1. Emerging Technologies for Games Review & Revision Strategy
CO3303

2. Exam Overview
Third year exams have a different focus than second year exams:
2nd year: Explain process X; Describe concept Y
3rd year, some of the above, but also: Evaluate process X for use in situation Y; Compare techniques A & B
Some marks for explaining module content
But many marks for being able to evaluate what you have learnt
Discussing topics rather than repeating them
Applies to a greater or lesser extent to all exams

3. Exam Structure Structure of this module’s exam:
Answer four questions out of six
25% each question
Three hour exam
Some questions might have many parts
Still may require some lengthy answers
Questions with few parts require considerable depth of discussion
In any case, each mark is awarded for making a distinct point
Rarely useful to repeat yourself

4. Topics: Quaternions / Animation
Comparison of methods to store rotations
Euler angles, Matrices, Angle-axis form & Quaternions
Form of a quaternion with formulae
Using quaternions (formulae in grey):
Conversions, addition & scaling
Combining quaternions, rotating vectors
Linear interpolation of transforms
Position / scaling; problems with rotation

5. Quaternions / Animation 2
Normalised linear interpolation (nlerp)
Spherical linear interpolation (slerp)
Discussion of basic and derived formulae
Animation:
Storage issues
Transformation decomposition
Keyframes
Use of interpolation for in-between frames
Multiway blending
Bone masks
Motion extraction

6. Optimisation Rationale for optimisation in games
How and when to apply optimisation
And when not to optimise
Types of optimisation
Speed, memory, bandwidth etc
Optimisation techniques
Loop unrolling, removing constant calculations etc.
Applied techniques - may be given code to optimise
Data structure and algorithm choice
Memory / Cache Optimisation

7. Batching & Instancing State changes; impact on render performance
Improving rendering process wrt state changes
Batch size; impact on render performance
Examples
Instancing
As a technique to render multiple models
As a method to reduce batch sizes & state changes
Use of geometry shader for camera-facing particles

8. Spatial Partitioning Rationale and uses for partitioning
PVS for general partition schemes
Generation, use & limitations
Portal based partitions
Usage, refinements, pros & cons
BSP trees
Construction, point location, use, pros & cons
Quadtrees / Octrees
Creation, location, usage, loose quadtrees
Diagrams common in partitioning questions

9. Post Processing Front / back buffer usage, swap chains, VSync
Render targets, post-processing, multiple render passes
Post processing techniques:
Colour filters, blur, bloom, distortion, depth of field, feedback
Explanation of algorithms used for the above
Full screen / Area / Polygon processing
Adjustments required for each
Diagrams essential in this topic

10. DirectX 10 Overview of changes for DX10 Geometry Shader
How it fits in the rendering pipeline
Basic purpose / usage
Simple geometry shader techniques
Stream Output Stage
Purpose / Usage
Location in pipeline
Example of use (e.g. GPU particles)

11. Linear Dynamics / Particle Physics
Initial value methods:
Definition of and need for
Euler’s method, Mid-point method, Verlets
Relative benefits/drawbacks
Equations for each
Do not need to derive equations though
Connected particle systems:
Spring formula (Hooke’s law)
Other connector types
Solving constraints
Application to skinning

12. Miscellaneous Techniques
Covered very specific techniques for:
Deferred Rendering
Tessellation
Water Rendering
Soft particles & sorting blended polygons
Questions may cover theory and practice of these methods

13. Example Questions
i) Explain how full-screen post-processing effects are performed in general. Illustrate your answer with a diagram
ii) Describe a process to produce a depth of field effect using post-processing
i) Explain the terms lerp, nlerp and slerp. Provide the formulae relevant to your answer.
ii) Discuss the advantages and disadvantages of nlerp & slerp for animation of rotations
Further examples provided on past paper and worksheet