Both positive and negative (u,v) coordinates

[jwatson-CO-edu]

Model: D405

I am attempting to interpret the uv coordinates in order to generate an XYZRGB point cloud in python. I do not understand what is meant when V takes on both positive and negative values. I attempted to follow this guide:

The mapping of (u,v) to a color pixel is:
For {u/v} : [0-1] --> [0-{width-1/height-1}], Meaning that
(0,0) is mapped to (0,0)
(0,1) is mapped to (0,height-1)
(1,0) is mapped to (width-1,0)
(1,1) is mapped to (width-1,height-1)

We do not provide a function that takes texture (u, v) and returns RGB (r, g, b, a), mainly because mostly rendering libraries take texture parameters and will handle it on their own. But you can do the mapping yourself if you wish by converting texture to pixel using the above explanation.

Originally posted by @zivsha in #1231 (comment)

To produce

pc = rs.pointcloud()
pc.map_to( colFrm )
points = pc.calculate( depFrm )
vtx = np.asarray( points.get_vertices(2) )
tex = np.asarray( points.get_texture_coordinates(2) )
col = np.zeros( (vtx.shape[0], 3), dtype = int )

for k, uvCoord in enumerate( tex ):
    i = int( min( uvCoord[0], 1.0) * (self.cols-1) )
    j = int( -uvCoord[1] * (self.rows-1) )
    print( uvCoord, i ,j )
    col[k,:] = colImg[j,i,:]

Somtimes UV is [ 0.09909751 -0.05718123] and sometimes it is [0.39045626 0.36308518].
Also, it was necessary for me to clip U to 1.0 in this scheme.

[jwatson-CO-edu]

The Open3D library has facilities for this:
https://github.com/correlllab/MAGPIE/blob/PDDLStream_Testing/40_blocks_detect/42_Get-PCD-Color.ipynb
Although I do not understand the negative V values or U values greater than 1.0, I no longer need to. Issue closed.