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<!doctype html>
<html lang="en.png">
<head>
<meta charset="utf-8">
<title>WebGL through Three JS</title>
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="apple-mobile-web-app-status-bar-style" content="black-translucent" />
<link href='http://fonts.googleapis.com/css?family=Lato:400,700,400italic,700italic' rel='stylesheet' type='text/css'>
<link rel="stylesheet" href="css/main.css">
<link rel="stylesheet" href="css/theme/default.css">
<link rel="stylesheet" href="css/custom.css">
<!-- For syntax highlighting -->
<link rel="stylesheet" href="lib/css/zenburn.css">
<script>
// If the query includes 'print-pdf' we'll use the PDF print sheet
document.write( '<link rel="stylesheet" href="css/print/' + ( window.location.search.match( /print-pdf/gi ) ? 'pdf' : 'paper' ) + '.css" type="text/css" media="print">' );
</script>
<!--[if lt IE 9]>
<script src="lib/js/html5shiv.js"></script>
<![endif]-->
</head>
<body>
<div class="reveal">
<!-- Used to fade in a background when a specific slide state is reached -->
<div class="state-background"></div>
<!-- Any section element inside of this container is displayed as a slide -->
<div class="slides">
<section>
<h1>WebGL with Three JS</h1>
<h3>Real time rendering with javascript</h3>
<canvas data-sample="spinning_wireframe_torus"></canvas>
</section>
<section>
<h2>Rendering Techniques</h2>
<ul>
<li>
Rasterization
<blockquote style="width:90%">
The task of taking an image described in a vector graphics format (shapes)
and converting it into a raster image (pixels or dots)
</blockquote>
</li>
<br/>
<br/>
<li>Ray Casting</li>
<li>Ray Tracing</li>
</ul>
</section>
<section>
<section>
<h3>How do we get from<br/>vertices to a shape</h3>
<img class="float_left" style="display:inline" src="images/Vertices.png">
<div class="float_left" style="line-height: 8; padding: 20px">to</div>
<canvas data-sample="spinning_wireframe_cube" class="float_left" style="display:inline"></canvas>
<div class="float_left" style="line-height: 5; padding: 20px">?</div>
</section>
<section>
<h2>What is a vertex?</h2>
<img class="white_bg" src="http://obviam.net/wp-content/uploads/2011/01/Vertices.png">
</section>
<section>
<h2>Model Space and World Space</h2>
<img src="http://robertokoci.com/images/posts/graphics/game/programming/matrix-unveiled/ObjectWorldSpace.png">
<!-- <img class="float_left" src="http://www.simulshop.com/product/nemethdesigns/ec135/tn_fsx2008-49-47.jpg" style="height: 70%"> -->
</section>
<section>
<h2>View Space</h2>
<img src="http://robertokoci.com/images/posts/graphics/game/programming/matrix-unveiled/WorldViewSpace.png">
</section>
<section>
<h2>Projection Space</h2>
<img src="http://robertokoci.com/images/posts/graphics/game/programming/matrix-unveiled/ProjectionMatrix.png">
</section>
<section>
<h2>End in 2D</h2>
<img src="images/3dproj01.gif">
<!-- <img class="white_bg" src="http://upload.wikimedia.org/wikipedia/commons/thumb/4/48/Axonometric_projection.svg/467px-Axonometric_projection.svg.png"> -->
</section>
<section>
<h2>Vertices to a shape</h2>
<img class="float_left" style="display:inline" src="images/Vertices.png">
<div class="float_left" style="line-height: 8; padding: 20px">to</div>
<canvas data-sample="spinning_wireframe_cube" class="float_left" style="display:inline"></canvas>
</section>
<section>
<h2>But how do we ...</h2>
<br/>
<h3>transform between spaces?</h3>
<img src="http://robertokoci.com/images/posts/graphics/game/programming/matrix-unveiled/ObjectWorldSpace.png">
<br/>
<blockquote style="width:100%">Model -> World -> View -> Projection Space</blockquote>
</section>
