Hey yaya,

@yaya said in GetMg() returns not the actual coordinates:

Hey @ferdinand ,
My problem is: when I do this:
const Vector p = cube->GetMg() * Vector(-10, floatrandom(-2, 2), floatrandom(-2, 2));
I get the point shifted by -10 units by X-axis but by parent's X-axis. But I need it in the cube's X-axis.
Is it expected behavior for Cinema 4D?

No, this is not the expected behavior, and I can say with near 100% certainty that this is also not what will happen (there could always be some very fringe bug, but for something as fundamental as matrices, it is very unlikely).

You are likely making a mistake in another area of your code or in the scene files you use. My example also shows this exact operation, and it works there. This a very straight forward operation, my suspicion would also be that you still misunderstand something, either what global and local means, or more generally how linear transforms work. If you think there is a bug, you can easily test this on a sheet of paper or by pointing out that a frame or offset of a global or local matrix is not what it should be. But I would be surprised if you were able to do that.

I am making the plugin which creates the ragdoll from a user's character ...

I would recommend that you share executable code with us, either here or via e-mail if you are unable to share code publicly. See the Forum Guidelines: Confidential Data for details on the process. I was probably a bit unclear on what I meant with context, but what I meant is why your RayPosX

Matrix RayPosX = cube->GetMg() * shiftX; // !!! I don`t understand why this shifts the ray along the parent space (X-axis), but not the Cube's X-axis which might not match?

is matrix and not a point, as it would be more logical, as it would be more logical from its name and intended purpose. When you have some object obj, and you want to construct a ray with the ray direction rd of the global x-axis of obj from a ray origin ro, the (pseudo) code would be:

// As global points. const Matrix mg = obj->GetMg(); const Vector ro = mg * Vector(200, 0, 0); // The ray starts at (200, 0, 0) in the coordinate system of #obj const Vector rd = mg.v1 // For the ray direction we can reuse here just the x-axis of the object

I would also point out that GeRayCollider does operate in point coordinates, i.e., local coordinates, of the object which is being ray-casted. At least to me it is not clear if you are doing that. So, when you have an object cube, and you want to ray-cast from ro, which is at (200, 0, 0) within the coordinate system of cube, into the direction rd, which happens to be equal to the x/v1/i-component of the cube frame, intersection-testing the object target, then you must convert both ro and rd into the coordinate system of target. E.g., something like this:

const Vector roGlobal = mgCube * Vector(200, 0, 0); const Vector rdGlobal = mgCube.v1 const Vector roLocalTarget = ~mgTarget * ro; const Vector rdLocalTarget = ~mgTarget * rd;

PS: I am on vacation now, so someone else will take over this thread.

Cheers,
Ferdinand

How about updating ResEdit..?