Merge pull request #67 from bytestring-net/dev

Worldspace UI docs

.vscode/tasks.json

@@ -14,7 +14,7 @@
 		{
 			"type": "cargo",
 			"command": "run",
-			"args": ["--bin", "mesh2d"],
+			"args": ["--bin", "worldspace"],
 			"problemMatcher": [
 				"$rustc"
 			],

docs/src/SUMMARY.md

@@ -25,7 +25,7 @@
 - [Animation](advanced/animation.md)
 - [2D & 3D](advanced/2d_and_3d.md)
 - [Worldspace UI](advanced/worldspace_ui.md)
-- [Custom rendering](advanced/rendering.md)
+- [Custom rendering]()
 
 -----------
 

docs/src/advanced/worldspace_ui.md

@@ -1,5 +1,30 @@
 # Worldspace UI
 
-For now you can look at [worldspace example](https://github.com/bytestring-net/bevy_lunex/tree/main/examples/worldspace) on GitHub.
+Lunex in its entirety is built in worldspace.
+This means every UI element is bound to a place in the game world.
+
+You don't realize that, because when we are making a 2D game UI, we attach our UI to the Camera.
+
+If we wish for our UI to be spawned at fixed place in the world, then just spawn it as normal entity.
+This can be usefull for example if you want to create in-game displays, holograms and such.
+
+![worldspace](../images/worldspace.png)
+
+### Images
+
+For 3D images, you can take a look at this example: [worldspace example](https://github.com/bytestring-net/bevy_lunex/tree/main/examples/worldspace). You can use the built-in abstraction which just hides the fact that all what we are really doing is creating a material with our texture and then attaching it onto a plane.
+
+### Text
+
+3D text is currently limited and you have to use a 3rd party crate `bevy_mod_billboard`. You can take a look at how integrate it here: [worldspace text example](https://github.com/bytestring-net/bevy_lunex/tree/main/examples/worldspace_text)
+
+### Important
+
+When we are spawning a 3D hologram, we don't want the size to be the size of our camera, but some custom fixed size.
+You can achieve that by specifying the size in the `Dimension` component on `UiTreeBundle` when we are spawning our tree.
+If you don't do that, your UI size will default to 0 and you won't see anything if you use `Rl` units.
+
+Another fact to consider is `abs_scale`. If you use `UiTree::new2d`, then the abs_scale is 1. But if you use `UiTree::new3d` then the abs_scale becoms `0.001`. This is to create a sensible balance between sizes when going from 2d to 3d.
+
+Reason for that is, that in 2D Bevy, `1.0` in `Transform` corresponds to 1 pixel on screen. But in 3D Bevy, `1.0` means `1 meter`. You can now see the problem. To make things easier to use, I decided that when you are working with 3D UI in Lunex, all `Ab` units are in **`centimeters`**.
 
-*Coming soon...*