Redirecting ray3 output

ray3.exe outputs to STDERR, so you cannot simply do this:

ray3 -v 6 test.mi > out.txt

You have to do something like this:

ray3 -v 6 test.mi 2>out.txt

In the above command, 2>out.txt redirects STDERR to the file out.txt.

Or you can do this, which redirects all output (STDOUT and STDERR) to out.txt:

ray3 -v 6 test.mi >out.txt 2>&1


Showing the Y coordinate of each point on a grid

Someone on the community forums was asking for a way to show the y coordinate of each point on a grid.

I gave it a quick try with ICE:

This ICE tree gets the point position, converts it to global coordinates, and stores it in an attribute. Then I just use Show Values (or an Attribute Display property) to show the coordinate value in the viewport:

Works ok but not great. The update is not interactive, you have to refresh the simulation to get the latest values displayed.