render with swapchain

src/nu/Render.zig

@@ -6,6 +6,7 @@ const std = @import("std");
 const builtin = @import("builtin");
 const vk = @import("vk");
 
+const nu = @import("../nu.zig");
 const au = @import("Render/au.zig");
 
 pub const Options = struct {
@@ -26,15 +27,79 @@ pub const Options = struct {
     frames_in_flight: u8 = 3,
 };
 
-pub fn init(alloc: std.mem.Allocator) !void {
-    // todo make ctx not globals
+var sc: au.SwapChain = undefined;
+var flights: au.Flights = undefined;
 
+pub fn init(alloc: std.mem.Allocator) !void {
+    // todo pick apart au into helpers; not a sub-module filled with its own globals.
     try au.init(alloc);
     errdefer au.deinit();
+
+    sc = try au.SwapChain.init(alloc);
+    errdefer sc.deinit();
+
+    flights = try au.Flights.init(alloc, nu.options.render.frames_in_flight);
+    errdefer flights.deinit();
 }
 
-pub fn frame() void {}
+pub fn frame() !void {
+    const flight: au.Flights.Flight = flights.next();
+    try flight.wait();
+
+    while (true) {
+        _ = try sc.rebuild();
+
+        const target = sc.acquire(flight.acquire, .null_handle) catch |err| switch (err) {
+            error.OutOfDateKHR => {
+                sc.mark();
+                continue;
+            },
+            else => return err,
+        };
+
+        const render_area: vk.Rect2D = .{
+            .offset = .{ .x = 0, .y = 0 },
+            .extent = sc.cinfo.image_extent,
+        };
+
+        try au.D.resetCommandPool(flight.pool, .{});
+        var cmd = au.CommandBufferProxy.init(flight.cmd, au.D.wrapper);
+
+        try cmd.beginCommandBuffer(&.{ .flags = .{ .one_time_submit_bit = true } });
+        target.begin_rendering(cmd, render_area);
+        target.end_rendering(cmd);
+        try cmd.endCommandBuffer();
+
+        try au.Q.submit(1, &.{
+            vk.SubmitInfo{
+                .wait_semaphore_count = 1,
+                .p_wait_semaphores = &.{flight.acquire},
+                .p_wait_dst_stage_mask = &.{
+                    vk.PipelineStageFlags{ .color_attachment_output_bit = true },
+                },
+                .command_buffer_count = 1,
+                .p_command_buffers = &.{cmd.handle},
+                .signal_semaphore_count = 1,
+                .p_signal_semaphores = &.{flight.complete},
+            },
+        }, flight.fence);
+
+        if (sc.present(&.{flight.complete}, target)) |_| {
+            return;
+        } else |err| switch (err) {
+            error.OutOfDateKHR => {
+                try flight.wait();
+                sc.mark();
+                continue;
+            },
+            else => return err,
+        }
+    }
+}
 
 pub fn deinit() void {
+    au.D.deviceWaitIdle() catch {};
+    flights.deinit();
+    sc.deinit();
     au.deinit();
 }