From 55b88bc14f149f53a3f801bc87d0960d9388d6ab Mon Sep 17 00:00:00 2001 From: Willow Barraco Date: Thu, 17 Apr 2025 17:58:38 +0200 Subject: [PATCH] Optimize the backporting condition At the moment we flip the two buffers, and we backport the damaged area on every frame callback. We completely ignore the compositor sent event buffer->release. This event means that the compositor finished reading the buffer pixels, and will never read them again. So we can keep using the same buffer instead of fliping, if we receive the event before asking for a new frame callback. The change is not complicated, but we have to distinguish drwsurf_attach, and drwsurf_flip. We try to flip before trying to draw anything. And if the buffer has already been released, we don't flip. We also have to track the backport_damage separately than the buffer current damage. Signed-off-by: Maarten van Gompel --- drw.c | 42 ++++++++++++++++++++++++++++++++++-------- drw.h | 4 +++- main.c | 4 ++-- 3 files changed, 39 insertions(+), 11 deletions(-) diff --git a/drw.c b/drw.c index 2b35961..67b52f5 100644 --- a/drw.c +++ b/drw.c @@ -6,6 +6,15 @@ #include "shm_open.h" #include "math.h" +void drwbuf_handle_release(void *data, struct wl_buffer *wl_buffer) { + struct drwbuf *db = data; + db->released = true; +}; + +const struct wl_buffer_listener buffer_listener = { + .release = drwbuf_handle_release +}; + void drwsurf_handle_frame_cb(void* data, struct wl_callback* callback, uint32_t time) { @@ -18,8 +27,9 @@ void drwsurf_handle_frame_cb(void* data, struct wl_callback* callback, cairo_region_get_rectangle(ds->back_buffer->damage, i, &r); wl_surface_damage(ds->surf, r.x, r.y, r.width, r.height); }; + cairo_region_subtract(ds->display_buffer->damage, ds->display_buffer->damage); - drwsurf_flip(ds); + drwsurf_attach(ds); } const struct wl_callback_listener frame_listener = { @@ -41,6 +51,7 @@ void drwsurf_damage(struct drwsurf *ds, uint32_t x, uint32_t y, uint32_t w, uint { cairo_rectangle_int_t rect = { x, y, w, h }; cairo_region_union_rectangle(ds->back_buffer->damage, &rect); + cairo_region_union_rectangle(ds->back_buffer->backport_damage, &rect); drwsurf_register_frame_cb(ds); } @@ -64,8 +75,8 @@ drwsurf_backport(struct drwsurf *ds) cairo_set_operator(ds->back_buffer->cairo, CAIRO_OPERATOR_SOURCE); cairo_rectangle_int_t r = {0}; - for (int i = 0; i < cairo_region_num_rectangles(ds->display_buffer->damage); i++) { - cairo_region_get_rectangle(ds->display_buffer->damage, i, &r); + for (int i = 0; i < cairo_region_num_rectangles(ds->display_buffer->backport_damage); i++) { + cairo_region_get_rectangle(ds->display_buffer->backport_damage, i, &r); cairo_set_source_surface(ds->back_buffer->cairo, ds->display_buffer->cairo_surf, 0, 0); cairo_rectangle( @@ -79,16 +90,23 @@ drwsurf_backport(struct drwsurf *ds) }; cairo_restore(ds->back_buffer->cairo); - cairo_region_subtract(ds->display_buffer->damage, ds->display_buffer->damage); + cairo_region_subtract(ds->display_buffer->backport_damage, ds->display_buffer->backport_damage); +} + +void +drwsurf_attach(struct drwsurf *ds) +{ + wl_surface_attach(ds->surf, ds->back_buffer->buf, 0, 