What does influence the performance (eg. for games)

Hello,

I am curious what does slow down the performance in blender regarding textures and materials. Mostly, I want to know what does slow down games.

My knowledge so far:

  1. Use always textures with the power of two: “8”, “16”, “32”, “64”, “128”, “256”, “512”, “1024”, “2048”

  2. Alpha uses two times more memory than normal images

  3. Unused texture-space is wasting memory as well

What I don’t know so far:

Do multiple materials for one object decrease the speed significantly? (material panel)
Do multiple uv-layouts decrease the speed significantly? (object data panel)
Do multiple textures decrease the speed significantly? (texture panel)
What about normal, spec and ambient occlusion maps? Are they using a lot of memory?

Hope someone can help me clarifying these doubts!

Thanks André

Did you see any impact on your fps when you tested these different scenarios out yourself ?

yes, i did change all my textures to game-format textures. that seemed to improve the frame-rate.
on the other hand, when using normal maps it seems to decrease the frame-rate.
About multiple materials, uv-layouts and textures I am not sure. I rarely use multiple materials.
Alpha textures (for example for particle effects) seem to decrease the frame-rate a lot!

Sorry about the weird format, for some reason all the line breaks dissappear whenever I hit “Preview Post”. In fact, the whole text editor is really messed up for me right now. 2. Alpha uses two times more memory than normal images I don’t think this is true, the alpha channel usually takes up only as much memory as one of the 3 main RGB channels. What I don’t know so far: Do multiple materials for one object decrease the speed significantly? (material panel) If you don’t go crazy with it, then it probably won’t have much effect on performance. However, using multiple materials as input into a shader nodes material can be slow. Do multiple uv-layouts decrease the speed significantly? (object data panel) I really don’t know for sure, but I imagine that the drop in performance would be small. Do multiple textures decrease the speed significantly? (texture panel) They can, for sure. What about normal, spec and ambient occlusion maps? Are they using a lot of memory? Spec and AO maps are usually grayscale, so they probably don’t use as much memory as an RGB image. Normal maps are usually stored in RGB format. But adding any additional textures can slow down a game.