</section>
<section>
<section>
<h2>Welcome to Linear Algebra</h2>
<img src="http://storiesbywilliams.files.wordpress.com/2012/05/transport.jpg">
</section>
<section>
<h3>2D Vertex, meet Matrix!</h3>
<p>Now multiply...</p>
<img class="float_left" src="http://tutorial.math.lamar.edu/Classes/LinAlg/LinearTransformations_files/image002.gif">
<br/>
<ol>
<li><img class="white_bg" src="images/matrix_multiplication_x_axis_start.png"></li>
<li class="fragment">
<img class="white_bg" src="images/matrix_multiplication_x_axis_x.png">
( 1 * x ) + ( 0 * y ) = x
</li>
<li class="fragment">
<img class="white_bg" src="images/matrix_multiplication_x_axis_y.png">
( 0 * x ) + ( -1 * y ) = -y
</li>
</ol>
</section>
<section>
<h3>Transformations</h3>
<br/>
<img class="float_left" src="images/SRT_transformations.png">
<ul style="width:100px;">
<li>
identity:<br/>
<img class="white_bg" style="width: 200px" src="images/identity_matrix.png">
</li>
<li>
scaling:<br/>
<img class="white_bg" style="width: 200px" src="http://upload.wikimedia.org/math/2/6/a/26a088adf02ba09dc958acba0e81a3c3.png">
<br/>
</li>
<li>
rotation:<br/>
<img class="white_bg" style="width: 200px" src="http://upload.wikimedia.org/math/4/b/d/4bd8fd7253c5bbd65c2e9f8fb7220b19.png">
<br/>
</li>
</ul>
</section>
<section>
<h2>Projection</h2>
<br/>
<pre style="width: 40%" class="math float_left">
[1, 0, 0] [x] [x]
[0, 1, 0] [y] = [y]
[0, 0, 0] [z] [0] </pre>
<p>* We lose a dimension!</p>
<img src="images/3dproj01.gif">
</section>
<section>
<h2>Composite Transformation</h2>
<p>Putting it all together</p>
<img class="white_bg" src="http://upload.wikimedia.org/wikipedia/commons/thumb/4/48/Axonometric_projection.svg/467px-Axonometric_projection.svg.png">
<blockquote>World_View_Projection_Matrix =<br/> World * View * Projection</blockquote>
</section>
<section>
<h2>Transformations + Projection</h2>
<img class="float_left" style="display:inline" src="images/Vertices.png">
<div class="float_left" style="line-height: 8; padding: 20px">to</div>
<canvas data-sample="spinning_wireframe_cube" style="display:inline"></canvas>
<p class="medium" style="font-size:24px;">----------------------------------
<br/>
Model * World_View_Projection_Matrix</p>
</section>
</section>
<section>
<section>
<h3>How do we get from<br/>a shape to colored pixels</h3>
<br/>
<br/>
<canvas data-sample="spinning_wireframe_cube" class="float_left"></canvas>
<div class="float_left" style="line-height: 8; padding: 20px">to</div>
<canvas data-sample="lighted_spinning_textured_cube" class="float_left"></canvas>
<div class="float_left" style="line-height: 8; padding: 20px">?</div>
</section>
<section>
<h2>Rasterization: Shapes -> Pixels</h2>
<img src="https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Rasterisation-triangle_example.svg/450px-Rasterisation-triangle_example.svg.png">
</section>
<section>
<h2>Texture: UV Mapping</h2>
<p>Getting the value of the color...<p>
<img src="http://www.bcu.ac.uk/_media/img/nti/gamer_camp/blog_postings/UvMapping.jpg">
</section>
<section>
<h2>Lighting</h2>
<p>Getting the strength of the color...</p>
<br/>
<h3>Ambient, Diffuse, Specular</h3>
<canvas class="float_left" data-sample="lighted_ambient_sphere"></canvas>
<canvas class="float_left" data-sample="lighted_diffuse_sphere"></canvas>
<canvas class="float_left" data-sample="lighted_specular_sphere"></canvas>
</section>
<section>
<h2>Materials</h2>
<canvas class="float_left" data-sample="lighted_sphere"></canvas>
<canvas data-sample="lighted_textured_sphere"></canvas>
<p>Combining all lighting and textures for the final color</p>
</section>
<section>
<h2>
Coloring the pixels:<br/>
Texture and Lighting
