hi. i had several question about mantra. i asked them before but i got no answer. :cry:

1. i want to do some very simple rendering in houdini using mantra. consider a cube on a suface. no shaders no material. nothing. can i make this really fast? i mean turning off some features of mantra that i don't need in this case so that i can render very fast.

2. most apps have things like world or environment that are rendered as a background. for example i have a photo of the sky at night and i want it to be rendered behind an object i have modeled in houdini. how can i do it? ( without compositing of course)

1./ Mantra cannot render simple scenes very fast – there is a some overhead for all the versatility Mantra has. Mantra starts to shine when scenes get more complex.

2./ Look into the vm_background property (find it on http://www.sidefx.com/docs/houdini10.0/props/mantra10_0) [sidefx.com]

For #1, the viewport flipbook feature in H11 can render simple scenes very quickly, with AA, HDR, shadows, screen-space ambient occlusion and accurate lighting for most light types. Normal, specular, bump and reflection maps are also supported. If you're looking for pure rendering speed for simple scenes, this is the way to go.

thank you both.
for the first i think we don't have this option in houdini 9.5 which i am using now( h10 slow on my pc). isn't there any way to get the same effect in some other way?

and i have another question. can we have a real sky in houdini? i mean like terragen vue etc.. cause i've seen such a thing in Blender thought maybe it exists in houdini too. for example sun atmosphere and stuff.

4. how can i specify which objects i want to take light from a specific lamp or to be rendered or not?

5. this is about shading. not rendering. how can i for example add a cloud texture like other apps to a very basic material?

ramin22
4. how can i specify which objects i want to take light from a specific lamp or to be rendered or not?

Hi,

Try using the light linker - see screenshot for where to find it.

For render/no render control, use the “Render” tab in ht Parameters Pane while you select any object.
For more in-depth control, you can also click the “Gear” menu in the Parameters Pane (for each object separately) and "Edit Parameters Interface" for the node.

Cheers,
Greg