<DIV
id=dot0 style="LEFT: 0px; VISIBILITY: hidden; WIDTH: 20px; POSITION:
absolute; TOP: 0px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <DIV id=dot1 style="LEFT: 0px; WIDTH: 20px; POSITION:
absolute; TOP: 29px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <DIV id=dot2 style="LEFT: 0px; WIDTH: 20px; POSITION:
absolute; TOP: 57px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <DIV id=dot3 style="LEFT: 0px; WIDTH: 20px; POSITION:
absolute; TOP: 75px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <DIV id=dot4 style="LEFT: 0px; WIDTH: 20px; POSITION:
absolute; TOP: 95px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <DIV id=dot5 style="LEFT: 0px; WIDTH: 20px; POSITION:
absolute; TOP: 97px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <DIV id=dot6 style="LEFT: 0px; WIDTH: 20px; POSITION:
absolute; TOP: 97px; HEIGHT: 20px"><IMG height=20 src="http://traumne.uw.hu/web38.gif" width=20>
</DIV> <SCRIPT language=JavaScript> <!-- hide
code
/* Elastic Trail script (By Philip Winston @ pwinston@yahoo.com, URL: http://www.geocities.com/pwinston/) Script featured
on Dynamicdrive.com For this and 100's more DHTML scripts, visit http://dynamicdrive.com */
var nDots =
7;
var Xpos =
0; var Ypos = 0;
//
fixed time step, no relation to real time var DELTAT = .01; // size
of one spring in pixels var SEGLEN = 10; // spring constant,
stiffness of springs var SPRINGK = 10; // all the physics is bogus,
just picked stuff to // make it look okay var MASS = 1; //
Positive XGRAVITY pulls right, negative pulls left // Positive YGRAVITY pulls
down, negative up var XGRAVITY = 0; var YGRAVITY = 50; // RESISTANCE
determines a slowing force proportional to velocity var RESISTANCE =
10; // stopping criterea to prevent endless jittering //
doesn't work when sitting on bottom since floor // doesn't push back
so acceleration always as big // as gravity var STOPVEL =
0.1; var STOPACC = 0.1; var DOTSIZE = 11; // BOUNCE is percent
of velocity retained when // bouncing off a wall var BOUNCE =
0.75;
var
isNetscape = navigator.appName=="Netscape";
//
always on for now, could be played with to // let dots fall to botton,
get thrown, etc. var followmouse = true;
var dots =
new Array(); init();
function
init() { var i = 0; for (i = 0; i
< nDots; i++) { dots[i] = new
dot(i); } if
(!isNetscape) { // I only know how
to read the locations of the //
<LI> items in IE //skip this
for now //
setInitPositions(dots) }
// set their positions for (i = 0;
i < nDots; i++) {
dots[i].obj.left = dots[i].X;
dots[i].obj.top = dots[i].Y; }
if (isNetscape)
{ // start right away since they
are positioned // at 0,
0
startanimate(); } else
{ // let dots sit there for a few
seconds // since they're hiding on
the real bullets
setTimeout("startanimate()", 1000); } }
function
dot(i) { this.X = Xpos; this.Y =
Ypos; this.dx = 0; this.dy =
0; if (isNetscape) {
this.obj = eval("document.dot" +
i); } else {
this.obj = eval("dot" + i + ".style"); } } function
startanimate() { setInterval("animate()",
20); }
// This
is to line up the bullets with actual LI tags on the page // Had to add
-DOTSIZE to X and 2*DOTSIZE to Y for IE 5, not sure why // Still doesn't work
