GPU and Hairfarm

[MattClark]

Been having a little play with Hairfarm on the GPU, and it's a great addition. One thing that seems problematic though is that it will only render the amount of strands shown in the viewport. It's common to have this set to small percentage of the actual final render output to speed up the viewport display. I've found that by ticking 'show all hairs in viewport' in the Hair Generate modifier I can get it to render right in RT, but it can be very slow with big hair systems. (This can be helped by 'using display as box' in the object settings)

Can this be 'fixed'?

[MattClark]

Looks like the trick is to have "Show all hairs in viewport" ticked in the Hair Generate modifier, but have 'Hair Display Mode' set to 'Hair Mesh' in the Hair Display Modifier, that way it doesn't kill the viewport.

[vlado]

Can this be 'fixed'?

There are workarounds, but it's a sore issue in general (for Ornatrix too). Objects in 3ds Max can be in either of two states - viewport or rendering, and switching between those two states is expensive (f.e. all hairs need to be regenerated) so we don't do that for V-Ray RT. But if you set the viewport hairs to be the full number then the viewports become too slow... not sure what would be the best way to solve this.

Best regards,
Vlado

[MattClark]

....if you set the viewport hairs to be the full number then the viewports become too slow... not sure what would be the best way to solve this.

My suggestion above does seem to work well for Hairfarm, can't comment on Ornatrix...