</h2>
<br/>
<canvas data-sample="spinning_wireframe_cube" class="float_left"></canvas>
<img class="float_left" style="width: 20%"
src="https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Rasterisation-triangle_example.svg/450px-Rasterisation-triangle_example.svg.png">
<canvas data-sample="lighted_spinning_textured_cube" class="float_left"></canvas>
</section>
<section>
<h2>But how do we ...</h2>
<br/>
<br/>
<h3>figure out the amount of light?</h3>
<blockquote>Putting the rgba in a pixel's RGBA</blockquote>
</section>
</section>
<section>
<section>
<h2>Welcome BACK to Linear Algebra</h2>
<br/>
<img src="http://cronwtf.github.com/images/wtf.jpg">
</section>
<section>
<h2>The Normal</h2>
<img class="white_bg" src="https://encrypted-tbn3.google.com/images?q=tbn:ANd9GcSQyYxnsLVkIT5QpVBGJ00IDOcIrLPMPUXIyabQYuXZQxOuIGKN">
</section>
<section>
<h2>Lighting</h2>
<img src="images/shader_vectors.gif">
</section>
<section>
<h2>The Dot Product</h2>
<!-- <img class="white_bg" src="http://upload.wikimedia.org/wikipedia/commons/thumb/3/3e/Dot_Product.svg/300px-Dot_Product.svg.png"> -->
<img class="white_bg" src="http://cdn.wolfire.com/blog/linear/dotsimple.jpg">
</section>
<section>
<h2>Lighting</h2>
<img class="white_bg" src="http://math.hws.edu/graphicsnotes/c4/light_eq.png">
<br/>
<br/>
<ul>
<li>N * L = dot product</li>
<li>color.rgb * dot product = amount of color</li>
</ul>
</section>
<section>
<h2>Lighting Demystified (somewhat)</h2>
<canvas data-sample="lighted_sphere"></canvas>
</section>
</section>
<section>
<section>
<h2>Graphic Pipelines: How it started</h2>
<h3>Software Rendering</h3>
<img style="width: 480px;" src="http://1.bp.blogspot.com/-tQMjfiveb88/T5HvOfXc63I/AAAAAAAAB38/P_Nmtyw7-v8/s1600/prince-of-persia.gif">
<ul>
<li>Entirely done on CPU</li>
<li>Unaided by graphics hardware</li>
<li>Ultimate flexibility</li>
</ul>
</section>
<section>
<h3>How it was: Fixed Function Pipeline</h3>
<img src="http://cdn.steampowered.com/v/gfx/apps/2310/0000002448.600x338.jpg?t=1343157013">
<img src="http://www.techspot.com/reviews/hardware/voodoo3-3000/box_p.jpg">
<small style="font-size: 10px; display: block;">I couldn't find an image of a voodoo 1 card</small>
</section>
<section>
<h3>How it was: Fixed Function Pipeline</h3>
<img src="http://www.many-core.group.cam.ac.uk/platforms/pipeline_big.png">
<ul>
<li>Introduction of GPU hardware support</li>
<li>Sacrificed flexibility for speed</li>
</ul>
</section>
<section>
<h2>The Graphics Card</h2>
<img class="white_bg" src="http://www.sjbaker.org/wiki/images/thumb/3/31/Graphics_pipeline.png/800px-Graphics_pipeline.png">
</section>
<section>
<h3>How it is: Programmable Graphics Pipeline</h3>
<!-- <img src="http://chrisingradschool.files.wordpress.com/2010/03/screen-shot-2010-03-09-at-2-13-26-pm.png?w=600&h=279"> -->
<img src="http://www.many-core.group.cam.ac.uk/platforms/pipeline_big.png">
</section>
<section>
<h3>How it is: Programmable Graphics Pipeline</h3>
<img src="http://chrisingradschool.files.wordpress.com/2010/03/screen-shot-2010-03-09-at-2-13-26-pm.png?w=600&h=279">
</section>
</section>
<section>
<section>
<h1>What is WebGL?</h1>
<p>OpenGL ES2.0 port built into the <canvas> DOM element</p>
<canvas data-sample="webgl_spinning_colored_cube" style="display:inline"></canvas>
</section>
<section>
<h3>wtf</h3>
<pre class="supersmall float_left" style="width:50%"><code>
function init(scene) {
// Initialize
var gl = WebGLUtils.setupWebGL(scene.canvas);
if (!gl) {
return;
}
scene.program = simpleSetup(
gl,
// The ids of the vertex and fragment shaders
"vshader", "fshader",
// The vertex attribute names used by the shaders.
