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1:08 p.m.
Hi,
I've figured out I can have an auto-resize based on the density field by
bringing it in sop and convert it to iso with a "Convert Volume Sop".
Than I use that geo on a "Gas Resize Fluid" to do the automatic resize
based on its bounding box.
I'm going to create a hda for that but I'm wondering if I'm missing
something and reinventing the wheel. Is it already possible to it
directly with "Gas Resize Fluid" or an other node inside dop?
Fran?ois
1:26 p.m.
Hi Fran?ois,
http://www.cmivfx.com/tutorials/view/276/Houdini+Smoke+And+Dust
There is a comparable method discussed in this video that uses a scatter ->
bbox within a sop solver.
Sounds very similar to what you're talking about, but the scatter might save
you a few cycles over a volume conversion.
best,
mike
2011/3/24 Fran?ois Duchesneau <sidefx at trinix.ca>
Hi,
I've figured out I can have an auto-resize based on the density field by
bringing it in sop and convert it to iso with a "Convert Volume Sop". Than I
use that geo on a "Gas Resize Fluid" to do the automatic resize based on its
bounding box.
I'm going to create a hda for that but I'm wondering if I'm missing
something and reinventing the wheel. Is it already possible to it directly
with "Gas Resize Fluid" or an other node inside dop?
Fran?ois
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2:05 p.m.
Hi,
We put together something based on the scatter approach as an OTL. It
has been working well for us so far. Our approach is a bit more
complicated then just taking the field you want resize with (ie density
or temperature) because we ran into trouble with fast moving sources.
The quick outline is:
otl with a sop solver feeding into a gas resize field.
within the sop solver:
1)Dop import pulling the field you want to use as the resize field,
scatter into that dop import.
2)object merge your source (emitter) sop,
scatter into this source.
3)Merge these two and bound the result.
4)Padding on the final output bound is used to adjust for
velocity of fluid to prevent clipping
5)We also added in a clip limit feature to limit the size of
the result based on a sop input.
The rough idea for this method came from conversations with sidefx.
I agree with Michael that the scatter might be a bit lighter.
On 03/24/2011 10:26 AM, Michael Dunkley wrote:
Hi Fran?ois,
http://www.cmivfx.com/tutorials/view/276/Houdini+Smoke+And+Dust
There is a comparable method discussed in this video that uses a scatter ->
bbox within a sop solver.
Sounds very similar to what you're talking about, but the scatter might save
you a few cycles over a volume conversion.
best,
mike
2011/3/24 Fran?ois Duchesneau<sidefx at trinix.ca>
> Hi,
>
> I've figured out I can have an auto-resize based on the density field by
> bringing it in sop and convert it to iso with a "Convert Volume Sop". Than
I
> use that geo on a "Gas Resize Fluid" to do the automatic resize based on
its
> bounding box.
>
> I'm going to create a hda for that but I'm wondering if I'm missing
> something and reinventing the wheel. Is it already possible to it directly
> with "Gas Resize Fluid" or an other node inside dop?
>
> Fran?ois
> _______________________________________________
> Sidefx-houdini-list mailing list
> Sidefx-houdini-list at sidefx.com
> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>
>
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--
Bill Watral
FX | TD
x4720
2:35 p.m.
Bills message just reminded me of something for dealing with the fast fluids
issue - I've seen an implementation where the scattered points are first
advected by the velocity field using a vop in the sop solver, then mixed in
with the unadvected points before piping into the bbox. We haven't set it
up here yet but certainly seems worth it. And fwiw I'd definitely second
the clip limits/geo option - unbounded sims can go all sorts of places you
just don't care about.
mike
On Thu, Mar 24, 2011 at 2:05 PM, Bill Watral <bwatral at pixar.com> wrote:
Hi,
We put together something based on the scatter approach as an OTL. It has
been working well for us so far. Our approach is a bit more complicated then
just taking the field you want resize with (ie density or temperature)
because we ran into trouble with fast moving sources.
The quick outline is:
otl with a sop solver feeding into a gas resize field.
within the sop solver:
1)Dop import pulling the field you want to use as the resize field,
scatter into that dop import.
2)object merge your source (emitter) sop,
scatter into this source.
3)Merge these two and bound the result.
4)Padding on the final output bound is used to adjust for velocity
of fluid to prevent clipping
5)We also added in a clip limit feature to limit the size of the
result based on a sop input.
The rough idea for this method came from conversations with sidefx.
I agree with Michael that the scatter might be a bit lighter.
