backend/wayland: use wlr_swapchain for main surface

The cursor surface still uses a wl_egl_window.

References: https://github.com/swaywm/wlroots/issues/1352

backend/wayland/backend.c

@@ -2,6 +2,7 @@
 #include <limits.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 #include <wlr/config.h>
 
@@ -16,7 +17,10 @@
 #include <wlr/util/log.h>
 
 #include "backend/wayland.h"
+#include "render/drm_format_set.h"
+#include "render/gbm_allocator.h"
 #include "util/signal.h"
+
 #include "linux-dmabuf-unstable-v1-client-protocol.h"
 #include "pointer-gestures-unstable-v1-client-protocol.h"
 #include "presentation-time-client-protocol.h"
@@ -277,7 +281,8 @@ struct wlr_backend *wlr_wl_backend_create(struct wl_display *display,
 	}
 
 	wl_registry_add_listener(wl->registry, &registry_listener, wl);
-	wl_display_roundtrip(wl->remote_display);
+	wl_display_roundtrip(wl->remote_display); // get globals
+	wl_display_roundtrip(wl->remote_display); // get linux-dmabuf formats
 
 	if (!wl->compositor) {
 		wlr_log(WLR_ERROR,
@@ -317,12 +322,42 @@ struct wlr_backend *wlr_wl_backend_create(struct wl_display *display,
 
 	wl->renderer = create_renderer_func(&wl->egl, EGL_PLATFORM_WAYLAND_EXT,
 		wl->remote_display, config_attribs, 0);
-
 	if (!wl->renderer) {
 		wlr_log(WLR_ERROR, "Could not create renderer");
 		goto error_event;
 	}
 
+	// TODO: get FD from linux-dmabuf hints instead
+	int drm_fd = wlr_renderer_get_drm_fd(wl->renderer);
+	if (drm_fd < 0) {
+		wlr_log(WLR_ERROR, "Failed to get DRM device FD from renderer");
+		goto error_event;
+	}
+
+	drm_fd = dup(drm_fd);
+	if (drm_fd < 0) {
+		wlr_log_errno(WLR_ERROR, "dup failed");
+		goto error_event;
+	}
+
+	struct wlr_gbm_allocator *alloc = wlr_gbm_allocator_create(drm_fd);
+	if (alloc == NULL) {
+		wlr_log(WLR_ERROR, "Failed to create GBM allocator");
+		goto error_event;
+	}
+	wl->allocator = &alloc->base;
+
+	uint32_t fmt = DRM_FORMAT_ARGB8888;
+	const struct wlr_drm_format *remote_format =
+		wlr_drm_format_set_get(&wl->linux_dmabuf_v1_formats, fmt);
+	if (remote_format == NULL) {
+		wlr_log(WLR_ERROR, "Remote compositor doesn't support ARGB8888 "
+			"via linux-dmabuf-unstable-v1");
+		goto error_event;
+	}
+	// TODO: intersect with render formats
+	wl->format = wlr_drm_format_dup(remote_format);
+
 	wl->local_display_destroy.notify = handle_display_destroy;
 	wl_display_add_destroy_listener(display, &wl->local_display_destroy);
 

backend/wayland/output.c

@@ -15,7 +15,10 @@
 #include <wlr/util/log.h>
 
 #include "backend/wayland.h"
+#include "render/swapchain.h"
+#include "render/wlr_renderer.h"
 #include "util/signal.h"
+
 #include "linux-dmabuf-unstable-v1-client-protocol.h"
 #include "presentation-time-client-protocol.h"
 #include "xdg-decoration-unstable-v1-client-protocol.h"
@@ -94,17 +97,40 @@ static const struct wp_presentation_feedback_listener
 static bool output_set_custom_mode(struct wlr_output *wlr_output,
 		int32_t width, int32_t height, int32_t refresh) {
 	struct wlr_wl_output *output = get_wl_output_from_output(wlr_output);
-	wl_egl_window_resize(output->egl_window, width, height, 0, 0);
+
+	if (wlr_output->width != width || wlr_output->height != height) {
+		struct wlr_swapchain *swapchain = wlr_swapchain_create(
+			output->backend->allocator, width, height, output->backend->format);
+		if (swapchain == NULL) {
+			return false;
+		}
+		wlr_swapchain_destroy(output->swapchain);
+		output->swapchain = swapchain;
+	}
+
 	wlr_output_update_custom_mode(&output->wlr_output, width, height, 0);
 	return true;
 }
 
 static bool output_attach_render(struct wlr_output *wlr_output,
 		int *buffer_age) {
-	struct wlr_wl_output *output =
-		get_wl_output_from_output(wlr_output);
-	return wlr_egl_make_current(&output->backend->egl, output->egl_surface,
-		buffer_age);
+	struct wlr_wl_output *output = get_wl_output_from_output(wlr_output);
+
+	wlr_buffer_unlock(output->back_buffer);
+	output->back_buffer = wlr_swapchain_acquire(output->swapchain, buffer_age);
+	if (!output->back_buffer) {
+		return false;
+	}
+
+	if (!wlr_egl_make_current(&output->backend->egl, EGL_NO_SURFACE, NULL)) {
+		return false;
+	}
+	if (!wlr_renderer_bind_buffer(output->backend->renderer,
+			output->back_buffer)) {
+		return false;
+	}
+
+	return true;
 }
 
 static void destroy_wl_buffer(struct wlr_wl_buffer *buffer) {
@@ -246,39 +272,49 @@ static bool output_commit(struct wlr_output *wlr_output) {
 		output->frame_callback = wl_surface_frame(output->surface);
 		wl_callback_add_listener(output->frame_callback, &frame_listener, output);
 
