puff.cpp

《BATTLE OF SKY》

#include "puff.h"
#include <cassert>

using namespace std ;

// construct Puff
Puff::Puff(SimpleWindow &w):GameWindow(w) , CurrentDirection(Up) , PuffPhoto(4) {
	PuffPhoto.reserve(4);

    vector<string> BitMapFiles(4) ;
	BitMapFiles[0] = "bmp\\Puff-u.BMP" ;
	BitMapFiles[1] = "bmp\\Puff-r.BMP" ;
	BitMapFiles[2] = "bmp\\Puff-d.BMP" ;
	BitMapFiles[3] = "bmp\\Puff-l.BMP" ;

	for (Direction d = Up; d <= Left;
	 d = (Direction) (d + 1)) {
		GetBmp(d).SetWindow(GetWindow());
		GetBmp(d).Load(BitMapFiles[d]);
		assert(GetBmp(d).GetStatus() == BitMapOkay);
	} 
    SetPosition(Position(6.0 ,6.0)) ;

    // set the distance to move the enemy in the horizontal
	// or vertical directions. The distance is based
    // on the size of the bitmap.
    SetHorizMovement(GetBmp(GetDirection()).GetWidth() / 10.0) ; 
	SetVertMovement(GetBmp(GetDirection()).GetHeight() / 10.0) ;
}

//mutators
void Puff::Draw() {
	GetBmp(GetDirection()).Draw() ;
}

void Puff::Erase() {
	GetBmp(GetDirection()).Erase() ;
}

void Puff::SetPosition(const Position &p) {
	CurrentPosition = p ;
	for (Direction d = Up; d <= Left;
	 d = (Direction) (d + 1))
		PuffPhoto[d].SetPosition(p);
}

void Puff::SetDirection(const Direction &d) {
	CurrentDirection = d ;
}

void Puff::SetHorizMovement(float h) {
	HorizMovement = h ;
}

void Puff::SetVertMovement(float v) {
	VertMovement = v ;
}


//inspectors
Position Puff::GetPosition() const {
	return CurrentPosition ;
}

Direction Puff::GetDirection() const {
	return CurrentDirection ;
}

float Puff::GetHorizMovement() const {
	return HorizMovement ;
}

float Puff::GetVertMovement() const {
	return VertMovement ;
}

BitMap& Puff::GetBmp(const Direction &d) {
	return PuffPhoto[d] ;
}

const BitMap&  Puff::GetBmp(const Direction &d) const {
	return PuffPhoto[d] ;
}

SimpleWindow& Puff::GetWindow() const {
	return GameWindow ;
}

// check if enemy is at right edge of window
bool Puff::AtRightEdge() const {
	return (GetBmp(GetDirection()).GetPosition().GetXDistance() 
		+ GetBmp(GetDirection()).GetWidth() 
		+ HorizMovement >= 15.5) ;
}

// check if enemy is at left edge of window
bool Puff::AtLeftEdge() const {
    return (GetBmp(GetDirection()).GetPosition().GetXDistance() - HorizMovement <= 0.6 ) ;
}

// check if enemy is at bottom edge of window
bool Puff::AtBottomEdge() const {
	return (GetBmp(GetDirection()).GetPosition().GetYDistance() 
		+ GetBmp(GetDirection()).GetHeight() 
		+ VertMovement >= 15.5) ;
}

// check if enemy is at top edge of window
bool Puff::AtTopEdge() const {
	return (GetBmp(GetDirection()).GetPosition().GetYDistance() - VertMovement <= 0.6) ;
}


// compute a new position for a Puff
Position Puff::NewPosition() const {
    const Position OldPosition = GetPosition();
	if (GetDirection() == Left)
		return OldPosition
		 + Position(-GetHorizMovement(), 0);
	else if (GetDirection() == Right)
		return OldPosition
		 + Position(GetHorizMovement(), 0);
	else if (GetDirection() == Up)
		 return OldPosition
		 + Position(0, -GetVertMovement());
	else if(GetDirection() == Down)
		return OldPosition
		 + Position(0, GetVertMovement());
}

// the Puff move to direction 
void Puff::Move() {
	Direction d = GetDirection() ;
    
	switch(d) {
	case Up:
		if(AtTopEdge()) {
            Draw() ;
			break ;
		}
		else {
            Erase();
            SetPosition(NewPosition());
	        Draw();
			break ;
		}
	case Right:
		if(AtRightEdge()) {
			Draw() ;
			break ;
		}
		else {
            Erase() ;
            SetPosition(NewPosition());
	        Draw();
			break ;
		}
	case Down:
		if(AtBottomEdge()) {
			Draw() ;
			break ;
		}
		else { 
			Erase() ;
		    SetPosition(NewPosition());
	        Draw();
			break ;
		}
	case Left:
        if(AtLeftEdge()) {
			Draw() ;
			break ;
		}
		else { 
			Erase() ;
		    SetPosition(NewPosition());
	        Draw();
			break ;
		}
	}
	
}