PocketEmpires/Unit.cpp

/* *******************************************************************
 *  Includes
 * ******************************************************************/

#include "BaseUnit.h"
#include "Unit.h"
#include "Sprite.h"
#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>

/* *******************************************************************
 *  Defines
 * ******************************************************************/

/* *******************************************************************
 *  Types definition
 * ******************************************************************/

/* *******************************************************************
 *  Global variables definition
 * ******************************************************************/

/* *******************************************************************
 *  Local variables definition
 * ******************************************************************/

/*****************************************************************//**
 *
 * \brief   Bitmap data for idle UNIT_ID_PEASANT.
 *
 *********************************************************************/
static const PROGMEM uint8_t au8PeasantSprData[] =
{
    8,
    8,
    0x00,
    0x3C,
    0x42,
    0x99,
    0xA5,
    0x66,
    0x18,
    0x00
};

/* *******************************************************************
 *  Local prototypes declaration
 * ******************************************************************/

/* *******************************************************************
 *  Functions definition
 * ******************************************************************/

/*****************************************************************//**
 *
 * \brief   Constructor for Unit class.
 *
 *********************************************************************/
Unit::Unit(const enum Unit::tUnitID eUnitID) :
BaseUnit(),
_eUnitID(eUnitID),
_eState(UNIT_STATE_IDLE),
_target_x(0),
_target_y(0)
{
}

/*****************************************************************//**
 *
 * \brief   Creates a Unit instance by setting default parameters
 *          and X/Y coordinates.
 *
 *********************************************************************/
void Unit::create(const enum Unit::tUnitID eUnitID, const uint16_t x, const uint16_t y)
{
    /* Execute base class function first. */
    BaseUnit::create(x, y);

    /* Assign new ID to selected Unit. */
    _eUnitID = eUnitID;

    /* This table relates all available
     * unit IDs against a bitmap data table. */
    const uint8_t au8HpData[MAX_UNIT_ID] PROGMEM =
    {
        [UNIT_ID_NONE]      = 0,
        [UNIT_ID_PEASANT]   = 25,
        [UNIT_ID_SWORDMAN]  = 35
    };

    /* Assign health according to unit ID. */
    _hp = au8HpData[eUnitID];
}

/*****************************************************************//**
 *
 * \brief   This function sets a position target for a \ref Unit
 *          object.
 *
 *********************************************************************/
void Unit::moveTo(const uint16_t x, const uint16_t y)
{
    _target_x = x;
    _target_y = y;
    _eState = UNIT_STATE_MOVING;
}

/*****************************************************************//**
 *
 * \brief   Periodical handler for Unit class.
 *
 *********************************************************************/
void Unit::handler(void)
{
    /* Execute base class handler. */
    BaseUnit::handler();

    switch (_eState)
    {
        case UNIT_STATE_MOVING:
            if (_x < _target_x)
            {
                _x += 1;
            }
            else if (_x > _target_x)
            {
                _x -= 1;
            }

            if (_y < _target_y)
            {
                _y += 1;
            }
            else if (_y > _target_y)
            {
                _y -= 1;
            }
        break;

        case UNIT_STATE_IDLE:
        default:
        break;
    }
}

/*****************************************************************//**
 *
 * \brief   This function checks whether unit is inside screen
 *          boundaries and draws its associated bitmap.
 *
 *********************************************************************/
void Unit::drawHandler(void)
{
    if (_eUnitID < MAX_UNIT_ID)
    {
        /* This table relates all available
         * unit IDs against a bitmap data table. */
        const uint8_t* const apu8UnitSpriteDataTable[MAX_UNIT_ID] PROGMEM =
        {
            [UNIT_ID_NONE]      = NULL,
            [UNIT_ID_PEASANT]   = au8PeasantSprData,
            [UNIT_ID_SWORDMAN]  = NULL
        };

        /* Point to appropiate bitmap data given unit ID. */
        const uint8_t* const pu8UnitSpriteData = apu8UnitSpriteDataTable[_eUnitID];

        Sprite spr(pu8UnitSpriteData);

        spr.setPos(_x - (Sprite::getWidth(pu8UnitSpriteData) >> 1), _y - (Sprite::getHeight(pu8UnitSpriteData) >> 1));

        spr.draw();

        BaseUnit::drawHandler(pu8UnitSpriteData);
    }
    else
    {
        /* Unit has an invalid ID. Exit. */
    }
}