A Particle System

By: Joseph Moyle

Controls:

Esc – Exit.
Shift – Toggle particle’s geometry.
Backspace – Toggle between controlled camera/emitter.
Arrow Keys – Move camera/emitter.

Updates:

Goals
- To create a solid and robust system, that is both simple to use and easy to customize.
- To polish the project and make it as difficult to misuse as possible.
- To remove unnecessary expansions that I had introduced last sprint.
Changes & Additions
- sVector input force, which gives them a constant force that is applied to all particles upon creation.
- Removed the variable length of the transforms array.
  - Users now have a fixed number of particles.
  - Particles are created upon spawn, and are reset rather than destroyed and created.
  - A particular particle will always be contained as the same element in an array.
    - You can use these elements as implicit identifiers.
- Converged back into one cEmitter class.
  - Functionalities from other emitters can simply be created with a singular point emitter.
- cEmitter‘s body is a sRigidBodyState which you can now move around.
  - This will effect the spawning position of refreshed particles, not where the currently are now.
- EffectBuilder project is completed.
  - You can now load many different cEmitters into your game.
    - This functions similarly to how we have created other systems up until this point.
    - Specifying any field is entirely optional.
      - Default values can be set in the cEmitterBuilder.cpp.
- How I Did It.
  - By following the same process we have used for both our cGeometry and cEffect assignments, I was able to create the builder project and binary reading load function in a timely manner.
    - This allowed me to focus on the functionality more.
    - I decided to unify my many sRigidBodyStates update functions into one per emitter.
    - This allows the game play programmer to lessen the amount of code they have to use.
  - By restricting the public accessible variables, I removed a lot of room for error.
  - Keeping the transforms array as a public facing data retrieval made it easy to keep things safe.
- What I Learned
  - I should have put in more time thinking about how I could customize the inputs of an emitter.
  - Finishing one initial emitter first then moving on would have been a better move, rather than attempting to add functionality before I considered everything I might have to do.
  - How to more efficiently write to a binary file.
    - I didn’t fully grasp how to utilize this previously.
  - Design first.

Adding the System:

*Particles* Project to put in your *Engine* Directory

*EmitterBuilder* Project to put in your *Tools* Directory

*EmitterBuilder* Project Property Sheets

Insert These:

What to add to your *AssetBuildFunctions.lua*

Example Uses:

A Demonstrative Struct to hold your *cEmitter*

Hot Tip: Do not call update on the emitter.body, as this is done within emitter.Update. You may, however, use the emitter.body to render something at the source if you wish.