Solving issue 1427: "HSV equalizer: wrong color lines"

rtengine/improcfun.cc

@@ -961,6 +961,11 @@ fclose(f);*/
 		}
 	}
 	
+	//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+	//
+	// WARNING: rtengine/color.cc have similar functions. I guess that color.cc was mistakenly committed from the denoise branch
+	//          in changeset #2493dd00b9f3. Code cleanup about those methods will have to be made when the denoise branch will be merged
+	//
 	//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 	
 	void ImProcFunctions::hsv2rgb (float h, float s, float v, float &r, float &g, float &b) {
@@ -987,6 +992,26 @@ fclose(f);*/
 		b = ((b1)*65535.0);
 	}
 	
+	// Function copied for speed concerns
+	// Not exactly the same as above ; this one return a result in the [0.0 ; 1.0] range
+	void ImProcFunctions::hsv2rgb01 (float h, float s, float v, float &r, float &g, float &b) {
+
+		float h1 = h*6; // sector 0 to 5
+		int i = int(h1);
+		float f = h1 - i; // fractional part of h
+
+		float p = v * ( 1 - s );
+		float q = v * ( 1 - s * f );
+		float t = v * ( 1 - s * ( 1 - f ) );
+
+		if      (i==1)    {r = q;  g = v;  b = p;}
+		else if (i==2)    {r = p;  g = v;  b = t;}
+		else if (i==3)    {r = p;  g = q;  b = v;}
+		else if (i==4)    {r = t;  g = p;  b = v;}
+		else if (i==5)    {r = v;  g = p;  b = q;}
+		else /*(i==0|6)*/ {r = v;  g = t;  b = p;}
+	}
+
 	void ImProcFunctions::xyz2srgb (float x, float y, float z, float &r, float &g, float &b) {
 		
 		//Transform to output color.  Standard sRGB is D65, but internal representation is D50

rtengine/improcfun.h

@@ -169,6 +169,7 @@ class ImProcFunctions {
 
 		static void rgb2hsv (float r, float g, float b, float &h, float &s, float &v);
 		static void hsv2rgb (float h, float s, float v, float &r, float &g, float &b);
+		static void hsv2rgb01 (float h, float s, float v, float &r, float &g, float &b);
 		void xyz2srgb (float x, float y, float z, float &r, float &g, float &b);
 		void xyz2rgb (float x, float y, float z, float &r, float &g, float &b, double rgb_xyz[3][3]);
 		void Lab2XYZ(float L, float a, float b, float &x, float &y, float &z);

rtgui/hsvequalizer.cc

@@ -190,27 +190,27 @@ void HSVEqualizer::colorForValue (double valX, double valY) {
 
 	if (ce == hshape) {        // Hue = f(Hue)
 
-		float h = (float)((valY - 0.5) * 2. + valX);
+		float h = float((valY - 0.5) * 2. + valX);
-		if (h > 1.0)
+		if (h > 1.0f)
-			h -= 1.0;
+			h -= 1.0f;
-		else if (h < 0.0)
+		else if (h < 0.0f)
-			h += 1.0;
+			h += 1.0f;
-		ImProcFunctions::hsv2rgb(h, (float)0.5, (float)0.5, r, g, b);
+		ImProcFunctions::hsv2rgb01(h, 0.5f, 0.5f, r, g, b);
-		red = (double)r;
+		red = double(r);
-		green = (double)g;
+		green = double(g);
-		blue = (double)b;
+		blue = double(b);
 	}
 	else if (ce == sshape) {   // Saturation = f(Hue)
-		ImProcFunctions::hsv2rgb((float)valX, (float)valY, (float)0.5, r, g, b);
+		ImProcFunctions::hsv2rgb01(float(valX), float(valY), 0.5f, r, g, b);
-		red = (double)r;
+		red = double(r);
-		green = (double)g;
+		green = double(g);
-		blue = (double)b;
+		blue = double(b);
 	}
 	else if (ce == vshape) {   // Value = f(Hue)
-		ImProcFunctions::hsv2rgb((float)valX, (float)0.5, (float)valY, r, g, b);
+		ImProcFunctions::hsv2rgb01(float(valX), 0.5f, float(valY), r, g, b);
-		red = (double)r;
+		red = double(r);
-		green = (double)g;
+		green = double(g);
-		blue = (double)b;
+		blue = double(b);
 	}
 	else {
 		printf("Error: no curve displayed!\n");