CrossSection

So this doesnt actually cut any geometry like a runtime boolean, this is all shader trickery? Thats so cool!

Will that then, work on much larger architectural models with many thousand objects, for example an entire airport that has exterior and interior?

Please tell me that if its shader, it is some kind of global override, and I dont have to go in my project and change every single existing material applied to those thousands of objects.......

 

There is a setup editor script, listing all the shaders on a given gameobject, where you can set shader substitutes. Then it generates material substitutes.
Then the cross section properties are driver by global shader variable.
So when moving the section plane you have to update the global shader properties.
(I am not sure if I tested it with HDRP).

 

I am using the CrossSectionBox in an AR project and the game objects in my scene consist of multiple materials within the same mesh render component. The first material is a wireframe material, which is a Unity asset called (Vacuum Shaders), and the rest are Cutout and Transparent materials (Clipping/Box/Autodesk Interactive). The project is running just fine, except if there are gameobject outside the section box, they are not rendered correctly. Once I remove the wireframe material, the problem is resolved.

Is there a way to resolve this issue.



Thank you

 

If you could send me the project or its minimal version I could take a look. Difficult to tell without seeing the project, I am also missing this wireframe asset.
The cross-section asset works only with a limited set of shaders.
You can also try to use - instead this wireframe shader - the outline effect which is already included into the asset.


If you like to get an effect like that:

With object inside box clipped and capped; and you want them visible together with their wireframes uncut - use a modified version of VR/SpatialMapping/Wireframe shader. Just one line of the "VR/SpatialMapping/Wireframe" shader needs to get modified.

Code (CSharp):

1. ...........
2.          fixed4 frag(g2f i) : SV_Target
3.         {
4.             float minDistanceToEdge = min(i.dist[0], min(i.dist[1], i.dist[2])) * i.dist[3];
5.         // Early out if we know we are not on a line segment.
6.         if (minDistanceToEdge > 0.9)
7.         {
8.             //return fixed4(0,0,0,0); //remove or comment
9.             discard; // add this line
10.         }
11. ...........

You need to create VR/SpatialMapping/Wireframe material and put it on the top of materials inside the box.

 

Hi,
Someone managed to modify shader to have more than one box-capped object on a scene? I have single mesh on scene and I want to cropp it in a few places.

 

You can create a new global shader keyword like CLIP_BOXES and add it inside the individual shader files to the existing keywords like CLIP_BOX, CLIP_SPHERE, CLIP_SPHERES ... and so on.

Then, inside inside the included section_clipping_CS.cginc file, you should declare new variables and new code for CLIP_BOXES.

While for the single CLIP_BOX you have single variables:

• uniform float4x4 _WorldToBoxMatrix;
• uniform float4 _SectionScale;

- for multiple CLIP_BOXES you should declare arrays:

• uniform float4x4 _WorldToBoxMatrixes[n]; //where n is maximum box count expected
  
• uniform float4 _SectionScales[n]; //where n is maximum box count expected
• uniform int _boxCount; //actual count of boxes to loop through in the shader code

Then go to the function

Clip(float3 posWorld)

(or

PlaneClip(float3 posWorld)

- it can be differently named depending on asset version), where you find the code for CLIP_BOX

Code (CSharp):

1.         #if CLIP_BOX
2.         bool _clipBox = clipBox(posWorld, _WorldToBoxMatrix, 0.5*_SectionScale.xyz);
3.         _clip = _clip || _clipBox;
4.         #endif

For CLIP_BOXES you have to duplicate this code and place it inside loop:

Code (CSharp):

1.         #if CLIP_BOXES
2.         bool _clipBoxes = false;
3.         int _centerBoxesTruncated = min(_centerCount, 64);//let's assume 64 as maximum box count expected
4.         for (int i = 0; i < _centerBoxesTruncated; i++)
5.         {
6.             _clipBoxes = _clipBoxes || !clipBox(posWorld, _WorldToBoxMatrixes[i], 0.5*_SectionScales[i].xyz);
7.         }
8.        _clip = _clip || !_clipBoxes;
9.         #endif

This is analogical like code for CLIP_SPHERE and CLIP_SPHERES.

