3D –graphics and animation About modeling…
Harri Airaksinen;
3D –graphics and animation About modeling…
Harri Airaksinen;
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?
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
3D Studio Max - DXF
0
SECTION
2
HEADER
9
$ACADVER
1
AC1021
9
$ACADMAINTVER
70
1
9
$DWGCODEPAGE
3
ANSI_1252
9
$INSBASE
10
0.0
20
… and so on
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? “
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
Modeling; polygons
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…
Perspective
Projection plane
Parallel projection – perspective angle
Perspective can be controlled via camera lenses
One more thing about scene
You can fix your user 3D modeling user interface – don’t do before you know what you do!
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)
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
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
Sketches - drafts
Pen sketches and the final
model Final Year project; Panu Aatrokoski - Seikkailupeli Odot Tamat On (2007)
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
Controlling lines
Controlling lines – 3D Studio Max
Modifier – and mouse right button Circle -> Modifier ->
house right button -> convert to
editable…
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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