Maya python 适合相机视图到网格

Question

I want to fit a camera-view to a mesh from a fixed point. See attached image.

Example

So I need to adjust the camera rotation, focal length and frame width/height.
What is the best way to do this with python?

Answer 1

What you're asking is relatively complex in terms of operation. You're adjusting multiple camera properties to frame an object.

I recommend you decompose the problem into parts and ignore focal length all together. Simply transform a camera so it frames the object. You can then add a supplementary step to modify the width and height of the camera to tightly frame it.

The gist of what you want to do is as follows:

• get bounding box of object
• get camera aspect ratio
• get active viewport representation
• get camera matrix based on object bounding box and corresponding camera aspect ratio mapped from active viewport
• apply matrix to camera

This will be much easier if you're familiar with the OpenMaya API. The OpenMayaUI.M3dView and the OpenMaya.MFnCamera classes should get you started.

https://help.autodesk.com/view/MAYAUL/2019/ENU/?guid=__py_ref_class_open_maya_u_i_1_1_m3d_view_html

https://help.autodesk.com/view/MAYAUL/2019/ENU/?guid=__py_ref_class_open_maya_1_1_m_fn_camera_html

If you're unfamiliar with the API, then scour the mel scripts and check how the FrameSelectedWithoutChildren Runtime Command (F key in the viewport) shortcut works, and use that to automate the process.