what is video game optimisation and how does it get done well or badly?
In: 6
Optimization is a huge topic, and there are many parts to it. You also often need to optimize to target specific aspects, such as frame time, loading time, disk space, memory, or quality, given that its common that optimizing for one often comes at the expense of others. The process of optimizing is also commonly split across disciplines: an artist might produce inefficient work, a programmer might write code that is not efficient, or a designer may want to do something that just cannot be done efficiently.
Optimizing for frame time generally means either reducing the amount of work being done or doing that work more efficiently. Reducing the work includes having artists redo parts of their work to reduce its complexity. Its easy for an artist to get hyper fixated on a single task, forgetting that the character’s ring is going to be tiny on the screen – an optimization here would be to have the artist redo the ring to be simpler. Programmers might write their code to do the same calculation multiple times, when the result could instead be saved and reused. Designers might want to have a set of mirrors in a room, but reflections prove to be too expensive to render, requiring the room to be redesigned to have fewer, or no, mirrors.
Another major form of frame time optimization is to multi-thread the game, allowing multiple calculations to run at the same time. Such optimization is generally very complicated and comes with the risk of race conditions, where the order in which the calculations occur affects the result.
Optimizing for disk space generally means adjusting compression algorithms or removing duplication of data. Generally, such optimizations come at the cost of increasing loading time.
Optimizations for loading time generally involve arranging data on the disk to make it faster to load, or require less calculations to convert its format. Both are likely to result in the game taking more disk space.
Good optimization takes a lot of development time and is a very complex thing to pull off. Additionally, you can always keep optimizing a product, so you have to stop at some point when its “good enough”. Of course, “good enough” is extremely subjective.
There are also major complexities, especially when making a PC game, as what works well on one set of hardware may be worse on another, as well as what else the user might be doing at the same time may affect what optimizations are best. Consider if I have a really powerful graphics card (GPU), but a fairly weak CPU – moving work from the CPU to the GPU is probably a good idea. However, if you have a weak GPU but a powerful CPU, that same optimization may have a worse outcome for you.
Latest Answers