From 95c65aff75f62407ca1e99bbfa18e2d54322aab5 Mon Sep 17 00:00:00 2001 From: John Smith Date: Fri, 19 Jul 2019 14:07:09 +0200 Subject: [PATCH] Fix cv::selectROI rectangle rendering issue --- modules/highgui/src/roiSelector.cpp | 36 ++++++++++++++++++++++++------------ 1 file changed, 24 insertions(+), 12 deletions(-) diff --git a/modules/highgui/src/roiSelector.cpp b/modules/highgui/src/roiSelector.cpp index d8ca580..4fba07e 100644 --- a/modules/highgui/src/roiSelector.cpp +++ b/modules/highgui/src/roiSelector.cpp @@ -106,10 +106,10 @@ class ROISelector bool isDrawing; Rect2d box; Mat image; + Point2f startPos; // parameters for drawing from the center bool drawFromCenter; - Point2f center; // initializer list handlerT() : isDrawing(false), drawFromCenter(true){}; @@ -136,19 +136,31 @@ class ROISelector { if (selectorParams.drawFromCenter) { - selectorParams.box.width = 2 * (x - selectorParams.center.x); - selectorParams.box.height = 2 * (y - selectorParams.center.y); - selectorParams.box.x = std::min( - std::max(selectorParams.center.x - selectorParams.box.width / 2.0, 0.), (double)imageSize.width); - selectorParams.box.y = std::min( - std::max(selectorParams.center.y - selectorParams.box.height / 2.0, 0.), (double)imageSize.height); + // limit half extends to imageSize + float halfWidth = std::min(std::min( + std::abs(x - selectorParams.startPos.x), + selectorParams.startPos.x), + imageSize.width - selectorParams.startPos.x); + float halfHeight = std::min(std::min( + std::abs(y - selectorParams.startPos.y), + selectorParams.startPos.y), + imageSize.height - selectorParams.startPos.y); + + selectorParams.box.width = halfWidth * 2; + selectorParams.box.height = halfHeight * 2; + selectorParams.box.x = selectorParams.startPos.x - halfWidth; + selectorParams.box.y = selectorParams.startPos.y - halfHeight; + } else { - selectorParams.box.width = std::max( - std::min(x - selectorParams.box.x, (double)imageSize.width - selectorParams.box.x), - selectorParams.box.x); - selectorParams.box.height = std::max( - std::min(y - selectorParams.box.y, (double)imageSize.height - selectorParams.box.y), - selectorParams.box.y); + // limit x and y to imageSize + int lx = std::min(std::max(x, 0), imageSize.width); + int by = std::min(std::max(y, 0), imageSize.height); + selectorParams.box.width = std::abs(lx - selectorParams.startPos.x); + selectorParams.box.height = std::abs(by - selectorParams.startPos.y); + selectorParams.box.x = std::min((float)lx, selectorParams.startPos.x); + selectorParams.box.y = std::min((float)by, selectorParams.startPos.y); } } break; @@ -157,7 +169,7 @@ class ROISelector case EVENT_LBUTTONDOWN: selectorParams.isDrawing = true; selectorParams.box = Rect2d(x, y, 0, 0); - selectorParams.center = Point2f((float)x, (float)y); + selectorParams.startPos = Point2f((float)x, (float)y); break; // cleaning up the selected bounding box -- 2.7.4