Hello again!
I’m looking for a way to remove smoke from my simulation, suck it into a point even.
Simply setting up a source with negative smoke amount didn’t work and using vortex/gravity space warps will attract the smoke, but after a while it will explode due to heavy compression.
Has anyone created some black hole like effect with fumeFX before or has an idea on how to solve this?
Thanks!
-Sascha
Simulate smoke explosion and play it backward, by reversing frames in postproduction perhaps?
Hey!
Yes, I though of that too. Problem is, I want the smoke to come from one point, have some fun and then get sucked in by another point, so I need something to attrach and erase it.
Edit: There might be a way to do this with maxscript. I’ll report back if it works. 
Maybe you can achieve something like this in conjunction with PFlow and the FindTarget Operator !?
Yes I will certainly have a look at PFlow aswell, as it seems even better suited for what I want to do.
But for now I’ll use FumeFX with maxscript, since I have more experience with them and a deadline closing in.
Edit: The maxscript black hole works. Pretty straight forward actually … reduce smoke, change velocity, tweak, done.
Show something and tell a bit more about the method if you can, im really interested how you solved it!?
greetz
You could do it with strong gravity point.
Share us with effect you achieved if you can, please.
The gravity thing doesn’t work, because it compresses the fluid so much that at some point it will just explode. Gives you funky wave-like patterns.
Not sure if I’m allowed to post this, so keep your mouth shut. 
fn PreSim = (
global nBlackHole = getNodeByName "FumeFX Black Hole" --GRAVITY NODE USED FOR BLACK HOLE -- ICONSIZE = RANGE -- STRENGTH = ATTRACT SPEED -- DECAY = SMOKE REDUCTION AMOUNT -- RANGE INDICATORS = KEEP SPEED DIRECTION
if classOf nBlackHole == gravity then
(
ffxPrintToStatus "FOUND BLACK HOLE NODE!!!"
ffxPrintToStatus nBlackHole.name
ffxPrintToStatus "FOUND BLACK HOLE NODE!!!"
)
)
-- after velocity has been pressure corrected. you can make further adjustments to the velocity,
-- and also you can prepare other values - temp, smoke... - which will be moved next
fn PostPressure = (
if classOf nBlackHole == gravity then
(-- BLACK HOLE REQUIRES GRAVITY SPACE WARP
--BOUNDINGBOX OF BLACK HOLE IN FUMEFX VOCEL SPACE
local p3BlackHoleBoundingBoxStart = ffxWorldPtToVoxel (nBlackHole.pos - [nBlackHole.iconSize,nBlackHole.iconSize,nBlackHole.iconSize])
local p3BlackHoleBoundingBoxEnd = ffxWorldPtToVoxel (nBlackHole.pos + [nBlackHole.iconSize,nBlackHole.iconSize,nBlackHole.iconSize])
for i in 1 to 3 do
(--CLAMP BLACK HOLE BOUNDING BOX TO SIMULATION BOUNDING BOX
local iCurrentMax = case i of
(
1: (nx-1)
2: (ny-1)
3: (nz-1)
)
p3BlackHoleBoundingBoxStart[i] = aMax #(p3BlackHoleBoundingBoxStart[i],0)
p3BlackHoleBoundingBoxEnd[i] = aMin #(p3BlackHoleBoundingBoxEnd[i],iCurrentMax)
)
--REDUCE SMOKE AS IT GETS CLOSER TO THE BLACK HOLE - ATTRACT VELOCITY TO CENTER OF BLACK HOLE
for i in p3BlackHoleBoundingBoxStart.x to p3BlackHoleBoundingBoxEnd.x do
(
for j in p3BlackHoleBoundingBoxStart.y to p3BlackHoleBoundingBoxEnd.y do
(
for k in p3BlackHoleBoundingBoxStart.z to p3BlackHoleBoundingBoxEnd.z do
(
if (GetSmoke i j k) > .001 then
(--THRESHOLD TO AVOID COMPUTATION FOR EMPTY VOXELS
local p3VoxelInWorld = ffxVoxelPtToWorld [i,j,k] --WORLD POSITION OF CURRENT VOXEL
local fFalloff = aMin #(((distance p3VoxelInWorld nBlackHole.pos)/nBlackHole.iconSize), 1.0) --FALLOFF AT CURRENT VOXEL -- 0 AT CENTER, 1 AT RANGE END
local fFalloffWithDecay = pow fFalloff nBlackHole.decay --FALLOFF AT CURRENT VOXEL -- 1 AT CENTER, 0 AT RANGE END -- WITH DECAY
local p3AttractVelocity = (normalize (nBlackHole.pos - p3VoxelInWorld)) * nBlackHole.strength --VELOCITY VECTOR TO BLEND WITH VOXEL'S VELOCITY
if nBlackHole.hoopson then
(--KEEP SPEED DIRECTION WHEN RANGE INDICATORS TAGGED
p3AttractVelocity = p3AttractVelocity*(1-fFalloff) + (GetVel i j k)*fFalloff
)
SetSmoke i j k ((GetSmoke i j k) * fFalloffWithDecay) --REDUCE SMOKE ACCORDING TO DISTANCE TO BLACK HOLE
SetVel i j k ((GetVel i j k)*(1-fFalloff) + p3AttractVelocity*fFalloff) --SET VELOCITY ACCORDING TO DISTANCE TO BLACK HOLE
)
)
)
)
)
)
Basically it attracts the smoke and slowly dissipates it at the same time - so no compression and no explosion.
Just a quick hack - not user-friendly or anything.
Requires a gravity node called “FumeFX Black Hole” (just palce it in the scene - do not add to fumeFX sim!).
a bit late,
maybe try to animate it back wards (start @ end frame) and then go back for the same effect not sure if it will work
if you have thinking particles you can try setting up an orbit system and have the particles simply delete once they reach the point or “black hole” I actually believe there’s a scene file that comes with TP about this. I’m sure the same effect can be recreated with pflow, but I simiply haven’t used pflow in a bit.
I would maybe emit from a circle while using a combination of max’s vortex and pflows find target possibly. Give that a shot. Depending on the look you want , maybe add fumefx follow in the mix to get some more detail.
Hi Harefort:
I am working on a animation which need fire-vortex kind of effect. I try to run your script but shows this error:
PreSim()
– Error occurred in PreSim()
– Frame:
– Runtime error: You must register FumeFX with ffxRegister ($name) or use simulation-callback functions.
I can’t find any info about the ffxRegister over the internet, could you give me some help?
Hammer Chen
Go to the bottom of the general page of your fumeFX container and you will see a max script rollout, press edit and paste it in there, then save it, make sure “Use” is checked and simulate.
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.