From patchwork Thu Jan 23 19:15:34 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 13948568 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3A761C0218D for ; Thu, 23 Jan 2025 19:17:15 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tb2gq-00080h-3s; Thu, 23 Jan 2025 14:16:32 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tb2gJ-0007xu-P7 for qemu-devel@nongnu.org; Thu, 23 Jan 2025 14:16:01 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tb2gI-0003Cr-8e for qemu-devel@nongnu.org; Thu, 23 Jan 2025 14:15:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1737659756; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z4idOmdaT2Lwr+HmD5ha5reAkr+A38GhsY764Z9KdUw=; b=hVnoCmibeVcCZdKQCj5EmqVIssg4RKBBD6yMpuEwbI/caTPTpCkAFD33RIeXxkJP3f+hy6 GcUkKGg4K5ANql++tyKvlQyxzSY6jRdd6uV/FwGalZFkcelGDzbOF/SGyotH9ZT/Q6Tjjd p5thsb7mTYmLUEa0dkLWWPrqW+cm9ro= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-114-5_8EwfKSNxyP7Zr-CiQHrQ-1; Thu, 23 Jan 2025 14:15:54 -0500 X-MC-Unique: 5_8EwfKSNxyP7Zr-CiQHrQ-1 X-Mimecast-MFC-AGG-ID: 5_8EwfKSNxyP7Zr-CiQHrQ Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2FE46195608B for ; Thu, 23 Jan 2025 19:15:53 +0000 (UTC) Received: from toolbx.redhat.com (unknown [10.42.28.222]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id D8B163003FD3; Thu, 23 Jan 2025 19:15:50 +0000 (UTC) From: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: Gerd Hoffmann , "Michael S. Tsirkin" , =?utf-8?q?Marc-Andr=C3=A9_Lureau?= , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= Subject: [RFC 4/6] ui/vnc: pre-multiply alpha with alpha cursor Date: Thu, 23 Jan 2025 19:15:34 +0000 Message-ID: <20250123191536.142753-5-berrange@redhat.com> In-Reply-To: <20250123191536.142753-1-berrange@redhat.com> References: <20250123191536.142753-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -50 X-Spam_score: -5.1 X-Spam_bar: ----- X-Spam_report: (-5.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.996, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.043, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The RFB specification for the alpha cursor encoding requires that the alpha channel is pre-multiplied into the RGB components. This worked by luck previously since the virtio-gpu device was not reversing the pre-multiplication on data received from the guest. Now virtio-gpu is fixed, the VNC server must apply pre-multiplication itself. Signed-off-by: Daniel P. Berrangé --- ui/vnc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/ui/vnc.c b/ui/vnc.c index 9241caaad9..5ffb50109d 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -996,6 +996,7 @@ static int vnc_cursor_define(VncState *vs) } if (vnc_has_feature(vs, VNC_FEATURE_ALPHA_CURSOR)) { + g_autoptr(QEMUCursor) tmpc = cursor_copy(c); vnc_lock_output(vs); vnc_write_u8(vs, VNC_MSG_SERVER_FRAMEBUFFER_UPDATE); vnc_write_u8(vs, 0); /* padding */ @@ -1003,7 +1004,11 @@ static int vnc_cursor_define(VncState *vs) vnc_framebuffer_update(vs, c->hot_x, c->hot_y, c->width, c->height, VNC_ENCODING_ALPHA_CURSOR); vnc_write_s32(vs, VNC_ENCODING_RAW); - vnc_write(vs, c->data, c->width * c->height * 4); + + // Alpha is required to be pre-multiplied into RGB components + cursor_multiply_alpha(tmpc); + + vnc_write(vs, tmpc->data, c->width * c->height * 4); vnc_unlock_output(vs); return 0; }