PocketEmpires/Camera.cpp

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

#include "Camera.h"
#include "Cursor.h"
#include <stdint.h>
#include <stdbool.h>

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

/*****************************************************************//**
 *
 * \brief   This macro defines camera speed, in pixels per frame.
 *
 *********************************************************************/
#define CAMERA_SPEED    (static_cast<int8_t>(4))

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

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

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

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

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

/*****************************************************************//**
 *
 * \brief   Constructor for Camera class.
 *
 *********************************************************************/
Camera::Camera(void) :
    _bLocked(false),
    _xOffset(0),
    _yOffset(0),
    _speedTimer(0)
{
}

uint16_t Camera::getRealX(const int16_t x) const
{
    return static_cast<uint16_t>(x + _xOffset);
}

uint16_t Camera::getRealY(const int16_t y) const
{
    return static_cast<uint16_t>(y + _yOffset);
}

/*****************************************************************//**
 *
 * \brief   This function transforms X coordinates for a given
 *          object to camera coordinates.
 *
 *********************************************************************/
int16_t Camera::getX(const uint16_t x) const
{
    return static_cast<int16_t>(x - _xOffset);
}

/*****************************************************************//**
 *
 * \brief   This function transforms Y coordinates for a given
 *          object to camera coordinates.
 *
 *********************************************************************/
int16_t Camera::getY(const uint16_t y) const
{
    return static_cast<int16_t>(y - _yOffset);
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          left arrow button.
 *
 *********************************************************************/
void Camera::onLeftBtnPressed(Cursor& cursor)
{
    if (not cursor.isXCentered())
    {
        /* Move cursor to initial position. */
        cursor.move(-CAMERA_SPEED);
    }
    else if (_xOffset >= CAMERA_SPEED)
    {
        /* Move camera to the left. */
        _xOffset -= CAMERA_SPEED;
    }
    else
    {
        /* Left screen margin reached.
         * Cursor has to be moved. */
        cursor.move(-CAMERA_SPEED);
    }
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          right arrow button.
 *
 *********************************************************************/
void Camera::onRightBtnPressed(Cursor& cursor)
{
    if (not cursor.isXCentered())
    {
        /* Move cursor to initial position. */
        cursor.move(CAMERA_SPEED);
    }
    else if (_xOffset < 512)
    {
        /* Move camera to the right. */
        _xOffset += CAMERA_SPEED;
    }
    else
    {
        /* Right screen margin reached.
         * Cursor has to be moved. */
        cursor.move(CAMERA_SPEED);
    }
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          up arrow button.
 *
 *********************************************************************/
void Camera::onUpBtnPressed(Cursor& cursor)
{
    if (not cursor.isYCentered())
    {
        /* Move cursor to initial position. */
        cursor.move(0, -CAMERA_SPEED);
    }
    else if (_yOffset > 0)
    {
        /* Move camera to the right. */
        _yOffset -= CAMERA_SPEED;
    }
    else
    {
        /* Upper screen margin reached.
         * Cursor has to be moved. */
        cursor.move(0, -CAMERA_SPEED);
    }
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          down arrow button.
 *
 *********************************************************************/
void Camera::onDownBtnPressed(Cursor& cursor)
{
    if (not cursor.isYCentered())
    {
        /* Move cursor to initial position. */
        cursor.move(0, CAMERA_SPEED);
    }
    else if (_yOffset < 512)
    {
        /* Move camera to the right. */
        _yOffset += CAMERA_SPEED;
    }
    else
    {
        /* Lower screen margin reached.
         * Cursor has to be moved. */
        cursor.move(0, CAMERA_SPEED);
    }
}

/*****************************************************************//**
 *
 * \brief   As its name suggests, this function adjusts camera lock.
 *
 *          When camera is locked, it cannot be moved when pressing
 *          direction keys.
 *
 * \param   bLock
 *              True if camera must be locked, false otherwise.
 *
 *********************************************************************/
void Camera::adjustLock(const bool bLock)
{
    _bLocked = bLock;
}

/*****************************************************************//**
 *
 * \brief   Returns camera lock state.
 *
 * \return  Returns true if camera is locked, false otherwise.
 *
 *********************************************************************/
bool Camera::isLocked(void) const
{
    return _bLocked;
}