[Plugin] SketchyFFD (Classic)

Burkhard

First page!

plot-paris

since switching to SketchUp 7 I can only use the default 3x3 lattice. any user defined deformation matrix doesn't work (the lattice is created, but moving the points doesn't have any effect)...

gbabcock

Chris,

Thanks for the great plug-in, it really makes SU into a useful tool!

I think I found the cause of the problems some are having since with the 22 Aug update. The symptom is that once you use SketchyFFD, you can't change the size of the FFD. For example, if you create a 2x2 FFD you can only use a 2x2 for that session. Closing SU and reopening (or reloading the plug-in) clears it. Also NxN only works when all three dimensions are the same. At least that's what I have observed, and it seems consistent with the posts.

Starting on line 440 is the following:

[mod=:2y04bwod]THIS IS VERY OLD CODE, AND NO LONGER REGARDED AS GOOD-PRACTICE [$var ETC].
THE NEWEST VERSION OF FFD FROM THE PLUGINSTORE IS THE BEST AVAILABLE...[/mod:2y04bwod]

#Calculate the Bernstein polynomial.
#Uses a table for speed. 
#thanks to steven-arts for the idea.
$binomialTable=[]
def calcBernstein (i, n, u) #Bernstein Polynomial
    begin
        binomial=$binomialTable[i][n]
    rescue
        $binomialTable[i]=[] if($binomialTable[i]==nil)
        $binomialTable[i][n]=ffdfactorial(n).to_f / (ffdfactorial(n - i).to_f * ffdfactorial(i).to_f)
        binomial=$binomialTable[i][n]
    end
    #binomial = factorial(n).to_f / (factorial(n - i).to_f * factorial(i).to_f)
    bernstein = binomial * (u**i) * ((1-u)**(n-i))
    return(bernstein)
end

The 4th line of this section, "$binomialTable=[]", declares the array and initializes it empty. But it is BEFORE the function declaration, so it gets executed only on the initial program load. Once you dimension the array with "binomial=$binomialTable[i][n]" you can't change the dimensions without reinitializing it. I simply moved this line inside the function so it will reinitialize on each call and it works fine.

I've tested this in SU 7.1.860 with 2x2, 3x3, and random NxN FFD's in the same session with no problems. Hope this helps!

Glenn

plot-paris

well, that did the trick for me. thanks, Glenn.
however, there are still some issues sometimes. like that a transformation isn't applied to certain parts of the geometry.

and I have got two questions/suggestions for improvements for a future version:

when you undo an action, the deformation, that has been applied to the geometry will be undone. the changed position of the control vertexes however is not set back. thus, when you undo an unwanted deformation and then move some control vertexes again, the old (undone) transformation is simply added to the new transformation)
so my question is: is there a way to undo the repositioning of control vertexes alongside the undo-process of the geometry?
when you deform a group, then delete the lattice and then create a new ffd lattice, the array of control vertexes is shaped around the old position of the group. in order to correct this you have to explode and regroup the geometry.
I guess there is now easy way to overcome this problem. but if there was a possibility the plugin could reevaluate a groups position/scale, before creating the lattice, that would be cool.

mariocha

Yeah !, that modification came just in time. I needed it for work. Modeling a boat.
Great work.

As for the undo, for now I undo twice, one for the geom and one for the vertices. Seems to work fine.

Jim

Is Chris no longer maintaining this?

plot-paris

hey Glenn,

marvellous! now it works like a charm. a new matrix is always reliably adjusted to the group's dimensions and - for me even more important - undoing an operation effects geometry and control vertexes at the same time!

thank you very much for improving the script, Glenn

plot-paris

I do have a question about the workings of this plugin.

is the deformation a gradual process? (each change I make with the matrix adds another deformation to the geometry, therefore the order is important)

or is it only dependent on the matrix's final state? (no matter if i do 10 changes or a hundred, the final position of control vertexes is important)

because if the latter is the case (which I hope), you could - in theory at least - write a mighty modifier plugin not too much unlike 3Ds Max's deformers, where you can assign various preset-deformations to an object.
these modifiers are attached to the group, can be switched on/off or their attributes can be adjusted.
also you can add several modifiers (like a 'twist', a 'bend', and a 'squeeze' modifier). then the order is important (whether you twist or bend first), which of course can be changed later too...

I don't want to know how difficult/impossible it is to write such a script. but just imagine the capabilities! you would add a whole new level of non-destructive controls to SketchUp

thomthom

@gbabcock said:

OK, here's the latest update. This one should fix the problems with control points and subdividing being misaligned with the deformation group.

I'd appreciate any feedback to let me know if it's working well.

Glenn

Maybe better to create a new thread - so the download is at the start of the thread - not buried somewhere randomly in between. If you do that I'll tab this one obsolete and add a link to the new version.

Plasticbricks

Hi guys,

I've installed the SketchyFFD plugin by dropping it into my plugins folder but cannot locate it in SU. How do I access it/ turn it on?

Thanks.

massimo

Hi and welcome . You will find FFD in the context menu (right click). Oh, and remember that this plugin works on grouped geometry.

markbowen

Hiya,

Sorry for effectively bumping this post for everyone again but I'm having a real problem getting this plugin to work so was wondering if someone could possibly help?

I tried by creating a simple cube, grouping everything and then running the FFD 2x2 on it. I see the point grid appear but then I'm not too sure what to do. I can't select points easily and when I do all that happens is that the points move but the object doesn't change in any way at all, just the points move

Has anyone ever seen that before and knows what might be causing this?

Many thanks for any help on this.

Best wishes,

Mark

solo

mark

Once you have made the cube a group, right click and select the FFD you want, then click on one of the small black crosses to edit the form. Now you can move, scale, rotate one or multiple crosses to deform the shape.
When completed close group and delete FFD transformer group.

solo

Here is a video of what I mean.

Dropbox - 404

(dl.dropbox.com)

markbowen

Thanks. I've finally got the mesh working although sometimes it doesn't always do anything. Probably me being silly or something though.

Off to give some of that a try now.

Many thanks for the help on this.

Best wishes,

Mark

Kman

Great! A little confusing, but great!

daedaluz

Cool! It is very useful and amazing tool. Thanks!

chouaibcl65

thank you

jeabdc

ThankYou for your Plugins.
ขอบคุณมากครับ(Thailand is Smile Land)

chobs

Hi to all. Having a problem when I make an FFD Patch.

Here's the message:

Error: #<ArgumentError: wrong number of arguments(2 for 3)>
C:/Program Files/Google/Google SketchUp 7/Plugins/SketchyFFD.rb:106:in startFFD' C:/Program Files/Google/Google SketchUp 7/Plugins/SketchyFFD.rb:106:in init'
C:/Program Files/Google/Google SketchUp 7/Plugins/SketchyFFD.rb:83:in `call'