Hi, i made a very simple floor generator HDA. It works fine in houdini itself but when i import it to UE4 it instantly crashes unreal when i drag it to viewport. I made some trial and errors and problem is my object_merge node's parameter name. If i write “Curve Input” it crashes the unreal but if i just change name to something else doesnt involve word “curve”
for example just “Input” than it works. My other assets has exacly same name “Curve Input” and they work fine, only difference is floor generator asset uses closed curve ofc to generate surface. Is this a bug or am i doing something wrong?

Hi,

When naming your input with “curve”, the plugin will by default set that input to a curve input, which will create the default two points houdini curve…
This must be what's causing the issue, probably because your hda is expecting closed curves..

Could you send us your hda so I can have a look at the issue?

dpernuit
Hi,

When naming your input with “curve”, the plugin will by default set that input to a curve input, which will create the default two points houdini curve…
This must be what's causing the issue, probably because your hda is expecting closed curves..

Could you send us your hda so I can have a look at the issue?

hi, yea i think it's that, because i saw that two point line in unreal right before it crashes than it crashes. kinda weird but looks like i cant name it with word “curve” if it's closed one than :p another thing i want to ask curve related too; in unreal sometimes curve jumps to random height inside of wall when it should be at dead bottom of wall geo, this is happening in open curve, wall; not floor asset with closed curve. and when i look at houdini asset itself's tranform attributes in unreal i see random numbers when this happens. sorry for cant send actual assets because they are not mine. but will try to replicate similar one if you need it to help me, when i get home thank you so much for your help, im just trying to adapt to houdini.

Hi,

You could be handling that error case (not a closed curve, or a curve without enough points) by using a switch and a null after the input.

And use the following expression in the switch:

npoints(“../Curve_Input/”) > 2
or
nprims(“../Curve_Input/”) > 0

This should help catching the error, and avoid the crashes.

For your second issue, I'm not exactly sure what you mean, so please send me an hda to reproduce it if you can.

thank you so much, couldnt try it yet. my second issue was that: https://github.com/sideeffects/HoudiniEngineForUnreal/issues/61 [github.com] and seems like solved with that changing transform parameter to “none” like they said.