Getting a polygonal version of an animated mesh

rui_mac

O need to get a polygonal version of any object wthat is animated (with keyframes or deformers).
My code, so far, is:

        curr_time = c4d.BaseTime(frame_start,doc_fps) + c4d.BaseTime(x,doc_fps)
        doc.AnimateObject(op,curr_time, c4d.ANIMATEFLAGS_NONE)
        doc.SetTime(curr_time)

        c4d.EventAdd(c4d.EVENT_FORCEREDRAW)
        c4d.DrawViews(c4d.DRAWFLAGS_FORCEFULLREDRAW)

        bc = c4d.BaseContainer()
        bc[c4d.MDATA_CURRENTSTATETOOBJECT_INHERITANCE] = True
        bc[c4d.MDATA_CURRENTSTATETOOBJECT_KEEPANIMATION] = True
        bc[c4d.MDATA_CURRENTSTATETOOBJECT_NOGENERATE] = False
        bc[c4d.MDATA_CURRENTSTATETOOBJECT_LOD] = 1.0
        bc[c4d.MDATA_CURRENTSTATETOOBJECT_BUILDFLAGS] = c4d.BUILDFLAGS_NONE

        clone_op = op.GetClone(flags=c4d.COPYFLAGS_NONE)

        res = c4d.utils.SendModelingCommand(command = c4d.MCOMMAND_CURRENTSTATETOOBJECT,
                                        list=[clone_op],
                                        mode=c4d.MODELINGCOMMANDMODE_ALL,
                                        bc=bc,
                                        doc=doc,
                                        flags=c4d.MODELINGCOMMANDFLAGS_NONE)

But the resulting object(s) inside the res list, seem to only result in the non-animated object.
How can I get the animated/deformed mesh?

m_adam

Hi @rui_mac please make sure to post in the correct category, for anything related to Cinema 4D please post into the CINEMA 4D DEVELOPMENT category (I've moved your topic)
Also, make sure to use the tagging system.

In regards to your code, few things to say.
First, there is no loop over time (so you never change the time of the current document)
Moreover, when you clone the object, the returned object is not inserted into any document so even if you copy an object with these animation data they are lost since there is no document to define the time.

Finally, a more suited approach is to use BaseObject.GetDeformCache which store the deformed state of an object.
Find an example here, I also attached a scene, select the cloner run the script it will create a Null based on the position of each clone

"""
Copyright: MAXON Computer GmbH
Author: Maxime Adam

Description:
    - Animates a BaseDocument from frame 5 to 20.
    - Retrieves all the deformed mesh from the selected object
    - Creates a Null for each frame at the position of point 88 of all deformed mesh

Class/method highlighted:
    - BaseObject.GetDeformCache()
    - c4d.BaseTime()
    - BaseDocument.SetTime()
    - BaseDocument.ExecutePasses()

Compatible:
    - Win / Mac
    - R16, R17, R18, R19, R20
"""
import c4d


def DeformedPolygonCacheIterator(op):
    """
    A Python Generator to iterate over all PolygonCache of passed BaseObject
    :param op: The BaseObject to retrieves all PolygonObject cache.
    """
    if not isinstance(op, c4d.BaseObject):
        raise TypeError("Expected a BaseObject or derived class got {0}".format(op.__class__.__name__))

    # Try to retrieves the deformed cache of the object
    temp = op.GetDeformCache()
    if temp is not None:
        # If there is a deformed cache we iterate over him, a deformed cache can also contain deformed cache
        # e.g. in case of a nested deformer
        for obj in DeformedPolygonCacheIterator(temp):
            yield obj

    # Try to retrieves the cache of the Object
    temp = op.GetCache()
    if temp is not None:
        # If there is a cache iterates over its, a cache can also contain deformed cache
        # e.g. an instance, have a cache of its linked object but if this object is deformed, then you have a deformed cache as well
        for obj in DeformedPolygonCacheIterator(temp):
            yield obj

    # If op is not a generator / modifier
    if not op.GetBit(c4d.BIT_CONTROLOBJECT):
        # If op is a PolygonObject we return it
        if op.IsInstanceOf(c4d.Opolygon):
            yield op

    # Then finally iterates over the child of the current object to retrieves all objects
    # e.g. in a cloner set to Instance mode, all clones is a new object.
    temp = op.GetDown()
    while temp:
        for obj in DeformedPolygonCacheIterator(temp):
            yield obj
        temp = temp.GetNext()


def main():
    # Saves current time
    ctime = doc.GetTime()

    # Retrieves BaseTime of frame 5, 20
    start = 5
    end = 20

    # Marks the state of the document as the initial step of our undo process
    doc.StartUndo()

    # Loops through the frames
    for frame in xrange(start, end + 1):
        # Changes the time of the document
        doc.SetTime(c4d.BaseTime(frame, doc.GetFps()))

        # Executes the document, so animation, dynamics, expression are calculated and cached are build accordingly
        buildflag = c4d.BUILDFLAGS_NONE if c4d.GetC4DVersion() > 20000 else c4d.BUILDFLAGS_0
        doc.ExecutePasses(None, True, True, True, buildflag)

        # For each cache objects of our current selected object
        for obj in DeformedPolygonCacheIterator(op):

            # Calculates the position of the point 88 in world space
            pos = obj.GetPoint(88) * obj.GetMg()

            # Creates a null for each frame and each cache
            null = c4d.BaseObject(c4d.Onull)
            null.SetName(str(frame))

            # Inserts the objects into the documents
            doc.AddUndo(c4d.UNDOTYPE_NEW, null)
            doc.InsertObject(null)

            # Defines the position of the null with the position of the point from the deformed mesh
            null.SetAbsPos(pos)

    # Sets the time back to the original time.
    doc.SetTime(ctime)

    # Executes the document, so animation, dynamics, expression are calculated and cached are build accordingly
    buildflag = c4d.BUILDFLAGS_NONE if c4d.GetC4DVersion() > 20000 else c4d.BUILDFLAGS_0
    doc.ExecutePasses(None, True, True, True, buildflag)

    # Marks the state of the document as the final step of our undo process
    doc.EndUndo()

    # Updates Cinema 4D
    c4d.EventAdd(c4d.EVENT_ANIMATE)


if __name__ == "__main__":
    main()

test_scene.c4d

If you have any question, please let me know.
Cheers,
Maxime.

rui_mac

Well, I do have a loop but I just pasted the code that would, hopefully, perform the calculation.
And I did tried the GetDeformCache approach, but my mistake was, in fact the cloning of the object.
Thank you so much for the code, Adam.