feat: tearing support

src/ext-protocol/all.h

@@ -1,4 +1,5 @@
 #include "dwl-ipc.h"
 #include "ext-workspace.h"
 #include "foreign-toplevel.h"
+#include "tearing.h"
 #include "text-input.h"

src/ext-protocol/tearing.h

@@ -0,0 +1,168 @@
+#include <wlr/types/wlr_tearing_control_v1.h>
+
+struct tearing_controller {
+	struct wlr_tearing_control_v1 *tearing_control;
+	struct wl_listener set_hint;
+	struct wl_listener destroy;
+};
+
+struct wlr_tearing_control_manager_v1 *tearing_control;
+struct wl_listener tearing_new_object;
+
+static void handle_controller_set_hint(struct wl_listener *listener,
+									   void *data) {
+	struct tearing_controller *controller =
+		wl_container_of(listener, controller, set_hint);
+	Client *c = get_client_from_surface(controller->tearing_control->surface);
+	if (c) {
+		/*
+		 * tearing_control->current is actually an enum:
+		 * WP_TEARING_CONTROL_V1_PRESENTATION_HINT_VSYNC = 0
+		 * WP_TEARING_CONTROL_V1_PRESENTATION_HINT_ASYNC = 1
+		 *
+		 * Using it as a bool here allows us to not ship the XML.
+		 */
+		c->tearing_hint = controller->tearing_control->current;
+	}
+}
+
+static void handle_controller_destroy(struct wl_listener *listener,
+									  void *data) {
+	struct tearing_controller *controller =
+		wl_container_of(listener, controller, destroy);
+	wl_list_remove(&controller->set_hint.link);
+	wl_list_remove(&controller->destroy.link);
+	free(controller);
+}
+
+void handle_tearing_new_object(struct wl_listener *listener, void *data) {
+	struct wlr_tearing_control_v1 *new_tearing_control = data;
+
+	enum wp_tearing_control_v1_presentation_hint hint =
+		wlr_tearing_control_manager_v1_surface_hint_from_surface(
+			tearing_control, new_tearing_control->surface);
+	wlr_log(WLR_DEBUG, "New presentation hint %d received for surface %p", hint,
+			new_tearing_control->surface);
+
+	struct tearing_controller *controller =
+		ecalloc(1, sizeof(struct tearing_controller));
+	controller->tearing_control = new_tearing_control;
+
+	controller->set_hint.notify = handle_controller_set_hint;
+	wl_signal_add(&new_tearing_control->events.set_hint, &controller->set_hint);
+
+	controller->destroy.notify = handle_controller_destroy;
+	wl_signal_add(&new_tearing_control->events.destroy, &controller->destroy);
+}
+
+bool check_tearing_frame_allow(Monitor *m) {
+	/* never allow tearing when disabled */
+	if (!allow_tearing) {
+		return false;
+	}
+
+	Client *c = selmon->sel;
+
+	/* tearing is only allowed for the output with the active client */
+	if (!c || c->mon != m) {
+		return false;
+	}
+
+	/* allow tearing for any window when requested or forced */
+	if (allow_tearing == TEARING_ENABLED) {
+		if (c->force_tearing == STATE_UNSPECIFIED) {
+			return c->tearing_hint;
+		} else {
+			return c->force_tearing == STATE_ENABLED;
+		}
+	}
+
+	/* remaining tearing options apply only to full-screen windows */
+	if (!c->isfullscreen) {
+		return false;
+	}
+
+	if (c->force_tearing == STATE_UNSPECIFIED) {
+		/* honor the tearing hint or the fullscreen-force preference */
+		return c->tearing_hint || allow_tearing == TEARING_FULLSCREEN_ONLY;
+	}
+
+	/* honor tearing as requested by action */
+	return c->force_tearing == STATE_ENABLED;
+}
+
+bool custom_wlr_scene_output_commit(struct wlr_scene_output *scene_output,
+									struct wlr_output_state *state) {
+	struct wlr_output *wlr_output = scene_output->output;
+	Monitor *m = wlr_output->data;
+
+	// 检查是否需要帧
+	if (!wlr_scene_output_needs_frame(scene_output)) {
+		wlr_log(WLR_DEBUG, "No frame needed for output %s", wlr_output->name);
+		return true;
+	}
+
+	// 构建输出状态
+	if (!wlr_scene_output_build_state(scene_output, state, NULL)) {
+		wlr_log(WLR_ERROR, "Failed to build output state for %s",
+				wlr_output->name);
+		return false;
+	}
+
+	// 测试撕裂翻页
+	if (state->tearing_page_flip) {
+		if (!wlr_output_test_state(wlr_output, state)) {
+			state->tearing_page_flip = false;
+		}
+	}
+
+	// 尝试提交
+	bool committed = wlr_output_commit_state(wlr_output, state);
+
+	// 如果启用撕裂翻页但提交失败，重试禁用撕裂翻页
+	if (!committed && state->tearing_page_flip) {
+		wlr_log(WLR_DEBUG, "Retrying commit without tearing for %s",
+				wlr_output->name);
+		state->tearing_page_flip = false;
+		committed = wlr_output_commit_state(wlr_output, state);
+	}
+
+	// 处理状态清理
+	if (committed) {
+		wlr_log(WLR_DEBUG, "Successfully committed output %s",
+				wlr_output->name);
+		if (state == &m->pending) {
+			wlr_output_state_finish(&m->pending);
+			wlr_output_state_init(&m->pending);
+		}
+	} else {
+		wlr_log(WLR_ERROR, "Failed to commit output %s", wlr_output->name);
+		// 即使提交失败，也清理状态避免积累
+		if (state == &m->pending) {
+			wlr_output_state_finish(&m->pending);
+			wlr_output_state_init(&m->pending);
+		}
+		return false;
+	}
+
+	return true;
+}
+
+void apply_tear_state(Monitor *m) {
+	if (wlr_scene_output_needs_frame(m->scene_output)) {
+		wlr_output_state_init(&m->pending);
+		if (wlr_scene_output_build_state(m->scene_output, &m->pending, NULL)) {
+			struct wlr_output_state *pending = &m->pending;
+			pending->tearing_page_flip = true;
+
+			if (!custom_wlr_scene_output_commit(m->scene_output, pending)) {
+				wlr_log(WLR_ERROR, "Failed to commit output %s",
+						m->scene_output->output->name);
+			}
+		} else {
+			wlr_log(WLR_ERROR, "Failed to build state for output %s",
+					m->scene_output->output->name);
+			wlr_output_state_finish(&m->pending);
+		}
+	}
+}