Bug. Impossible to save named view with perspective camera. Resulting camera has very different eye.

[soswow]

Here is the simplest code:

#Author-
#Description-

import adsk.core, adsk.fusion, adsk.cam, traceback
import math
from adsk.core import *
from adsk.fusion import *

def run(context):
    ui = None
    try:
        app = adsk.core.Application.get()
        ui = app.userInterface

        design = Design.cast(app.activeProduct)
        camera = app.activeViewport.camera
        camera.perspectiveAngle = math.radians(35)

        design.namedViews.add(camera)

    except:
        if ui:
            ui.messageBox('Failed:\n{}'.format(traceback.format_exc()))

When I execute this, it creates named view for the current camera position and orientation. But when I click on that view it moves far away from where camera was/is.

So it that was the original position when script is ran:

then after clicking on saved named view it goes way back:

Did some debugging and logging.

# Example of current camera when saving as named view:

current camera details. eye: x: 209.2645 mm, y: -27.2470 mm, z: 97.5599 mm target: x: -8.3656 mm, y: -10.8403 mm, z: 15.7369 mm up_vector: x: -2.7197 mm, y: 4.9824 mm, z: 8.2328 mm

# CAmera that is attached to saved named view
saved view camera details. eye: x: 3442.8070 mm, y: -271.0171 mm, z: 1313.2829 mm target: x: -8.3656 mm, y: -10.8403 mm, z: 15.7369 mm up_vector: x: -2.7197 mm, y: 4.9824 mm, z: 8.2328 mm

Even if I construct camera myself from scratch:

camera = app.activeViewport.camera

        new_camera = Camera.create()
        new_camera.cameraType = CameraTypes.PerspectiveCameraType
        new_camera.perspectiveAngle = math.radians(40)

        new_camera.isFitView = False
        new_camera.isSmoothTransition = True
        new_camera.eye = camera.eye.copy()
        new_camera.target = camera.target.copy()
        new_camera.upVector = camera.upVector.copy()
        
        app.activeViewport.camera = new_camera
        
        design.namedViews.add(new_camera)

It would still stores much farther camera

[soswow]

Still haven't found a workaround. Except for maybe creating it manually in UI which is not what I incision as a workflow for my plugin..

[soswow]

It's something to do with it being perspective ... 

Look at this:

import adsk.core, adsk.fusion, adsk.cam, traceback
import math
from adsk.core import *
from adsk.fusion import *

def run():
    ui = None
    try:
        app = adsk.core.Application.get()
        ui = app.userInterface

        design = Design.cast(app.activeProduct)
        
        while design.namedViews.count > 0:
            design.namedViews.item(0).deleteMe()
        
        for i in range(10):
            fov = 20 + i * 5
            new_camera = Camera.create()
            new_camera.cameraType = CameraTypes.PerspectiveCameraType
            new_camera.perspectiveAngle = math.radians(fov)
            new_camera.isFitView = False
            new_camera.isSmoothTransition = False
            new_camera.eye = Point3D.create(0, 0, 10)
            new_camera.target = Point3D.create(0, 0, 0)
            new_camera.upVector = Vector3D.create(0, 1, 0)
            
            new_named_view = design.namedViews.add(new_camera)
            app.log(f'fov: {fov} with camera.eye.z == 10 named view cameras becomes {new_named_view.camera.eye.z}')

    except:
        if ui:
            ui.messageBox('Failed:\n{}'.format(traceback.format_exc()))

This generates this:

 fov: 20 with camera.eye.z == 10 named view cameras becomes 8040.859369381589
 fov: 25 with camera.eye.z == 10 named view cameras becomes 5086.622801252298
 fov: 30 with camera.eye.z == 10 named view cameras becomes 3482.0508075688767
 fov: 35 with camera.eye.z == 10 named view cameras becomes 2514.7533975943365
 fov: 40 with camera.eye.z == 10 named view cameras becomes 1887.1580426032576
 fov: 45 with camera.eye.z == 10 named view cameras becomes 1457.1067811865469
 fov: 50 with camera.eye.z == 10 named view cameras becomes 1149.7274830283475
 fov: 55 with camera.eye.z == 10 named view cameras becomes 922.5430830356662
 fov: 60 with camera.eye.z == 10 named view cameras becomes 750.0000000000005
 fov: 65 with camera.eye.z == 10 named view cameras becomes 615.9782027526672

new z changes depending on camera's FOV

in this relationship:

[soswow]

I am more then sure it is a bug.

[kandennti]

@soswow -San.

I was curious so I tested it out to try a few things.

# Fusion360API Python script

import traceback
import adsk.core as core

def run(context):
    ui: core.UserInterface = None
    try:
        app: core.Application = core.Application.get()
        ui = app.userInterface

        vp: core.Viewport = app.activeViewport
        cam: core.Camera = vp.camera

        dumpCam(cam)

        cam.cameraType = core.CameraTypes.OrthographicCameraType
        vp.camera = cam
        dumpCam(cam)

        cam.cameraType = core.CameraTypes.PerspectiveCameraType
        vp.camera = cam # <-error
        dumpCam(cam)

    except:
        if ui:
            ui.messageBox('Failed:\n{}'.format(traceback.format_exc()))

def dumpCam(cam: core.Camera) -> None:
    dump("","")
    dump("type", cam.cameraType)
    dump("eye",cam.eye.asArray())
    dump("target",cam.target.asArray())
    dump("dist",cam.eye.distanceTo(cam.target))
    dump("perspectiveAngle",cam.perspectiveAngle)
    try:
        returnValue, width, height = cam.getExtents()
        dump(f"{returnValue}:{width}:{height}","")
    except:
        pass

def dump(msg, x) -> None:
    core.Application.get().log(f"{msg}:{x}")

I got an error when switching the camera to Perspective. (ver 2.0.20476)
This used to work before. There seems to be another bug here.

[MichaelT_123]

https://forums.autodesk.com/t5/fusion-api-and-scripts/camera-viewextents-property/m-p/12488088