If you need your boxes display caps properly, you should also make an analogical addition to the

ClipWithCaps(float3 posWorld)

function code.

 

Hello,I'm a rookie。I want to know how to create a cylinder clipping?I didn't find it in the assets。
And I want to know how to replace the material of the cross section。

 

You can find the multi_tube scene example in the asset.
You can use the materials from that scene.
In this example the cylinder axes get aligned to ray from camera, then you set cylinder radius by dragging on the screen. This is being done in the MultipleTubesExample.cs script. Set cylinder axes and radii your own way, according to your needs.
This is a multiple cylinder example, if you need single cylinder only, set the array sizes to 1.
If you like to use other cross-section shaders, check whether this line:

Code (CSharp):

1. #pragma multi_compile __ CLIP_PLANE CLIP_TWO_PLANES CLIP_SPHERE CLIP_CUBE CLIP_TUBES CLIP_BOX

contains the CLIP_TUBES keyword and add it if it does not.
I place most common keywords only into the shaders inside the package, because they bloats the asset size and extend the build time.

 

thanks。i find the multi_tube scene example，But I want the opposite effect。Show inside cylinder, hide outside cylinder。

 

Check the inverse checkboxes on the shaders and you are done.

 

i get,thanks.

 

I'm using this asset to make sections of buildings in AR, using URP. In Unity editor and on Android everything works fine, but on iOS the CrossSectionURP shaders don't get rendered. The shadows are visible though, so there is something there. Anyone know what is going on here?

The first picture shows an Android screenshot (the way it should be), and the second shows a screenshot from iOS.

 

And the shadows seem to get cut properly.
Which Unity and asset version is it?
Try to use some different shader.
Unfortunately I haven't got Mac, so I can only take a look at it in Unity Editor, instead of fully testing the builds.

 

Unity version: 2020.3.13
crossSection version: 2.81

I tried to select a different shader, but the entire CrossSectionURP menu is gone. So I took a closer look at the shaders in the crossSection (URP) > shaders folder and all of the shaders have error messages.
They are all like this:

Shader error in 'CrossSectionURP/LitAndCapPrepare': Couldn't open include file 'Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl'. at Assets/WorldSpaceTransitions/crossSection (URP)/shaders/LitInput.hlsl(3)

I only get these errors on my mac and not my windows. Really weird. But I guess that's the reason why they won't render on iOS, because they won't compile.

I checked my URP package, which is up to date. I also tried deleting and reimporting the crossSection asset, but same errors show up. Perhaps tomorrow I could try with a fresh Unity project.

Edit: What's also weird is that the shader still works in the editor, even though it has errors and I can't select it anymore from the shader dropdown.

 

When using one plane - the space is divided into two regions. If two - there will be three regions if the planes are paralell or four regions, like in the pie section scene inside the asset.
Generally the number of spaces equals to

according to https://mathworld.wolfram.com/SpaceDivisionbyPlanes.html - and you should decide which regions to crop and which to keep.

If you like to skip this space divisions considerations, setup a new keyword _CLIP_PLANES, setup arrays for it and so on - analogically like in the above post here which relates to multiple boxes and analogically to code for multiple spheres or multiple tubes, which is included inside the asset.

If you like to I rotate one single side of CubeSection, generally you have to code each of the 6 planes independently.
The code for cube section supports non-uniform scale, so if you like to rotate one single side in some limited range of angles only, you can also try make a superposition like that:



- discarding the content which is both inside the cube and behind the plane.

 

I was able to get rid of the errors I mentioned earlier by deleting library folder and reopening Unity, but that didn't do anything for the issue unfortunately.

I then tried using the shadergraph shaders on iOS, which almost worked! The section is correctly displayed, but the AR camera background starts jittering like crazy.

