Explicitly use double precision sin & cos in hough implementation

Andrey Kamaev · Andrey Kamaev · commit 16687a265546 · 2012-12-25T18:05:05.000+04:00
On some platforms sin and cos are calculated in single precision resulting in
diversity of results.
diff --git a/modules/imgproc/src/hough.cpp b/modules/imgproc/src/hough.cpp
@@ -118,8 +118,8 @@ icvHoughLinesStandard( const CvMat* img, float rho, float theta,
     float ang = 0;
     for(int n = 0; n < numangle; ang += theta, n++ )
     {
-        tabSin[n] = (float)(sin(ang) * irho);
-        tabCos[n] = (float)(cos(ang) * irho);
+        tabSin[n] = (float)(sin((double)ang) * irho);
+        tabCos[n] = (float)(cos((double)ang) * irho);
     }
 
     // stage 1. fill accumulator

Original file line number	Diff line number	Diff line change
`@@ -118,8 +118,8 @@ icvHoughLinesStandard( const CvMat* img, float rho, float theta,`
`118`	`118`	`float ang = 0;`
`119`	`119`	`for(int n = 0; n < numangle; ang += theta, n++ )`
`120`	`120`	`{`
`121`		`- tabSin[n] = (float)(sin(ang) * irho);`
`122`		`- tabCos[n] = (float)(cos(ang) * irho);`
	`121`	`+ tabSin[n] = (float)(sin((double)ang) * irho);`
	`122`	`+ tabCos[n] = (float)(cos((double)ang) * irho);`
`123`	`123`	`}`
`124`	`124`
`125`	`125`	`// stage 1. fill accumulator`