// The order they appear here corresponds to their index
// used later.
[ "vNormal", "vColor", "vPosition"],
// The clear color and depth values
[ 0, 0, 0, 0 ], 10000);
// Set up a uniform variable for the shaders
gl.uniform3f(gl.getUniformLocation(scene.program, "lightDir"), 0, 0, 1);
// Create a box. On return 'gl' contains a 'box' property with
// the BufferObjects containing the arrays for vertices,
// normals, texture coords, and indices.
scene.box = makeBox(gl);
// Set up the array of colors for the cube's faces
var colors = new Uint8Array(
[ 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, // v0-v1-v2-v3 front
1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, // v0-v3-v4-v5 right
0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, // v0-v5-v6-v1 top
1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, // v1-v6-v7-v2 left
1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, // v7-v4-v3-v2 bottom
0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1 ] // v4-v7-v6-v5 back
);
// Set up the vertex buffer for the colors
scene.box.colorObject = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, scene.box.colorObject);
gl.bufferData(gl.ARRAY_BUFFER, colors, gl.STATIC_DRAW);
// Create some matrices to use later and save their locations in the shaders
scene.mvMatrix = new J3DIMatrix4();
scene.u_normalMatrixLoc = gl.getUniformLocation(scene.program, "u_normalMatrix");
scene.normalMatrix = new J3DIMatrix4();
scene.u_modelViewProjMatrixLoc =
gl.getUniformLocation(scene.program, "u_modelViewProjMatrix");
scene.mvpMatrix = new J3DIMatrix4();
// Enable all of the vertex attribute arrays.
gl.enableVertexAttribArray(0);
gl.enableVertexAttribArray(1);
gl.enableVertexAttribArray(2);
// Set up all the vertex attributes for vertices, normals and colors
gl.bindBuffer(gl.ARRAY_BUFFER, scene.box.vertexObject);
gl.vertexAttribPointer(2, 3, gl.FLOAT, false, 0, 0);
gl.bindBuffer(gl.ARRAY_BUFFER, scene.box.normalObject);
gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0);
gl.bindBuffer(gl.ARRAY_BUFFER, scene.box.colorObject);
gl.vertexAttribPointer(1, 4, gl.UNSIGNED_BYTE, false, 0, 0);
// Bind the index array
gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, scene.box.indexObject);
return gl;
}
</code></pre>
<pre class="supersmall float_left" style="width:50%"><code>
function reshape(scene, gl) {
var canvas = scene.canvas;
// Set the viewport and projection matrix for the scene
gl.viewport(0, 0, canvas.width, canvas.height);
scene.perspectiveMatrix = new J3DIMatrix4();
scene.perspectiveMatrix.perspective(30, canvas.width/canvas.height, 1, 10000);
scene.perspectiveMatrix.lookat(0, 0, 7, 0, 0, 0, 0, 1, 0);
}
function drawPicture(scene, gl) {
// Make sure the canvas is sized correctly.
reshape(scene, gl);
// Clear the canvas
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
// Make a model/view matrix.