+		struct wlr_buffer *wlr_buffer = NULL;
 		switch (wlr_output->pending.buffer_type) {
 		case WLR_OUTPUT_STATE_BUFFER_RENDER:
-			if (!wlr_egl_swap_buffers(&output->backend->egl,
-					output->egl_surface, damage)) {
-				return false;
-			}
+			assert(output->back_buffer != NULL);
+			wlr_buffer = output->back_buffer;
+
+			wlr_renderer_bind_buffer(output->backend->renderer, NULL);
+			wlr_egl_unset_current(&output->backend->egl);
 			break;
 		case WLR_OUTPUT_STATE_BUFFER_SCANOUT:;
-			struct wlr_wl_buffer *buffer =
-				create_wl_buffer(output->backend, wlr_output->pending.buffer);
-			if (buffer == NULL) {
-				return false;
-			}
-
-			wl_surface_attach(output->surface, buffer->wl_buffer, 0, 0);
-
-			if (damage == NULL) {
-				wl_surface_damage_buffer(output->surface,
-					0, 0, INT32_MAX, INT32_MAX);
-			} else {
-				int rects_len;
-				pixman_box32_t *rects =
-					pixman_region32_rectangles(damage, &rects_len);
-				for (int i = 0; i < rects_len; i++) {
-					pixman_box32_t *r = &rects[i];
-					wl_surface_damage_buffer(output->surface, r->x1, r->y1,
-						r->x2 - r->x1, r->y2 - r->y1);
-				}
-			}
-			wl_surface_commit(output->surface);
+			wlr_buffer = wlr_output->pending.buffer;
 			break;
 		}
 
+		struct wlr_wl_buffer *buffer =
+			create_wl_buffer(output->backend, wlr_buffer);
+		if (buffer == NULL) {
+			return false;
+		}
+
+		wl_surface_attach(output->surface, buffer->wl_buffer, 0, 0);
+
+		if (damage == NULL) {
+			wl_surface_damage_buffer(output->surface,
+				0, 0, INT32_MAX, INT32_MAX);
+		} else {
+			int rects_len;
+			pixman_box32_t *rects =
+				pixman_region32_rectangles(damage, &rects_len);
+			for (int i = 0; i < rects_len; i++) {
+				pixman_box32_t *r = &rects[i];
+				wl_surface_damage_buffer(output->surface, r->x1, r->y1,
+					r->x2 - r->x1, r->y2 - r->y1);
+			}
+		}
+
+		wl_surface_commit(output->surface);
+
+		wlr_buffer_unlock(output->back_buffer);
+		output->back_buffer = NULL;
+
+		wlr_swapchain_set_buffer_submitted(output->swapchain, wlr_buffer);
+
 		if (wp_feedback != NULL) {
 			struct wlr_wl_presentation_feedback *feedback =
 				calloc(1, sizeof(*feedback));
@@ -302,8 +338,8 @@ static bool output_commit(struct wlr_output *wlr_output) {
 }
 
 static void output_rollback_render(struct wlr_output *wlr_output) {
-	struct wlr_wl_output *output =
-		get_wl_output_from_output(wlr_output);
+	struct wlr_wl_output *output = get_wl_output_from_output(wlr_output);
+	wlr_renderer_bind_buffer(output->backend->renderer, NULL);
 	wlr_egl_unset_current(&output->backend->egl);
 }
 
@@ -407,8 +443,8 @@ static void output_destroy(struct wlr_output *wlr_output) {
 		presentation_feedback_destroy(feedback);
 	}
 
-	wlr_egl_destroy_surface(&output->backend->egl, output->egl_surface);
-	wl_egl_window_destroy(output->egl_window);
+	wlr_buffer_unlock(output->back_buffer);
+	wlr_swapchain_destroy(output->swapchain);
 	if (output->zxdg_toplevel_decoration_v1) {
 		zxdg_toplevel_decoration_v1_destroy(output->zxdg_toplevel_decoration_v1);
 	}
@@ -558,10 +594,11 @@ struct wlr_output *wlr_wl_output_create(struct wlr_backend *wlr_backend) {
 			&xdg_toplevel_listener, output);
 	wl_surface_commit(output->surface);
 
-	output->egl_window = wl_egl_window_create(output->surface,
-			wlr_output->width, wlr_output->height);
-	output->egl_surface = wlr_egl_create_surface(&backend->egl,
-		output->egl_window);
+	output->swapchain = wlr_swapchain_create(output->backend->allocator,
+		wlr_output->width, wlr_output->height, output->backend->format);
+	if (output->swapchain == NULL) {
+		goto error;
+	}
 
 	wl_display_roundtrip(output->backend->remote_display);
 

include/backend/wayland.h

@@ -25,6 +25,8 @@ struct wlr_wl_backend {
 	struct wl_list outputs;
 	struct wlr_egl egl;
 	struct wlr_renderer *renderer;
+	struct wlr_drm_format *format;
+	struct wlr_allocator *allocator;
 	size_t requested_outputs;
 	size_t last_output_num;
 	struct wl_listener local_display_destroy;
@@ -67,10 +69,11 @@ struct wlr_wl_output {
 	struct xdg_surface *xdg_surface;
 	struct xdg_toplevel *xdg_toplevel;
 	struct zxdg_toplevel_decoration_v1 *zxdg_toplevel_decoration_v1;
-	struct wl_egl_window *egl_window;
-	EGLSurface egl_surface;
 	struct wl_list presentation_feedbacks;
 
+	struct wlr_swapchain *swapchain;
+	struct wlr_buffer *back_buffer;
+
 	uint32_t enter_serial;
 
 	struct {