Another problem is that the shadergraph shaders become black on Android. When I build the box_capped_advanced_urp scene to Android, this is the result:

The same thing happens with the single_plane_cap_urpgraph. From the example scenes it becomes clear that all of the shaders in the CrossSectionGraph folder have this problem on Android.

Did this work correctly when you tested it @tomekkie2 ?

 

I have usually kept on testing the Android, WebGL builds for builtin and urp and standalone build for HDRP.
I might also assume some changes as not considerable enough and skip some testing.
I am just making a build and will try that on the Samsung phone.
A will check it all now and let you know.
Thank for reporting this.

 

Thank you for checking it out!
I've done a few more tests on iOS and seems that the CrossSectionURP/Lit and /SimpleLit work pretty well, but causes the same jittering in the AR camera background, as well as a delay in updating AR position.

 

I tested it on the Samsung Galaxy S8 phone and it works.
Here are my screenshots from the urp shadergraph scenes you have mentioned.


The Unity version I have tested is Unity 2020.2.2f1, and URP 10.2.2, the same which I have used to upload the latest version to the AssetStore.
I am also going to test is with a 2021.x.x., to check whether the compatibility might get broken somewhere in-between these versions.
Does the AR background jittering happen on shadergraphs only, or on all shaders, on IOS only or on Android as well?
Just trying to guess - possibly it might have something to do with use of stencils and URP Render Objects?

 

It could be the Unity version then. Wouldn't be the first time Unity broke something with a new version. I will test it on 2021.x.x when I have the time.
The AR background jitter only happens on iOS. So far I've tested the urp shadergraph, urp lit and urp simple lit, which all have that jitter when I test it. Perhaps upgrading to 2021.x.x would also solve that as well.

 

I have tested in 2021.1.3f1 and these demo scenes also work the same properly there.
Maybe it is the AR subsystem like Arkit or Arcore or Vuforia that could cause some conflicts.

 

Hi, I have a problem when setup the HDRP project, import crossSection plugin and load "crossSection (HDRP)" package. I'm using Unity 2019.3, I've tried it on 2020.

 

This will not work in Unity 2019.3.
The hdrp sub-asset works since 2020.1.0. with High Definition and Shader Graph package v. 8.2.2.
Unity 2019.3. uses High Definition and Shader Graph package v. 7.3.1
Getting he hdrp sub-asset to work with 2019.3 would require adapting it to High Definition package v. 7.3.1. Possibly the shader graphs from urp package woud work.

 

@tomekkie2 I've tried it again but with Unity 2020.1.0. with High Definition and Shader Graph package v. 8.2.0. It doesn't work.

 

What materials are shown on these pink objects in inspector?
You were saying abot the "crossSection (HDRP)" package, possibly you are missing the other one: "crossSection (URP&HDRP)", which contains shader graphs and materials.

 

@tomekkie2 I've tried it again: create HDRP project in Unity 2020.1.0f1, import cross section package from my assets, import "crossSection (HDRP)" or "crossSection (URP&HDRP)" or both, "open box_capped_advanced_hdrp" scene, the result is the same.
Do I miss something?

 

I have checked this and - unfortunately - I am getting the same. I do apologize for all the inconveniences. I have the asset project in 2020.1.0f1 where these scenes are working and I am currently checking what has gone wrong. Thank you for letting me know. I am hoping to export these packages from the working project again, check them and send them to you and then update this asset version on the store.
_________________________________________________________________________
Update
I have re-uploaded the package for 2020.1.0f1 with fresh hdrp unity-packages.

 

The best is to use cube section.
In the most recent version I have changed the shader code replacing the _Radius float with _SectionScale Vector3 variable.
Capped cube (or inside box or box hole) section is cheaper, because the stencil and visible material areas are the same, so they are drawn in single pass, while box section requires two passes.

 

Yes, correct.
The newest one will be 2.83 soon, but only the second last package, from Unity 2020.1.0. will be updated (because of hdrp problems reported in posts above); the last package, from Unity 2020.2.2 stays the same.