great function setInitPositions(dots) { //
initialize dot positions to be on top // of the bullets
in the <ul> var startloc =
document.all.tags("LI"); var i = 0;
for (i = 0; i < startloc.length && i < (nDots - 1); i++)
{ dots[i+1].X =
startloc[i].offsetLeft
startloc[i].offsetParent.offsetLeft -
DOTSIZE; dots[i+1].Y =
startloc[i].offsetTop
+
startloc[i].offsetParent.offsetTop + 2*DOTSIZE;
} // put 0th dot above 1st (it is
hidden) dots[0].X = dots[1].X;
dots[0].Y = dots[1].Y - SEGLEN; }
// just
save mouse position for animate() to use function
MoveHandler(e) { Xpos = e.pageX;
Ypos = e.pageY; return true; }
// just
save mouse position for animate() to use function MoveHandlerIE()
{ Xpos = window.event.x +
document.body.scrollLeft; Ypos = window.event.y +
document.body.scrollTop; }
if
(isNetscape) {
document.captureEvents(Event.MOUSEMOVE);
document.onMouseMove = MoveHandler; } else {
document.onmousemove = MoveHandlerIE; }
function vec(X, Y) { this.X =
X; this.Y = Y; }
// adds
force in X and Y to spring for dot[i] on dot[j] function springForce(i, j,
spring) { var dx = (dots[i].X -
dots[j].X); var dy = (dots[i].Y -
dots[j].Y); var len = Math.sqrt(dx*dx +
dy*dy); if (len > SEGLEN)
{ var springF = SPRINGK * (len -
SEGLEN); spring.X += (dx / len) *
springF; spring.Y += (dy / len) *
springF; } }
function animate() { // dots[0] follows the
mouse, // though no dot is drawn
there var start = 0; if
(followmouse) { dots[0].X =
Xpos; dots[0].Y = Ypos;
start = 1;
} for (i = start ; i < nDots;
i++ ) {
var spring = new vec(0,
0); if (i > 0)
{
springForce(i-1, i, spring);
} if (i < (nDots - 1))
{
springForce(i+1, i, spring);
}
// air
resisitance/friction var resist =
new vec(-dots[i].dx *
RESISTANCE,
-dots[i].dy * RESISTANCE);
// compute new accel, including
gravity var accel = new
vec((spring.X + resist.X)/MASS +
XGRAVITY,
(spring.Y + resist.Y)/ MASS +
YGRAVITY);
// compute new
velocity dots[i].dx += (DELTAT *
accel.X); dots[i].dy += (DELTAT *
accel.Y);
// stop dead so it doesn't jitter
when nearly still if
(Math.abs(dots[i].dx) < STOPVEL
&&
Math.abs(dots[i].dy) < STOPVEL
&&
Math.abs(accel.X) < STOPACC
&&
Math.abs(accel.Y) < STOPACC)
{
dots[i].dx =
0;
dots[i].dy = 0;
}
// move to new
position dots[i].X +=
dots[i].dx; dots[i].Y +=
dots[i].dy;
// get size of
window var height,
width; if (isNetscape)
{ height =
window.innerHeight +
window.pageYOffset;
width = window.innerWidth +
window.pageXOffset; } else {
height =
document.body.clientHeight +
document.body.scrollTop;
width = document.body.clientWidth +
document.body.scrollLeft;
}
// bounce off 3 walls (leave
ceiling open) if (dots[i].Y
>= height - DOTSIZE - 1)
{ if
(dots[i].dy > 0)
{
dots[i].dy = BOUNCE *
-dots[i].dy;
}
dots[i].Y = height - DOTSIZE - 1;
} if (dots[i].X >= width -
DOTSIZE) {
if (dots[i].dx > 0)
{
dots[i].dx = BOUNCE *
-dots[i].dx;
}
dots[i].X = width - DOTSIZE - 1;
} if (dots[i].X < 0)
{ if
(dots[i].dx < 0)
{
dots[i].dx = BOUNCE *
-dots[i].dx;
}
dots[i].X = 0;
}
// move img to new
position dots[i].obj.left =
dots[i].X;
dots[i].obj.top = dots[i].Y;
} }
// end code
hiding --> </SCRIPT>
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