Lecture 20

Scene Graph

Quaternions

Skeletons

Object Oriented

Slerp

Animations

Textures

Anaglyph

Robot

Head

Neck

Torso

Lower Arm

Upper Arm

Hand

Upper Arm

Lower Arm

Hand

Upper Leg

Lower Leg

Foot

Head

Object Frame

Neck

Torso

Upper Arm

Lower Arm

Hand

neck.position.y = -10;

torso.position.y = -30;

-10

-40

left_upper_arm.position.y = -5;
left_upper_arm.position.x = 5;

left_lower_arm.position.y = -15;
left_lower_arm.position.x = 5;

left_hand.position.y = -5;
left_hand.position.x = 5;

Position is relative to parent!

Head

Upper Arm

q (0, 0, 0, 1)

Identity

q2 (Math.sin(T/2),

Math.cos(T/2))

Rotate 180° in X

T = Math.PI

Arm down

Arm up

Time

Frames

Keyframe 2

Keyframe 1

slerp Interpolation

Lecture 21

Skinning

http://doc.gold.ac.uk/msccge/alumni/KesterSheridan/Solidsight/implementation.htm

Skeleton -> Mesh

Rigging

https://www.youtube.com/watch?v=cp1YRaTZBfw

Mesh -> Skeleton

Kinematics

Forward Kinematics

Inverse Kinematics

Move down the scene graph

Move up in the scene graph

Upper Arm

Hand

Upper Arm

Hand

Upper Arm

Hand

Multiple Solutions!

Lecture 22

http://allyssaalewis.com/

Lecture 23

Time

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
    <title>CS460 Computer Graphics at the University of Massachusetts Boston</title>
    <script type="text/javascript" src="../../js/xtk_edge.js"></script>
    <link rel="stylesheet" type="text/css" href="../../styles/fonts.css"/>
    <style>
      html, body { 
        background-color:#000;
        margin: 0;
        padding: 0;
        height: 100%;
        overflow: hidden !important;  
        font-family: din_condensed;
        font-size: 18pt;
      }
    </style>

    <script type='text/javascript'>
      window.onload = function() {

        // create a new test_renderer
        r = new X.renderer3D();
        r.init();
        
        // UMASS BOSTON
        //
        // create a cube
        umassboston = new X.cube();
        // skin it..
        umassboston.texture.file = 'umassboston.png';
        // hide it for now!
        umassboston.visible = false;

        r.add(umassboston);


        // BOSTON GFX
        //
        // create a cube
        bostongfx = new X.cube();
        // skin it..
        bostongfx.texture.file = 'bostongfx.png';
        // hide it for now!
        bostongfx.visible = false;

        r.add(bostongfx);

        // setup the camera
        r.camera.position = [00, 00, 60];
        
        // .. and render it
        r.render();
        
      };

      clicked = false;
      window.onclick = function() {
        
        if (clicked) return; // sometimes you click again by accident,
                             // and restart the animation.. let's not!

        // we need user feedback, to allow the music to play..
        // let's do it on click!
        clicked = true;
        animation();

      }


      function animation() {

        // start the music
        var music = document.getElementById('music');
        music.autoplay = true;
        music.load();

        setTimeout(function() {
          umassboston.visible = true;
        }, 400);
        
        setTimeout(function() {
          umassboston.visible = false;
          r.camera.position = [0, 0, -25];
          bostongfx.visible = true;
        }, 3200);

        setTimeout(rotate_bostongfx, 6200);

      };



      function rotate_bostongfx() {

        var rotateCounter = 0;

        var spinner1 = setInterval(function(){
          rotateCounter += 1;

          // console.log(rotateCounter*2);
          if (rotateCounter*2 >= 90) {
            clearInterval(spinner1); // this is not time-based now...

            bostongfx.visible = false;

            // now the real CS460 logo..
            create_cs460_logo();
            return;

          }

          bostongfx.transform.rotateY(rotateCounter*2);
        },100);



      };



      function create_cs460_logo() {

        document.getElementById('caption').style.display = 'block';

        // create a new X.object
        cs460logo = new X.object();

        // add the points, normals and colors
        //
        // this means 648000 / 3 == 216000 vertices
        // on my work machine I could set 24000000 / 3 == 8 mio vertices
        cs460logo.points = new X.triplets(648000);
        cs460logo.normals = new X.triplets(648000);
        cs460logo.colors = new X.triplets(648000);
        
