Posts made by happygrass_cn

Hi, I am making a DEMO for my research work of crowd simulation. The people may walk and stop during the animation. The position and drection(Velocity) of the crowd have been recorded in a text file. I have written a Python script successfully read the data file at each keyframe. Now, I use TP partilce to animate the crowd. And, I subsitute the particle with a Man model through XPresso Pshape tags. Shown as followed.

When the position is not changed the model's motion should stop(stay at present keyframe) untill he moved again. The motion of the model is pre-rendered like a re-cycle movie.

The keyframe of the Model as follow:

What should I do to hold on the present keyframe? Sorry ablout my poor question description!

My Python scripts as followed:

# Boids for Py4D by smart-page.net

import c4d
import math

# particles' params
boids_number = 1000
currentframe = None

# used for read user data frame by frame
frame_step = boids_number+1 
frame_total = 0


def main():
    global tp
    global doc
    global currentframe    
    
    currentframe = doc.GetTime().GetFrame(doc.GetFps())
    
    # particles born at 0 frame
    if currentframe == 0:   
        tp.FreeAllParticles()
        tp.AllocParticles(boids_number)
             
                
    # life time for particles
    lt = c4d.BaseTime(1000)

    # user data for paritlces
    filename = op[c4d.ID_USERDATA, 1]
   
    # open the user file. First, read a frame of data from the user file. Then, read lines one bye one to feed the particles.
    with open(filename, 'r') as fn:
        
        # read all lines of the user data
        lines = fn.readlines()
        
        # compute how many frames of data in the file
        frame_total = int(len(lines) / frame_step)
        
        # 
        frame = 1
        i=0

        #read a frame of data according to the scene keyframe
        for frame in range(frame_total): 
            if frame == currentframe:
                t_lines = lines[frame * frame_step:frame * frame_step + frame_step - 1]  
                
                #pase lines of the readed data 
                for line in t_lines: 
                    if line == t_lines[0]:  # filter the first line of each frame in the text file, because is just flag words
                        print(line)                       

                    else:
                        #split position(x,y,z) and direction (dx,dy,dz)
                        x, y, z, dx, dy, dz = line.split()                      
                        pos = c4d.Vector(float(x), float(y), float(z) )
                        vol = c4d.Vector(float(dx), float(dy), float(dz))
                                               
                        temp=(pos-tp.Position(i)).GetLength()  
                        
                        # some codes wanted here
                        if temp==0.0:
                            # the motion of the man should stop.
                            # should I  edit the keyframe of the walking Man model?
                            # when temp==0, then the walking Man stay at present keyframe but not go ahead along with the scene keyframe. 
                                               
                                             
                        
                       
                        # align to velocity direction
                        vel = vol.GetNormalized()
                        side = c4d.Vector(c4d.Vector(0, 1, 0).Cross(vel)).GetNormalized()
                        up = vel.Cross(side)
                        m = c4d.Matrix(c4d.Vector(0), side, up, vel)
                        tp.SetAlignment(i, m)
                       
                        # set position
                        tp.SetPosition(i,pos)
                        
                        # set life time for particle i
                        tp.SetLife(i, lt)  
                         
                        i=i+1

    c4d.EventAdd()

if __name__=='__main__':
    main()
code_text

My user data format as followed.