From nobody Fri Oct 24 22:14:59 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1518782193341458.8648605869281; Fri, 16 Feb 2018 03:56:33 -0800 (PST) Received: from localhost ([::1]:40509 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1emecw-0002y8-9c for importer@patchew.org; Fri, 16 Feb 2018 06:56:30 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36360) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1emeao-0001dP-Pg for qemu-devel@nongnu.org; Fri, 16 Feb 2018 06:54:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1emeal-0003ff-JR for qemu-devel@nongnu.org; Fri, 16 Feb 2018 06:54:18 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:33016 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1emeal-0003eO-DL for qemu-devel@nongnu.org; Fri, 16 Feb 2018 06:54:15 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A84CC407519B; Fri, 16 Feb 2018 11:54:13 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-116-147.ams2.redhat.com [10.36.116.147]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4DB85D1BA7; Fri, 16 Feb 2018 11:54:11 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id C28304F29E; Fri, 16 Feb 2018 12:54:10 +0100 (CET) From: Gerd Hoffmann To: qemu-devel@nongnu.org Date: Fri, 16 Feb 2018 12:54:05 +0100 Message-Id: <20180216115410.27287-5-kraxel@redhat.com> In-Reply-To: <20180216115410.27287-1-kraxel@redhat.com> References: <20180216115410.27287-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Fri, 16 Feb 2018 11:54:13 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Fri, 16 Feb 2018 11:54:13 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'kraxel@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PULL 4/9] sdl: restore optimized redraw X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gerd Hoffmann , Anatoly Trosinenko Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Anatoly Trosinenko The documentation on SDL_RenderPresent function states that "the backbuffer should be considered invalidated after each present", so copy the entire texture on each redraw. On the other hand, SDL_UpdateTexture function is described as "fairly slow function", so restrict it to just the changed pixels. Also added SDL_RenderClear call, as suggested in the documentation page on SDL_RenderPresent. Signed-off-by: Anatoly Trosinenko Message-id: 20180205133228.25082-1-anatoly.trosinenko@gmail.com Signed-off-by: Gerd Hoffmann --- ui/sdl2-2d.c | 21 ++++++--------------- 1 file changed, 6 insertions(+), 15 deletions(-) diff --git a/ui/sdl2-2d.c b/ui/sdl2-2d.c index 8ab68d67b9..1f34817bae 100644 --- a/ui/sdl2-2d.c +++ b/ui/sdl2-2d.c @@ -36,6 +36,8 @@ void sdl2_2d_update(DisplayChangeListener *dcl, struct sdl2_console *scon =3D container_of(dcl, struct sdl2_console, d= cl); DisplaySurface *surf =3D qemu_console_surface(dcl->con); SDL_Rect rect; + size_t surface_data_offset =3D surface_bytes_per_pixel(surf) * x + + surface_stride(surf) * y; =20 assert(!scon->opengl); =20 @@ -46,27 +48,16 @@ void sdl2_2d_update(DisplayChangeListener *dcl, return; } =20 - /* - * SDL2 seems to do some double-buffering, and trying to only - * update the changed areas results in only one of the two buffers - * being updated. Which flickers alot. So lets not try to be - * clever do a full update every time ... - */ -#if 0 rect.x =3D x; rect.y =3D y; rect.w =3D w; rect.h =3D h; -#else - rect.x =3D 0; - rect.y =3D 0; - rect.w =3D surface_width(surf); - rect.h =3D surface_height(surf); -#endif =20 - SDL_UpdateTexture(scon->texture, NULL, surface_data(surf), + SDL_UpdateTexture(scon->texture, &rect, + surface_data(surf) + surface_data_offset, surface_stride(surf)); - SDL_RenderCopy(scon->real_renderer, scon->texture, &rect, &rect); + SDL_RenderClear(scon->real_renderer); + SDL_RenderCopy(scon->real_renderer, scon->texture, NULL, NULL); SDL_RenderPresent(scon->real_renderer); } =20 --=20 2.9.3