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<div id='title'>
<h1>GSAP Bezier Curve Viewer</h1>
<h3>Bezier curves in GSAP are hard to visualize - this should make things easier.</h3>
<p>Notes
<ul>
<li>"Thru" curves use the objects starting position as the first control point and go through successive points. They also have an additional "curviness" setting. </li>
<li>"Soft" curves use the objects starting position as the first control point and have two control points per anchor point.</li>
<li>"Quadratic" curves have one control point per anchor point (plus one starting point) </li>
<li>"Cubic" curves have two control points per anchor point (plus one starting point)</li>
</ul>
</p>
</div>
<div id='container'>
<div id='content'>
<div id='build-curve'>
Select the curve type <select id='type'>
<option value="thru">Thru (default)</option>
<option value="soft">Soft</option>
<option value="quadratic">Quadratic</option>
<option value="cubic">Cubic</option>
</select><br>
<button id="add-curve">Add a curve</button>
<button id="rem-curve" style="display: none;">Remove a curve</button>
</div>
<div id='controls'>
Speed <input type="text" size="3em" id="speed" value="5"/><br>
Time Resolution <input type="text" size="3em" id="timeResolution" value="6"/><br>
<div class="hide-thru">Curviness <input type="text" size="3em" id="curviness" value="5" /><br></div>
Properties
<select id='properties'>
<option value="leftTop">Left, Top</option>
<option value="xy">X, Y</option>
</select><br>
Start Paused<input type="checkbox" id="paused" checked/>
Repeat<input type="checkbox" id="repeat"/><br>
Yoyo<input type="checkbox" id="yoyo"/>
AutoRotate<input type="checkbox" id="autoRotate"/><br>
<button id='playBtn'>Play</button>
</div>
</div>
</div>
<div id="show-curve"></div>
<div id="show-points"></div>
<div id='goose'></div>
<div id='code-container'>
<h3>Generated Code (ES6)</h3>
<pre id='code'></pre>
</div>
body{
font-family: 'Roboto', sans-serif;
margin: 0;
top: 0;
left: 0;
background-color: black;
}
h1{
font-weight: 900;
color: darkgrey;
}
h2,h3{
font-weight: 700;
color: darkgrey;
text-align: center;
}
p{
color: darkgrey;
text-align: center;
}
li{
text-align: left;
color: darkgrey;
}
.point-text{
font-weight: 200;
}
#title{
position: absolute;
top: 3%;
left: 5%;
width: 90%;
height: auto;
background-color: black;
text-align: center;
}
#container{
position: absolute;
top: 20%;
left: 3%;
width: 94%;
height: auto;
min-height: 77%;
background-color: black;
border: solid #7F7F7F 1px;
border-radius: 4px;
background-color: Transparent;
}
#code-container{
position: absolute;
top: 100%;
left: 3%;
width: 94%;
height: auto;
min-height: 77%;
margin-bottom: 3%;
background-color: black;
border: solid #7F7F7F 1px;
border-radius: 4px;
background-color: Transparent;
}
#content{
position: relative;
top: 0;
left: 0;
width: inherit;
height: inherit;
}
#build-curve{
background-color: Transparent;
position: absolute;
height: auto;
left: 2%;
top: 2%;
width: 45%;
color: #7F7F7F;
}
#controls{
position: absolute;
margin-top: 2%;
margin-right: 0;
right: 2%;
width: 45%;
color: #7F7F7F;
text-align: right;
}
input, option, select, button{
background-color: Transparent;
background-repeat: no-repeat;
cursor:pointer;
overflow: hidden;
outline:none;
color: #7F7F7F;
border: solid #7F7F7F 1px;
border-radius: 2px;
}
#code{
background-color: Transparent;
position: absolute;
left: 2%;
top: 100px;
height: auto;
width: 90%;
color: #7F7F7F;
}
button:hover {
background-image: linear-gradient(to bottom, #252525, #000000);
}
#playBtn{
width: 70%;
height: 50%;
line-height: 1.5;
font-weight: 700;
}
#goose{
position: absolute;
left: 85%;
top: 45%;
height: 15%;
width: 15%;
background: url(https://dl.dropbox.com/s/4075h5fbiw4bjll/goose.png) 0px 0% / contain no-repeat;
}
( () => {
"use strict";
let config = {
playing: false,
paused: true,
repeat: 0,
yoyo: false,
autoRotate: false,
animSpeed: 5,
type: 'thru',
timeResolution: 6,
ease: Linear.easeNone,
properties: "leftTop",
curviness: 5,
curves: 1,
//force3d: true,
};
let windowWidth = () => $(window).outerWidth(true);
let windowHeight = () => $(window).outerHeight(true);
const WW = windowWidth();
const WH = windowHeight();
//Return a window height % as a pixel value
let yPercentToPx = (y) => windowHeight() / 100 * y;
//Return a window width % as a pixel value
let xPercentToPx = (x) => windowHeight() / 100 * x;
let setElementSizes = (goose) => {
let $container = $('#container');
let spacing = 30;
let titleHeight = $('#title').height();
$container.css({top: (titleHeight + spacing) + "px" })
$container.css({height: ($("#build-curve").height() + spacing) + "px" })
$('#content').css({ height: $container.height() +"px" });
$("#code").css({ bottom: "2%" });
$("#code-container").css({top: titleHeight + spacing + $container.height() + spacing +"px"})
