five_bit_semantics.h

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#pragma once
 
// Per-chip 5-bit field semantics for the colour-managed HD path (P8, B1,
// #4042).
//
// APA102-class parts drive their 5-bit field as a secondary slow PWM stage,
// so a joint code/field solve may use it for low-light resolution, bounded
// below by a flicker floor. SK9822's field is a current gain whose effect on
// chromaticity is not characterised, so it is held fixed. A chip whose
// semantics are not known gets the SK9822-conservative treatment. A bound
// profile's `five_bit_semantics`, when it says anything, overrides the chip's
// default.
 
#include "fl/chipsets/spi_chipsets.h"
#include "fl/gfx/color_profile.h"  // FiveBitSemantics
#include "fl/stl/int.h"
#include "fl/stl/noexcept.h"
 
namespace fl {

FiveBitSemantics fiveBitSemanticsFor(SpiChipset chip,
                                     FiveBitSemantics profile) FL_NO_EXCEPT;

u8 hdMinimumField(FiveBitSemantics semantics, u8 floor_setting) FL_NO_EXCEPT;
 
namespace detail {
u8& hdFieldFloor() FL_NO_EXCEPT;
}  // namespace detail
 
}  // namespace fl