Diff: Colors.cpp

Revision:

0:a8535703f23b

Child:

3:2b5b03a3c0a5

diff -r 000000000000 -r a8535703f23b Colors.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Colors.cpp	Sat Jan 04 00:40:08 2014 +0000
@@ -0,0 +1,90 @@
+#include <math.h>
+#include <mbed.h>
+#include "Colors.h"
+
+void HSBtoRGB(float hue, float saturation, float brightness, uint8_t *pr, uint8_t *pg, uint8_t *pb)
+{
+    uint8_t r = 0, g = 0, b = 0;
+    if (saturation == 0) {
+        r = g = b = (uint8_t) (brightness * 255.0f + 0.5f);
+    } else {
+        float h = (hue - (float)floor(hue)) * 6.0f;
+        float f = h - (float)floor(h);
+        float p = brightness * (1.0f - saturation);
+        float q = brightness * (1.0f - saturation * f);
+        float t = brightness * (1.0f - (saturation * (1.0f - f)));
+        switch ((int) h) {
+            case 0:
+                r = (int) (brightness * 255.0f + 0.5f);
+                g = (int) (t * 255.0f + 0.5f);
+                b = (int) (p * 255.0f + 0.5f);
+                break;
+            case 1:
+                r = (int) (q * 255.0f + 0.5f);
+                g = (int) (brightness * 255.0f + 0.5f);
+                b = (int) (p * 255.0f + 0.5f);
+                break;
+            case 2:
+                r = (int) (p * 255.0f + 0.5f);
+                g = (int) (brightness * 255.0f + 0.5f);
+                b = (int) (t * 255.0f + 0.5f);
+                break;
+            case 3:
+                r = (int) (p * 255.0f + 0.5f);
+                g = (int) (q * 255.0f + 0.5f);
+                b = (int) (brightness * 255.0f + 0.5f);
+                break;
+            case 4:
+                r = (int) (t * 255.0f + 0.5f);
+                g = (int) (p * 255.0f + 0.5f);
+                b = (int) (brightness * 255.0f + 0.5f);
+                break;
+            case 5:
+                r = (int) (brightness * 255.0f + 0.5f);
+                g = (int) (p * 255.0f + 0.5f);
+                b = (int) (q * 255.0f + 0.5f);
+                break;
+        }
+    }
+    *pr = r;
+    *pg = g;
+    *pb = b;
+}
+
+float* RGBtoHSB(uint8_t r, uint8_t g, uint8_t b, float* hsbvals)
+{
+    float hue, saturation, brightness;
+    if (!hsbvals) {
+        hsbvals = new float[3];
+    }
+    uint8_t cmax = (r > g) ? r : g;
+    if (b > cmax) cmax = b;
+    uint8_t cmin = (r < g) ? r : g;
+    if (b < cmin) cmin = b;
+
+    brightness = ((float) cmax) / 255.0f;
+    if (cmax != 0)
+        saturation = ((float) (cmax - cmin)) / ((float) cmax);
+    else
+        saturation = 0;
+    if (saturation == 0)
+        hue = 0;
+    else {
+        float redc = ((float) (cmax - r)) / ((float) (cmax - cmin));
+        float greenc = ((float) (cmax - g)) / ((float) (cmax - cmin));
+        float bluec = ((float) (cmax - b)) / ((float) (cmax - cmin));
+        if (r == cmax)
+            hue = bluec - greenc;
+        else if (g == cmax)
+            hue = 2.0f + redc - bluec;
+        else
+            hue = 4.0f + greenc - redc;
+        hue = hue / 6.0f;
+        if (hue < 0)
+            hue = hue + 1.0f;
+    }
+    hsbvals[0] = hue;
+    hsbvals[1] = saturation;
+    hsbvals[2] = brightness;
+    return hsbvals;
+}