NURBS curves

From DreamsteepWiki

NURBS CURVES

import maya.OpenMaya as OpenMaya

import maya.OpenMayaMPx as OpenMayaMPx

import sys, math



kPluginCmdName="keither"



kPitchFlag = "-p"

kPitchLongFlag = "-pitch"

kRadiusFlag = "-r"

kRadiusLongFlag = "-radius"



# command

class scriptedCommand(OpenMayaMPx.MPxCommand):

	def __init__(self):

		OpenMayaMPx.MPxCommand.__init__(self)

	

	def doIt(self, args):

		deg = 3

		ncvs = 100

		spans = ncvs - deg

		nknots = spans+2*deg-1

		radius = 4.0

		pitch = 0.5

		

		# Parse the arguments.

		argData = OpenMaya.MArgDatabase(self.syntax(), args)

		if argData.isFlagSet(kPitchFlag):

			pitch = argData.flagArgumentDouble(kPitchFlag, 0)

		if argData.isFlagSet(kRadiusFlag):

			radius = argData.flagArgumentDouble(kRadiusFlag, 0)



		controlVertices = OpenMaya.MPointArray()

		knotSequences = OpenMaya.MDoubleArray()



		# Set up cvs and knots for the helix

		#

		#for i in range(0, ncvs):

		#	controlVertices.append( OpenMaya.MPoint( radius * math.cos(i),math.cos(i),radius * math.sin(i) ))

		#	#controlVertices.append( OpenMaya.MPoint( 0,i ))

		POINTS = [ [0,0,0],[1,1,0],[5,5,5],[1,3,0],[0,4,0] ]

                #controlVertices.append( OpenMaya.MPoint( 0,0,0) )
                for pnt in POINTS:
                    print pnt
                    controlVertices.append( OpenMaya.MPoint( pnt[0],pnt[1],pnt[2]) )



		for KVINDEX in range( ((len(POINTS)+ deg)-1 ) ):
                    knotSequences.append( KVINDEX )


		# Now create the curve

		#

		curveFn = OpenMaya.MFnNurbsCurve()

		

		nullObj = OpenMaya.MObject()



		try:

			# This plugin normally creates the curve by passing in the

			# cv's.  A function to create curves by passing in the ep's

			# has been added.  Set this to False to get that behaviour.

			#

			if True:

				curveFn.create( controlVertices,

								knotSequences, deg, 

								OpenMaya.MFnNurbsCurve.kOpen, 

								0, 0, 

								nullObj )

			else:

				curveFn.createWithEditPoints(controlVertices,

								3, OpenMaya.MFnNurbsCurve.kOpen,

								False, False, False)

		except:

			sys.stderr.write( "Error creating curve.\n" )

			raise



# Creator

def cmdCreator():

	# Create the command

	return OpenMayaMPx.asMPxPtr( scriptedCommand() )



# Syntax creator

def syntaxCreator():

	syntax = OpenMaya.MSyntax()

	syntax.addFlag(kPitchFlag, kPitchLongFlag, OpenMaya.MSyntax.kDouble)

	syntax.addFlag(kRadiusFlag, kRadiusLongFlag, OpenMaya.MSyntax.kDouble)

	return syntax



# Initialize the script plug-in

def initializePlugin(mobject):

	mplugin = OpenMayaMPx.MFnPlugin(mobject, "Autodesk", "1.0", "Any")

	try:

		mplugin.registerCommand( kPluginCmdName, cmdCreator, syntaxCreator )

	except:

		sys.stderr.write( "Failed to register command: %s\n" % kPluginCmdName )

		raise



# Uninitialize the script plug-in

def uninitializePlugin(mobject):

	mplugin = OpenMayaMPx.MFnPlugin(mobject)

	try:

		mplugin.deregisterCommand( kPluginCmdName )

	except:

		sys.stderr.write( "Failed to unregister command: %s\n" % kPluginCmdName )

		raise