多视角3D可旋转的HTML5Logo动画示例代码详细介绍

<p class="link-overlay">

</p>
<canvas id="canvas" style="background-color:#ddd"></canvas>

// bind to window onload handler
window.addEventListener('load', onloadHandler, false);

/**
 * Window onload handler
 */
function onloadHandler()
{
 var canvas = document.getElementById('canvas');
 canvas.width = window.innerWidth;
 canvas.height = window.innerHeight;
 var k3dmain = new K3D.Controller(canvas, true);

 // generate 3D objects

 var obj1 = new K3D.K3DObject();
 with (obj1)
 {
 drawmode = "solid";
 shademode = "lightsource";
 sortmode = "unsorted";
 addphi = -0.5;
 abouty = -90;
 perslevel = 1000;
 init(
 [{x:-80,y:180,z:0},{x:0,y:180,z:-80},{x:0,y:0,z:-80},{x:-80,y:20,z:0},{x:-50,y:150,z:-30},{x:0,y:150,z:-80},{x:0,y:130,z:-80},{x:-30,y:130,z:-50},{x:-28,y:110,z:-52},{x:0,y:110,z:-80},{x:0,y:90,z:-80},{x:-45,y:90,z:-35},{x:-44,y:80,z:-36},{x:-25,y:80,z:-55},{x:-22,y:66,z:-58},{x:0,y:60,z:-80},{x:0,y:40,z:-80},{x:-40,y:50,z:-40}],
 [],
 [{color:[227,76,38],vertices:[0,1,2,3,0]},{color:[235,235,235],vertices:[4,5,6,7,8,9,10,11,4]},{color:[235,235,235],vertices:[12,13,14,15,16,17,12]}]
 );
 }
 k3dmain.addK3DObject(obj1);

 var obj2 = new K3D.K3DObject();
 with (obj2)
 {
 drawmode = "solid";
 shademode = "lightsource";
 sortmode = "unsorted";
 addphi = -0.5;
 abouty = -90;
 perslevel = 1000;
 init(
 [{x:0,y:180,z:-80},{x:80,y:180,z:0},{x:80,y:20,z:0},{x:0,y:0,z:-80},{x:0,y:165,z:-80},{x:68,y:165,z:-12},{x:55,y:35,z:-25},{x:0,y:20,z:-80},{x:0,y:150,z:-80},{x:50,y:150,z:-30},{x:47,y:130,z:-33},{x:0,y:130,z:-80},{x:0,y:110,z:-80},{x:45,y:110,z:-35},{x:40,y:50,z:-40},{x:0,y:40,z:-80},{x:0,y:60,z:-80},{x:20,y:66,z:-60},{x:23,y:90,z:-57},{x:0,y:90,z:-80}],
 [],
 [{color:[227,76,38],vertices:[0,1,2,3,0]},{color:[240,101,41],vertices:[4,5,6,7,4]},{color:[235,235,235],vertices:[8,9,10,11,8]},{color:[235,235,235],vertices:[12,13,14,15,16,17,18,19,12]}]
 );
 }
 k3dmain.addK3DObject(obj2);

 var obj3 = new K3D.K3DObject();
 with (obj3)
 {
 drawmode = "solid";
 shademode = "lightsource";
 sortmode = "unsorted";
 addphi = -0.5;
 abouty = -90;
 perslevel = 1000;
 init(
 [{x:80,y:180,z:0},{x:0,y:180,z:80},{x:0,y:0,z:80},{x:80,y:20,z:0},{x:50,y:150,z:30},{x:0,y:150,z:80},{x:0,y:130,z:80},{x:30,y:130,z:50},{x:28,y:110,z:52},{x:0,y:110,z:80},{x:0,y:90,z:80},{x:45,y:90,z:35},{x:44,y:80,z:36},{x:25,y:80,z:55},{x:22,y:66,z:58},{x:0,y:60,z:80},{x:0,y:40,z:80},{x:40,y:50,z:40}],
 [],
 [{color:[227,76,38],vertices:[0,1,2,3,0]},{color:[235,235,235],vertices:[4,5,6,7,8,9,10,11,4]},{color:[235,235,235],vertices:[12,13,14,15,16,17,12]}]
 );
 }
 k3dmain.addK3DObject(obj3);

