GameProg 26/11/12

#include <GL/glut.h>
#include <stdlib.h>
#include <math.h>
#include <iostream>
#include <fstream>
using namespace std;

double dt=0.01; // this is the time step
float verysmall=0.001;
float totaltime=0.0;
float gravity = 1.0;
GLfloat near=0.1,far=27.0;
GLfloat startdisp=-1;

class ball
{
	private:
		// ax acceleration in x, px position in x, vx velocity in x
		double ax,ay,az,px,py,pz,pxstart,pystart,pzstart,vx,vy,vz,cr,cg,cb,size,speed,anglexz,angleyz,initialspeed;

	private:
		bool ontee;

	public:
		ball(double pxIn, double pyIn, double pzIn, double crIn, double cgIn, double cbIn, double initialspeedIn, double angxzIn)
		{
			ontee = true;
			pxstart = pxIn;    px = pxIn;    vx = 0;    cr = crIn;    size = 0.1;     initialspeed = initialspeedIn;
			pystart = pyIn;    py = pyIn;    vy = 0;    cg = cgIn;    speed = 0;      anglexz = angxzIn;
			pzstart = pzIn;    pz = pzIn;    vz = 0;    cb = cbIn;    ay = gravity;   angleyz = 0;
		}

		double getpx(){return px;}	    double getvx(){return vx;};    double getcr(){return cr;}
		double getpy(){return py;};    double getvy(){return vy;};    double getcg(){return cg;}
		double getpz(){return pz;};    double getvz(){return vz;};    double getcb(){return cb;}

		double getspeed(){return  sqrt(py*py+px*px+pz*pz);}
		double getballsize(){return size;};

		double setpx(double pxIn){px = pxIn;}
		double setpy(double pyIn){py = pyIn;}
		double setpz(double pzIn){pz = pzIn;}


		void move()
		{
			if(ontee==false){return;}
			ontee=false;
			// convert information into vx vy and vz
			double pi=3.14;
			initialspeed;
			vy = initialspeed*sin((2*pi*angleyz)/360);
			vz = initialspeed*cos((2*pi*angleyz/360))*cos((2*pi*anglexz/360));
			vx = initialspeed*cos((2*pi*angleyz/360))*sin((2*pi*anglexz/360));
  		}


		void alterspeed(double xx)
		{
			if(ontee==false)
				return;

			initialspeed += xx;

			if(initialspeed < 0)
				initialspeed=0;
		}

		void rotateinxzplane(double xx)
		{
			if(ontee==false)
				return;
			anglexz += xx;
		}
    	void rotateinyzplane(double xx)
		{
			if(ontee==false)
				return;
			angleyz += xx;
		}

	    void info()
		{
		    if(ontee==false)return;
		    cout << "speed=" << initialspeed  << " anglexz=" << anglexz << " angleyz=" << angleyz << "\n";
		    double vya = initialspeed*sin(angleyz);
		    double vxa = initialspeed*cos(angleyz)*cos(anglexz);
		    double vza = initialspeed*cos(angleyz)*sin(anglexz);
		    cout << "corresponds to " << "vx="  << vxa  << " vy=" <<  vya << " vz=" << vza << "\n";
		    cout << "corresponds to " << "px="  << px  << " py=" <<  py << " pz=" << pz << "\n";
		    cout << "----------------------------------\n";
    	}

    	void reset()
		{
		    ontee=true;
		    px=pxstart;	 py=pystart;	pz=pzstart;	size=0.1;
		    vx=0;	vy=0;	vz=0;	ay=gravity;
		    //anglexz=180;
			angleyz=0;
	    }

    	void evolve()
		{
    		if(ontee==true)
			{
				return;
			}

    		//   cout << "vy" << vy << "\n";
    		vy += (-gravity*dt);
    		px += vx*dt;    py += vy*dt;   pz += vz*dt;
    		totaltime+=dt;
    		if(py < -0.0005)
    		{
				// bounce
				vy=-0.5*vy; py=0.0001;
    		}
			if(pz < 0.0)
    		{
				cout << "The ball has passed the origin\n";
				reset();
    		}
  		}
};

