From 96f1d1b08db550bd51374c081f8729383a7065a0 Mon Sep 17 00:00:00 2001 From: Daniel van Vugt Date: Wed, 24 Jun 2020 16:00:17 +0800 Subject: [PATCH] st-label: Keep labels fully pre-rendered on the GPU The performance of the icon grid was being hindered by a large number of primitives (a few hundred) being copied from the CPU to the GPU on each frame. This was first noticed in mutter#971 but we failed to investigate all the issues at the time. You can also see the high number using `COGL_DEBUG=batching` or `COGL_DEBUG=disable-texturing`. So now it's obvious that high number is every letter of every label being uploaded as a separate quad. Let's not do that and instead treat the whole label as a single quad/texture. Measured performance on an i7-7700 at UHD 3840x2160: Journal entries per frame on the icon grid: * Before: 288 (18 KB copied from CPU to GPU) * After: 73 ( 4 KB copied from CPU to GPU) Spring animation: * Before: 20-30 FPS, avg 22/peak 45 milliseconds per frame * After: 30-40 FPS, avg 14/peak 28 milliseconds per frame Scrolling the icon grid: * Before: 15 FPS, 50 milliseconds per frame * After: 30 FPS, 28 milliseconds per frame https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1329 (cherry picked from commit ae338af1e80ed89eb624a36a666894c986573c76) --- src/st/st-label.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/st/st-label.c b/src/st/st-label.c index 947c8ec86..3f82a2c15 100644 --- a/src/st/st-label.c +++ b/src/st/st-label.c @@ -294,6 +294,7 @@ st_label_class_init (StLabelClass *klass) static void st_label_init (StLabel *label) { + ClutterActor *actor = CLUTTER_ACTOR (label); StLabelPrivate *priv; label->priv = priv = st_label_get_instance_private (label); @@ -305,7 +306,10 @@ st_label_init (StLabel *label) label->priv->shadow_width = -1.; label->priv->shadow_height = -1.; - clutter_actor_add_child (CLUTTER_ACTOR (label), priv->label); + clutter_actor_add_child (actor, priv->label); + + clutter_actor_set_offscreen_redirect (actor, + CLUTTER_OFFSCREEN_REDIRECT_ALWAYS); } /**