runtime hooks

src/nu/ImGui.zig

@@ -6,6 +6,7 @@ const vk = @import("vk");
 const nu = @import("../nu.zig");
 const au = @import("Render/au.zig");
 
+const Hook = @import("hooks.zig").Hook;
 const Render = @import("Render.zig");
 const Window = @import("Window.zig");
 
@@ -14,6 +15,11 @@ pub usingnamespace im;
 
 pub const Options = struct {};
 
+pub const Hooks = struct {
+    pub const Frame = Hook(fn () void);
+    frame: Frame,
+};
+
 pub fn loader_wrapper(procname: [*c]const u8, _: ?*anyopaque) callconv(.C) vk.PfnVoidFunction {
     return au.glfwGetInstanceProcAddress(au.I.handle, procname);
 }
@@ -21,7 +27,9 @@ pub fn loader_wrapper(procname: [*c]const u8, _: ?*anyopaque) callconv(.C) vk.Pf
 var ctx: *im.ImGuiContext = undefined;
 var descriptor_pool: vk.DescriptorPool = undefined;
 
-pub fn init() !void {
+pub var hooks: Hooks = undefined;
+
+pub fn init(alloc: std.mem.Allocator) !void {
     ctx = im.igCreateContext(null) orelse {
         return error.igCreateContextFailed;
     };
@@ -77,6 +85,24 @@ pub fn init() !void {
     if (!im.impl.ImGui_ImplVulkan_CreateFontsTexture()) {
         return error.igVulkanFontTextureFailed;
     }
+
+    hooks = .{
+        .frame = Hooks.Frame.init(alloc),
+    };
+    errdefer hooks.frame.deinit();
+}
+
+pub fn deinit() void {
+    hooks.frame.deinit();
+    im.impl.ImGui_ImplVulkan_Shutdown();
+    au.D.destroyDescriptorPool(descriptor_pool, null);
+    im.impl.ImGui_ImplGlfw_Shutdown();
+    im.igDestroyContext(ctx);
+}
+
+pub fn connect() !void {
+    try nu.hooks.frame.register(nu_frame);
+    try Render.hooks.present.register(nu_render_present);
 }
 
 pub fn nu_frame() !void {
@@ -84,7 +110,7 @@ pub fn nu_frame() !void {
     im.impl.ImGui_ImplVulkan_NewFrame();
     im.igNewFrame();
 
-    try nu.invoke_hook("nu_imgui_frame", .{});
+    hooks.frame.invoke(.{});
 
     im.igEndFrame();
     im.igRender();
@@ -97,10 +123,3 @@ pub fn nu_render_present(cmd: au.CommandBufferProxy) void {
         null,
     );
 }
-
-pub fn deinit() void {
-    im.impl.ImGui_ImplVulkan_Shutdown();
-    au.D.destroyDescriptorPool(descriptor_pool, null);
-    im.impl.ImGui_ImplGlfw_Shutdown();
-    im.igDestroyContext(ctx);
-}