BOUNCING BALL
Code Explanation
var nballx = ballx + ballvx;
var nbally = bally +ballvy;
if (nballx > boxboundx) {
ballvx =-ballvx;
nballx = boxboundx;
}
if (nballx < inboxboundx) {
nballx = inboxboundx
ballvx = -ballvx;
}
if (nbally > boxboundy) {
nbally = boxboundy;
ballvy =-ballvy;
}
if (nbally < inboxboundy) {
nbally = inboxboundy;
ballvy = -ballvy;
}
ballx = nballx;
bally = nbally;