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3D –graphics and animation

About modeling…

Harri Airaksinen;

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Modeling; coordination

Axels (right-handed coordination system) – fingers direction

Rectangular coordinate system or Cartesian coordination versa spherical or azimuthal coordinate system

Origon Direction of positive axels Global- and local coordination's. Where do

you need local coordinate system?

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Modeling; basic primitives

Different 3D systems has their own set of basic primitives and their parameters (value, can be integer or some other data), example: Cube: Height, width, length, color, surface material,

reflection, transparency – can you say any more?

How to transfer 3D models between different systems? It’s a hard business – there are standards, de-facto DXF

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3D Studio Max - DXF

0SECTION 2HEADER 9$ACADVER 1AC1021 9$ACADMAINTVER 70 1 9$DWGCODEPAGE 3ANSI_1252 9$INSBASE 100.0 20… and so on

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Modeling; mathematics

Math is behind everything …. specially in 3D Matrix- and array calculation (corner points and

surfaces between them) Spatial integrals Lightning models and algorithms Reflection and collision algorithms “Everything is already invented? “

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Modeling; surfaces

“There is no circle – only number of polygons”

The quality of display depends how you have set it up – more polygons = heavier model must optimize the models

Famous Utah teapot

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Modeling; polygons

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Modeling; editing

Editing means changing spatial matrix values Scaling (Uniform Scale/Non Uniform Scale) –

relative scaling or scaling via axel direction Moving (value can be given as absolute from global

coordinates or local movement from current location)

Rotating, remember right-handed coordinate system – take axel on your hand, finger will tell the positive rotation direction

Tools for editing (based on 3D system) – using mouse, keyboard, object lists…

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Perspective

Projection plane Parallel projection – perspective angle Perspective can be controlled via camera lenses

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One more thing about scene

You can fix your user 3D modeling user interface – don’t do before you know what you do!

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3D camera movement directions; terms

Names are coming from movie industry (think that camera is picturing you)

Dolly, a translation of the camera along its X (side direction) Tilt, a rotation of the camera around its X axis. May called  also a

pitch (as in airplanes pitching) Boom, a translation along its Y axis (up - down)

Pan (yaw), a rotation around its Y axis Truck, a translation along its Z axis (toward – away)

Roll, a rotation around its Z axis Zoom, a special type of camera move where only the

camera's simulated focal length is modified but its position and orientation remain untouched (same effect as truck)

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Anything else to remember?

• Save different versions of your 3D models• Remember backups Max’s autobackup/default 5 min. Customize Preference settings• File Set Project folder• File Summary info

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Sketches - drafts

Modeling starts with drawing sketches Pen and paper is still very good tools for

sketching Do you know how to draw, everybody can make

sketches Using 2D painting/drawing tools – use of

scanning Modeling dimensions – model allways using real

dimensions – what about if the model is kilometers wide? submodels

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Sketches - drafts

Final Year project; Panu Aatrokoski - Seikkailupeli Odot Tamat On (2007)

Pen sketches and the finalmodel

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The use of a line

Important basic primitive when you define 3D object shapes and other characteristics

Easy to create using today’s modeling tools Straight lines (polygonal lines) used to

create polygons and polygon meshes

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Controlling lines

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Controlling lines – 3D Studio Max

Modifier – and mouse right buttonCircle -> Modifier -> house right button -> convert toeditable…

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Modeling – input devices

Command nputs: Mouse -- 3D mouse --- & key board, still Digit tables (sketching and 2D – also 3D, if modeling

application supports)

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Short movies - Pixar

http://www.pixar.com/shorts/ http://profile.imeem.com/j6a57z/video/vBvL

51C-/pixar_the_birds/

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Surfaces and primitives

Surface Basic primitives Editing basic primitives Free form modeling

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Using 2D shapes to build 3D objects

Extrusion or sweeping) – 3D Studio Max, Lofting

• Line = path• Circle = out lines of the surface• Select path Compound Object Get Shape = Circle

Editing:• Modifier Deformation example. scale

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Using 2D shapes to build 3D objects

Lathe

• Edge line• Modifier Modifier List Lathe

Editing:• Modifier example. Axis

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Other methods to create surfaces

Editing basic primitives – editable meshes Mathematical models (Starr, random, fractal) Terrain Compound Object (3D Studio Max)

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Object parameters

Select object, mouse right, object parameter

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Handling objects

Locking – Freezing Hiding Copy or Instance or Reference object Mirror 3D -text

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Volume models

3D Studio Max makes surface models only

There are 3D applications, which can do volumetric modeling = cube is “solid” – closed, solid material. If you cut solid object, the cutting edges can be seen correctly