@s4real, that makes a lot of sense.
Quote: "Things to remember if you add another light once the characters have been added it will rebuild the lightmapping again so make sure you have your lights where you want them before adding your dynamic stuff."
Also, placing new segments or static enity's will force it to rebuild.
Quote: "I did have an idea of creating an entire game from one texture, thinking it would save a lot of resources.
I would be interested to know how much memory is actually saved from using Atlas Textures?"
Atlas saves on memory GPU calls as textures are loaded and unloaded during game. There are some things to bear in mind when using these in FPSC.
It's not worthwhile unless using completely custom media and planning it all out from the start, or your looking at uvw mapping all media you do use (you will be looking at doing this for all shader maps too and unless all objects use a shader of some sort then that space is wasted.
FPSC uses more than one diffuse texture for segments which are selected randomly to prevent too much repetition. You have no way to randomly select them without putting these into an Atlas too and selecting them as individual segments. In other words you will have 3-4 meshes to uv map and 3-4 fps files to create and 3-4 individual segments to place randomly by hand just to get the same result.
If you only have one model in scene which uses a particular Atlas sheet then all the other space on that texture is a waste of memory. Same goes for shader maps such as illumination which not all objects will require, since the object uv's will be placed on the shader texture sprite sheet same as the diffuse your going to have a lot of unused space on these.
Since it looks like only entity's would be worth the time and effort using these then it would be important to ensure they are always used, I reckon that FPSC would drop a whole Atlas texture if none of these entity's were in view but it would certainly be a waste of memory if only one were in view and the whole Atlas is loaded. I am not up on the code so cant say exactly how it loads and unloads textures and to be honest don't have the inclination to sit testing memory consumption to see how it does with it all. Maybe someone else has looked into it and can give some definite figures.
Of course if your not going to use shaders on any of your objects and if your sure your going to use all textures on a sprite sheet throughout the level of your game then go for it and see what results you have, but for the reasons above I dropped any sort of idea of using these in any major way in FPSC, and don't see many first or third person PC games these days which do use them (maybe back when GPU cards didn't have the memory they do now, Doom comes to mind and characters were....well...sprites). Mostly they seem to be used nowadays for mobile app games.
DX9 limit is 4096x4096.
A dds 2048x2048 texture is 2.66Mb. A dds 512x512 is 170kb, making sixteen of these 2.72Mb. A 7% file size difference for textures doesn't seem worth the extra effort when it comes to build file size. It would need to be a huge saving on GPU in game to make it worthwhile and, for me at least, to think of all that extra uv work.
Sure using the same texture on multiple objects makes sense but putting ALL textures for multiple use into an Atlas only makes sense if using all textures on that sheet in a scene and it has a
major impact on GPU memory usage.
