SketchUp and KeyShot FOV and Focal Length don't match

driven

@chippwalters said:

So then, what do I do next? Use the Keyshot plugin button to export the file? Will it use your script or it's script?

it will use the last loaded script, i.e. my version...

chippwalters

Thanks.

I did what you said, but the results weren't what was expected:

ORIGINAL in SU (Focal Lenght 42mm, FOV 46.8 degrees)
Using your plugin code. Note the FOV is different, but still not correct.
ORIGINAL KS Plugin. Note the FOV is also different.

driven

you want post the skp [or PM...]

chippwalters

Here's the SKP
https://dl.dropboxusercontent.com/u/3788438/3D/test.skp

driven

btw, so you know...

the only thing I change was a 'back up' for a SU shortfall

 if cam_aspect == 0.0
        cam_aspect = width/height.to_f.round(3)
      end

I you don't have a Advanced camera set, SU sets the aspect ratio to 0.0, which is crazy...
this bit of code just tell KS to use 16:9 in that circumstance...

I'll have a look at your skp...

chippwalters

@driven said:

btw, so you know...

the only thing I change was a 'back up' for a SU shortfall

 if cam_aspect == 0.0
>         cam_aspect = width/height.to_f.round(3)
>       end

I you don't have a Advanced camera set, SU sets the aspect ratio to 0.0, which is crazy...
this bit of code just tell KS to use 16:9 in that circumstance...

I'll have a look at your skp...

Thanks again for your generous help.

I did look at your Ruby and saw that, and was wondering if there was anything else. I've written some Python scripts for Vue-Infinite, but don't know much about SU's api-- other than other plugins have figured this out-- and KS hasn't. I believe they first mentioned to me SU didn't have the correct api hooks to get an accurate camera from. That's when I mentioned all the other renderers have figured it out. They said they would take a look at it. Last time they said they'd work on the SU plugin it took them 2 years.

Too bad Thea and Vray are so damn slow compared to Keyshot. Of course, they both can do a lot more too!

Fwiw, here's an interior shot modeled in SU, and rendered in KS @ 1920x1080. Took a bit under 3 hours on my 2013 i7 iMac. Anyone think Thea can do that? If so, I have a license and can try. My early tests told me no, but then I'm not an accomplished Thea user.

driven

that looks very well accomplished to me...

I think KS may ignore the 0.0, even though they extract it...
heres some code that I've been fiddling with to try and work out the variance...

      model = Sketchup.active_model
      camera = model.active_view.camera
      position = camera.eye.to_a
      direction = camera.eye.vector_to(camera.target)
      up = camera.up
      fov = camera.fov
      aspect_ratio = camera.aspect_ratio
      width = model.active_view.vpwidth
      height = model.active_view.vpheight
    
     p [ position, direction.to_a, camera.up.to_a, fov, aspect_ratio, width, height]
     

model = Sketchup.active_model
view = model.active_view
target = camera.target
vector = target - position

if vector.x>0
  if vector.y>0
    az = Geom;;Vector3d.new(0,1,0).angle_between(vector).radians
  else
    az = Geom;;Vector3d.new(1,0,0).angle_between(vector).radians+Math;;PI/2
  end
else
  if vector.y<0
    az = Geom;;Vector3d.new(0,-1,0).angle_between(vector).radians+Math;;PI
  else
    az = Geom;;Vector3d.new(-1,0,0).angle_between(vector).radians+(3*Math;;PI/2)
  end
end

the first one is just the same as KS pulls out
the second bit is trying to see how they arrive at the azimuth...
I remember reading some where that SU reads from the camera 'film' plane and you need to subtract the length to the lens 'plane', or similar... [I can't find the link]
the API has to much misinformation about all of this...

john

chippwalters

Thanks for you help. I'll test your new code tomorrow when I get a moment.

The workaround I found seems to be doing the trick: Here's a model I built tonight and used a SU wireframe overlaid on top (autonomous mobile office meeting room for an article) and it seems to work pretty well . FWIW, the model is not complete...just WIP).

reptileslice

Can someone please summarize the working solution to this SKP>KS FOV + focal length 1:1 export dilemma. Super irritated with KS. Thanks for your consideration!

chippwalters

Last I checked, the latest KeyShot plugin seemed to be working.