Hi,in another post I found a way to achieve my goal of converting the coordinate position to camera space and then scaling it to a small size so that he appears first.

this is new code:

def Draw(self,op, drawpass, bd, bh):
    
    
    if not op[c4d.S_MOTIONTRAIL_GTWO_DRAWENABLE]:
        return c4d.DRAWRESULT_OK
    #bd.SetMatrix_Matrix(None, c4d.Matrix())
    pmg = ~bd.GetMg()
    bd.SetMatrix_Camera()

    all_pos = self.parameters['all_pos']
    color_lis = self.parameters['color_lis']
    point_size = op[c4d.S_MOTIONTRAIL_GTWO_POINTSIZE]
    bd.SetPointSize(point_size)
    for per_pos,color in zip(all_pos,color_lis):
        bd.SetPen(color)
        cnt = len(per_pos)
        temp_lis = []
        for i in xrange(cnt-1):
            c = (pmg * per_pos[i]).GetNormalized() * 20
            f = (pmg * per_pos[i+1]).GetNormalized() * 20
            bd.DrawLine(c,f,c4d.NOCLIP_D)
            temp_lis.append(c)
        temp_lis.append(f)
        bd.DrawPoints(temp_lis)
    

    return c4d.DRAWRESULT_OK

why * 20 will work, * 1or 2 not work (c = (pmg * per_pos[i]).GetNormalized() * 20)?

@r_gigante @zipit
The detailed explanation is shown below
“up interpolattion”


Try use "spline trail"

I read some papers, but always been very slow, just only expanded know, such as Frenet–Serret formulas etc. But I did not directly find a better way to replace my current method, and I have been looking for it.

Computation of Rotation Minimizing Frames This seems to be a good paper, I will read it carefully.

@m_adam Thank you for your team's reply.
I will share my exploration in this post in the future.

try use GetDirty(DIRTYFLAGS_CACHE)，compare last dirty and current dirty

Hi,
you can read this thread

Thanks for help @a_block , @m_adam . I think the answer to this question is that we can't control the open/close of the group

@m_adam Still can't succeed
In the same Attribute Manager window, for multiple objects with the same UserData, it seems that it is impossible to control the opening or closing of a group alone. If I open (or close) the group of one object, the group corresponding to other objects will also be opened (or closed)

@m_adam Setup succeeded, but the group GUI did not unfold

use python

c4d Use Default Open ,group unfold

c4d not Use Default Open ,but group not fold

@m_adam Thanks for help!

Hi,
in c4d manager UserData dialog can set group Default Open,but i dont how to set fold/unfold in python .
my code:

bc = c4d.GetCustomDataTypeDefault(c4d.DTYPE_GROUP)
bc[c4d.DESC_NAME] = "group_test"
group_did = obj.AddUserData(bc)

bc = c4d.GetCustomDataTypeDefault(c4d.DTYPE_STRING)
bc[c4d.DESC_NAME] = "test"
bc[c4d.DESC_PARENTGROUP] = group_did
did = obj.AddUserData(bc)

Thanks for any help!

Hi.
i want set String UserData interface to multi_line,but in DESC dont find parameter to set.
this is my code:

bc = c4d.GetCustomDataTypeDefault(c4d.DTYPE_STRING)
bc[c4d.DESC_NAME] = "test"
did = obj.AddUserData(bc)

Thanks for any help!

@ferdinand Thanks your reply!

Hi @Cairyn
Thanks for your help, I use method 2 to achieve my goal.
This is a plug-in to mirror a selection of the same / different objects. Thank you for your help again,gif_2 show its work
gif_2

Hi @cairyn ,thanks for your help!
I have made some progress, but there are still some problems!

the image_1 show want wo select 2 edges.
image_1:

Through your reply, it seems that I have got 2 directions to solve my problem. I will show it in the following image_2.
image_2:

use method 2 ,can select the edge show on gif_1.
gif_1:

method 2 code:

import c4d
from c4d import gui


def main():
    if op == None:
        return
    if op.GetType() != c4d.Opolygon:
        return
    
    bs = op.GetEdgeS()
    bs.DeselectAll()
    poly_cnt = op.GetPolygonCount()
    
    sel = bs.GetAll(poly_cnt * 4)
    
    
    edge_list = [(0,1),(0,4)]
    

    for poly_id in range(poly_cnt):
        poly = op.GetPolygon(poly_id)
        for edge in edge_list:
            p1,p2 = edge
            
            edge_index = poly.FindEdge(p1,p2)
            if edge_index != c4d.NOTOK:
                sel[poly_id * 4  + edge_index] = 1
    
    bs.SetAll(sel)
        
    
    c4d.EventAdd()

# Execute main()
if __name__=='__main__':
    main()

Hi,
I know how to select a point / face, but I still don't know how to select an edge. Does each edge have a unique ID? For example, two quadrilateral faces have seven edges. If I choose an edge, I can know that its ID is 6.
I have a picture below. I have marked the edges I want to choose, but I don't know what to do. Can have a simple code demonstration?
Thanks for any help!