Make more progress towards tinywl in zig

src/main.zig

@@ -1,11 +1,24 @@
+const std = @import("std");
+
 const c = @cImport({
     @cDefine("WLR_USE_UNSTABLE", {});
     @cInclude("wayland-server-core.h");
-    @cInclude("wlr/backend.h");
+    @cInclude("wlr/render/wlr_renderer.h");
+    @cInclude("wlr/types/wlr_cursor.h");
+    @cInclude("wlr/types/wlr_compositor.h");
+    @cInclude("wlr/types/wlr_data_device.h");
+    @cInclude("wlr/types/wlr_input_device.h");
+    @cInclude("wlr/types/wlr_keyboard.h");
+    @cInclude("wlr/types/wlr_matrix.h");
+    @cInclude("wlr/types/wlr_output.h");
+    @cInclude("wlr/types/wlr_output_layout.h");
+    @cInclude("wlr/types/wlr_pointer.h");
+    @cInclude("wlr/types/wlr_seat.h");
+    @cInclude("wlr/types/wlr_xcursor_manager.h");
+    @cInclude("wlr/types/wlr_xdg_shell.h");
     @cInclude("wlr/util/log.h");
-    @cInclude("wlr/types/wlr_xdg_shell.h>");
+    @cInclude("xkbcommon/xkbcommon.h");
 });
-const std = @import("std");
 
 const CursorMode = enum {
     Passthrough,
@@ -27,10 +40,118 @@ fn create_listener() c.wl_listener {
     };
 }
 
+const RenderData = struct {
+    output: *c.wlr_output,
+    renderer: *c.wlr_renderer,
+    view: *View,
+    when: *std.os.timespec,
+};
+
+fn output_frame(listener: *c.wl_listener, data: *c_void) void {
+    // This function is called every time an output is ready to display a frame,
+    // generally at the output's refresh rate (e.g. 60Hz). */
+    var output = @fieldParentPtr(Output, "frame", listener);
+    var renderer = output.*.server.*.renderer;
+
+    var now = undefined;
+    std.os.linux.clock_gettime(std.os.CLOCK_MONOTONIC, &now);
+
+    // wlr_output_attach_render makes the OpenGL context current.
+    if (!c.wlr_output_attach_render(output.*.wlr_output, null)) {
+        return;
+    }
+    // The "effective" resolution can change if you rotate your outputs.
+    var width = undefined;
+    var height = undefined;
+    c.wlr_output_effective_resolution(output.*.wlr_output, &width, &height);
+    // Begin the renderer (calls glViewport and some other GL sanity checks)
+    c.wlr_renderer_begin(renderer, width, height);
+
+    const color = [_]f32{ 0.3, 0.3, 0.3, 1.0 };
+    c.wlr_renderer_clear(renderer, color);
+
+    // Each subsequent window we render is rendered on top of the last. Because
+    //  our view list is ordered front-to-back, we iterate over it backwards.
+    // wl_list_for_each_reverse(view, &output.*.server.*.views, link) {
+
+    var view = @fieldParentPtr(View, "link", &output.*.server.*.views.*.prev);
+
+    while (&view.*.link != &output.*.server.*.views) {
+        if (!view.*.mapped) {
+            // An unmapped view should not be rendered.
+            continue;
+        }
+        var rdata = RenderData{
+            .output = output.*.wlr_output,
+            .view = view,
+            .renderer = renderer,
+            .when = &now,
+        };
+        // This calls our render_surface function for each surface among the
+        // xdg_surface's toplevel and popups.
+        c.wlr_xdg_surface_for_each_surface(view.*.xdg_surface, render_surface, &rdata);
+
+        // Move to next item in list
+        view = @fieldParentPtr(View, "link", view.*.link.*.prev);
+    }
+
+    // Hardware cursors are rendered by the GPU on a separate plane, and can be
+    // moved around without re-rendering what's beneath them - which is more
+    // efficient. However, not all hardware supports hardware cursors. For this
+    // reason, wlroots provides a software fallback, which we ask it to render
+    // here. wlr_cursor handles configuring hardware vs software cursors for you,
+    // and this function is a no-op when hardware cursors are in use.
+    c.wlr_output_render_software_cursors(output.*.wlr_output, null);
+
+    // Conclude rendering and swap the buffers, showing the final frame
+    // on-screen.
+    c.wlr_renderer_end(renderer);
+    c.wlr_output_commit(output.*.wlr_output);
+}
+
+fn server_new_output(listener: *c.wl_listener, data: *c_void) void {
+    var server = @fieldParentPtr(Server, "new_output", listener);
+    var wlr_output = @ptrCast(c.wlr_output, data);
+
+    // Some backends don't have modes. DRM+KMS does, and we need to set a mode
+    // before we can use the output. The mode is a tuple of (width, height,
+    // refresh rate), and each monitor supports only a specific set of modes. We
+    // just pick the monitor's preferred mode, a more sophisticated compositor
+    // would let the user configure it.
+    if (!c.wl_list_empty(&wlr_output.*.modes)) {
+        var mode = wlr_output_preferred_mode(wlr_output);
+        c.wlr_output_set_mode(wlr_output, mode);
+        c.wlr_output_enable(wlr_output, true);
+        if (!c.wlr_output_commit(wlr_output)) {
+            return;
+        }
+    }
+
+    // Allocates and configures our state for this output
+    var output = std.heap.c_allocator.create(Output) catch unreachable;
+    output.*.wlr_output = wlr_output;
+    output.*.server = server;
+    // Sets up a listener for the frame notify event.
+    output.*.frame.notify = output_frame;
+    c.wl_signal_add(&wlr_output.*.events.frame, &output.*.frame);
+    c.wl_list_insert(&server.*.outputs, &output.*.link);
+
+    // Adds this to the output layout. The add_auto function arranges outputs
+    // from left-to-right in the order they appear. A more sophisticated
+    // compositor would let the user configure the arrangement of outputs in the
+    // layout.
+    c.wlr_output_layout_add_auto(server.*.output_layout, wlr_output);
+
+    // Creating the global adds a wl_output global to the display, which Wayland
+    // clients can see to find out information about the output (such as
+    // DPI, scale factor, manufacturer, etc).
+    c.wlr_output_create_global(wlr_output);
+}
+
 const Server = struct {
-    wl_display: ?*c.wl_display,
+    wl_display: *c.wl_display,
-    backend: ?*c.wlr_backend,
+    backend: *c.wlr_backend,
-    renderer: ?*c.wlr_renderer,
+    renderer: *c.wlr_renderer,
 
