More cleaning up, seperating modules etc

1 files changed, 90 insertions, 0 deletions

diff --git a/Smoke/colormap.c b/Smoke/colormap.c
index 6cacb1b..ffb9afe 100644
--- a/Smoke/colormap.c
+++ b/Smoke/colormap.c
@@ -3,6 +3,8 @@
 #include <windows.h>
 #endif
 
+#include <math.h>
+
 #include "palette.h"
 #include "colormap.h"
 #include "funcs.h"
@@ -120,6 +122,94 @@ static float clamp(float value)
   return value;
 }
 
+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;
+	}
+
+}
+
+// r,g,b values are from 0 to 1
+// h = [0,360], s = [0,1], v = [0,1]
+//		if s == 0, then h = -1 (undefined)
+void RGBtoHSV( float r, float g, float b, float *h, float *s, float *v )
+{
+  float min, max, delta;
+
+	min = MIN3(r, g, b);
+	max = MAX3(r, g, b);
+	*v = max;				// v
+
+	delta = max - min;
+
+	if(max != 0) {
+		*s = delta / max;		// s
+  }	else {
+		// r = g = b = 0		// s = 0, v is undefined
+		*s = 0;
+		*h = -1;
+		return;
+	}
+
+	if(r == max) {
+		*h = ( g - b ) / delta;		// between yellow & magenta
+  }	else if(g == max) {
+		*h = 2 + (b - r) / delta;	// between cyan & yellow
+  } else {
+		*h = 4 + (r - g) / delta;	// between magenta & cyan
+  }
+	*h *= 60;				// degrees
+	if(*h < 0) {
+		*h += 360;
+  }
+}
+
 struct color4f colormap_get_color(float value)
 {
   struct color4f return_value;