gballoon.cpp

C++&datastructure书籍源码,以前外教提供现在与大家共享

#include "randgen.h"
#include "canvas.h"
#include "utils.h"
#include "gballoon.h"
#include <sstream>



static const int ALT_CHANGE = 10;
static const int JUMP_SIZE = 5;

static const int LEGEND_HEIGHT=15;
static const int RADIUS = 16;
static const int CABLE_HEIGHT = RADIUS/2;
static const int CABLE_WIDTH = 2;
static const int HEIGHT = 3*RADIUS;
static const int BASKET_SIZE = 8;

static const int CANVAS_HEIGHT=300;
static const int CANVAS_WIDTH =400;


AnimatedCanvas Balloon::ourCanvas(CANVAS_WIDTH,CANVAS_HEIGHT,10,10);
int Balloon::ourCount = 0;

Balloon::Balloon()
{
    Create(GOLD);
}

Balloon::Balloon(color c)
{
    Create(c);
}

void Balloon::Ascend(int height)
{
    cout << endl; Message();
    cout << " **** rising to " << height << " meters " << endl;
    
    while (myAltitude < height)
    {
        Message();
        Burn();
    }
}

void Balloon::Descend(int height)
{
    cout << endl; Message();
    cout << " **** descending to " << height << " meters " << endl;
    
    while (myAltitude > height)
    {
        Message();
        Vent();
    }
}

void Balloon::Message()
{
    cout << "balloon #" << myCount << " at (" << mySteps << ", " 
         << myAltitude << ")    \t";
}

void Balloon::Cruise(int steps)
{
    const int START = myAltitude;
    const int MARGIN = 5;
    
    cout << endl; Message();
    
    cout << " ***** Cruise at " << START << " m. for ";
    cout << steps << " secs." << endl;

    int k;
    for(k=0; k < steps; k++)
    {
        Message();
        mySteps += 1;
        AdjustAltitude();
        if (myAltitude > (START+MARGIN))
        {
            cout << " too high! ";
            Vent();
        }
        else if (myAltitude < (START-MARGIN))
        {
            cout << " too low! ";
            Burn();
        }
        else
        {
            Display();
        }
    }
}

int Balloon::GetLocation() const
{
    return mySteps;
}

int Balloon::GetAltitude() const
{
    return myAltitude;
}

void Balloon::AdjustAltitude()
{
    RandGen rand;
    
    if (rand.RandInt(0,1)==1)
    {
        int change = rand.RandInt(-JUMP_SIZE,JUMP_SIZE);
        
        myAltitude += change;
        if (change != 0)
        {
            cout << " wind-shear ";
            cout.setf(ios::showpos);
            cout << change << " ";
            cout.unsetf(ios::showpos);
        }
        
        if (myAltitude < 0)    // keep balloon above ground
        {
            myAltitude = 0;
        }
    }
}

void Balloon::Burn()
{
    myAltitude += ALT_CHANGE;
    cout << " burn ";
    Display();
}

void Balloon::Vent()
{
    myAltitude -= ALT_CHANGE;
    if (myAltitude < 0)
    {
        myAltitude = 0;
    }
    cout << " vent ";
    Display();
}

void Balloon::Display()
{
    myShape->moveTo(Point(RADIUS+mySteps,
                          CANVAS_HEIGHT - myDisplayHeight - myAltitude));
    ostringstream os;
    os << "# " << myCount << " at (" << mySteps << ", " << myAltitude << ")";
    myLegend->changeText(os.str());
    ourCanvas.repaint();
    
    cout << endl;
}

void Balloon::Create(color c)
{
    myAltitude = 0;
    mySteps = 0;
    myCount = ourCount;
    ourCount++;
    if (myCount == 0)
    {
        ourCanvas.SetTitle("Balloon Display");
    }
    
    CompositeShape *cs = new CompositeShape();
    cs->add(new CircleShape(Point(RADIUS,RADIUS),RADIUS,c));
    
    
    tvector<Point> trapezoid;
    trapezoid.push_back(Point(0,RADIUS));
    trapezoid.push_back(Point(2*RADIUS,RADIUS));
    trapezoid.push_back(Point(3*RADIUS/2,HEIGHT));
    trapezoid.push_back(Point(RADIUS/2,HEIGHT));
    PolygonShape * ps = new PolygonShape(trapezoid,trapezoid.size(),c);
    cs->add(ps);
    
    cs->add(new RectangleShape(Point(RADIUS-BASKET_SIZE/2,HEIGHT),
                               CABLE_WIDTH,CABLE_HEIGHT,c));
                               
    cs->add(new RectangleShape(Point(RADIUS+BASKET_SIZE/2-CABLE_WIDTH,HEIGHT),
                               CABLE_WIDTH,CABLE_HEIGHT,c));
    cs->add(new RectangleShape(Point(RADIUS-BASKET_SIZE/2,HEIGHT+CABLE_HEIGHT),
                               BASKET_SIZE,BASKET_SIZE,c));

    //cs->add(new RectangleShape(RADIUS,RADIUS/2,c,Point(RADIUS/2,HEIGHT)));
    //cs->add(new RectangleShape(2,HEIGHT,c,Point(RADIUS/2,RADIUS/2)));
    //cs->add(new RectangleShape(2,HEIGHT,c,Point(3*RADIUS/2-2,RADIUS/2)));
    
    // ImageShape *cs = new ImageShape(* new image("c:\\book\\ed2\\code\\balloon2.jpg"),Point(RADIUS,RADIUS));
    
    myShape = new Mover(*cs);
    myLegend = new TextShape(Point(0,myCount*LEGEND_HEIGHT),"            ",c);
    ourCanvas.addShape(myLegend);
    ourCanvas.addShape(myShape);
    myDisplayHeight = myShape->bbox().height();
    
    Display();   
}