NeoPixelBus/src/internal/HsbColor.cpp

/*-------------------------------------------------------------------------
HsbColor 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 "Rgb48Color.h"
#include "HsbColor.h"

void HsbColor::_RgbToHsb(float r, float g, float b, HsbColor* color)
{
    float max = (r > g && r > b) ? r : (g > b) ? g : b;
    float min = (r < g&& r < b) ? r : (g < b) ? g : b;

    float d = max - min;

    float h = 0.0;
    float v = max;
    float s = (v == 0.0f) ? 0 : (d / v);

    if (d != 0.0f)
    {
        if (r == max)
        {
            h = (g - b) / d + (g < b ? 6.0f : 0.0f);
        }
        else if (g == max)
        {
            h = (b - r) / d + 2.0f;
        }
        else
        {
            h = (r - g) / d + 4.0f;
        }
        h /= 6.0f;
    }


    color->H = h;
    color->S = s;
    color->B = v;
}

HsbColor::HsbColor(const RgbColor& color)
{
    // convert colors to float between (0.0 - 1.0)
    float r = color.R / 255.0f;
    float g = color.G / 255.0f;
    float b = color.B / 255.0f;

    _RgbToHsb(r, g, b, this);
}

HsbColor::HsbColor(const Rgb48Color& color)
{
    // convert colors to float between (0.0 - 1.0)
    float r = color.R / 65535.0f;
    float g = color.G / 65535.0f;
    float b = color.B / 65535.0f;

    _RgbToHsb(r, g, b, this);
}