 

I have a feeling I have messed it all up and should make some revision.
I think the _inverse toggle doesn't always make sense in case of capped setups, where additional stencil pass is used.
I would just remove the _inverse toggle (I did it in the last version) from the box section shader, because it has this additional stencil pass.
The _inverse toggle makes sense when no caps and no stencils are used, e.g. in case we need to divide the space into two complementary subspaces and then apply two separate materials to them; one with the _inverse toggle on and other with the _inverse toggle off.
I would rename - because of non uniform scale - the cube section (because cube is supposed to be regular) to box-hole or rect-hole section allowing the _inverse toggle on it.

 

Hello, I saw that there is an example of MultiBoxExampleController, but I didn't find any scene that contains it. This CLIP_BOXES would be to handle an array of CLIP_BOX?

 

Handling array is not difficult, but it is not possible to handle caps, maybe some special cases only, I have tried and gave up.

 

What is the name of the scene in this example? I couldnt find it here.

 

Regarding the Built in shaders - it is dependent on Post Processing Stack V2 and is hidden inside the unitypackage.
You have to istall the Post Processing Stack V2 using Package Manager, and then unpack EdgeEffect(Post Processing).unitypackage, according to the instructions here:
https://virtualplayground.d2.pl/wiki/Manual#Instalation
The scene you are asking is inside package.

Regarding the URP shaders it doesn't require any optional packages and it is a matter od pipeline asset used in the scene. The example scene coud be single_plane_outl_urp.

 

Ok, thanks tomekkie2

 

Hi tomekkie2, I've test in Unity 2021.2.0b12 with URP 12.0.0 and got some errors. I think had removed/changed some methods and vars you can't use for now, and maybe you need make a #if for this URP version. I fixed some issues, others only commented, but its better you can take a look.

 

The current version is based on Unity 2020.2.2, URP 10.2.2 and HDRP 10.2.2, so that means it is a time to update.

In Unity 2021.1.x and URP 11.0.0 everything seems to work.
In Unity 2021.1.x and HDRP 11.0.0 I had to make some small corrections to get it to work, so I guess I should also make update for HDRP 11.0.0.

 

Hello tommekkie2, thanks for check.

The version I've test is a beta version (Unity 2021.2.0b) which force uses URP 12.0.0.
if you are not interested in updating, let me know, but I think it would be good too.

 

I am just not sure if I can make a beta version of the asset and update it from Unity beta to the AssetStore. Is that possible?

 

I don't know either, then I think it's better to talk with Unity support.
But maybe using something like #define, you can use both versions.

 

Good afternoon. Thank you for asset. I have problem with edge effect. When I use camera control from asset and rotate camera i see good effect of edge highlight, but if i rotate camera without control, just using transform, in other angles of rotation, highlight of intersection sometimes disappear. How can i fix that or what i do incorrect?

 

I'm working with the 2021.2.0f1 release (now out of beta), which uses URP 12.0.0, and there are many errors showing in the URP scenes that I'm trying to use and they won't start for me. If you get chance to post an updated version to the Asset Store, that would be great. I'm keen to get started with you amazing looking cross section asset.

 

Apologies for answering that late, but I am just checking the HDRP and URP after updating to Unity 2021.2 and HDRP/URP 12.0.0. I have already finished with HDRP. Below I am testing whether SSAO (screen space ambient occlusion) is working well with cross-section staders and selective outline effect in the asset.

Once I am done I will upload the update to the AssetStore.

 

Can this asset be used if I only want a section through SOME objects? and can the section be animated by script?

For example if my roof is 1 object, and my walls are another object, I want to cut the roof in 1 direction via script, and after that, follow with the walls from a different direction.

 

Yes, it can be used.
The asset contains several demo scenes, possibly some may fit your scenario.
Take a look at the webgl demo and go to the corner section scene with 3 perpendicular planes or to the box section scene with six perpendicular planes or to the pie section scene with two planes.
You can also see the [animated gifs] from the two first of these scenes here.
In the corner and box scenes the planes can be manipulated with mouse in the playmode.
In the pie section one plane can be manipulated with mouse, while the other is animated by script.