easy comptime hooks

src/nu/Render.zig

@@ -30,33 +30,11 @@ pub const Options = struct {
 var sc: au.SwapChain = undefined;
 var flights: au.Flights = undefined;
 
-const PresentCallback = *const fn (au.CommandBufferProxy) void;
-var present_callbacks: std.ArrayList(PresentCallback) = undefined;
-
-pub fn add_present_callback(cb: PresentCallback) !void {
-    if (std.mem.indexOfScalar(PresentCallback, present_callbacks.items, cb)) |_| {
-        return;
-    } else {
-        try present_callbacks.append(cb);
-    }
-}
-
-pub fn remove_present_callback(cb: PresentCallback) void {
-    if (std.mem.indexOfScalar(PresentCallback, present_callbacks.items, cb)) |idx| {
-        _ = present_callbacks.orderedRemove(idx);
-    } else {
-        return;
-    }
-}
-
 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();
 
-    present_callbacks = std.ArrayList(PresentCallback).init(alloc);
-    errdefer present_callbacks.deinit();
-
     sc = try au.SwapChain.init(alloc);
     errdefer sc.deinit();
 
@@ -64,7 +42,7 @@ pub fn init(alloc: std.mem.Allocator) !void {
     errdefer flights.deinit();
 }
 
-pub fn frame() !void {
+pub fn nu_frame() !void {
     const flight: au.Flights.Flight = flights.next();
     try flight.wait();
 
@@ -89,14 +67,11 @@ pub fn frame() !void {
 
         try cmd.beginCommandBuffer(&.{ .flags = .{ .one_time_submit_bit = true } });
         target.begin_rendering(cmd, render_area);
-        for (present_callbacks.items) |cb| {
-            cb(cmd);
-        }
 
-        // todo really don't like this.
-        // there should be some comptime means for a module to invoke hooks on other modules. eg there should be some
-        // "record" hook that for each module that gets called here; but if the render module is never added then that
-        // hook never gets called
+        // todo manage frame in flight state for each hook; pass the current flight in as context.
+        // will need some comptime -> anytype mapping.
+        try nu.invoke_hook("nu_render_present", .{cmd});
+
         target.end_rendering(cmd);
         try cmd.endCommandBuffer();
 
@@ -127,9 +102,11 @@ pub fn frame() !void {
     }
 }
 
+pub fn nu_close() !void {
+    try au.D.deviceWaitIdle();
+}
+
 pub fn deinit() void {
-    present_callbacks.deinit();
-    au.D.deviceWaitIdle() catch {};
     flights.deinit();
     sc.deinit();
     au.deinit();