goose.left = windowWidth() - parseFloat($("#controls").css("width"))/2;
goose.top = titleHeight + 150 + $("#controls").height();
$("#goose").css({
left: goose.left,
top: goose.top,
})
}
// ***********************************************************************************
// *
// * This function allows us to visualize TweenMAx Bezier curves by drawing a
// * series of points along the curve
// *
// ***********************************************************************************
let visualizeTweenMaxBezier = (tween, steps) => {
//remove any existing curve
$("#show-curve").empty();
for (let i = 0; i < steps-1; i++){
tween.progress(i/steps);
$("#show-curve").append("<div id='point" + i + "'></div>");
$("#point"+i).css({
position: "absolute",
width: "2px",
height: "2px",
"background-color": "#7F7F7F",
top: tween.target.css("top"),
left: tween.target.css("left"),
});
}
tween.restart();
}
//Document ready
$(() => {
// ***********************************************************************************
// *
// * Lets create a timeline to animate the goose
// *
// *
// ***********************************************************************************
let $goose = $('goose');
let goose = {
elem: '#goose',
left: 0,
top: 0,
}
setElementSizes( goose );
//Draggable.create(goose.elem, {
// onRelease: reset,
//});
let pointDist = WW/10;
let values = [goose.left - pointDist];
let d = 1;
for( let i = 1; i < 8 ; i++){
if( i%2 === 0 ){
values[i] = values[i-2] - pointDist;
}
else{
values[i] = goose.top + (pointDist * d)/2;
d *= -1;
}
}
let quadValues = values.slice(0,6);
let createBezier = ( values ) => {
let curve = [];
//create an array of objects with either x,y or left, top attributes
for(let i=0; i < values.length; i += 2 ){
if( config.properties === "leftTop"){
curve.push({
left: values[i],
top: values[i+1],
});
}
else{
curve.push({
x: values[i],
y: values[i+1],
});
}
}
return curve;
}
let bezier = createBezier( values );
let buildTimeline = () => {
let timeline = new TimelineMax({
paused: config.paused,
repeat: config.repeat,
yoyo: config.yoyo,
onStart: () => {
$('#playBtn').html('Pause');
config.playing = true;
},
onComplete: () => {
$('#playBtn').html('Reset');
config.playing = false;
}
});
let move = TweenMax.to(goose.elem, config.animSpeed, {
bezier:{
type: config.type,
timeResolution : config.timeResolution,
values: bezier,
autoRotate: config.autoRotate,
},
ease: config.ease,
});
timeline.add(move, 0);
visualizeTweenMaxBezier(move, 200);
return timeline;
}
goose.timeline = buildTimeline();
// ***********************************************************************************
// *
// * Lets do it all again but put it to the screen so that it can be copied
// *
// *
// ***********************************************************************************
let displayCode = () => {
let code = "";
let timeline = "let timeline = new TimelineMax({ \n"
timeline +=" paused: " + config.paused + ", \n"
timeline +=" repeat: " + config.repeat + ", \n"
timeline +=" yoyo: " + config.yoyo + ","
timeline +=" \n});"
code += timeline;
let curve = "\n\nlet curve =";
curve += "[\n";
//create an array of objects with either x,y or left, top attributes
for(let i=0; i < values.length; i += 2 ){
if( config.properties === "leftTop"){
curve += " {\n";
curve +=" left: " + values[i] +",\n";
curve +=" top: " + values[i+1] +",\n";
curve += " },\n"
}
else{
curve += " {\n";
curve +=" x: " + values[i] +",\n";
curve +=" y: " + values[i+1] +",\n";
curve += " },\n"
}
}
curve += "]\n";
code += curve;
let tween = "\nlet tween = TweenMax.to(goose.elem, config.animSpeed, {\n";
tween +=" bezier:{\n";
tween +=" type: " + config.type + ",\n";
tween +=" curviness: " + config.curviness + ",\n";
tween +=" timeResolution: " + config.timeResolution + ",\n";
tween +=" values: curve,\n";
tween +=" autoRotate: " + config.autoRotate +",\n";
tween +=" },\n"
tween +=" ease: Linear.easeNone,\n";;
tween +="});\n";
code += tween;
code += "\ntimeline.add(tween, 0);";
//count how many lines of code we have so that the textarea can be resized
let lines = code.split(/[\n\r]/g).length + config.curves;
let lineHeight = "15";
$("#code").css({
'line-height': lineHeight + "px",
height: (lines*lineHeight) + "px",
});
$('#code').html(code);
$("#code-container").css({
height: (lines*lineHeight + 100) + "px",
});
}
displayCode();
// ***********************************************************************************
// *
// * Reset everything after options/points have changed
// *
// *
// ***********************************************************************************
let reset = () => {
setElementSizes( goose );
TweenMax.killAll();
if( config.type === "soft" || config.type === "quadratic" ){
bezier = createBezier( quadValues );
}
else{
bezier = createBezier( values );
}
goose.timeline = buildTimeline();
displayCode();
showPoints();
}
