i need to reach this output but im having trouble with setting a random colour for each ball respectively, i had a bit of help from a cousin but he left and im having trouble understanding some of the codes because he is overseas
i have this code so far but i need to get this:
http://sleepeater.net/comp115assignment3HD/applet/
int bColor = 0; //background color
int screenWL = 600; //screen width and length
int numberB = int(random(5,21)); //number of balls
int alphaB = 200; //alpha value of the ball
float v_threshold_H = 6;
float v_threshold_L = 0.5;
Ball[] ball = new Ball[numberB];
void setup()
{
size(600,600);
background(bColor,bColor,bColor);
smooth();
noStroke();
//initialize balls
for(int i=0; i<numberB; i++)
{
int dia = int(random(30,200));
ball[i] = new Ball(random(0+dia,screenWL-dia),random(0+dia,screenWL-dia),dia,random(-5,5),random(-5,5),alphaB,int(random(80,255)),int(random(80,255)),int(random(80,255)));
}
//check if balls overlap
for(int i=0; i<numberB; i++)
{
for(int j=i; j<numberB; j++)
{
if(i!=j)
{
float distance = dist(ball[i].x,ball[i].y,ball[j].x,ball[j].y);
if(distance<=(ball[i].d+ball[j].d)/2+1)
{
ball[i].d = floor(distance/2);
ball[j].d = floor(distance/2);
}
}
}
}
}
void draw()
{
//clean screen
background(255);
//collision
for(int i=0; i<numberB; i++)
{
for(int j=i; j<numberB; j++)
{
if(i!=j)
{
float distance = dist(ball[i].x,ball[i].y,ball[j].x,ball[j].y);
if(distance<=(ball[i].d+ball[j].d)/2)
{
//start vector
PVector vi_s = new PVector(ball[i].vx, ball[i].vy);
PVector vj_s = new PVector(ball[j].vx, ball[j].vy);
//calculate the unit vector between two center points
PVector c1 = new PVector(ball[j].x-ball[i].x, ball[j].y-ball[i].y);
c1.normalize();
//calculate the perpendicular vector of c1
PVector c2 = new PVector(c1.y, -1*c1.x);
//calculate the final vector after collision projected on c1
//assume the mass is in proportion to the diameter
float coef_i1 = (ball[i].d-ball[j].d)/(ball[i].d+ball[j].d);
float coef_i2 = (2*ball[j].d)/(ball[i].d+ball[j].d);
float coef_j1 = (2*ball[i].d)/(ball[i].d+ball[j].d);
float coef_j2 = (ball[j].d-ball[i].d)/(ball[i].d+ball[j].d);
PVector vi_f_c1 = new PVector(coef_i1*vi_s.dot(c1)*c1.x+coef_i2*vj_s.dot(c1)*c1.x, coef_i1*vi_s.dot(c1)*c1.y+coef_i2*vj_s.dot(c1)*c1.y);
PVector vj_f_c1 = new PVector(coef_j1*vi_s.dot(c1)*c1.x+coef_j2*vj_s.dot(c1)*c1.x, coef_j1*vi_s.dot(c1)*c1.y+coef_j2*vj_s.dot(c1)*c1.y);
//calculate the final vector after collision projected on c2
PVector vi_f_c2 = new PVector(vi_s.dot(c2)*c1.x, vi_s.dot(c2)*c1.y);
PVector vj_f_c2 = new PVector(vj_s.dot(c2)*c1.x, vj_s.dot(c2)*c1.y);
//calculate the final vector after collision
PVector vi_f = new PVector(vi_f_c1.x+vi_f_c2.x, vi_f_c1.y+vi_f_c2.y);
PVector vj_f = new PVector(vj_f_c1.x+vj_f_c2.x, vj_f_c1.y+vj_f_c2.y);
//adjust velocity according to thresholds
if(vi_f.x>v_threshold_H) vi_f.x=v_threshold_H;
else if(vi_f.x<v_threshold_H*-1) vi_f.x=v_threshold_H*-1;
if(vi_f.y>v_threshold_H) vi_f.y=v_threshold_H;
else if(vi_f.y<v_threshold_H*-1) vi_f.y=v_threshold_H*-1;
if(vj_f.x>v_threshold_H) vj_f.x=v_threshold_H;
else if(vj_f.x<v_threshold_H*-1) vj_f.x=v_threshold_H*-1;
if(vj_f.y>v_threshold_H) vj_f.y=v_threshold_H;
else if(vj_f.y<v_threshold_H*-1) vj_f.y=v_threshold_H*-1;
if(vi_f.x<v_threshold_L && vi_f.x>0) vi_f.x=v_threshold_L;
else if(vi_f.x>v_threshold_L*-1 && vi_f.x<0) vi_f.x=v_threshold_L*-1;
if(vi_f.y<v_threshold_L && vi_f.y>0) vi_f.y=v_threshold_L;
else if(vi_f.y>v_threshold_L*-1 && vi_f.y<0) vi_f.y=v_threshold_L*-1;
if(vj_f.x<v_threshold_L && vj_f.x>0) vj_f.x=v_threshold_L;
else if(vj_f.x>v_threshold_L*-1 && vj_f.x<0) vj_f.x=v_threshold_L*-1;
if(vj_f.y<v_threshold_L && vj_f.y>0) vj_f.y=v_threshold_L;
else if(vj_f.y>v_threshold_L*-1 && vj_f.y<0) vj_f.y=v_threshold_L*-1;
//update the velocity
ball[i].vx = vi_f.x;
ball[i].vy = vi_f.y;
ball[j].vx = vj_f.x;
ball[j].vy = vj_f.y;
//pull out the balls to avoid overlaping
float pullMag = abs(distance-(ball[i].d+ball[j].d)/2);
ball[i].x -= pullMag*c1.x;
ball[i].y -= pullMag*c1.y;
ball[j].x += pullMag*c1.y;
ball[j].y += pullMag*c1.y;
}
}
}
}
//balls
for(int i=0; i<numberB; i++)
{
//reset
//reach boundary
float nextX = ball[i].x+(ball[i].vx/abs(ball[i].vx))*ball[i].d/2;
float nextY = ball[i].y+(ball[i].vy/abs(ball[i].vy))*ball[i].d/2;
if(nextX>=screenWL || nextX<=0) ball[i].vx *= -1;
if(nextY>=screenWL || nextY<=0) ball[i].vy *= -1;
//update
ball[i].x += ball[i].vx;
ball[i].y += ball[i].vy;
//render
fill(ball[i].r,ball[i].g,ball[i].b,ball[i].a);
ellipse(ball[i].x,ball[i].y,ball[i].d,ball[i].d);
}
}
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