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How to get data points within current camera view?

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Simon
Simon on 22 Jun 2021
Commented: Simon on 24 Jun 2021
I have a scatter3 plot displaying some (3D) point cloud data. I then use the zoom, pan, rotate, ... interactions to find the scene I'm interessted in.
Now I'd like to get only the currently visible part of the point cloud data which is displayed in the plot. So what I'm looking for is something like a "reverse-function" of camlookat. camlookat moves the camera to view a given object. I'm looking for a function that gives me all objects (or point cloud data) for a given camera position.
I'm thinking about transforming all data into the coordinate system of the camera. One could then find all points which lie in the camera's field of view...
Any ideas / hints on this?
  1 Comment
Simon
Simon on 24 Jun 2021
To be a little more precise: I’m using pcshow, which apparently generates a scatter(3) plot.
load('xyzPoints');
h=pcshow(xyzPoints);
disp(h.Children.Type);
Output:
scatter
See my comment below.

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Answers (1)

Joseph Cheng
Joseph Cheng on 22 Jun 2021
Edited: Joseph Cheng on 22 Jun 2021
So... if i'm not mistaken pan in matlab moves the axes limits of the plot and not panning/translating the camera, similarly zooming as well. It not moving a camera/POV like in CAD/real life. Because of that if i have 2 points on the X axis at 0 and 100, then center and zoom in on 0 then rotate to look down the X axis to "see" x==100 is, it wouldn't draw depending on what the plotted x axis limit is. because of that couldn't you just orientate your view then use the axis handle to get the xlim, ylim and zlim of the 3d display to then bound the xyz point cloud for values within the xyz axes region?
  2 Comments
Joseph Cheng
Joseph Cheng on 23 Jun 2021
oof... not familiar with pcshow and don't have that toolbox... i'll come back if i think of anything from your pasted handles data

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