// ***********************************************************************************
// *
// * Draw the control points on the screen
// *
// *
// ***********************************************************************************
let showPoints = () => {
function onDrag(i) {
return function(e) {
let $target = $('#' + this.target.attributes[0].nodeValue );
if( config.type === "soft" || config.type === "quadratic" ){
quadValues[i*2] = parseFloat( $target.css('left') );
quadValues[(i*2)+1] = parseFloat( $target.css('top') );
}
else{
values[i*2] = parseFloat( $target.css('left') );
values[(i*2)+1] = parseFloat( $target.css('top') );
}
}
};
//get rid of any existing points
$("#show-points").empty();
let i = 0;
for(let point of bezier){
$("#show-points").append("<div id='control-point" + i + "'></div>");
$("#control-point"+i).css({
position: "absolute",
width: "8px",
height: "8px",
"background-color": "#5422A7",
"border-radius": "40px",
border: "solid #7F7F7F 1px",
top: point[Object.keys(point)[1]] + "px",
left: (point[Object.keys(point)[0]] - 3 )+ "px",
});
Draggable.create("#control-point"+i, {
type: "top,left",
onDrag: onDrag(i),
onRelease: reset,
});
i++;
}
}
showPoints();
// ***********************************************************************************
// *
// * Set up the play/pause/reset button
// *
// *
// ***********************************************************************************
$('#playBtn').click( ( ) => {
if($('#playBtn').html() === 'Reset'){
goose.timeline.restart();
goose.timeline.play();
$('#playBtn').html('Pause')
}
if($('#playBtn').html() === 'Play'){
goose.timeline.play();
$('#playBtn').html('Pause')
}
else{
$('#playBtn').html('Play')
goose.timeline.pause();
}
});
// ***********************************************************************************
// *
// * Set up options for the timeline
// *
// *
// ***********************************************************************************
//Whether animation should be paused at the start
$('#paused').click( ( ) => {
config.paused = $("#paused").is(":checked") ? true : false;
reset();
});
//repeat infinitely or once
$('#repeat').click( ( ) => {
config.repeat = $("#repeat").is(":checked") ? -1 : 0;
reset();
});
$('#yoyo').click( ( ) => {
config.yoyo = $("#yoyo").is(":checked") ? true : false;
reset();
});
//autoRotate or not, with 180 degrees added to stop the goose being upside down
$('#autoRotate').click( ( ) => {
config.autoRotate = $("#autoRotate").is(":checked") ? 180 : false;
TweenMax.killAll();
TweenMax.to(goose.elem, 0, { rotationZ: 0, ease:Quad.easeInOut });
goose.timeline = buildTimeline();
});
//overall animation speed across all curves
$("#speed").keyup(function(e){
if ( this.value === "" ) { //don't run if no text has been entered
return false;
};
if( isNaN(this.value) || this.value < 0 ){
this.value = this.defaultValue;
}
config.animSpeed = this.value;
reset();
});
//set the time resolution
$("#timeResolution").keyup(function(e){
if ( this.value === "" ) { //don't run if no text has been entered
return false;
};
if( isNaN(this.value) || this.value < 0 ){
this.value = this.defaultValue;
}
config.timeResolution = this.value;
reset();
});
//thru, soft, quadratic, or cubic
//hides the curviness option for all but soft
//and second control points for quadratic
$('#type').change( () => {
config.type = $('#type').val();
reset();
});
//animate via left and top or x and y
$('#properties').change( () => {
config.properties = $('#properties').val();
reset();
});
//curviness value for thru type curves
$("#curviness").keyup(function(e){
if ( this.value === "" ) { //don't run if no text has been entered
return false;
};
if( isNaN(this.value) || this.value < 0 ){
this.value = this.defaultValue;
}
config.curviness = this.value;
reset();
});
//add a curve and resize elements if we have lots of curves
$("#add-curve").click( () => {
config.curves ++;
let num = config.curves + 1;
let len = values.length;
for(let i = 0; i < 6; i++){
if(i%2 === 0){
values.push(values[ values.length - 2 ] - 50 );
}
else{
values.push(values[ i ] );
}
}
for(let i = 0; i < 4; i++){
if(i%2 === 0){
quadValues.push(values[ values.length - 2 ] - 50 );
}
else{
quadValues.push(values[ i ] );
}
}
$("#rem-curve").show();
reset();
});
//remove the last added curve and resize elements if neccessary
$("#rem-curve").click( () => {
config.curves --;
if(config.curves < 2 ){
$("#rem-curve").hide();
}
for(let i = 0; i < 6; i++){
values.pop();
}
for(let i = 0; i < 4; i++){
quadValues.pop();
}
reset();
});
//Detect changes to any of the points and update the curve
$("#points :text").change( function(e){
if ( this.value === "" ) { //don't run if no text has been entered
return false;
};
reset();
})
$(window).resize(_.debounce( () => {
setElementSizes( goose );
reset();
}, 300));
}); //end document ready
})();
Also see: Tab Triggers