scene.mvMatrix.makeIdentity();
scene.mvMatrix.rotate(20, 1,0,0);
scene.mvMatrix.rotate(scene.currentAngle, 0,1,0);
// Construct the normal matrix from the model-view matrix and pass it in
scene.normalMatrix.load(scene.mvMatrix);
scene.normalMatrix.invert();
scene.normalMatrix.transpose();
scene.normalMatrix.setUniform(gl, scene.u_normalMatrixLoc, false);
// Construct the model-view * projection matrix and pass it in
scene.mvpMatrix.load(scene.perspectiveMatrix);
scene.mvpMatrix.multiply(scene.mvMatrix);
scene.mvpMatrix.setUniform(gl, scene.u_modelViewProjMatrixLoc, false);
// Draw the cube
gl.drawElements(gl.TRIANGLES, scene.box.numIndices, gl.UNSIGNED_BYTE, 0);
scene.currentAngle += scene.incAngle;
if (scene.currentAngle > 360)
scene.currentAngle -= 360;
}
window.samples.webgl_spinning_cube = {
initialize: function(canvas) {
var scene = { canvas: canvas };
canvas.addEventListener('webglcontextlost', handleContextLost, false);
canvas.addEventListener('webglcontextrestored', handleContextRestored, false);
canvas.width = sample_defaults.width;
canvas.height = sample_defaults.height;
var gl = init(scene);
if (!gl) {
return;
}
scene.currentAngle = 0;
scene.incAngle = 0.5;
var requestId;
function animate() {
drawPicture(scene, gl);
requestId = window.requestAnimFrame(animate, canvas);
}
animate();
function handleContextLost(e) {
e.preventDefault();
if (requestId !== undefined) {
window.cancelAnimFrame(requestId);
requestId = undefined;
}
}
function handleContextRestored() {
init(scene);
animate();
}
}
</code></pre>
</section>
<section>
<h2>What we care about</h2>
<ol>
<li>Setup on CPU</li>
<li>Vertex Processor <b>(vertices -> shapes)</b></li>
<li>Fragment Processor <b>(pixels -> colored pixels)</b></li>
</ol>
<img class="white_bg" src="http://www.sjbaker.org/wiki/images/thumb/3/31/Graphics_pipeline.png/800px-Graphics_pipeline.png">
</section>
<section>
<h2>CPU: Javascript</h2>
<pre class="code medium"><code class="javascript">
var gl = WebGLUtils.setupWebGL(scene.canvas);
scene.program = simpleSetup(
gl,
"webgl_vshader", // id of the vertex shader
"webgl_bland_fshader", // id of fragment shader
[ "vPosition"], // Vertex attribute used by the shader
[ 0, 0, 0, 0 ], 10000); // The clear color and depth values
scene.box = makeBox(gl);
// Set up the vertex buffer
gl.bindBuffer(gl.ARRAY_BUFFER, scene.box.vertexObject);
...
</code></pre>
</section>
<section>
<h2>CPU: Javascript</h2>
<pre class="code medium" style="font-size:19px;"><code class="javascript">
function drawPicture(scene, gl) {
// Clear the canvas
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
// Construct the model-view * projection matrix
scene.mvpMatrix.load(scene.perspectiveMatrix);
scene.mvpMatrix.multiply(scene.mvMatrix);
// Pass the moel-view-proj matrix in to the Shaders
scene.mvpMatrix.setUniform(gl, scene.u_modelViewProjMatrix, false);
// Draw the cube
gl.drawElements(gl.TRIANGLES, scene.box.numIndices, gl.UNSIGNED_BYTE,0);
}
</code></pre>
</section>
<section>
<h2>Vertex Processor: Vertex Shader</h2>
<pre style="font-size:18px; line-height: 24px;" class="code"><code class="javascript">
uniform mat4 u_modelViewProjMatrix; // Passed in from CPU
attribute vec4 vPosition; // Information from vertex
void main()
{
gl_Position = u_modelViewProjMatrix * vPosition;
}
</code></pre>
<img class="float_left" style="width: 20%"
src="images/Vertices.png">
<canvas data-sample="webgl_spinning_wireframe_cube" style="display:inline"></canvas>
</section>
<section>
<h3>Fragment Processor: Fragment Shader</h3>
<pre style="font-size:18px; line-height: 24px;" class="code"><code class="javascript">
void main()
{
gl_FragColor = vec4(1, 1, 1, 1); // RGBA
}
</code></pre>
<img class="float_left" style="width: 30%"
src="https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Rasterisation-triangle_example.svg/450px-Rasterisation-triangle_example.svg.png">
<canvas data-sample="webgl_spinning_bland_cube" style="display:inline"></canvas>
</section>
<section>
<h2>GLSL</h2>
<br/>
<br/>
<ul>
<li>OpenGL Shading Language (GLSL): A high-level shading language based on the syntax of the C programming language.</li>
</ul>
</section>
<section>
