From cf1eb0250707fe271d1ce41c2cedb162051beb1c Mon Sep 17 00:00:00 2001
From: Phuntsok Drak-pa <phundrak@phundrak.fr>
Date: Thu, 25 Apr 2019 02:53:53 +0200
Subject: [PATCH] less raw for-loops

---
 src/methods.cc | 44 +++++++++++++++++++-------------------------
 1 file changed, 19 insertions(+), 25 deletions(-)

diff --git a/src/methods.cc b/src/methods.cc
index 4cc9f1a..ada5a0e 100644
--- a/src/methods.cc
+++ b/src/methods.cc
@@ -294,9 +294,8 @@ void ImageManipulator::get_color_set()
 			thread_list.push_back(
 			    std::thread(&ImageManipulator::threaded_get_color, this, h + i));
 		}
-		for (auto& th : thread_list) {
-			th.join();
-		}
+		std::for_each(thread_list.begin(), thread_list.end(),
+		              [](auto& th) { th.join(); });
 	}
 	colors_.shrink_to_fit();
 }
@@ -339,12 +338,11 @@ void ImageManipulator::draw_square(cv::Mat& t_img,
                                    int const t_size,
                                    cv::Scalar const& t_color) const
 {
-	auto points = std::make_unique<cv::Point[]>(4);
-	points[0] = t_top_left;
-	points[1] = cv::Point{t_top_left.x, t_top_left.y + t_size};
-	points[2] = cv::Point{t_top_left.x + t_size, t_top_left.y + t_size};
-	points[3] = cv::Point{t_top_left.x + t_size, t_top_left.y};
-	fillConvexPoly(t_img, points.get(), 4, t_color);
+	std::array<cv::Point, 4> points
+	    = {t_top_left, cv::Point{t_top_left.x, t_top_left.y + t_size},
+	       cv::Point{t_top_left.x + t_size, t_top_left.y + t_size},
+	       cv::Point{t_top_left.x + t_size, t_top_left.y}};
+	fillConvexPoly(t_img, points.data(), 4, t_color);
 }
 
 /**
@@ -406,8 +404,6 @@ void ImageManipulator::method1()
 void ImageManipulator::method2()
 {
 	spdlog::debug("Beginning method2, initial difference: {}", diff_);
-	spdlog::debug("nb_total_iter: {}, nb_remaining_iter: {}", total_iterations_,
-	              remaining_iter_);
 	spdlog::debug("Running on {} threads", thread_nbr);
 	get_color_set();
 	spdlog::debug("{} colors detected", colors_.size());
@@ -421,8 +417,6 @@ void ImageManipulator::method2()
 void ImageManipulator::method3()
 {
 	spdlog::debug("Beginning method3, initial difference: {}", diff_);
-	spdlog::debug("nb_total_iter: {}, nb_remaining_iter: {}", total_iterations_,
-	              remaining_iter_);
 	spdlog::debug("Running on {} threads", thread_nbr);
 	get_color_set();
 	spdlog::debug("{} colors detected", colors_.size());
@@ -440,8 +434,6 @@ void ImageManipulator::method3()
 void ImageManipulator::method4(bool const t_controlled_size)
 {
 	spdlog::debug("Beginning method4, initial difference: {}", diff_);
-	spdlog::debug("nb_total_iter: {}, nb_remaining_iter: {}", total_iterations_,
-	              remaining_iter_);
 	spdlog::debug("Running on {} threads", thread_nbr);
 	get_color_set();
 	spdlog::debug("{} colors detected", colors_.size());
@@ -449,16 +441,19 @@ void ImageManipulator::method4(bool const t_controlled_size)
 		std::vector<std::future<std::optional<std::pair<cv::Mat, double>>>>
 		    results{};
 		std::vector<std::pair<cv::Mat, double>> values{};
+		// launch asynchronously candidate image generation
 		for (size_t i = 0; i < thread_nbr; ++i) {
 			results.push_back(std::async(std::launch::async,
 			                             &ImageManipulator::create_candidate, this,
 			                             t_controlled_size));
 		}
-		for (auto& elem : results) {
-			if (auto res = elem.get(); res.has_value() && res->second < diff_) {
+		// if candidate is a success, store it
+		std::for_each(results.begin(), results.end(), [&values, this](auto& elem) {
+			if (auto res = elem.get(); res.has_value() && res->second < this->diff_) {
 				values.push_back(*res);
 			}
-		}
+		});
+		// apply best candidate
 		if (values.size() > 0) {
 			auto const pos
 			    = std::min_element(std::begin(values), std::end(values),
@@ -488,14 +483,13 @@ void ImageManipulator::method5(bool const t_controlled_size,
 	spdlog::debug("{} tiles", tiles.size());
 
 	std::vector<std::thread> thread_list{};
-	for (auto& row : tiles) {
-		for (auto& tile : row) {
+	std::for_each(tiles.begin(), tiles.end(), [&](auto& row) {
+		std::for_each(row.begin(), row.end(), [&](auto& tile) {
 			thread_list.emplace_back(
 			    [&]() { tile.exec_method(t_submethod, t_controlled_size); });
-		}
-	}
-	for (auto& th : thread_list) {
-		th.join();
-	}
+		});
+	});
+	std::for_each(thread_list.begin(), thread_list.end(),
+	              [](auto& th) { th.join(); });
 	merge_tiles(tiles);
 }