On 03/24/2011 10:26 AM, Michael Dunkley wrote:
> Hi Fran?ois,
>
> http://www.cmivfx.com/tutorials/view/276/Houdini+Smoke+And+Dust
>
> There is a comparable method discussed in this video that uses a scatter
> ->
> bbox within a sop solver.
> Sounds very similar to what you're talking about, but the scatter might
> save
> you a few cycles over a volume conversion.
>
> best,
> mike
>
> 2011/3/24 Fran?ois Duchesneau<sidefx at trinix.ca>
>
>
>
>> Hi,
>>
>> I've figured out I can have an auto-resize based on the density field by
>> bringing it in sop and convert it to iso with a "Convert Volume Sop".
>> Than I
>> use that geo on a "Gas Resize Fluid" to do the automatic resize based
on
>> its
>> bounding box.
>>
>> I'm going to create a hda for that but I'm wondering if I'm missing
>> something and reinventing the wheel. Is it already possible to it
>> directly
>> with "Gas Resize Fluid" or an other node inside dop?
>>
>> Fran?ois
>> _______________________________________________
>> Sidefx-houdini-list mailing list
>> Sidefx-houdini-list at sidefx.com
>> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>>
>>
>>
> _______________________________________________
> Sidefx-houdini-list mailing list
> Sidefx-houdini-list at sidefx.com
> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>
>
--
Bill Watral
FX | TD
x4720
2:57 p.m.
All makes sense guys. I'll implement it this way and yes it's faster
with scattered points instead of "Convert Volume Sop", I tested it.
Thanks
Fran?ois
Michael Dunkley wrote:
Bills message just reminded me of something for dealing with the fast
fluids
issue - I've seen an implementation where the scattered points are first
advected by the velocity field using a vop in the sop solver, then mixed in
with the unadvected points before piping into the bbox. We haven't set it
up here yet but certainly seems worth it. And fwiw I'd definitely second
the clip limits/geo option - unbounded sims can go all sorts of places you
just don't care about.
mike
On Thu, Mar 24, 2011 at 2:05 PM, Bill Watral <bwatral at pixar.com> wrote:
> Hi,
>
> We put together something based on the scatter approach as an OTL. It has
> been working well for us so far. Our approach is a bit more complicated then
> just taking the field you want resize with (ie density or temperature)
> because we ran into trouble with fast moving sources.
>
> The quick outline is:
>
> otl with a sop solver feeding into a gas resize field.
> within the sop solver:
>
> 1)Dop import pulling the field you want to use as the resize field,
> scatter into that dop import.
>
> 2)object merge your source (emitter) sop,
> scatter into this source.
>
> 3)Merge these two and bound the result.
>
> 4)Padding on the final output bound is used to adjust for velocity
> of fluid to prevent clipping
>
> 5)We also added in a clip limit feature to limit the size of the
> result based on a sop input.
>
>
> The rough idea for this method came from conversations with sidefx.
> I agree with Michael that the scatter might be a bit lighter.
>
>
>
>
>
>
> On 03/24/2011 10:26 AM, Michael Dunkley wrote:
>
>
>> Hi Fran?ois,
>>
>> http://www.cmivfx.com/tutorials/view/276/Houdini+Smoke+And+Dust
>>
>> There is a comparable method discussed in this video that uses a scatter
>> ->
>> bbox within a sop solver.
>> Sounds very similar to what you're talking about, but the scatter might
>> save
>> you a few cycles over a volume conversion.
>>
>> best,
>> mike
>>
>> 2011/3/24 Fran?ois Duchesneau<sidefx at trinix.ca>
>>
>>
>>
>>
>>> Hi,
>>>
>>> I've figured out I can have an auto-resize based on the density field by
>>> bringing it in sop and convert it to iso with a "Convert Volume
Sop".
>>> Than I
>>> use that geo on a "Gas Resize Fluid" to do the automatic resize
based on
>>> its
>>> bounding box.
>>>
>>> I'm going to create a hda for that but I'm wondering if I'm
missing
>>> something and reinventing the wheel. Is it already possible to it
>>> directly
>>> with "Gas Resize Fluid" or an other node inside dop?
>>>
>>> Fran?ois
>>> _______________________________________________
>>> Sidefx-houdini-list mailing list
>>> Sidefx-houdini-list at sidefx.com
>>> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>>>
>>>
>>>
>>>
>> _______________________________________________
>> Sidefx-houdini-list mailing list
>> Sidefx-houdini-list at sidefx.com
>> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>>
>>
>>
> --
> Bill Watral
> FX | TD
> x4720
>
>
>
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