ball blackball ( 0, 0,  0, 0, 0.0, 0,  7, 0.0);
ball orangeball( 1, 0, 23, 1, 0.5, 0,  5, 180+2.49);
ball blueball  ( 3, 0, 23, 0, 0.0, 1,  2, 180+7.43);
ball greenball (-3, 0, 23, 0, 0.1, 0,  3, 180-7.43);
ball redball   (-1, 0, 23, 1, 0.0, 0,  4, 180-2.49);


void keyboard(unsigned char key, int x, int y)
{
   switch (key)
	{
	case 'd':  // rotate right
	  	  blackball.rotateinxzplane(5.0);break;
	case 'a':  // rotate left
	  blackball.rotateinxzplane(-5.0);break;
	case 'w':  // rotate up
	    blackball.rotateinyzplane(5.0);break;
	case 's':  // rotate down
	  blackball.rotateinyzplane(-5.0);break;
	case 'f':  //fire
	  blackball.move();
		break;
	case 'r':  // reset
	  blackball.reset(); break;
	case 'o':
	  blackball.alterspeed(0.5); break;
	case 'p':
	  blackball.alterspeed(-0.1); break;
	case 'i':
	  blackball.info(); break;
	   break;
		case 'q':exit(0);
    }

   glutPostRedisplay();
}

void init(void)
{
	glClearColor(1.0,1.0,1.0,0.0);

	glClearDepth(1.0);
	glEnable(GL_DEPTH_TEST);
	glDepthMask(GL_TRUE);
}

void display(void)
{
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(40,1,near,far);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
    gluLookAt(0.0, 2.0, 3.0,
			  0.0, 0.0, -10.0,
			  0.0, 1.0, 0.0);

	glClear(GL_COLOR_BUFFER_BIT);

	glPushMatrix();
		glColor3f (blackball.getcr(), blackball.getcg(), blackball.getcb());
		glTranslatef(blackball.getpx(),blackball.getpy(),blackball.getpz());
		glutSolidSphere(blackball.getballsize(),20,20);
	glPopMatrix();

	glPushMatrix();
		glColor3f (orangeball.getcr(), orangeball.getcg(), orangeball.getcb());
		glTranslatef(orangeball.getpx(),orangeball.getpy(),startdisp-orangeball.getpz());
		glutSolidSphere(orangeball.getballsize(),20,20);
	glPopMatrix();

	glPushMatrix();
		glColor3f (blueball.getcr(), blueball.getcg(), blueball.getcb());
		glTranslatef(blueball.getpx(),blueball.getpy(),startdisp-blueball.getpz());
		glutSolidSphere(blueball.getballsize(),20,20);
	glPopMatrix();

	glPushMatrix();
		glColor3f (greenball.getcr(), greenball.getcg(), greenball.getcb());
		glTranslatef(greenball.getpx(), greenball.getpy(),startdisp-greenball.getpz());
		glutSolidSphere(greenball.getballsize(),20,20);
	glPopMatrix();

	glPushMatrix();
		glColor3f (redball.getcr(), redball.getcg(), redball.getcb());
		glTranslatef(redball.getpx(), redball.getpy(),startdisp-redball.getpz());
		glutSolidSphere(redball.getballsize(),20,20);
	glPopMatrix();

	glFlush();
	glutSwapBuffers();
}

void evolve(int a)
{
	orangeball.move();
	blueball.move();
    greenball.move();
    redball.move();

	blackball.evolve();
	orangeball.evolve();
	blueball.evolve();
	greenball.evolve();
	redball.evolve();

	glutPostRedisplay();
	glutTimerFunc(20,evolve,20);
}

int main(int argc, char** argv)
{
	glutInit(&argc, argv);
    glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);
    glutInitWindowSize (800, 800);
    glutCreateWindow (argv[0]);
	init();
    glutKeyboardFunc (keyboard);
    //glutIdleFunc(evolve);
    glutTimerFunc(100,evolve,100);
    glutDisplayFunc (display);
    cout << "Hello All on CG6301\n";
    cout << "This program models projectile motion, the user picks the direction and  speed of the blackball\n";
    cout << "Note the following \n";
    cout << "`a' rotates left , `d' rotates right\n";
    cout << "`w' rotates up, `x' rotates down\n";
    cout << "`o' increases speed of shot, `p' decreases speed of shot\n";
    cout << "`i' info \n";
    cout << "`r' reset \n";

   glutMainLoop();
   return 0;
}