 var obj4 = new K3D.K3DObject();
 with (obj4)
 {
 drawmode = "solid";
 shademode = "lightsource";
 sortmode = "unsorted";
 addphi = -0.5;
 abouty = -90;
 perslevel = 1000;
 init(
 [{x:0,y:180,z:80},{x:-80,y:180,z:0},{x:-80,y:20,z:0},{x:0,y:0,z:80},{x:0,y:165,z:80},{x:-68,y:165,z:12},{x:-55,y:35,z:25},{x:0,y:20,z:80},{x:0,y:150,z:80},{x:-50,y:150,z:30},{x:-47,y:130,z:33},{x:0,y:130,z:80},{x:0,y:110,z:80},{x:-45,y:110,z:35},{x:-40,y:50,z:40},{x:0,y:40,z:80},{x:0,y:60,z:80},{x:-20,y:66,z:60},{x:-23,y:90,z:57},{x:0,y:90,z:80}],
 [],
 [{color:[227,76,38],vertices:[0,1,2,3,0]},{color:[240,101,41],vertices:[4,5,6,7,4]},{color:[235,235,235],vertices:[8,9,10,11,8]},{color:[235,235,235],vertices:[12,13,14,15,16,17,18,19,12]}]
 );
 }
 k3dmain.addK3DObject(obj4);

 var objBase = new K3D.K3DObject();
 with (objBase)
 {
 drawmode = "solid";
 shademode = "lightsource";
 sortmode = "unsorted";
 addphi = -0.5;
 abouty = -90;
 perslevel = 1000;
 init(
 [{x:0,y:0,z:-80},{x:-80,y:20,z:0},{x:0,y:0,z:80},{x:80,y:20,z:0}],
 [],
 [{color:[227,76,38],vertices:[0,2,1,0]},{color:[227,76,38],vertices:[0,3,2,0]}]
 );
 }
 k3dmain.addK3DObject(objBase);

 var objHtml = new K3D.K3DObject();
 with (objHtml)
 {
 drawmode = "solid";
 shademode = "lightsource";
 //sortmode = "unsorted";
 color = [64,64,64];
 doublesided = true;
 addphi = -0.5;
 abouty = 100;
 scale = 0.75;
 perslevel = 1000;
 init(
 [{x:-80,y:40,z:0},{x:-70,y:40,z:0},{x:-70,y:30,z:0},{x:-60,y:30,z:0},{x:-60,y:40,z:0},{x:-50,y:40,z:0},{x:-50,y:10,z:0},{x:-60,y:10,z:0},{x:-60,y:20,z:0},{x:-70,y:20,z:0},{x:-70,y:10,z:0},{x:-80,y:10,z:0},{x:-40,y:40,z:0},{x:-10,y:40,z:0},{x:-10,y:30,z:0},{x:-20,y:30,z:0},{x:-20,y:10,z:0},{x:-30,y:10,z:0},{x:-30,y:30,z:0},{x:-40,y:30,z:0},{x:0,y:40,z:0},{x:10,y:40,z:0},{x:20,y:30,z:0},{x:30,y:40,z:0},{x:40,y:40,z:0},{x:40,y:10,z:0},{x:30,y:10,z:0},{x:30,y:30,z:0},{x:20,y:20,z:0},{x:10,y:30,z:0},{x:10,y:10,z:0},{x:0,y:10,z:0},{x:50,y:40,z:0},{x:60,y:40,z:0},{x:60,y:20,z:0},{x:80,y:20,z:0},{x:80,y:10,z:0},{x:50,y:10,z:0}],
 [],
 [{vertices:[0,1,2,3,4,5,6,7,8,9,10,11,0]},{vertices:[12,13,14,15,16,17,18,19,12]},{vertices:[20,21,22,23,24,25,26,27,28,29,30,31,20]},{vertices:[32,33,34,35,36,37,32]}]
 );
 }
 k3dmain.addK3DObject(objHtml);

 // add render loop callback
 var ctx = canvas.getContext('2d');
 var rotationOffset = 0;
 var len = (canvas.height > canvas.width ? canvas.height : canvas.width) * 0.7;
 k3dmain.clearBackground = false;
 k3dmain.callback = function()
 {
 // manually clear bg - as we want to render some extra goodies
 ctx.clearRect(0, 0, canvas.width, canvas.height);

 // draw bg effect before K3D does its 3D rendering
 ctx.save();
 ctx.translate(canvas.width/2, canvas.height/2);
 ctx.rotate(rotationOffset);