        // and set the type to POINTS
        cs460logo.type = 'POINTS';
        
        // create the points, normals and colors
        for ( var x = 0; x < 60; x++) {
          for ( var y = 0; y < 60; y++) {
            for ( var z = 0; z < 60; z++) {
              
              cs460logo.points.add(x, y, z);
              cs460logo.normals.add(1, 1, 1);
              cs460logo.colors.add(x/60, y/60, z/60);
              
            }
          }
        }
        
        // add the object
        r.add(cs460logo);

        // setup the camera
        r.camera.position = [500, 500, 500];

        setTimeout(zoom_into_cs460logo, 2000);
        
      };



      function zoom_into_cs460logo() {

        var zoomer = setInterval(function() {

          // we can stop once we are far away enough
          if (r.camera.view[14] > 1000) {
            clearInterval(zoomer); 
            // console.log('zooming done'); 

            setTimeout(function() {
              document.getElementById('caption').style.display = 'none';

              start_content();
            }, 2000);
            
            return;

          }

          // zoom in
          r.camera.zoomIn();

        }, 10);

      };


      function start_content() {

        // reduce music volume
        var music = document.getElementById('music');
        music.volume = .1;

        // activate speech
        var voice = document.getElementById('voice');
        voice.autoplay = true;
        voice.volume = 1;
        voice.load();

        frames = ['content1', 'content2', 'content3', 'content4', 'content5', null];
        times = [0, // Today... 
                 1000, // 
                 4200, // And
                 6000, // 
                 10000, // this is lecture 19
                 14000];

        //
        // this is (like the whole animation concept), a little hacky!!
        //
        for (var f in frames) {
    
          setTimeout(function(f) {
            
            if (f > 0) {
              document.getElementById(frames[f-1]).style.display = 'none';
            }

            if (frames[f] != null) {
              document.getElementById(frames[f]).style.display = 'block';
            } else {
              music.volume = .1;

              setTimeout(function(f) {
                fadeout = setInterval(function(f) {
                  if (music.volume <= 0.) {
                    clearInterval(fadeout);
                    return;
                  }
                  music.volume -= .05;
                  
                }, 500);
              },3000);

              
            }

          }.bind(this,f), times[f]);

        }

      };


    </script>
  </head>
  <body>
  <div style="visibility:hidden">
    <audio id='music'>
      <source src="bensound-evolution.mp3">
    </audio>
    <audio id='voice'>
      <source src="lecture23.mp3">
    </audio>
  </div>
  
  <div id='caption' style='display:none;position: absolute;color:white;top:45%;left:50%;margin-left:50px;font-size:440%'>CS460</div>

  <div id='content1' style='display:none;position: absolute;color:white;top:25%;left:30%;margin-left:50px;font-size:440%'>Today...</div>

  <div id='content2' style='display:none;position: absolute;color:white;top:30%;left:20%;margin-left:50px;font-size:440%'>We will learn more about animations..</div>

  <div id='content3' style='display:none;position: absolute;color:white;top:20%;left:10%;margin-left:50px;font-size:440%'>And...</div>

  <div id='content4' style='display:none;position: absolute;color:white;top:35%;left:20%;margin-left:50px;font-size:440%'>We will talk to an emmy winning prime-time animator!</div>

  <div id='content5' style='display:none;position: absolute;color:white;top:45%;left:40%;margin-left:50px;font-size:440%'>This is lecture 23.</div>    

  </body>
</html>

1. Setup

2. UMB
400 ms

3. GFX
3200 ms

3. rotate
6200 ms

4. CS460
180°

5. zoom
2000 ms

6. content
camera.z > 1000

7. end
XXX ms

Texture Mapping

width

height

Fragment Shader

Vertex Shader

vec2( )

vec3 a_Position;

vec2 a_TexCoord;

vec2 v_TexCoord;

0, 0

1, 1

0, 1

u, v

varying

vec2 v_TexCoord;

varying

sampler2D u_Sampler;

Sampling

https://learnopengl.com/Getting-started/Textures

Nearest Neighbor

Linear

Interpolation

https://threejs.org/examples/webgl_materials_video.html

Lecture 24

Lecture 25

Assignment 6

Normals

(x, y, z)

Vertex

/ Vertices

Face

N1 (x, y, z)

N2 (x, y, z)

Face

Normals

(x, y, z)

Vertex

/ Vertices

Face

N1 (x, y, z)

N2 (x, y, z)

Vertex

N3 (x, y, z)

