fixed #648 (build error without OctoMap dependency)

corelib/src/util2d.cpp

@@ -2044,6 +2044,55 @@ cv::Mat exposureFusion(const std::vector<cv::Mat> & images)
 	return fusion;
 }
 
+void HSVtoRGB( float *r, float *g, float *b, float h, float s, float v )
+{
+	int i;
+	float f, p, q, t;
+	if( s == 0 ) {
+		// achromatic (grey)
+		*r = *g = *b = v;
+		return;
+	}
+	h /= 60;			// sector 0 to 5
+	i = floor( h );
+	f = h - i;			// factorial part of h
+	p = v * ( 1 - s );
+	q = v * ( 1 - s * f );
+	t = v * ( 1 - s * ( 1 - f ) );
+	switch( i ) {
+		case 0:
+			*r = v;
+			*g = t;
+			*b = p;
+			break;
+		case 1:
+			*r = q;
+			*g = v;
+			*b = p;
+			break;
+		case 2:
+			*r = p;
+			*g = v;
+			*b = t;
+			break;
+		case 3:
+			*r = p;
+			*g = q;
+			*b = v;
+			break;
+		case 4:
+			*r = t;
+			*g = p;
+			*b = v;
+			break;
+		default:		// case 5:
+			*r = v;
+			*g = p;
+			*b = q;
+			break;
+	}
+}
+
 }
 
 }