     xdg_shell: ?*c.wlr_xdg_shell,
     new_xdg_surface: c.wl_listener,
@@ -49,7 +170,7 @@ const Server = struct {
     request_cursor: c.wl_listener,
     keyboards: c.wl_list,
     cursor_mode: CursorMode,
-    grabbed_view: ?*c.tinywl_view,
+    grabbed_view: ?*View,
     grab_x: f64,
     grab_y: f64,
     grab_width: c_int,
@@ -59,6 +180,95 @@ const Server = struct {
     output_layout: ?*c.wlr_output_layout,
     outputs: c.wl_list,
     new_output: c.wl_listener,
+
+    fn create() Server {
+        const wl_display = c.wl_display_create();
+        const backend = c.wlr_backend_autocreate(wl_display, null);
+        const renderer = c.wlr_backend_get_renderer(server.backend);
+        wlr_renderer_init_wl_display(renderer, wl_display);
+
+        wlr_compositor_create(wl_display, renderer);
+        wlr_data_device_manager_create(wl_display);
+
+        const output_layout = wlr_output_layout_create();
+        var outputs = create_list();
+        wl_list_init(&outputs);
+
+        new_output = create_listener();
+        server.new_output.notify = server_new_output;
+        wl_signal_add(&server.backend.*.events.new_output, &server.new_output);
+
+        return Server{
+            .wl_display = wl_display,
+            .backend = backend,
+            .renderer = null,
+
+            .xdg_shell = null,
+            .new_xdg_surface = create_listener(),
+            .views = create_list(),
+
+            .cursor = null,
+            .cursor_mgr = null,
+            .cursor_motion = create_listener(),
+            .cursor_motion_absolute = create_listener(),
+            .cursor_button = create_listener(),
+            .cursor_axis = create_listener(),
+            .cursor_frame = create_listener(),
+
+            .seat = null,
+            .new_input = create_listener(),
+            .request_cursor = create_listener(),
+            .keyboards = create_list(),
+            .cursor_mode = CursorMode.Passthrough,
+            .grabbed_view = null,
+            .grab_x = 0.0,
+            .grab_y = 0.0,
+            .grab_width = 0,
+            .grab_height = 0,
+            .resize_edges = 0,
+
+            .output_layout = null,
+            .outputs = c.wl_list{ .prev = null, .next = null },
+            .new_output = create_listener(),
+        };
+    }
+};
+
+const Output = struct {
+    link: c.wl_list,
+    server: *c.tinywl_server,
+    xdg_surface: ?*c.wlr_xdg_surface,
+    map: c.wl_listener,
+    unmap: c.wl_listener,
+    destroy: c.wl_listener,
+    request_move: c.wl_listener,
+    request_resize: c.wl_listener,
+    mapped: bool,
+    x: c_int,
+    y: c_int,
+};
+
+const View = struct {
+    link: c.wl_list,
+    server: *Server,
+    xdg_surface: ?*c.wlr_xdg_surface,
+    map: c.wl_listener,
+    unmap: c.wl_listener,
+    destroy: c.wl_listener,
+    request_move: c.wl_listener,
+    request_resize: c.wl_listener,
+    mapped: bool,
+    x: c_int,
+    y: c_int,
+};
+
+const Keyboard = struct {
+    link: c.wl_list,
+    server: *Server,
+    device: ?*c.wlr_input_device,
+
+    modifiers: c.wl_listener,
+    key: c.wl_listener,
 };
 
 pub fn main() !void {
@@ -66,37 +276,5 @@ pub fn main() !void {
 
     c.wlr_log_init(c.enum_wlr_log_importance.WLR_DEBUG, null);
 
-    var server = Server{
+    var server = Server.create();
-        .wl_display = null,
-        .backend = null,
-        .renderer = null,
-
-        .xdg_shell = null,
-        .new_xdg_surface = create_listener(),
-        .views = c.wl_list,
-
-        .cursor = null,
-        .cursor_mgr = null,
-        .cursor_motion = create_listener(),
-        .cursor_motion_absolute = create_listener(),
-        .cursor_button = create_listener(),
-        .cursor_axis = create_listener(),
-        .cursor_frame = create_listener(),
-
-        .seat = null,
-        .new_input = create_listener(),
-        .request_cursor = create_listener(),
-        .keyboards = c.wl_list,
-        .cursor_mode = CursorMode.Passthrough,
-        .grabbed_view = null,
-        .grab_x = 0.0,
-        .grab_y = 0.0,
-        .grab_width = 0,
-        .grab_height = 0,
-        .resize_edges = 0,
-
-        .output_layout = null,
-        .outputs = c.wl_list{ .prev = null, .next = null },
-        .new_output = create_listener(){},
-    };
 }