d=300;c.width=c.height=d;f=v=h=u=0;H="rgba(0,0,0,0.5)";I="#fff";R="red";K=document;function M(){return 2*(Math.floor(Math.random()*(d/2)))}x=M();y=M();w=W=7;X=Y=M();function C(){a.fillStyle=H;a.fillRect(0,0,d,d)}function P(I){a.fillStyle=I;a.fillText("score: "+Math.floor(f/10),8,10)}z=setInterval("m()",50);function m(){f++;if(f%100==0){u=10;W++}if(u>0){r=4;s=2;u--}else{r=2;s=4}if(Y<y)Y+=r;else Y-=r;if(X<x)X+=r;else X-=r;if(v=="u"&&y>8)y-=s;if(v=="d"&&y<d-8)y+=s;if(h=="l"&&x>8)x-=s;if(h=="r"&&x<d-8)x+=s;function E(){S=X-x;D=Y-y;F=w+W;return(S*S+D*D<=F*F)}if(E()){clearInterval(z);setInterval(function(){q(X,Y,R,W);W++;P("#000")},5)}C();function q(x,y,n,w){a.fillStyle=n;a.beginPath();a.arc(x,y,w,0,Math.PI*2,true);a.fill()}q(x,y,"#0FF",w);q(X,Y,R,W);P(I)}K.onkeydown=function(e){k=e.keyCode;if(k==37)h="l";if(k==38)v="u";if(k==39)h="r";if(k==40)v="d"};K.onkeyup=function(e){k=e.keyCode;if(k==37||k==39)h="";if(k==38||k==40)v=""}
d = 300; // dimensions
c.width = c.height = d;
f = v = h = u = 0; // f = score, h = horizontal direction, v = verticle direction, u = countdown
H = "rgba(0,0,0,0.5)";
I = "#fff";
R = "red";
K = document;
function M() {
return 2 * (Math.floor(Math.random() * (d / 2)))
}
x = M();
y = M();
w = W = 7; // disc widths
X = Y = M();
function C() {a.fillStyle = H; a.fillRect(0, 0, d, d)} // clear canvas
function P(I) { // score (colour)
a.fillStyle = I;
a.fillText("score: " + Math.floor(f/10), 8, 10)
}
z = setInterval("m()", 50);
function m() { // animation
f++;
if (f % 100 == 0) {u = 10; W++}
if (u > 0) {
r = 4; // chaser speed
s = 2; // your speed
u--
} else {
r = 2;
s = 4
}
// Chase
if (Y < y) Y += r; else Y -= r;
if (X < x) X += r; else X -= r;
//move user
if (v == "u" && y > 8) y -= s;
if (v == "d" && y < d - 8) y += s;
if (h == "l" && x > 8) x -= s;
if (h == "r" && x < d - 8) x += s;
function E() { // check collision
S = X - x;
D = Y - y;
F = w + W;
return (S * S + D * D <= F * F)
}
if (E()) {
clearInterval(z);
setInterval(function () {
q(X, Y, R, W);
W++;
P("#000")
}, 5);
}
// draw canvas
C(); // Clear canvas
function q(x, y, n, w) { // draw shapes: x,y = position, n = colour, w = width
a.fillStyle = n;
a.beginPath();
a.arc(x, y, w, 0, Math.PI * 2, true);
a.fill();
}
q(x, y, "#0FF", w);
q(X, Y, R, W);
P(I);
}
K.onkeydown = function (e) {
k = e.keyCode;
if (k == 37) h = "l";
if (k == 38) v = "u";
if (k == 39) h = "r";
if (k == 40) v = "d";
};
K.onkeyup = function (e) {
k = e.keyCode;
if (k == 37 || k == 39) h = "";
if (k == 38 || k == 40) v = ""
}
