From f7c0a9a62f8a3f009dea9d804ba7921a263fd6af Mon Sep 17 00:00:00 2001
From: boyska <piuttosto@logorroici.org>
Date: Fri, 6 Jan 2017 00:55:17 +0100
Subject: [PATCH] refactor code that get more distant points

---
 lines.cpp | 65 ++++++++++++++++++++++++++++---------------------------
 1 file changed, 33 insertions(+), 32 deletions(-)

diff --git a/lines.cpp b/lines.cpp
index e5d0bd8..0e9f68f 100644
--- a/lines.cpp
+++ b/lines.cpp
@@ -5,6 +5,34 @@ auto WHITE = cv::Scalar(255,255,255);
 auto BLUE = cv::Scalar(200,10,10);
 auto MAGENTA = cv::Scalar(110,10,200);
 
+// takes the two points that are more distant from the next, ie:
+// i st distance(hull[i], hull[i+1]) is maximum and 2nd maximum
+int* max2_distance(std::vector<cv::Point> hull)
+{
+	int *idx = (int*) calloc(2, sizeof(int));
+	int distance[2];
+	for( unsigned i=0; hull.size()>i; i++ )
+	{
+		cv::Point thispoint=hull[i];
+		cv::Point nextpoint=hull[(i+1)%hull.size()];
+		int d=pow(thispoint.x-nextpoint.x,2)+pow(thispoint.y-nextpoint.y,2);
+		if( d>distance[0] ) //the biggest till now
+		{
+			idx[1]=idx[0];
+			idx[0]=i;
+			distance[1]=distance[0];
+			distance[0]=d;
+		}
+		else if( d>distance[1] ) // it is the second biggest till now
+		{
+			idx[1]=i;
+			distance[1]=d;
+		}
+	}
+
+	return idx;
+}
+
 int main(int argc, char *argv[])
 {
 	char const *fname = "files/masckera.png";
@@ -37,7 +65,6 @@ int main(int argc, char *argv[])
 		// choosing the biggest contour in the image
 		// you can test it with files/2contours.png
 		for(auto cont: contours) {
-			std::cout << " - " << cont.size() << std::endl;
 			if(cont.size() > contour.size())
 				contour = cont;
 		}
@@ -46,40 +73,14 @@ int main(int argc, char *argv[])
 	std::vector<cv::Point> hull;
 	cv::convexHull(cv::Mat(contour),hull,false);
 
-	// takes the two points that are more distant from the next, ie:
-	// i st distance(hull[i], hull[i+1]) is maximum and 2nd maximum
-	int idx[2]={0};
-	int distance[2]={0};
-	for( unsigned i=0; hull.size()>i; i++ )
-	{
-		cv::Point thispoint=hull[i];
-		cv::Point nextpoint=hull[(i+1)%hull.size()];
-		int d=pow(thispoint.x-nextpoint.x,2)+pow(thispoint.y-nextpoint.y,2);
-		if( d>distance[0] ) //the biggest till now
-		{
-			idx[1]=idx[0];
-			idx[0]=i;
-			distance[1]=distance[0];
-			distance[0]=d;
-		}
-		else if( d>distance[1] ) // it is the second biggest till now
-		{
-			idx[1]=i;
-			distance[1]=d;
-		}
-	}
-
-
-	std::cout
-		<< "(" << idx[0] << "," << distance[0] << ") -- "
-		<< "(" << idx[1] << "," << distance[1] << ")" << std::endl;
+	int *maxdistances = max2_distance(hull);
 
 	//img = cv::imread(fname,CV_LOAD_IMAGE_COLOR); // uncomment to this to display image with colors
 	unsigned short dotwidth = img.cols >> 6;  // divide by 64, so efficient
-	cv::circle(img,hull[idx[0]],dotwidth,MAGENTA,-1);
-	cv::circle(img,hull[(idx[0]+1)%hull.size()],dotwidth,MAGENTA,-1);
-	cv::circle(img,hull[idx[1]],dotwidth>>1,BLUE,-1);
-	cv::circle(img,hull[(idx[1]+1)%hull.size()],dotwidth>>1,BLUE,-1);
+	cv::circle(img,hull[maxdistances[0]],dotwidth,MAGENTA,-1);
+	cv::circle(img,hull[(maxdistances[0]+1)%hull.size()],dotwidth,MAGENTA,-1);
+	cv::circle(img,hull[maxdistances[1]],dotwidth>>1,BLUE,-1);
+	cv::circle(img,hull[(maxdistances[1]+1)%hull.size()],dotwidth>>1,BLUE,-1);
 	
 	cv::namedWindow("4 corners",CV_WINDOW_NORMAL);
 	cv::imshow("4 corners",img);