 // first fill pass - outer rays
 var RAYCOUNT = 24;
 ctx.fillStyle = "#eee";
 ctx.beginPath();
 for (var i=0; i<RAYCOUNT; i++)
 {
 // rotate context
 ctx.rotate(TWOPI / RAYCOUNT);
 ctx.moveTo(0, 0);
 ctx.lineTo(-20, len);
 ctx.lineTo(20, len);
 }
 ctx.closePath();
 ctx.fill();
 // second fill pass - inner rays
 ctx.fillStyle = "#fff";
 ctx.beginPath();
 for (var i=0; i<RAYCOUNT; i++)
 {
 // rotate context
 ctx.rotate(TWOPI / RAYCOUNT);
 ctx.moveTo(0, 0);
 ctx.lineTo(-15, len);
 ctx.lineTo(15, len);
 }
 ctx.closePath();
 ctx.fill();
 ctx.restore();
 rotationOffset += 0.005;

 // apply user interaction to rotation
 for (var i=0, objs=k3dmain.objects; i<objs.length; i++)
 {
 objs[i].ophi += targetRotationX;
 }

 if (targetRotationX > -0.5) targetRotationX -= 0.05;
 else if (targetRotationX < -0.55) targetRotationX += 0.05;
 if (targetRotationX > -0.55 && targetRotationX < -0.5) targetRotationX = -0.5;
 };

 // start demo loop
 k3dmain.paused = true;
 setInterval(function(){k3dmain.tick()}, 1000/60);
}

// nifty drag/touch event capture code borrowed from Mr Doob http://www.gxlcms.com/
var targetRotationX = 0;
var targetRotationOnMouseDownX = 0;
var mouseX = 0;
var mouseXOnMouseDown = 0;
var targetRotationY = 0;
var targetRotationOnMouseDownY = 0;
var mouseY = 0;
var mouseYOnMouseDown = 0;

var windowHalfX = window.innerWidth / 2;
var windowHalfY = window.innerHeight / 2;

document.addEventListener('mousedown', onDocumentMouseDown, false);
document.addEventListener('touchstart', onDocumentTouchStart, false);
document.addEventListener('touchmove', onDocumentTouchMove, false);

function onDocumentMouseDown( event ) {

	event.preventDefault();

	document.addEventListener('mousemove', onDocumentMouseMove, false);
	document.addEventListener('mouseup', onDocumentMouseUp, false);
	document.addEventListener('mouseout', onDocumentMouseOut, false);

	mouseXOnMouseDown = event.clientX - windowHalfX;
	targetRotationOnMouseDownX = targetRotationX;
	mouseYOnMouseDown = event.clientY - windowHalfY;
	targetRotationOnMouseDownY = targetRotationY;
}

function onDocumentMouseMove( event )
{
	mouseX = event.clientX - windowHalfX;
	targetRotationX = targetRotationOnMouseDownX + (mouseX - mouseXOnMouseDown) * 0.02;
	mouseY = event.clientY - windowHalfY;
	targetRotationY = targetRotationOnMouseDownY + (mouseY - mouseYOnMouseDown) * 0.02;
}

function onDocumentMouseUp( event )
{
	document.removeEventListener('mousemove', onDocumentMouseMove, false);
	document.removeEventListener('mouseup', onDocumentMouseUp, false);
	document.removeEventListener('mouseout', onDocumentMouseOut, false);
}

function onDocumentMouseOut( event )
{
	document.removeEventListener('mousemove', onDocumentMouseMove, false);
	document.removeEventListener('mouseup', onDocumentMouseUp, false);
	document.removeEventListener('mouseout', onDocumentMouseOut, false);
}

function onDocumentTouchStart( event )
{
	if (event.touches.length == 1)
	{
	event.preventDefault();

	mouseXOnMouseDown = event.touches[0].pageX - windowHalfX;
	targetRotationOnMouseDownX = targetRotationX;
	mouseYOnMouseDown = event.touches[0].pageY - windowHalfY;
	targetRotationOnMouseDownY = targetRotationY;
	}
}

function onDocumentTouchMove( event )
{
	if (event.touches.length == 1)
	{
	event.preventDefault();

	mouseX = event.touches[0].pageX - windowHalfX;
	targetRotationX = targetRotationOnMouseDownX + (mouseX - mouseXOnMouseDown) * 0.05;
	mouseY = event.touches[0].pageY - windowHalfY;
	targetRotationY = targetRotationOnMouseDownY + (mouseX - mouseYOnMouseDown) * 0.05;
	}
}