The Laplacian flow is a geometric flow introduced by Robert
Bryant as a way for finding torsion free G2-structures.

Hooray for English language! Now what does that mean?

tamte

Dave_ah

tamte

Dave_ah
For Maya users equivalent MEL code would be
pscale *= .9 ;

so why wouldn't you try the same? (instead of trying == which is comparison of equality and not an assignment)

@pscale *= 0.9;

assuming you run it in DOP environment, like Solver SOP or directly DOP net

pscale *= .9 ;
Does not work in SOP level pointWrangle and attributeWrangle SOPs. Houdini generates syntax error and bypasses the SOP node.

you forgot @ to bind to pscale attribute

here is an example in plain SOPs where this will be applied once to incoming value

and also inside of Solver SOP where it will be applied every timestep

What is the difference between $pscale and @pscale in VEX? @pscale reads like Py.
Overall how does Houdini treat, in expression, @attribute vs. $attribute .

tamte

Dave_ah
For Maya users equivalent MEL code would be
pscale *= .9 ;

so why wouldn't you try the same? (instead of trying == which is comparison of equality and not an assignment)

@pscale *= 0.9;

assuming you run it in DOP environment, like Solver SOP or directly DOP net

pscale *= .9 ;
Does not work in SOP level pointWrangle and attributeWrangle SOPs. Houdini generates syntax error and bypasses the SOP node.

For Maya users equivalent MEL code would be
pscale *= .9 ;

I Just cannot get this syntax right.

In either pointWrangle SOP or attributeWrangleSOP
To scale a float attribute (pscale) per point per time step.
@pscale == .9 ;
or
$pscale == .9 ;

No good
What am I getting wrong?

Can two open sessions of Houdini on same machine talk to each other. See each other's data without having to cache first or copy/paste, or referencing a scene.
For example Merge Object SOP from session 1 (PID 6088) by session 2 (PID 91256) for example.

Thank you.

Simple question . Is POPFluid inside POPforces an SPH solver?
Smooth Particle Hydrodynamic solver , like in ole' RealFlow, which is still my favorite.

Thank you.

In POPForces their is a KILL POP (DOPs) and it has a nice feature that confines effect of the KillPOP to a bounding volume or geometrySOP. This is really nice.
Now how can other other fields, forces, and microsolvers be confined to particular volume?
For example POPWind be confined within a sphere, cylinder, or box.
I tried SOP input but that does not appear to work.

Thank you

happybabywzy
Hi,I know how to use vop ,but i would like to know what is the full name for VOP(sop vop)?

Is it means "visualize operator" or "vex operator"?

Not quite VOP . VOP is acronym for Vector Operations. Where use of VEX )Vector expressions) takes place. In 3D a vector is a compound value compised of three float numbers. Position (P) is a vector, compised of X,Y,Z coordinates. Common vectors are velocity, which is direction transform(movement) of point in 3D space. Color is a vector, composed of three color components. RGB, HSV, and other color models are vectors. There is also 4 component vectors that can be used as COLOR+ALPHA.

Vector is composed of component floating point numbers. A float is a single dimension number, describing quantity of attribute that are only defined by single component. Point ID is a n integer , a whole number variant of float. Point Scale (pscale), mass, density attributes are examples of float. Floating point numbers , just decimals, theoreticaly have no precision limits. PI (3.14646XXXXXXXXXXXX) is a floating point value. Houdini suppourts 16, 32, and 64 bit floating numbers which is way more then average user may need.
Houini CHOPs (chanel operators), aka MotionFX, produce single chanell floating point data. Can be used to create vectors also.

toadstorm
Hi Dave,

That's my blog, and coincidentally I also am the creator of MOPs.

MOPs stands for "Motion Operators"... it's a collection of HDAs originally built to help motion designers. It has a lot of tools applicable to motion graphics as well as VFX and is used widely in both industries.

You can read more about MOPs and download it here: https://www.motionoperators.com [www.motionoperators.com]

That tutorial on my blog doesn't require you to use MOPs at all... it just mentions a number of places where it can make your life easier.

How do you install MOPs for 19.5.569? They seem to have maxed out at HOudini is 17.X.XXX .

toadstorm
Hi Dave,

That's my blog, and coincidentally I also am the creator of MOPs.

MOPs stands for "Motion Operators"... it's a collection of HDAs originally built to help motion designers. It has a lot of tools applicable to motion graphics as well as VFX and is used widely in both industries.

You can read more about MOPs and download it here: https://www.motionoperators.com [www.motionoperators.com]

That tutorial on my blog doesn't require you to use MOPs at all... it just mentions a number of places where it can make your life easier.

I am having problen with Instancer CopyPoints using Attribute from peices technique. Its not working for me. I beleive its for a simple reason. The technique description lacks context and content of individual nodes. Without desctiption as what settings are used in nodes, context is lacking, and result is error.

So when forEach loop instancer result is exported into Alembic (ABC) the resulting file is large with instances combined into a single mesh, and velocity (v), Cd attributes appear to either not saved or not being loaded by Alembic loader SOP.

Any ideas aand suggestions?

Somehow I got it working. Not sure why.
It started working when changed syntax in Switch SOP spare input Name to spare_input0.

Go figure!

I do not understand the error or error message. I am following example by rote, yet error persists.
Please look at screen grab.
The rror fails to connect switch SOP to foreach_begin1 SOP despite the fact that it works in example. I have no explanation.

What is a MOP and where are the nodes?

In 19.5.569 and I don't see them.
I am trying to use ATTRITBUTE FROM PEICES Instancer technique from https://www.toadstorm.com/blog/?p=942 [www.toadstorm.com] and it just simply not working at all for me.
Thank you

How would that work in reverse , if additional geometry is added? Lets say an unrolled surface is scatterSOP with points then Copy To Points SOP is used to populate the surface. Then previously unrolled surface is rolled back to original shape. What I find is happening when Attribute Swap SOP is inversed is that added points are collapsed into same P as on original surface.

tamte
if your UVs are on vertices use Split UV Seams from sop Tab menu, check Promote To Point Attribute
then or if uvs were on points to begin with use Attribute Swap SOP (Mode: Copy, Source: uv, Destination: P)

That did the trick. Thank you

Unfold or unroll SOP geometry using UV. Has anyone figured out how do this in SOPs? Basically translating UV coordinate of point to its world coordinates on a XZ plane, and vice versa.

According to manual
MMB pbrings up TAKE information
RMB brings up TAKE menu (where TAKE can be deleted)

On my Windows, MMB and RMB over TAKE button does not work. Thus no way, that I can see, to delete a take.

Help!

Principled Mnatra shader refuses to honor keyframes in color and emission intensity channels.

Weird huh? Basically if there are keyframes in color or float (intensity) chanells, the shader will only render with 1st keyframe

For example . Keyframe on base color at frame 1 with pure yellow (255,255,0) animating to frame 10 blue (0,0,255), the object with this shader will render yellow only.
Is this a silly bug or is there a workaround.