroy_buffer(*b, None));
@@ -423,6 +428,8 @@ impl AppData {
         self.create_pipeline(device)?;
         self.create_framebuffers(device)?;
         self.create_uniform_buffers(instance, device)?;
+        self.create_descriptor_pool(device)?;
+        self.create_descriptor_sets(device)?;
         self.create_command_buffers(device)?;
 
         self.images_in_flight
@@ -573,7 +580,7 @@ impl AppData {
             .polygon_mode(vk::PolygonMode::FILL)
             .line_width(1.0)
             .cull_mode(vk::CullModeFlags::BACK)
-            .front_face(vk::FrontFace::CLOCKWISE)
+            .front_face(vk::FrontFace::COUNTER_CLOCKWISE)
             .depth_bias_enable(false);
 
         let multisample_state = vk::PipelineMultisampleStateCreateInfo::builder()
@@ -826,6 +833,49 @@ impl AppData {
         Ok(())
     }
 
+    unsafe fn create_descriptor_pool(&mut self, device: &Device) -> Result<()> {
+        let ubo_size = vk::DescriptorPoolSize::builder()
+            .type_(vk::DescriptorType::UNIFORM_BUFFER)
+            .descriptor_count(self.swapchain_images.len() as u32);
+
+        let pool_sizes = &[ubo_size];
+        let info = vk::DescriptorPoolCreateInfo::builder()
+            .pool_sizes(pool_sizes)
+            .max_sets(self.swapchain_images.len() as u32);
+
+        self.descriptor_pool = device.create_descriptor_pool(&info, None)?;
+
+        Ok(())
+    }
+
+    unsafe fn create_descriptor_sets(&mut self, device: &Device) -> Result<()> {
+        let layouts = vec![self.descriptor_set_layout; self.swapchain_images.len()];
+        let info = vk::DescriptorSetAllocateInfo::builder()
+            .descriptor_pool(self.descriptor_pool)
+            .set_layouts(&layouts);
+
+        self.descriptor_sets = device.allocate_descriptor_sets(&info)?;
+
+        for i in 0..self.swapchain_images.len() {
+            let info = vk::DescriptorBufferInfo::builder()
+                .buffer(self.uniform_buffers[i])
+                .offset(0)
+                .range(size_of::<UniformBufferObject>() as u64);
+
+            let buffer_info = &[info];
+            let ubo_write = vk::WriteDescriptorSet::builder()
+                .dst_set(self.descriptor_sets[i])
+                .dst_binding(0)
+                .dst_array_element(0)
+                .descriptor_type(vk::DescriptorType::UNIFORM_BUFFER)
+                .buffer_info(buffer_info);
+
+            device.update_descriptor_sets(&[ubo_write], &[] as &[vk::CopyDescriptorSet]);
+        }
+
+        Ok(())
+    }
+
     //================================================
     // Command Buffers
     //================================================
@@ -879,6 +929,14 @@ impl AppData {
                 0,
                 vk::IndexType::UINT16,
             );
+            device.cmd_bind_descriptor_sets(
+                *command_buffer,
+                vk::PipelineBindPoint::GRAPHICS,
+                self.pipeline_layout,
+                0,
+                &[self.descriptor_sets[i]],
+                &[],
+            );
             device.cmd_draw_indexed(*command_buffer, INDICES.len() as u32, 1, 0, 0, 0);
             device.cmd_end_render_pass(*command_buffer);