From patchwork Mon Jul 24 07:10:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 18868 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 4C54DBDC71 for ; Mon, 24 Jul 2023 07:11:31 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id F1125628DB; Mon, 24 Jul 2023 09:11:30 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=libcamera.org; s=mail; t=1690182691; bh=de7+2e+c3mVF0ji8CUWyiKapTfOOMPyU2+UAbMj/jMg=; h=To:Date:In-Reply-To:References:Subject:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=MKxZr5UssduDIsP8hv9NxlqzZDLcU7ZXP+N+uM6zfe8nFqXGll4/8dNGH+gD9jEPM xHA8+zahDtf6Tukx3/fyY0/FlHp7242aLMQfC1P0tmoGhRl7k5jay8lJKqEgxOJ7Tg Ykkm5mO4QmfZ6ErkrHFZSf5KMWWICND0+wUuRnPZBEMKVsTZE+FxNmi8p0K6b3ITeE mEh5EZEacRdYTHC1dRuhPUKG6M38v35WsZjZQszdlqxbmNdgbhL69zSh7dkKJgkLEV IINcFHjteYVpBX94fIQqnMLt4jsDM3ZKIoFMT/czRqbsrs3b8yoQJzLFTtsyWAIZRH odcfdkCn2i5fw== Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 242DC628C0 for ; Mon, 24 Jul 2023 09:11:25 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="BR8P++4y"; dkim-atps=neutral Received: from uno.localdomain (mob-5-91-20-233.net.vodafone.it [5.91.20.233]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 345EF2C6; Mon, 24 Jul 2023 09:10:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1690182627; bh=de7+2e+c3mVF0ji8CUWyiKapTfOOMPyU2+UAbMj/jMg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BR8P++4ymW4U4xqOU27LxJD7XeRdOJaq9cS3NJ/IO42daq50ak8oYQHfJG7M/0hm9 5gOFjAuqev2XRMCp1mGDSApAvl7kaM/Rb1c+6PQ6FZruB/ivud8fiOslHn9ue934En FMvlEea8UjWq1DsPBc3EkFVPTvZJozDGDekNbEcE= To: libcamera-devel@lists.libcamera.org Date: Mon, 24 Jul 2023 09:10:57 +0200 Message-Id: <20230724071101.5256-7-jacopo.mondi@ideasonboard.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230724071101.5256-1-jacopo.mondi@ideasonboard.com> References: <20230724071101.5256-1-jacopo.mondi@ideasonboard.com> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v4 06/10] libcamera: transform: Invert operator*() operands X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Jacopo Mondi via libcamera-devel From: Jacopo Mondi Reply-To: Jacopo Mondi Cc: Jacopo Mondi Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" The current definition of operator*(Transform t1, Transform t0) follows the function composition notion, where t0 is applied first then t1 is applied last. In order to introduce operator*(Orientation, Transform) where a Transform is applied on top of an Orientation, invert the operand order of operator*(Transform, Transform) so that usage of operator* with both Orientation and Transform can be made associative. For example: Orientation o; Transform t = t1 * t2 Orientation o1 = o * t = o * (t1 * t2) = (o * t1) * t2 = o * t1 * t2 Signed-off-by: Jacopo Mondi Reviewed-by: David Plowman --- src/libcamera/camera_sensor.cpp | 4 ++-- src/libcamera/transform.cpp | 19 +++++++++++-------- 2 files changed, 13 insertions(+), 10 deletions(-) diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp index 3ba364c44a40..038d8b959072 100644 --- a/src/libcamera/camera_sensor.cpp +++ b/src/libcamera/camera_sensor.cpp @@ -1051,7 +1051,7 @@ Transform CameraSensor::validateTransform(Transform *transform) const * Combine the requested transform to compensate the sensor mounting * rotation. */ - Transform combined = *transform * rotationTransform_; + Transform combined = rotationTransform_ * *transform; /* * We combine the platform and user transform, but must "adjust away" @@ -1080,7 +1080,7 @@ Transform CameraSensor::validateTransform(Transform *transform) const * If the sensor can do no transforms, then combined must be * changed to the identity. The only user transform that gives * rise to this is the inverse of the rotation. (Recall that - * combined = transform * rotationTransform.) + * combined = rotationTransform * transform.) */ *transform = -rotationTransform_; combined = Transform::Identity; diff --git a/src/libcamera/transform.cpp b/src/libcamera/transform.cpp index c70cac3f14ee..d192d63d9290 100644 --- a/src/libcamera/transform.cpp +++ b/src/libcamera/transform.cpp @@ -189,14 +189,17 @@ Input image | | goes to output image | | */ /** - * \brief Compose two transforms together - * \param[in] t1 The second transform - * \param[in] t0 The first transform + * \brief Compose two transforms by applying \a t0 first then \a t1 + * \param[in] t0 The first transform to apply + * \param[in] t1 The second transform to apply + * + * Compose two transforms by applying \a t1 after \a t0. The operation + * is conceptually equivalent to the canonical notion of function composition, + * with inverse order of operands. If in the canonical function composition + * notation "f * g" equals to "f(g())", the notation for Transforms composition + * "t0 * t1" equals to "t1(t0()))" where \a t0 is applied first, then \a t1. * - * Composing transforms follows the usual mathematical convention for - * composing functions. That is, when performing `t1 * t0`, \a t0 is applied - * first, and then \a t1. - * For example, `Transpose * HFlip` performs `HFlip` first and then the + * For example, `HFlip * Transpose` performs `HFlip` first and then the * `Transpose` yielding `Rot270`, as shown below. ~~~ A-B B-A B-D @@ -206,7 +209,7 @@ Input image | | -> HFLip -> | | -> Transpose -> | | = Rot270 * Note that composition is generally non-commutative for Transforms, * and not the same as XOR-ing the underlying bit representations. */ -Transform operator*(Transform t1, Transform t0) +Transform operator*(Transform t0, Transform t1) { /* * Reorder the operations so that we imagine doing t0's transpose