Querying CV's of a curve?

[jessec]

Hey.

I'm writing a script that will basically, take two CV control curves that are the same shape, only in different spots, and snap the curves of the first to the second.

The main problem I'm having right now is finding out how to query how many CV's make up each object. Anyone know how to go about doing this??? Any leads on useful commands or such would be much appreciated, thanks!

[joojaa]

no idea what your lalking about? the curves that are same shape do you mena they are instaces (than they use the same shape), or that they are shaped like each other? or do they share the same underworld (ie they are curves on surfaces)? You give not much clue about this.

Anyway, the number of cvs is spans + degree so

print (getAttr curve9.spans + getAttr curve9.degree); should yeld what you want

PS theres no difference between a cv and a ep curve,,, Just different imput methood thats all.

[jessec]

Uh oh... Now you've confused me.

Lol, but yeah, it's a duplicate of the same shape. Basically, I want to duplicate a NURBS curve, and then constrain the original nurbs shape to a joint... Only the curve flips all crazy to align itself with the joint, so then I'd be using the script to iterate through each point on the constrained object and move it to the world space coordinates of the duplicated object.

So, what you're talking about is for an actual NURBS shape, correct???

Here, here's a generic very basic beginning blocks of the code for now:

In reply to:
// Select original object first, then the duplicate to snap the points to:
string $selected[] = ls -sl;

// Find how many CV points in the object:

// Snap points of first to the points of second:
for ($x = 0; $x < $maxCVs; $x++)
{
$location[] = `xform -q -t -ws ($selected[1] + ".cv[" + $x + "]")`;
$original
}

[jessec]

Ok, that getAttr call was just what I needed, thanks!

EDIT: Oh! Got it working! Although, I'd also like to set it up to work with the first nurbs curve already having it's shape node parented to a joint, so I'd have to change it to specify using the joint's attached shape curves' spans. I'll have to look into that. Here it is so far though:

In reply to:global proc snapCurves()

{
// Select original object first, then the duplicate to snap the points to:
string $selected[] = ls -sl;
string $firstSel = $selected[0];
string $secondSel = $selected[1];
if (size $selected > 2)
error("Too many objects selected.");
if (size $selected < 2)
error("Please select two objects.");

// Find how many CV points in the object:
int $maxCVs = getAttr ($firstSel + ".spans");

// Snap points of first to the points of second:
int $x;
for ($x = 0; $x <= $maxCVs; $x++)
{
vector $loc = `xform -q -t -ws ($secondSel + ".cv[" + $x + "]")`;
// Move first selected object to second selected, vert by vert:
move -ws ($loc.x) ($loc.y) ($loc.z) ($firstSel + ".cv[" + $x + "]");
}

}

Any crits on coding efficiency and the like are welcome also, I'm still kinda new to this shtuff.

[joojaa]

int $maxCVs = getAttr ($firstSel + ".spans");

Ok so your limitting yourself to linear curves then? As said you need to add degree in to get the right amount of points for any curve of whatever degree.

[jessec]

Ohhhh, right. I was testing this with only linear curves. Thanks for pointing that out, I'll look into taking non-linear curves into consideration as well, thanks!