itgmania212121/src/arch/Lights/SextetUtils.h

#ifndef SextetUtils_H
#define SextetUtils_H

#include "LightsDriver.h"

/*
 * Utility functions that both `LightsDriver_Win32Serial` and `LightsDriver_SextetStream`
 * take advantage of, in order to encode the lights data into a common format.
 */

 // Number of printable characters used to encode lights
static const size_t CABINET_SEXTET_COUNT = 1;
static const size_t CONTROLLER_SEXTET_COUNT = 6;

// Number of bytes to contain the full pack and a trailing LF
static const size_t FULL_SEXTET_COUNT = CABINET_SEXTET_COUNT + (NUM_GameController * CONTROLLER_SEXTET_COUNT) + 1;

// Serialization routines

// Encodes the low 6 bits of a byte as a printable, non-space ASCII
// character (i.e., within the range 0x21-0x7E) such that the low 6 bits of
// the character are the same as the input.
inline uint8_t printableSextet(uint8_t data)
{
	// Maps the 6-bit value into the range 0x30-0x6F, wrapped in such a way
	// that the low 6 bits of the result are the same as the data (so
	// decoding is trivial).
	//
	//	00nnnn	->	0100nnnn (0x4n)
	//	01nnnn	->	0101nnnn (0x5n)
	//	10nnnn	->	0110nnnn (0x6n)
	//	11nnnn	->	0011nnnn (0x3n)

	// Put another way, the top 4 bits H of the output are determined from
	// the top two bits T of the input like so:
	// 	H = ((T + 1) mod 4) + 3

	return ((data + (uint8_t)0x10) & (uint8_t)0x3F) + (uint8_t)0x30;
}

// Packs 6 booleans into a 6-bit value
inline uint8_t packPlainSextet(bool b0, bool b1, bool b2, bool b3, bool b4, bool b5)
{
	return (uint8_t)(
		(b0 ? 0x01 : 0) |
		(b1 ? 0x02 : 0) |
		(b2 ? 0x04 : 0) |
		(b3 ? 0x08 : 0) |
		(b4 ? 0x10 : 0) |
		(b5 ? 0x20 : 0));
}

// Packs 6 booleans into a printable sextet
inline uint8_t packPrintableSextet(bool b0, bool b1, bool b2, bool b3, bool b4, bool b5)
{
	return printableSextet(packPlainSextet(b0, b1, b2, b3, b4, b5));
}

// Packs the cabinet lights into a printable sextet and adds it to a buffer
inline size_t packCabinetLights(const LightsState* ls, uint8_t* buffer)
{
	buffer[0] = packPrintableSextet(
		ls->m_bCabinetLights[LIGHT_MARQUEE_UP_LEFT],
		ls->m_bCabinetLights[LIGHT_MARQUEE_UP_RIGHT],
		ls->m_bCabinetLights[LIGHT_MARQUEE_LR_LEFT],
		ls->m_bCabinetLights[LIGHT_MARQUEE_LR_RIGHT],
		ls->m_bCabinetLights[LIGHT_BASS_LEFT],
		ls->m_bCabinetLights[LIGHT_BASS_RIGHT]);
	return CABINET_SEXTET_COUNT;
}

// Packs the button lights for a controller into 6 printable sextets and
// adds them to a buffer
inline size_t packControllerLights(const LightsState* ls, GameController gc, uint8_t* buffer)
{
	// Menu buttons
	buffer[0] = packPrintableSextet(
		ls->m_bGameButtonLights[gc][GAME_BUTTON_MENULEFT],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_MENURIGHT],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_MENUUP],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_MENUDOWN],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_START],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_SELECT]);

	// Other non-sensors
	buffer[1] = packPrintableSextet(
		ls->m_bGameButtonLights[gc][GAME_BUTTON_BACK],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_COIN],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_OPERATOR],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_EFFECT_UP],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_EFFECT_DOWN],
		false);

	// Sensors
	buffer[2] = packPrintableSextet(
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_01],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_02],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_03],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_04],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_05],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_06]);
	buffer[3] = packPrintableSextet(
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_07],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_08],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_09],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_10],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_11],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_12]);
	buffer[4] = packPrintableSextet(
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_13],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_14],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_15],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_16],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_17],
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_18]);
	buffer[5] = packPrintableSextet(
		ls->m_bGameButtonLights[gc][GAME_BUTTON_CUSTOM_19],
		false,
		false,
		false,
		false,
		false);

	return CONTROLLER_SEXTET_COUNT;
}

inline size_t packLine(uint8_t* buffer, const LightsState* ls)
{
	size_t index = 0;

	index += packCabinetLights(ls, &(buffer[index]));

	FOREACH_ENUM(GameController, gc)
	{
		index += packControllerLights(ls, gc, &(buffer[index]));
	}

	// Terminate with LF
	buffer[index++] = 0xA;

	return index;
}

#endif

/*
 * Copyright © 2014 Peter S. May
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to permit
 * persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
 * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 */