[{"id":35550,"web_url":"https://patchwork.libcamera.org/comment/35550/","msgid":"<97ba778e-3d2d-4ed8-a28d-5e5aedf9e233@ideasonboard.com>","date":"2025-08-25T11:54:52","subject":"Re: [PATCH] utils: Add unary negation operation to Duration","submitter":{"id":216,"url":"https://patchwork.libcamera.org/api/people/216/","name":"Barnabás Pőcze","email":"barnabas.pocze@ideasonboard.com"},"content":"Hi\n\n2025. 08. 25. 13:46 keltezéssel, Paul Elder írta:\n> In the near future we will add a SyncAdjustment control for adjusting\n> the frame duration via the sync algorithm. This control needs to be able\n> to take on a negative value, since the frame duration can be shortened\n> in addition to being extended. While the control is an int, it would be\n> convenient to be able to clamp it to frame duration limits, which are\n> usually handled as utils::Duration values internally. To allow this\n> using utils::Duration, add a unary negation operation to\n> utils::Duration. Also add a test for the operator.\n> \n> Signed-off-by: Paul Elder \n\nReviewed-by: Barnabás Pőcze \n\n\n> ---\n> include/libcamera/base/utils.h | 5 +++++\n> src/libcamera/base/utils.cpp | 6 ++++++\n> test/utils.cpp | 6 ++++++\n> 3 files changed, 17 insertions(+)\n> \n> diff --git a/include/libcamera/base/utils.h b/include/libcamera/base/utils.h\n> index f21c6dc016ec..cb8caaa9bacc 100644\n> --- a/include/libcamera/base/utils.h\n> +++ b/include/libcamera/base/utils.h\n> @@ -394,6 +394,11 @@ public:\n> \t\treturn c.count();\n> \t}\n> \n> +\tconstexpr Duration operator-() const\n> +\t{\n> +\t\treturn BaseDuration::operator-();\n> +\t}\n> +\n> \texplicit constexpr operator bool() const\n> \t{\n> \t\treturn *this != BaseDuration::zero();\n> diff --git a/src/libcamera/base/utils.cpp b/src/libcamera/base/utils.cpp\n> index bcfc1941a92a..cb9fe0049c83 100644\n> --- a/src/libcamera/base/utils.cpp\n> +++ b/src/libcamera/base/utils.cpp\n> @@ -425,6 +425,12 @@ std::string toAscii(const std::string &str)\n> * \\return The tick count of the Duration expressed in \\a Period\n> */\n> \n> +/**\n> + * \\fn Duration::operator-()\n> + * \\brief Negation operator to negate a \\a Duration\n> + * \\return The duration, with the number of ticks negated\n> + */\n> +\n> /**\n> * \\fn Duration::operator bool()\n> * \\brief Boolean operator to test if a \\a Duration holds a non-zero time value\n> diff --git a/test/utils.cpp b/test/utils.cpp\n> index d25475cb93b9..195fddc97d97 100644\n> --- a/test/utils.cpp\n> +++ b/test/utils.cpp\n> @@ -167,6 +167,12 @@ protected:\n> \t\t\treturn TestFail;\n> \t\t}\n> \n> +\t\texposure = 100ms;\n> +\t\tif ((-exposure).get() != -100) {\n> +\t\t\tcerr << \"utils::Duration failed negation\" << endl;\n> +\t\t\treturn TestFail;\n> +\t\t}\n> +\n> \t\treturn TestPass;\n> \t}\n>","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 55D08BEFBE\n\tfor ;\n\tMon, 25 Aug 2025 11:55:00 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 133E2692ED;\n\tMon, 25 Aug 2025 13:54:59 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 50309692E3\n\tfor ;\n\tMon, 25 Aug 2025 13:54:57 +0200 (CEST)","from [192.168.33.19] (185.182.215.11.nat.pool.zt.hu\n\t[185.182.215.11])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 09BEE13D7;\n\tMon, 25 Aug 2025 13:53:54 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"UrQekR/z\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1756122835;\n\tbh=dj2autkfBPvYRjSZQiIsrwvJ+nD36jElo/9MTz9FiQY=;\n\th=Date:Subject:To:References:From:In-Reply-To:From;\n\tb=UrQekR/zfYHTCvfLU8R9yO9AWsJyXNTC/xsmlDctvkjewXdFzNN3udaGUaS18uAZ0\n\tD1W2Ofjc0hNWzdXv9POvFJZD16Gm9d+tt13m5a4h2mqPUXZ09qhgV4tkUpycSJgH76\n\tAZKDzhHlz3goN8KTDlDRwO35feJEmpZlZz4POBXw=","Message-ID":"<97ba778e-3d2d-4ed8-a28d-5e5aedf9e233@ideasonboard.com>","Date":"Mon, 25 Aug 2025 13:54:52 +0200","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Subject":"Re: [PATCH] utils: Add unary negation operation to Duration","To":"Paul Elder ,\n\tlibcamera-devel@lists.libcamera.org","References":"<20250825114642.576534-1-paul.elder@ideasonboard.com>","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Content-Language":"en-US, hu-HU","In-Reply-To":"<20250825114642.576534-1-paul.elder@ideasonboard.com>","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"8bit","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":35665,"web_url":"https://patchwork.libcamera.org/comment/35665/","msgid":"<175672680348.50296.366034616472606636@ping.linuxembedded.co.uk>","date":"2025-09-01T11:40:03","subject":"Re: [PATCH] utils: Add unary negation operation to Duration","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"Quoting Paul Elder (2025-08-25 12:46:42)\n> In the near future we will add a SyncAdjustment control for adjusting\n> the frame duration via the sync algorithm. This control needs to be able\n> to take on a negative value, since the frame duration can be shortened\n> in addition to being extended. While the control is an int, it would be\n> convenient to be able to clamp it to frame duration limits, which are\n> usually handled as utils::Duration values internally. To allow this\n> using utils::Duration, add a unary negation operation to\n> utils::Duration. Also add a test for the operator.\n> \n> Signed-off-by: Paul Elder \n\nReviewed-by: Kieran Bingham \n\n> ---\n> include/libcamera/base/utils.h | 5 +++++\n> src/libcamera/base/utils.cpp | 6 ++++++\n> test/utils.cpp | 6 ++++++\n> 3 files changed, 17 insertions(+)\n> \n> diff --git a/include/libcamera/base/utils.h b/include/libcamera/base/utils.h\n> index f21c6dc016ec..cb8caaa9bacc 100644\n> --- a/include/libcamera/base/utils.h\n> +++ b/include/libcamera/base/utils.h\n> @@ -394,6 +394,11 @@ public:\n> return c.count();\n> }\n> \n> + constexpr Duration operator-() const\n> + {\n> + return BaseDuration::operator-();\n> + }\n> +\n> explicit constexpr operator bool() const\n> {\n> return *this != BaseDuration::zero();\n> diff --git a/src/libcamera/base/utils.cpp b/src/libcamera/base/utils.cpp\n> index bcfc1941a92a..cb9fe0049c83 100644\n> --- a/src/libcamera/base/utils.cpp\n> +++ b/src/libcamera/base/utils.cpp\n> @@ -425,6 +425,12 @@ std::string toAscii(const std::string &str)\n> * \\return The tick count of the Duration expressed in \\a Period\n> */\n> \n> +/**\n> + * \\fn Duration::operator-()\n> + * \\brief Negation operator to negate a \\a Duration\n> + * \\return The duration, with the number of ticks negated\n> + */\n> +\n> /**\n> * \\fn Duration::operator bool()\n> * \\brief Boolean operator to test if a \\a Duration holds a non-zero time value\n> diff --git a/test/utils.cpp b/test/utils.cpp\n> index d25475cb93b9..195fddc97d97 100644\n> --- a/test/utils.cpp\n> +++ b/test/utils.cpp\n> @@ -167,6 +167,12 @@ protected:\n> return TestFail;\n> }\n> \n> + exposure = 100ms;\n> + if ((-exposure).get() != -100) {\n> + cerr << \"utils::Duration failed negation\" << endl;\n> + return TestFail;\n> + }\n> +\n> return TestPass;\n> }\n> \n> -- \n> 2.47.2\n>","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 8AB17BEFBE\n\tfor ;\n\tMon, 1 Sep 2025 11:40:08 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 2A22A69324;\n\tMon, 1 Sep 2025 13:40:08 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 738E069324\n\tfor ;\n\tMon, 1 Sep 2025 13:40:06 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(cpc89244-aztw30-2-0-cust6594.18-1.cable.virginm.net [86.31.185.195])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 41260E45;\n\tMon, 1 Sep 2025 13:38:59 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"nUyebzBE\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1756726739;\n\tbh=1lYvPAdk9rP8f5NXbHCHMVs75WpHSbI1zIPx2XTEX1w=;\n\th=In-Reply-To:References:Subject:From:Cc:To:Date:From;\n\tb=nUyebzBE96rMF7GPIijMrDHljkj4lwUyit9rcaCjeTDFjdr5d1EcsJexHKf3H8GP6\n\tX73WE4b4FNN+sUkjQ0ngulbAcb2EmO52bMi5roJXdclzPx7OlYTRPaw7nFPtRYQUiQ\n\tzU9PS21gRqqHgDBU4llf9uz5HF6UwWsIW67oUp1A=","Content-Type":"text/plain; charset=\"utf-8\"","MIME-Version":"1.0","Content-Transfer-Encoding":"quoted-printable","In-Reply-To":"<20250825114642.576534-1-paul.elder@ideasonboard.com>","References":"<20250825114642.576534-1-paul.elder@ideasonboard.com>","Subject":"Re: [PATCH] utils: Add unary negation operation to Duration","From":"Kieran Bingham ","Cc":"Paul Elder ","To":"Paul Elder ,\n\tlibcamera-devel@lists.libcamera.org","Date":"Mon, 01 Sep 2025 12:40:03 +0100","Message-ID":"<175672680348.50296.366034616472606636@ping.linuxembedded.co.uk>","User-Agent":"alot/0.9.1","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}}]