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

@r_gigante Thanks for your help!

@Cairyn
It seems I should try some other solutions.Thanks for your help.

@Cairyn
Thanks,useful!
Is there a way to directly obtain the object using this uniquely identified ID?

Hi,
If there are multiple objects with the same name and the same type in the object manager, what is the unique identification of each object.
Thanks for any help!

my python plugins(draw some point in spline) work in R21 and R22 have different result in viewport

in Right/Top/Front view use code

bd.SetMatrix_Camera()
offset = c4d.Vector(0.0,0.0,-100000.0)
new_point = bd.WC(test_pointone) + offset
s = bd.WC(test_pointone) + offset
e = bd.WCtest_pointtwo) + offset

so i change code for R22

bd.SetMatrix_Camera()
offset = c4d.Vector(0.0,0.0,-100000.0)
in_v = c4d.Vector(1.0,-1.0,1.0)
new_point = (bd.WC(test_pointone) + offset) ^ in_v
s = (bd.WC(test_pointone) + offset) ^ in_v
e = (bd.WCtest_pointtwo) + offset) ^ in_v

R22 Change Something?
Thanks for any help!

@zipit Thanks,this paper Parallel Transport Approach to Curve Framing
I will follow your suggestion to explore RMF. It may be that the language barrier prevents us from communicating well, but I still get a lot of help from your answer. I use Google translate

@zipit Hi, I came back a bit late.
I read the paper and watched the video. The video is understandable and the paper is still obscure. The effect of Parallel Transport is similar to some functions of c4d python utils.SplineHelp ().
The Parallel Transport method is useful, but using the control object to control the rotation of the joint (rotate around z) is still a bit unclear (in the picture below). The paper seems to mention some solutions such as (Animating rotation with quaternion curves) and (Fiber bundle twist reduction.)

@zipit Thank you for your patient reply, it really helped me a lot. I need to learn about PTF,This is a new point of knowledge for me, and I need some time to understand how it works. I will update the progress of the solution here.
Yes,rotation is banking ,in my method it points to the next object in the chain of objects，not use tangent

@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_magalhaes
ok,It's a bit complicated