Game Engine Development

Several techniques I implemented during my 3D engine development class:

• Terrain Following: With several vector cross product computations, the dune buggy can be positioned and oriented to follow the terrain realistically.


• Maya Export Plug-in: By using the Maya Plug-in SDK, I wrote several plug-ins for Maya which can be used to export model and custom attributes into both XML and binary format.


• Collision Detect: AABB, Sphere, and K-DOP collision detecting techniques.


• Camera Views: Mouse-look, Look-At, Turn-to, Hard-attach, Soft-attach camera views with matrix computation.


• Hierarchy Transformation: Establish and compute 3D object heirarchy to reposition parts from their local space to world space.
  

Real-Time 3D Animation Technology

• I've learned and implement several different kinds of real-time 3D animation techniques. Here is the gist of it:
  Vertex Morphing - Stores key frames and use interpolation to animate the vertexes. Memory intensive but light on the CPU.
• Articulated - Individual animated parts are modeled as individual meshes, and bones and joints are used to animate the meshes. Less memory needed, but the joints are blocky because the joints don't share vertexes.
• Skinning (Rigid) - Similar to articulated, but each vertex is associated instead of at per-mesh level. Needs minimal memory, but requires more CPU power. The major draw back is that deformities can happen at the joints when animating.


• Skinning (Smooth) - A vertex can be associated with multiple bones with different weight values, this reduces the deformities at the joints but at the cost of more CPU computations.

A.I. - Autonomous Agent - Ants Simulation

This is my research project for my A.I. class. The program simulates a colony of ants attempting to find a food source via collective intelligence.

These ants emit trace signals that other ants will follow. Once the ants find the food source, the ants follows the trails back to the nest. As the number of ants traveling along the same trail increases, so does the amount of signals, which in term causes more ants to go along the same path.

In essense, these autonomous agents follow 3 simple rules for their actions:

1. Follow trace signal attempting to find food sources.
2. Return to nest when food is found.
3. Tell other lost ants the general directions of either "food" or "nest."

These "antbots" can only perform simple actions based limited environmental factors, but together as a colony they are able to find food sources quite efficiently.

Highlights:

• Autonomous agent system.

Code Optimization Techniques

Several common techniques that I've learned in my Optimization class:

• Instancing: static (pack geometries into the same vertex buffer), dynamic (similar to static, but transformed per frame), Shader (use vertex constants and GPU transforms the data), Hardware (supported by GPU).
  
• Reduce draw calls: Since the process of transferring data to the GPU includes overhead, the concept of instancing is to pack more data into the same buffer to improve the performance.


• Data Dependencies: How to write the code in special ways for the CPU to trade memory for computational speed.


• Threading: Avoid deadlocks and other abnormalities.


• Memory allocation: Avoid "new" memory at all cost.


• Benchmark, bottleneck, and performance tuning.


• SIMD: Single Instruction Multiple Data.

OpenGL Rendering

This is my project written with C++ and OpenGL. The goal of this project is to create a real-time 3D playground scene. 3D models are exported into source code and loaded into vertex buffer. The river is an animated mesh which is able to reflect the bridge above, and pointsprite was used to render the grass on the playground.

Highlights:

• OpenGL API
• Vertex animation
• Reflection with Stencil Buffer
• Pointsprite Grass

Game - Super Star

Super Star is my game project which is designed towards casual and female audiences. In SuperStar, the player assumes the role of a record company manager, who has a limited amount of time to recruite new pop stars and make them shine in the entertainment industry.

The player will recruite the stars by playing the puzzle mini-games, where correct answers to the pop-culture trivia will impress them and allow the player to manage them. In addition, to make the stars more popular, the player will train them through singing and dancing mini-games which improve their popularity stats.

As the pop stars gain popularity, the player can then book small concerts for them. The ultimate goal of the player is to have the stars perform at the biggiest event in town - concert at the stadium.

Highlights:

• DirectX
• Sprite Animation
• Music and Rhythm mini-games.
• Puzzle mini-games.
• Collision and physics.

Game - Mystic Kingdom

Mystic Kingdom is a 2D side scrolling action shooter game that I made in 2 weeks for my class project. The player controls a girl who can attack the monsters with projectiles, and level-up items are dropped randomly when the monsters are defeated.

Sprite animation system is used to deliver the graphics for this game. The animation is scripted by XML files. Each level is defined by a XML file which control the appearance and monster spawning, and the monster A.I. is controlled by behavioral scripting to give them more organic look.

Highlights:

• DirectX API.
• Sprite Animation.
• Script-driven level and monster AI.
• Physics simulation.
• Collision detection.