ros-noetic-costmap-converter.patch

From cb6af72f331a881fb399e651d6c9aaaf536a63e3 Mon Sep 17 00:00:00 2001
From: Ben Wolsieffer <benwolsieffer@gmail.com>
Date: Thu, 10 Aug 2023 13:29:02 -0400
Subject: [PATCH] Make BlobDetector inherit from cv::Feature2D

BlobDetector currently inherits from cv::SimpleBlobDetector, which is an
interface class that doesn't provide any functionality itself. On the
other hand, every time OpenCV adds a new pure virtual method to this
interface, it breaks BlobDetector.

This patch makes BlobDetector inherit from cv::Feature2D instead, which
should hopefully have fewer breaking changes. This requires adding a
typedef for Params, which was originally provided by
cv::SimpleBlobDetector. I also took the opportunity to make all the
parameters reference this typedef rather than directly use
cv::SimpleBlobDetector::Params.

It is likely possible to remove inheritance from BlobDetector altogether,
since it doesn't appear to use any functionality from cv::Feature2D
either, but I decided not to do this because BlobDetector is part of the
public interface, and this could increase the likelihood of breaking
downstream packages that use this class (if any do).
---
 .../costmap_to_dynamic_obstacles/blob_detector.h       | 10 ++++++----
 src/costmap_to_dynamic_obstacles/blob_detector.cpp     |  4 ++--
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/include/costmap_converter/costmap_to_dynamic_obstacles/blob_detector.h b/include/costmap_converter/costmap_to_dynamic_obstacles/blob_detector.h
index ac9b80a..9bfe5bf 100644
--- a/include/costmap_converter/costmap_to_dynamic_obstacles/blob_detector.h
+++ b/include/costmap_converter/costmap_to_dynamic_obstacles/blob_detector.h
@@ -57,14 +57,16 @@
  *
  * See http://docs.opencv.org/trunk/d0/d7a/classcv_1_1SimpleBlobDetector.html for the original class.
  */
-class BlobDetector : public cv::SimpleBlobDetector
+class BlobDetector : public cv::Feature2D
 {
 public:
+  typedef cv::SimpleBlobDetector::Params Params;
+
   //! Default constructor which optionally accepts custom parameters
-  BlobDetector(const cv::SimpleBlobDetector::Params& parameters = cv::SimpleBlobDetector::Params());
+  BlobDetector(const Params& parameters = Params());
 
   //! Create shared instance of the blob detector with given parameters
-  static cv::Ptr<BlobDetector> create(const BlobDetector::Params& params);
+  static cv::Ptr<BlobDetector> create(const Params& params);
 
   /**
    * @brief Detects keypoints in an image and extracts contours
@@ -90,7 +92,7 @@ class BlobDetector : public cv::SimpleBlobDetector
   const std::vector<std::vector<cv::Point>>& getContours() { return contours_; }
 
   //! Update internal parameters
-  void updateParameters(const cv::SimpleBlobDetector::Params& parameters);
+  void updateParameters(const Params& parameters);
 
 protected:
   struct Center
diff --git a/src/costmap_to_dynamic_obstacles/blob_detector.cpp b/src/costmap_to_dynamic_obstacles/blob_detector.cpp
index c7352f4..564cb0c 100755
--- a/src/costmap_to_dynamic_obstacles/blob_detector.cpp
+++ b/src/costmap_to_dynamic_obstacles/blob_detector.cpp
@@ -2,9 +2,9 @@
 #include <opencv2/opencv.hpp>
 #include <iostream>
 
-BlobDetector::BlobDetector(const SimpleBlobDetector::Params& parameters) : params_(parameters) {}
+BlobDetector::BlobDetector(const Params& parameters) : params_(parameters) {}
 
-cv::Ptr<BlobDetector> BlobDetector::create(const cv::SimpleBlobDetector::Params& params)
+cv::Ptr<BlobDetector> BlobDetector::create(const Params& params)
 {
   return cv::Ptr<BlobDetector> (new BlobDetector(params)); // compatibility with older versions
   //return cv::makePtr<BlobDetector>(params);