3D – Modelingfor Computer Games

Uni UlmComputerspiele Seminar

Summer SemesterDiego Montoya Orozco

Master IST mtkl. 716654

3D - Modeling for Computer Games – Computer Games Seminar 2

Summary

● Why Model in 3D?

● 3D - Representation– Box Modeling

– Bézier Curves

– B-Splines

– NURBS

– Softening with Splines

– Particle Modeling

● 3D – Scan– Contact Scanner

– Non-Contact Scanner

● Texture Mapping– Bump Mapping

– Texture Synthesis

– Anti-Aliasing

● For the future

3D - Modeling for Computer Games – Computer Games Seminar 3

Why Model in 3D?

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3D - Representation

● Solid vs. Shell

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Box Modeling

● Extrude, scale, rotate, translate

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Box Modeling

3D - Modeling for Computer Games – Computer Games Seminar 7

Box Modeling

3D - Modeling for Computer Games – Computer Games Seminar 8

Box Modeling

3D - Modeling for Computer Games – Computer Games Seminar 9

Box Modeling

3D - Modeling for Computer Games – Computer Games Seminar 10

Box Modeling

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Box Modeling

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Bézier Curves● Parametric, soft

● Degree depends on # of control points

● Patching is used

B u =∑k=0

N

P kN !

k ! N−k !uk 1−u N−k

0u1

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B-Splines

● Interpolating, soft, piece-wise built using base functions.

● Degree doesn't depend on control points● Cd-2 continuity

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NURBS

● Generalization of B-Splines and Bézier curves● Non Uniform, two parameters 'u','v' to create

surface.● Base function family recursively built

N i , n= f i N i , n−1 g i1, nN i1,n−1

f i , nu =u−k ik in−k i

g i , nu=k in−u

k in−k i

C u=∑i=1

k N i ,n wi

∑j=1

k

N j ,n w j

P i=∑i=1

k

N i , nw i

∑j=1

k

N j ,nw j

P i

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Softening with Splines

3D - Modeling for Computer Games – Computer Games Seminar 16

Softening with Splines

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Particle Modeling

● Stochastic models, shows after rendering● Attributes:

– Position, velocity, color, lifetime, age, shape, size, weight, etc...

● Snow vs. hair

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3D – Scan: Contact Scanner

● Hand Operated

● Automatic

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3D – Scan: Non-Contact Scanner

● Active– Time of light

– Triangulation

– Structured Light

● Passive– Stereoscopic

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Texture Mapping

● Possibilities and Problems● Affine Mapping Problem

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Bump Mapping

● Tactile feeling, high detail● Surface map determines normal offset

+ =

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Texture Synthesis

● Regular to stochastic textures.● Patch-Based algorithm

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Anti-Aliasing

● Caused by high frequencies● Solutions: Filtering, super- and multi-sampling

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For the future

● More power and memory● Motion and image recognition controllers

(to aide design?)● 3D Televisions, and of course, 3D Videogames

Backwards Compatibility!!!

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Thank you