<h2>Vertex Shader</h2>
<pre style="font-size:18px; line-height: 24px;" class="code"><code class="cpp">
uniform mat4 u_modelViewProjMatrix; // Passed in from CPU
uniform mat4 u_normalMatrix;
uniform vec3 lightDir;
attribute vec3 vNormal; // Received from Vertex Buffer
attribute vec4 vPosition;
varying float v_Dot; // Variables output to Fragment Shader
varying vec4 v_Color;
void main()
{
gl_Position = u_modelViewProjMatrix * vPosition;
v_Color = vec4(1, 1, 1, 1); // White
vec4 transNormal = u_normalMatrix * vec4(vNormal, 1);
v_Dot = max(dot(transNormal.xyz, lightDir), 0.0);
}
</code></pre>
</section>
<section>
<h3>Fragment Shader</h3>
<br/>
<pre style="font-size:18px; line-height: 24px;" class="code"><code class="cpp">
varying float v_Dot; // Passed in from Vertex Shader via Rasterizer
varying vec4 v_Color;
void main()
{
gl_FragColor = vec4(v_Color.xyz * v_Dot, v_Color.a);
}
</code></pre>
<canvas data-sample="webgl_spinning_colored_cube" style="display:inline"></canvas>
</section>
</section>
<section>
<section>
<h1>What is ThreeJS?</h1>
<blockquote class="medium" style="margin-top: 80px; width: 100%">
The aim of the project is to create a lightweight 3D library with a very low level of complexity — in other words, for dummies.
<br/>
The library provides <canvas>, <svg> and WebGL renderers.
</blockquote>
<canvas data-sample="lighted_spinning_cube"></canvas>
</section>
<section>
<h3>Intro to ThreeJS: Spinning Cube</h3>
<pre class="code"><code>
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera( 30, width / height, 1, 1000 );
camera.position.set(0, 3, 7);
camera.lookAt( new THREE.Vector3(0,0,0));
var scale = 2.5;
var geometry = new THREE.CubeGeometry( scale, scale, scale );
var material = new THREE.MeshBasicMaterial( { color: 0xdddddd } );
var mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );
var renderer = new THREE.WebGLRenderer({canvas: canvas, antialias: true});
renderer.setSize( width, height );
function animate() {
requestAnimationFrame( animate, canvas );
mesh.rotation.y += 0.008;
renderer.render( scene, camera );
}
animate();
}
</code></pre>
<p class="supersmall">16 lines of code</p>
</section>
<section>
<h3>Scene</h3>
<pre class="medium"><code>
var scene = new THREE.Scene();
</code></pre>
<br/>
<p>Encapsulates everything with regard to this rendering</p>
<ul>
<li>Matrices</li>
<li>Camera</li>
<li>Models</li>
</ul>
</section>
<section>
<h3>Camera</h3>
<pre class="medium"><code>
var camera = new THREE.PerspectiveCamera(30, width/height, 1,1000);
camera.position.set(0, 3, 7);
camera.lookAt( new THREE.Vector3(0,0,0));
</code></pre>
<img src="http://robertokoci.com/images/posts/graphics/game/programming/matrix-unveiled/ProjectionMatrix.png">
</section>
<section>
<h3>Geometry</h3>
<pre class="medium"><code>
var scale = 2.5;
var geometry = new THREE.CubeGeometry( scale, scale, scale );
</code></pre>
<img class="white_bg" src="http://obviam.net/wp-content/uploads/2011/01/Vertices.png">
</section>
<section>
<h3>Materials</h3>
<pre class="medium"><code>
var material = new THREE.MeshBasicMaterial({ color: 0xdddddd });
</code></pre>
<p>Encapsulates:</p>
<ul>
<li>Texture</li>
<li>Attributes</li>
<li>Shaders</li>
</p>
</section>
<section>
<h3>Mesh</h3>
<pre class="medium"><code>
var mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );
</code></pre>
<br/>
<ul>
<br/>
<li>geometry: Vertices -> Shapes</li>
<li>material: Pixels -> Colored Pixels</li>
<br/>
<li>World Matrix</li>
</ul>
</section>
<section>
<h3>Renderer</h3>
<pre class="medium"><code>
var renderer = new THREE.WebGLRenderer({canvas: canvas});
renderer.setSize( width, height );
</code></pre>
<br/>
<canvas data-sample="wireframe_plane"></canvas>
</section>
<section>
<h3>request Animation Frame?</h3>
<p>Welcome to the Render Loop</p>
<pre class="medium"><code>
function animate() {
requestAnimationFrame( animate );
mesh.rotation.y += 0.008;
renderer.render( scene, camera );
}
animate();
</code></pre>
<canvas data-sample="spinning_cube"></canvas>
</section>
<section>
<h2>Materials: Phong</h2>
<p>TODO: Add Light</p>
<pre class="medium"><code>
var material = new THREE.MeshPhongMaterial({ color: 0xdddddd });
...