0); + wl_surface_commit(ds->surf); + ds->back_buffer->released = false; + ds->attached = true; } void drwsurf_flip(struct drwsurf *ds) { - wl_surface_attach(ds->surf, ds->back_buffer->buf, 0, 0); - wl_surface_commit(ds->surf); - ds->attached = true; - + if (ds->back_buffer->released) + return; struct drwbuf *tmp = ds->back_buffer; ds->back_buffer = ds->display_buffer; ds->display_buffer = tmp; @@ -101,6 +119,7 @@ drw_draw_text(struct drwsurf *ds, Color color, uint32_t x, uint32_t y, uint32_t w, uint32_t h, uint32_t b, const char *label, PangoFontDescription *font_description) { + drwsurf_flip(ds); struct drwbuf *d = ds->back_buffer; cairo_save(d->cairo); @@ -128,6 +147,7 @@ drw_draw_text(struct drwsurf *ds, Color color, uint32_t x, uint32_t y, void drw_do_clear(struct drwsurf *ds, uint32_t x, uint32_t y, uint32_t w, uint32_t h) { + drwsurf_flip(ds); struct drwbuf *d = ds->back_buffer; cairo_save(d->cairo); @@ -143,6 +163,7 @@ void drw_do_rectangle(struct drwsurf *ds, Color color, uint32_t x, uint32_t y, uint32_t w, uint32_t h, bool over, int rounding) { + drwsurf_flip(ds); struct drwbuf *d = ds->back_buffer; cairo_save(d->cairo); @@ -229,6 +250,8 @@ setup_buffer(struct drwsurf *drwsurf, struct drwbuf *drwbuf) stride, WL_SHM_FORMAT_ARGB8888); wl_shm_pool_destroy(pool); close(fd); + wl_buffer_add_listener(drwbuf->buf, &buffer_listener, drwbuf); + drwbuf->released = true; if (drwbuf->cairo_surf) @@ -240,6 +263,9 @@ setup_buffer(struct drwsurf *drwsurf, struct drwbuf *drwbuf) if (drwbuf->damage) cairo_region_destroy(drwbuf->damage); drwbuf->damage = cairo_region_create(); + if (drwbuf->backport_damage) + cairo_region_destroy(drwbuf->backport_damage); + drwbuf->backport_damage = cairo_region_create(); if (drwbuf->cairo) cairo_destroy(drwbuf->cairo); diff --git a/drw.h b/drw.h index dac675f..1fd6bc1 100644 --- a/drw.h +++ b/drw.h @@ -10,11 +10,12 @@ struct drw { struct drwbuf { uint32_t size; struct wl_buffer *buf; - cairo_region_t *damage; + cairo_region_t *damage, *backport_damage; cairo_surface_t *cairo_surf; cairo_t *cairo; PangoLayout *layout; unsigned char *pool_data; + bool released; }; struct drwsurf { uint32_t width, height; @@ -34,6 +35,7 @@ struct kbd; void drwsurf_damage(struct drwsurf *ds, uint32_t x, uint32_t y, uint32_t w, uint32_t h); void drwsurf_resize(struct drwsurf *ds, uint32_t w, uint32_t h, double s); +void drwsurf_attach(struct drwsurf *ds); void drwsurf_flip(struct drwsurf *ds); typedef union { diff --git a/main.c b/main.c index 972e640..2b65e0b 100644 --- a/main.c +++ b/main.c @@ -517,7 +517,7 @@ xdg_popup_surface_configure(void *data, struct xdg_surface *xdg_surface, { xdg_surface_ack_configure(xdg_surface, serial); popup_xdg_surface_configured = true; - drwsurf_flip(&popup_draw_surf); + drwsurf_attach(&popup_draw_surf); } static const struct xdg_surface_listener xdg_popup_surface_listener = { @@ -664,7 +664,7 @@ layer_surface_configure(void *data, struct zwlr_layer_surface_v1 *surface, zwlr_layer_surface_v1_ack_configure(surface, serial); kbd_resize(&keyboard, layouts, NumLayouts); - drwsurf_flip(&draw_surf); + drwsurf_attach(&draw_surf); } else { zwlr_layer_surface_v1_ack_configure(surface, serial); }