Immediate Contact Generation

Looks great! Here's some quick feedback:

Code (CSharp):

1. m_Shape = GetComponent<Collider>().GeometryHolder;
2. geom1[1] = GetComponent<Collider>().GeometryHolder;

Shouldn't be "geometryHolder", lowerCamelCase? In Unity API the property names begin with lower case, while method names begin with upper case. Otherwise, "GeometryHolder" is confusing as not only it's not a method, but also it's the type name. All other other properties in Collider follow the correct Unity API convention.

Code (CSharp):

1. // If we want to retrieve the BoxGeometry that is stored inside, we have to call the "As" method.
2. // This will only work if the GeometryHolder was created with the BoxGeometry first, otherwise,
3. // when you try to retrieve a different shape, it will throw an InvalidOperationException
4. m_BoxGeometry = m_Shape.As<BoxGeometry>();

I guess there would also be a method for retrieving the geometry type? So we can compare if the shape is a specific geometry type, something like this:

Code (CSharp):

1. Geometry geometry = m_Shape.GetGeometry();
2. if (geometry is BoxGeometry) Debug.Log("This is a box");

Which excites me most is:

Code (csharp):

1. using UnityEngine.LowLevelPhysics;

I assume it's not yet documented, as the docs for 2023.1 doesn't include it. I assume it's the placeholder for exposing more low level portions of PhysX

 

Also, what's the information provided in each contact (ImmediateContact)?

 

Hi Anthony, glad to see you're still around Good to know about the progress and future plans on the immediate mode.

Totally understood. I meant about the specific case of Collider.GeometryHolder, which is a property returning an object of type GeometryHolder. Nothing about the type itself, but as per my understanding the name of the property exposed in the Collider component should be geometryHolder, lowerCamelCase. Otherwise it would be contrary to the rest of the properties and methods exposed in Collider.

 

Thank you for the info. I've also seen other parts of Unity also adopting these new standards (Cinemachine 3.0). Do you guys have some guide or refer to some common resource across Unity as reference for the coding style to adopt? I'd just like to be ready to change my APIs as well when it's time to.

 

Cool, thank you! That guide is very useful.

 

First of all, thank you very much for bringing this great feature to Unity ... more immediate mode stuff please!

I've done a few tests combining all kind of geometries, and i think i've found a bug. The problem i'm experiencing is that Transform's rotation and ImmediateMode's Rotation don't match when the geometry involved is a capsule. I have tried with boxes, spheres, cylinders and other convex/non-convex geometries, and they all worked fine.

For example, when setting the immediate transforms like this:

Code (CSharp):

1. // Capsule geometry
2. immediateTransformsA[0] = new ImmediateTransform
3. {
4.        Position = transform.position,
5.        Rotation = transform.rotation
6. };
7.  
8. // Box geometry
9. immediateTransformsB[0] = new ImmediateTransform
10. {
11.        Position = TargetCollider.transform.position,
12.        Rotation = TargetCollider.transform.rotation
13.  };

This is what happens (red line represents the "contact penetration"):


... As shown here, the capsule geometry appears to be rotated to the left (z axis) 90 degrees.
Now, if i rotate the capsule geometry 90 degrees to the right:

Code (CSharp):

1. // Capsule geometry
2. immediateTransformsA[0] = new ImmediateTransform
3. {
4.        Position = transform.position,
5.        Rotation = geometriesA[0].Type == GeometryType.Capsule ? Quaternion.AngleAxis(90f, Vector3.forward) * transform.rotation : transform.rotation
6. };
7.  
8. // Box geometry
9. immediateTransformsB[0] = new ImmediateTransform
10. {
11.        Position = TargetCollider.transform.position,
12.        Rotation = geometriesB[0].Type == GeometryType.Capsule ? Quaternion.AngleAxis(90f, Vector3.forward) * TargetCollider.transform.rotation : TargetCollider.transform.rotation
13.  };

I'll report this