N6 (x, y, z)

N5 (x, y, z)

N4 (x, y, z)

No Shading

Normals

used for Material

used for Lighting

No Normals

Face Normals

Vertex Normals

Bump Map

Normals

Pixel

  var mesh = new THREE.SkinnedMesh( geometry, material );
  var skeleton = new THREE.Skeleton( bones );
  mesh.add( bones[ 0 ] );
  mesh.bind( skeleton );

5 Skinned Meshes

5 Cylinder Geometries

Lecture 26

GLTF

.gltf

.glb

STL

OBJ

PLY

Collada

.dae

.stl

.ply

.obj

https://www.theobjects.com/dragonfly/dfhelp/30/Content/17_File%20Formats/Mesh%20File%20Formats.htm

And more:

Stereo Lithography (STL)

solid SOMENAME
   facet normal 1 0 0
      outer loop
         vertex 0 0 1
         vertex 1 0 0
         vertex 0 1 0
      endloop
   endfacet
   facet normal 1 0 0
      outer loop
         vertex 0 0 1
         vertex 1 1 0
         vertex 1 1 1
      endloop
   endfacet
   ...
endsolid

Face 1

Face 2

Stanford Polygon File (PLY)

ply
format ascii 1.0          
comment i love cs460
element vertex 4       
property float x          
property float y         
property float z      
element face 3
property list uchar int vertex_index 
end_header                 
0 0 0                      
0 0 1
0 1 1
0 1 0
3 0 1 2 
3 1 2 3
3 1 2 4

Vertices

Faces

Header

Wavefront Object (OBJ)

Vertices

Faces

v -0.5 -0.5 0.5
v 0.5 -0.5 0.5
v -0.5 0.5 0.5
v 0.5 0.5 0.5
v -0.5 0.5 -0.5
v 0.5 0.5 -0.5
v -0.5 -0.5 -0.5
v 0.5 -0.5 -0.5
f 1 2 4
f 1 4 3
f 3 4 6
f 3 6 5
f 5 6 8
f 5 8 7
f 7 8 2
f 7 2 1
f 2 8 6
f 2 6 4
f 7 1 3
f 7 3 8
f 7 3 5

Lecture 27

Light Simulations

N (x, y, z)

Material

Scattering

controls the physical appearance

http://lessons.goxtk.com/04/

magic mode uses (x, y, z) as color

https://threejs.org/docs/#api/en/materials/MeshNormalMaterial

https://threejs.org/examples/webgl_materials.html

Lecture 28

Light Simulations

N (x, y, z)

Material

Scattering

controls the physical appearance

+ Light

https://flylib.com/books/en/2.789.1.40/1/

Material

Light

Color

Direction

Color

Orientation

Two things control the color of an object

Physically Based Rendering

https://marmoset.co/posts/basic-theory-of-physically-based-rendering/

https://threejsfundamentals.org/threejs/threejs-lights-point.html

var color = 0xFFFFFF;
var intensity = 1;
var light = new THREE.PointLight(color, intensity);
light.position.set(0, 10, 0);
scene.add(light);

//...
gui.add(light, 'distance', 0, 40)

Lecture 29

Jasmine Roberts

Lecture 30

https://codesandbox.io/s/github/FNNDSC/ami/tree/master/lessons/01

Image Volumes

https://slicedrop.com

Slice-based Volume Rendering

https://slideplayer.com/slide/6545198/

https://journals.plos.org/plosone/article/figures?id=10.1371/journal.pone.0193636

Volume Rendering with Ray Casting

Cinematic Volume Rendering

https://undark.org/2016/07/01/medical-imaging-cinematic-rendering/

Marching Cubes creates 3D Meshes

Bill Lorensen 1987

Label Maps

Marching Cubes in 3D

Create triangles to approximate the shape

Inside

Outside

https://www.slideshare.net/tamarapinos/marching-cubes-21997366

Lecture 31

Lecture 32

Lecture 33

Lecture 34

Lecture 35

Lecture 36

Lecture 37

RateMyTalk.com/ECNP2H

Lecture 38 OLD

By Daniel Haehn

Lecture 38 OLD

Slides for CS460 Computer Graphics at UMass Boston. See https://cs460.org!

Daniel Haehn PRO

Hi, I am a biomedical imaging and visualization researcher who investigates how the study of brain connectivity and machine perception can help advance the understanding of biologically inspired artificial intelligence.

Lecture 38 OLD

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