Introduce depth buffer finally

src/engine/Swapchain.zig

@@ -5,6 +5,7 @@ const vk = @import("vulkan");
 
 const Engine = @import("Engine.zig");
 const QSM = @import("QueueSharingMode.zig");
+const Texture = @import("Texture.zig");
 
 params: Params,
 render_pass: vk.RenderPass,
@@ -12,6 +13,7 @@ render_pass: vk.RenderPass,
 extent: vk.Extent2D = .{ .width = 0, .height = 0 },
 swapchain: vk.SwapchainKHR = .null_handle,
 swapchain_images: []SwapchainImage = &.{},
+depth_texture: ?Texture = null,
 image_index: u32 = 0,
 semaphore_image_acquired: vk.Semaphore = .null_handle,
 
@@ -35,6 +37,16 @@ pub fn init(engine: *Engine) !Swapchain {
                 .initial_layout = .undefined,
                 .final_layout = .present_src_khr,
             },
+            .{
+                .format = Texture.Usage.depth.vkFormat(),
+                .samples = .{ .@"1_bit" = true },
+                .load_op = .clear,
+                .store_op = .dont_care,
+                .stencil_load_op = .clear,
+                .stencil_store_op = .dont_care,
+                .initial_layout = .undefined,
+                .final_layout = .depth_stencil_attachment_optimal,
+            },
         };
 
         const color_attachments = [_]vk.AttachmentReference{
@@ -44,11 +56,39 @@ pub fn init(engine: *Engine) !Swapchain {
             },
         };
 
+        const depth_stencil_attachment: vk.AttachmentReference = .{
+            .attachment = 1,
+            .layout = .depth_stencil_attachment_optimal,
+        };
+
         const subpasses = [_]vk.SubpassDescription{
             .{
                 .pipeline_bind_point = .graphics,
                 .color_attachment_count = color_attachments.len,
                 .p_color_attachments = &color_attachments,
+                .p_depth_stencil_attachment = &depth_stencil_attachment,
+            },
+        };
+
+        const dependencies = [_]vk.SubpassDependency{
+            .{
+                .src_subpass = 0,
+                .dst_subpass = 0,
+                .src_stage_mask = .{
+                    .color_attachment_output_bit = true,
+                    .late_fragment_tests_bit = true,
+                },
+                .dst_stage_mask = .{
+                    .color_attachment_output_bit = true,
+                    .early_fragment_tests_bit = true,
+                },
+                .src_access_mask = .{
+                    .depth_stencil_attachment_write_bit = true,
+                },
+                .dst_access_mask = .{
+                    .color_attachment_write_bit = true,
+                    .depth_stencil_attachment_write_bit = true,
+                },
             },
         };
 
@@ -57,6 +97,8 @@ pub fn init(engine: *Engine) !Swapchain {
             .p_attachments = &attachments,
             .subpass_count = subpasses.len,
             .p_subpasses = &subpasses,
+            .dependency_count = dependencies.len,
+            .p_dependencies = &dependencies,
         }, &engine.vk_allocator.interface);
     };
     errdefer engine.device.destroyRenderPass(render_pass, &engine.vk_allocator.interface);
@@ -80,6 +122,10 @@ pub fn deinit(self: *Swapchain, engine: *Engine) void {
     }
     allocator.free(self.swapchain_images);
 
+    if (self.depth_texture) |*depth_texture| {
+        depth_texture.deinit(engine);
+    }
+
     if (self.swapchain != .null_handle) {
         engine.device.destroySwapchainKHR(self.swapchain, &engine.vk_allocator.interface);
     }
@@ -95,6 +141,7 @@ pub fn recreate(self: *Swapchain, engine: *Engine) !void {
 
     const old_swapchain = self.swapchain;
     const old_swapchain_images = self.swapchain_images;
+    var old_depth_texture = self.depth_texture;
     const old_semaphore_image_acquired = self.semaphore_image_acquired;
 
     const extent = try getCurrentExtent(engine);
@@ -137,6 +184,10 @@ pub fn recreate(self: *Swapchain, engine: *Engine) !void {
     allocator.free(self.swapchain_images);
     self.swapchain_images = &.{};
 
+    if (old_depth_texture) |*depth_texture| {
+        depth_texture.deinit(engine);
+    }
+
     if (old_swapchain != .null_handle) {
         engine.device.destroySwapchainKHR(old_swapchain, &engine.vk_allocator.interface);
         self.swapchain = .null_handle;
@@ -149,6 +200,16 @@ pub fn recreate(self: *Swapchain, engine: *Engine) !void {
         self.semaphore_image_acquired = .null_handle;
     }
 
+    // --- CREATE DEPTH TEXTURE ------------------------------------------------
+
+    var new_depth_texture = try Texture.init(engine, .{
+        .width = extent.width,
+        .height = extent.height,
+        .target_queue = .graphics,
+        .usage = .depth,
+    });
+    errdefer new_depth_texture.deinit(engine);
+
     // --- CREATE NEW SWAPCHAIN IMAGES -----------------------------------------
 
     const new_swapchain_images = blk: {
@@ -166,6 +227,7 @@ pub fn recreate(self: *Swapchain, engine: *Engine) !void {
                 .format = self.params.surface_format.format,
                 .render_pass = self.render_pass,
                 .extent = extent,
+                .depth_stencil_image_view = new_depth_texture.image_view,
             }));
         }
 
@@ -195,6 +257,7 @@ pub fn recreate(self: *Swapchain, engine: *Engine) !void {
     self.extent = extent;
     self.swapchain = new_swapchain;
     self.swapchain_images = new_swapchain_images;
+    self.depth_texture = new_depth_texture;
     self.image_index = res.image_index;
     self.semaphore_image_acquired = semaphore_image_acquired;
 }
@@ -359,6 +422,7 @@ const SwapchainImage = struct {
         format: vk.Format,
         render_pass: vk.RenderPass,
         extent: vk.Extent2D,
+        depth_stencil_image_view: vk.ImageView,
     };
 
     fn init(engine: *Engine, props: InitProps) !SwapchainImage {
@@ -389,7 +453,7 @@ const SwapchainImage = struct {
 
         const framebuffer = try engine.createFramebuffer(.{
             .render_pass = props.render_pass,
-            .attachments = &.{image_view},
+            .attachments = &.{ image_view, props.depth_stencil_image_view },
             .width = props.extent.width,
             .height = props.extent.height,
             .layers = 1,