[solved] Double precision PLY file

#1

Hi,
I was having issues loading a double precision ply file
it was rendering out as just one tiny red dot.

The file has a header like this:

ply
format ascii 1.0
element vertex 147108
property double x
property double y
property double z
property uchar red
property uchar green
property uchar blue
property uchar alpha
end_header
-56.480445869086900 -8.691500902995344 -17.262350570142956 0 10 0 255
-53.565232666328555 -0.984290681444733 -1.777964295660240 0 8 0 255
-54.738413887972044 -7.486936924437444 -11.372097133213714 0 5 0 255
-56.300846355434494 -8.935164068605772 -19.639334616943870 0 8 0 255
-56.250092540388543 -14.375952135387607 -22.453811263470385 0 7 0 255
...

You can download an example here

After simply going in the header and changing “double” to “float” it was fixed, I was wondering if there is a trick I’m missing to be able to load double precision ply files, even if it converts it to a float in the process. I do have a python script that changes the header for me, but I am working with thousands of files, I wanted to see if there is a better way.

Also, (sanity check) what I’m feeling is the difference in fidelity between double and float precision is negligible/doesn’t matter (in my case) . Because OF is not using the full precision under the hood (?) and I really don’t see a difference in the point cloud quality between OF and other programs.

I write more about that process here

Also is it possible to add an intermediary tag to questions? I always feel like a beginner whos in too deep in advanced territory! hahaha

Thanks a bunch,
Char

#2

I don’t think using doubles would make any difference for visualizing. In any case as you point out OF doesn’t support doubles on meshes so it would be converted at some point to floats anyway.

you could modify the ply parser to support doubles by changing these conditions to also read double and not only float

if you do so and want to send a PR that would be super useful!

#3

Thank you for your response. Also thanks for showing me where to look, I’ll get on that PR :slight_smile:

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