Hi Ill try and explain what I’m trying to do.

Basically I have a custom modal that I have built. The modal has a position and rotation.

Each modal has a collection of parts. Each part has its own position and rotation and contains all the vertexs.

So to move the modal I have

```
matrix = Matrix.CreateFromYawPitchRoll(_parent.Yaw, _parent.Pitch, 0f);
matrix *= Matrix.CreateWorld(_parent.Position, Vector3.Forward, Vector3.Up);
```

Where _parent is the actual modal.

Then for each part I have

```
matrixpart = Matrix.CreateFromYawPitchRoll(part.Yaw, part.Pitch, 0f);
matrixpart *= Matrix.CreateWorld(part.Pos, Vector3.Forward, Vector3.Up);
```

My question is this Is there a way to combine these two matrixs? or would I have to do something like this

```
matrix = Matrix.CreateFromYawPitchRoll(_parent.Yaw + part.Yaw, _parent.Pitch + part.Pitch, 0f);
matrix *= Matrix.CreateWorld(_parent.Position + part.Position, Vector3.Forward, Vector3.Up);
```

Thanks for the help Matt