Unified doc for rendering performance

docs/Modders/Images-and-Audio.md

@@ -18,20 +18,25 @@ If you're developing your mod on an Android version of Unciv (not recommended!)
 - You can use external tools, [e.g. gdx-texture-packer-gui](https://github.com/crashinvaders/gdx-texture-packer-gui). Utmost care needs to be taken that the files can be discovered by Unciv and internal relative paths are correct.
 - The Unciv repo itself has a feature that can pack images on github runners
 
-### Multiple texture atlases
+### Rendering performance
+
+#### Multiple texture atlases
 
 If your mod has lots of images (or large ones), the textures might 'spill' into additional texture files - 2048x2048 is the limit for a single texture pack. You will see a `game2.png`, possibly a `game3.png` or more appear.
 This is not good for performance, which is why the base game controls which kinds of images go together into one texture(+atlas).
 This works for mods, too: Create not only one Images folder, but several, the additional ones named "Images.xyz", where xyz will become the filename of the additional texture file (So don't use both Images and Images.game - those will clash). Look at the Unciv base game to get a better idea how that works.
 To minimize texture swaps, try to group them by the situation where in the game they are needed. You can distibute by folder, but having the same subfolders under several "Images.xyz" and distributing the images between them will also work.
 
+For an example, you can see the [Alpha Frontier mod](https://github.com/carriontrooper/Alpha-Frontier).
+
 A file `Atlases.json` (uppercase 'A') in the mod root (not in `Images` or in `jsons`) controls which atlases to load, which in turn control which texture (`.png`) files are read.
 This file is automatically created by the built-in packer. Only the `game.atlas` file is read by default for backward compatibility.
 If you use external tools and multiple atlases, you will need to maintain this file yourself - it is a simple json array of strings, each a file name without the `.atlas` extension (saved as UTF-8 without byte order mark).
 
-### Rendering Performance
 
-Images that are packed together are much faster to render together. If most of the images in your mod are using images from the mod, we want to be able to wrap them from images *also* from your mod.
+#### Circle icons
+
+If most of the images in your mod are using images from the mod, we want to be able to wrap them from images *also* from your mod.
 To allow for faster rendering for icons, which has a major performance effect, you can copy the ["OtherIcons/circle.png"](https://github.com/yairm210/Unciv/blob/master/android/Images.Icons/OtherIcons/Circle.png) to:
 
 - "ImprovementIcons/Circle.png" for improvements
@@ -40,6 +45,7 @@ To allow for faster rendering for icons, which has a major performance effect, y
 - "ConstructionIcons/Circle.png" for buildings and units
 - "StatIcons/Circle.png" for stats
 
+
 ### Texture packer settings
 
 The texture packers built into Unciv will look for a `TexturePacker.settings` file in each `Images` directory (_not_ under `jsons`).