V2

src/RgbColor.cpp

@@ -0,0 +1,215 @@
+/*-------------------------------------------------------------------------
+RgbColor provides a color object that can be directly consumed by NeoPixelBus
+
+Written by Michael C. Miller.
+
+I invest time and resources providing this open source code,
+please support me by dontating (see https://github.com/Makuna/NeoPixelBus)
+
+-------------------------------------------------------------------------
+This file is part of the Makuna/NeoPixelBus library.
+
+NeoPixelBus is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as
+published by the Free Software Foundation, either version 3 of
+the License, or (at your option) any later version.
+
+NeoPixelBus is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with NeoPixel.  If not, see
+<http://www.gnu.org/licenses/>.
+-------------------------------------------------------------------------*/
+
+#include "RgbColor.h"
+#include "HslColor.h"
+#include "HsbColor.h"
+
+static float _CalcColor(float p, float q, float t)
+{
+    if (t < 0.0f)
+        t += 1.0f;
+    if (t > 1.0f)
+        t -= 1.0f;
+
+    if (t < 1.0f / 6.0f)
+        return p + (q - p) * 6.0f * t;
+
+    if (t < 0.5f)
+        return q;
+
+    if (t < 2.0f / 3.0f)
+        return p + ((q - p) * (2.0f / 3.0f - t) * 6.0f);
+
+    return p;
+}
+
+RgbColor::RgbColor(HslColor color)
+{
+    float r;
+    float g;
+    float b;
+
+    float h = color.H;
+    float s = color.S;
+    float l = color.L;
+
+
+    if (color.S == 0.0f || color.L == 0.0f)
+    {
+        r = g = b = l; // achromatic or black
+    }
+    else 
+    {
+        float q = l < 0.5f ? l * (1.0f + s) : l + s - (l * s);
+        float p = 2.0f * l - q;
+        r = _CalcColor(p, q, h + 1.0f / 3.0f);
+        g = _CalcColor(p, q, h);
+        b = _CalcColor(p, q, h - 1.0f / 3.0f);
+    }
+
+    R = (uint8_t)(r * 255.0f);
+    G = (uint8_t)(g * 255.0f);
+    B = (uint8_t)(b * 255.0f);
+}
+
+RgbColor::RgbColor(HsbColor color)
+{
+    float r;
+    float g;
+    float b;
+
+    float h = color.H;
+    float s = color.S;
+    float v = color.B;
+
+    if (color.S == 0.0f)
+    {
+        r = g = b = v; // achromatic or black
+    }
+    else
+    {
+        if (h < 0.0f)
+            h += 1.0f;
+        if (h > 1.0f)
+            h -= 1.0f;
+        h *= 6.0f;
+        int i = (int)h;
+        float f = h - i;
+        float q = v * (1.0f - s * f);
+        float p = v * (1.0f - s);
+        float t = v * (1.0f - s * (1.0f - 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:
+            r = v;
+            g = p;
+            b = q;
+            break;
+        }
+    }
+
+    R = (uint8_t)(r * 255.0f);
+    G = (uint8_t)(g * 255.0f);
+    B = (uint8_t)(b * 255.0f);
+}
+
+uint8_t RgbColor::CalculateBrightness() const
+{
+	return (uint8_t)(((uint16_t)R + (uint16_t)G + (uint16_t)B) / 3);
+}
+
+void RgbColor::Darken(uint8_t delta)
+{
+	if (R > delta)
+	{
+		R -= delta;
+	}
+	else
+	{
+		R = 0;
+	}
+
+	if (G > delta)
+	{
+		G -= delta;
+	}
+	else
+	{
+		G = 0;
+	}
+
+	if (B > delta)
+	{
+		B -= delta;
+	}
+	else
+	{
+		B = 0;
+	}
+}
+
+void RgbColor::Lighten(uint8_t delta)
+{
+	if (R < 255 - delta)
+	{
+		R += delta;
+	}
+	else
+	{
+		R = 255;
+	}
+
+	if (G < 255 - delta)
+	{
+		G += delta;
+	}
+	else
+	{
+		G = 255;
+	}
+
+	if (B < 255 - delta)
+	{
+		B += delta;
+	}
+	else
+	{
+		B = 255;
+	}
+}
+
+RgbColor RgbColor::LinearBlend(RgbColor left, RgbColor right, float progress)
+{
+	return RgbColor( left.R + ((right.R - left.R) * progress),
+		left.G + ((right.G - left.G) * progress),
+		left.B + ((right.B - left.B) * progress));
+}