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#ifndef __INC_HSV2RGB_H
#define __INC_HSV2RGB_H
#include "FastLED.h"
#include "pixeltypes.h"
FASTLED_NAMESPACE_BEGIN
// hsv2rgb_rainbow - convert a hue, saturation, and value to RGB
// using a visually balanced rainbow (vs a straight
// mathematical spectrum).
// This 'rainbow' yields better yellow and orange
// than a straight 'spectrum'.
//
// NOTE: here hue is 0-255, not just 0-191
void hsv2rgb_rainbow( const struct CHSV& hsv, struct CRGB& rgb);
void hsv2rgb_rainbow( const struct CHSV* phsv, struct CRGB * prgb, int numLeds);
#define HUE_MAX_RAINBOW 255
// hsv2rgb_spectrum - convert a hue, saturation, and value to RGB
// using a mathematically straight spectrum (vs
// a visually balanced rainbow).
// This 'spectrum' will have more green & blue
// than a 'rainbow', and less yellow and orange.
//
// NOTE: here hue is 0-255, not just 0-191
void hsv2rgb_spectrum( const struct CHSV& hsv, struct CRGB& rgb);
void hsv2rgb_spectrum( const struct CHSV* phsv, struct CRGB * prgb, int numLeds);
#define HUE_MAX_SPECTRUM 255
// hsv2rgb_raw - convert hue, saturation, and value to RGB.
// This 'spectrum' conversion will be more green & blue
// than a real 'rainbow', and the hue is specified just
// in the range 0-191. Together, these result in a
// slightly faster conversion speed, at the expense of
// color balance.
//
// NOTE: Hue is 0-191 only!
// Saturation & value are 0-255 each.
//
void hsv2rgb_raw(const struct CHSV& hsv, struct CRGB & rgb);
void hsv2rgb_raw(const struct CHSV* phsv, struct CRGB * prgb, int numLeds);
#define HUE_MAX 191
// rgb2hsv_approximate - recover _approximate_ HSV values from RGB.
//
// NOTE 1: This function is a long-term work in process; expect
// results to change slightly over time as this function is
// refined and improved.
//
// NOTE 2: This function is most accurate when the input is an
// RGB color that came from a fully-saturated HSV color to start
// with. E.g. CHSV( hue, 255, 255) -> CRGB -> CHSV will give
// best results.
//
// NOTE 3: This function is not nearly as fast as HSV-to-RGB.
// It is provided for those situations when the need for this
// function cannot be avoided, or when extremely high performance
// is not needed.
//
// NOTE 4: Why is this 'only' an "approximation"?
// Not all RGB colors have HSV equivalents! For example, there
// is no HSV value that will ever convert to RGB(255,255,0) using
// the code provided in this library. So if you try to
// convert RGB(255,255,0) 'back' to HSV, you'll necessarily get
// only an approximation. Emphasis has been placed on getting
// the 'hue' as close as usefully possible, but even that's a bit
// of a challenge. The 8-bit HSV and 8-bit RGB color spaces
// are not a "bijection".
//
// Nevertheless, this function does a pretty good job, particularly
// at recovering the 'hue' from fully saturated RGB colors that
// originally came from HSV rainbow colors. So if you start
// with CHSV(hue_in,255,255), and convert that to RGB, and then
// convert it back to HSV using this function, the resulting output
// hue will either exactly the same, or very close (+/-1).
// The more desaturated the original RGB color is, the rougher the
// approximation, and the less accurate the results.
//
CHSV rgb2hsv_approximate( const CRGB& rgb);
FASTLED_NAMESPACE_END
#endif
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