var directionalLight = new THREE.DirectionalLight ( 0xffffffff );
directionalLight.position.set(0, 3, 7);
scene.add( directionalLight );
</code></pre>
<canvas data-sample="todo_lighted_spinning_cube"></canvas>
</section>
<section>
<h3>Materials: Texture</h3>
<p>TODO: Add Texture</p>
<pre class="medium"><code>
var texture = THREE.ImageUtils.loadTexture(
'images/checker_large.gif',
{},
function() {
animate();
}
);
//var material = new THREE.MeshPhongMaterial({ color: 0xdddddd });
var material = new THREE.MeshPhongMaterial({ map: texture });
</code></pre>
<canvas data-sample="todo_lighted_spinning_textured_cube"></canvas>
</section>
</section>
<section>
<section>
<h2>ThreeJS: Loading Meshes</h2>
<p>Credit for model goes to <a href="http://www.blendswap.com/?author=3134">Chris Kuhn</a></p>
<canvas data-sample="load_startrek_enterprise"></canvas>
</section>
<section>
<h2>Blender and ThreeJS</h2>
<br/>
<ul>
<li>Grab models from <a href="http://www.blendswap.com/blends/vehicles/star-trek-collection/">Blendswap: Startrek Collection</a></li>
<li>Blender: Content creation tool for 3D models</li>
<li>Can export to the Three js file format</li>
<li><a href="js/meshes/Startrek_Enterprise.js">Startrek Enterprise Mesh JSON</a></li>
</ul>
</section>
<section>
<h2>ThreeJS: Importing Mesh</h2>
<br/>
<pre class="medium"><code>
// REMOVED
// var geometry = new THREE.CubeGeometry( 70, 70, 70 );
// var material = new THREE.MeshBasicMaterial({color: 0xdddddd});
var loader = new THREE.JSONLoader();
loader.load("js/meshes/Startrek_Enterprise.js", function(geometry) {
mesh = new THREE.Mesh( geometry, geometry.materials[0] );
scene.add( mesh );
...
</code></pre>
</section>
<section data-state="loaded_apache">
<h2>with Textures</h2>
<p>Credit for model goes to <a href="http://www.blendswap.com/?author=3134">Chris Kuhn</a></p>
<a href="images/FinalApacheTexture.png">Apache Texture File</a>
<canvas data-sample="load_apache"></canvas>
</section>
</section>
<section>
<section>
<h2>ThreeJS: Particles</h2>
<canvas data-sample="particles"></canvas>
</section>
<section>
<h2>Primitives</h2>
<img style="width:850px;" src="http://3dgep.com/wp-content/uploads/2011/02/OpenGL-Primitives.png">
</section>
<section>
<h2>ThreeJS: Particles</h2>
<pre class="code medium"><code class="cpp">
geometry = new THREE.Geometry();
for ( i = 0; i < 20000; i ++ ) {
var vertex = new THREE.Vector3();
vertex.x = Math.random() * 2000 - 1000;
vertex.y = Math.random() * 2000 - 1000;
vertex.z = Math.random() * 2000 - 1000;
geometry.vertices.push( vertex );
}
</code></pre>
<br/>
<pre class="code medium"><code class="cpp">
particles = new THREE.ParticleSystem( geometry, materials[i] );
scene.add( particles );
</code></pre>
</section>
<section>
<canvas data-sample="particles"></canvas>
<h2>Only 20k, how about a million?</h2>
<ul>
<li><a href="http://mrdoob.com/lab/javascript/webgl/particles/magicdust.html">Magic Dust Particles</a></li>
<li><a href="http://www.html5rocks.com/en/tutorials/webgl/million_letters/million_letters.html">A Million Letters</a></li>
</ul>
</section>
</section>
<section>
<section>
<h2>ThreeJS: Normal Mapping</h2>
<p>Using the RGB for your <b><u>normal's</u></b> XYZ</p>
