From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69924C3A59E for ; Mon, 2 Sep 2019 12:29:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3F8FF20820 for ; Mon, 2 Sep 2019 12:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731608AbfIBM3D (ORCPT ); Mon, 2 Sep 2019 08:29:03 -0400 Received: from mga02.intel.com ([134.134.136.20]:4185 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729984AbfIBM3D (ORCPT ); Mon, 2 Sep 2019 08:29:03 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Sep 2019 05:29:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,459,1559545200"; d="scan'208";a="176308892" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by orsmga008.jf.intel.com with SMTP; 02 Sep 2019 05:28:59 -0700 Received: by stinkbox (sSMTP sendmail emulation); Mon, 02 Sep 2019 15:28:58 +0300 Date: Mon, 2 Sep 2019 15:28:58 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Sidong Yang Cc: Rodrigo Siqueira , David Airlie , Haneen Mohammed , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm/vkms: Use alpha value to blend values. Message-ID: <20190902122858.GU7482@intel.com> References: <20190831172546.GA1972@raspberrypi> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190831172546.GA1972@raspberrypi> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Aug 31, 2019 at 06:25:46PM +0100, Sidong Yang wrote: > Use alpha value to blend source value and destination value Instead of > just overwrite with source value. > > Signed-off-by: Sidong Yang > --- > drivers/gpu/drm/vkms/vkms_composer.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c > index d5585695c64d..b776185e5cb5 100644 > --- a/drivers/gpu/drm/vkms/vkms_composer.c > +++ b/drivers/gpu/drm/vkms/vkms_composer.c > @@ -75,6 +75,9 @@ static void blend(void *vaddr_dst, void *vaddr_src, > int y_limit = y_src + h_dst; > int x_limit = x_src + w_dst; > > + u8 *src, *dst; > + u32 alpha, inv_alpha; These could all live in a tighter scope. Apart from that lgtm Reviewed-by: Ville Syrjälä > + > for (i = y_src, i_dst = y_dst; i < y_limit; ++i) { > for (j = x_src, j_dst = x_dst; j < x_limit; ++j) { > offset_dst = dest_composer->offset > @@ -84,8 +87,14 @@ static void blend(void *vaddr_dst, void *vaddr_src, > + (i * src_composer->pitch) > + (j * src_composer->cpp); > > - memcpy(vaddr_dst + offset_dst, > - vaddr_src + offset_src, sizeof(u32)); > + src = vaddr_src + offset_src; > + dst = vaddr_dst + offset_dst; > + alpha = src[3] + 1; > + inv_alpha = 256 - src[3]; > + dst[0] = (alpha * src[0] + inv_alpha * dst[0]) >> 8; > + dst[1] = (alpha * src[1] + inv_alpha * dst[1]) >> 8; > + dst[2] = (alpha * src[2] + inv_alpha * dst[2]) >> 8; > + dst[3] = 0xff; > } > i_dst++; > } > -- > 2.20.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Ville Syrjälä Intel