<canvas data-sample="normal_mapped_plane" class="float_left" style="display:inline"></canvas>
<canvas data-sample="wireframe_plane" class="float_left" style="display:inline"></canvas>
<img src="images/normal_map_tile.jpg" class="float_left normal_map" style="width:200px">
</section>
<section>
<h3>Old school: Per Vertex Lighting</h3>
<canvas data-sample="per_vertex_lighting"></canvas>
</section>
<section>
<h2>New school: Per Pixel Lighting</h2>
<br/>
<img class="float_left" style="width: 25%"
src="https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Rasterisation-triangle_example.svg/450px-Rasterisation-triangle_example.svg.png">
<!-- <img style="width: 70%" src="images/reflection_vector.gif"> -->
<img class="white_bg" src="http://math.hws.edu/graphicsnotes/c4/light_eq.png">
</section>
<section>
<h2>Normal Map</h2>
<img src="images/normal_map_tile.jpg">
</section>
<section>
<h2>Normal Map</h2>
<canvas data-sample="normal_mapped_plane" class="float_left" style="display:inline"></canvas>
<canvas data-sample="wireframe_plane" class="float_left" style="display:inline"></canvas>
<img src="images/normal_map_tile.jpg" class="float_left normal_map" style="width:200px">
</section>
<section>
<h2>ThreeJS: Custom Shaders</h2>
<pre class="code medium"><code class="javascript">
// Grab shader code
var vertexShader = $('#normal_map_vs').text();
var fragmentShader = $('#normal_map_fs').text();
// Configure material parameters
var parameters = {
// Shaders
fragmentShader: fragmentShader,
vertexShader: vertexShader,
// Shader Data
uniforms: uniforms,
attributes: attributes
};
// Create custom shader material
var normal_material = new THREE.ShaderMaterial( parameters );
// Add mesh
var mesh = new THREE.Mesh( geometry, normal_material );
scene.add( mesh );
</code></pre>
</section>
<section>
<h2>Showcase: Skin Material</h2>
<a href="http://mrdoob.github.com/three.js/examples/webgl_materials_bumpmap_skin.html">WebGL Skin Material</a>
</section>
</section>
<section>
<section>
<h2>ThreeJS: Post-Processing</h2>
<br/>
<br/>
<canvas class="float_left" data-sample="spinning_textured_cube"></canvas>
<canvas data-sample="blur_post_process"></canvas>
</section>
<section>
<h2>Render to Texture</h2>
<canvas data-sample="render_to_texture"></canvas>
<pre class="code medium"><code class="javascript">
var renderTarget = new THREE.WebGLRenderTarget(
sample_defaults.width,
sample_defaults.height,
renderTargetParameters);
...
renderer.render( worldScene, camera, renderTarget );
planeMaterial.uniforms[ "tDiffuse" ].texture = renderTarget;
renderer.render( planeScene, camera );
</code></pre>
</section>
<section>
<h2>2 Pass Blurring</h2>
<img src="http://www.gamerendering.com/wp-content/uploads/image13-bluring.jpg">
</section>
<section>
<p>Multiple passess...</p>
<br/>
<pre class="code medium"><code class="javascript">
var composer = new THREE.EffectComposer( renderer );
// 3 Passes...
var renderModel = new THREE.RenderPass(scene, camera);
var horizontalBlur = new THREE.ShaderPass(horizontalBlurShaders);
var verticalBlur = new THREE.ShaderPass(verticalBlurShaders);
verticalBlur.renderToScreen = true;
composer.addPass( renderModel );
composer.addPass( horizontalBlur );
composer.addPass( verticalBlur );
...
// renderer.render( scene, camera ); REMOVED