failing to access CTracks

On 29/03/2013 at 06:16, xxxxxxxx wrote:

User Information:
Cinema 4D Version:   14.034 
Platform:   Windows  ;   
Language(s) :     C++  ;


I am writing an exporter in C++ and cannot get any CTracks from my animated objects.
Here is the simple code:

BaseObject* op = doc->GetFirstObject();
CTrack* track = op->GetFirstCTrack();

while (track)
  GePrint( "found track: " + track->GetName() );
  track = track->GetNext();

GetFirstCTrack() never returns a CTrack object.

I am new to the C++ SDK but I have managed to export static transformations, polygons, uvs etc.

Is there a plugin or function inside of Cinema 4D to get detailed SDK data structure information for debugging purposes?

Thanks for any help.

On 29/03/2013 at 07:58, xxxxxxxx wrote:

It looks like you might not be going deep enough.
Keys reside on curves, which reside in tracks.
So to get at a key value you need to go through the track->curve->key tree branching system.


//This code Get's the key values on all the tracks of an object   
  BaseObject* obj = doc->GetActiveObject();      //Get the active object  
  if(!obj) return False;  
  BaseTime time = doc->GetTime();               //Assigns the basetime class to a variable  
  Real fps = doc->GetFps();                     //Gets the frames per second value  
  Real currentFrame = time.GetFrame(fps);       //The current frame the slider is on  
  CTrack *trk = obj->GetFirstCTrack();          //Get the first track  
      CCurve *curve = trk->GetCurve(CCURVE_CURVE, FALSE); //Get the curve on the first track  
      Real i;  
      for(i=0; i<curve->GetKeyCount(); i++)   
          CKey *keys = curve->GetKey(i);                   //Get all of the keys  
      Real keyframe = keys->GetTime().GetFrame(fps);   //Assing the frame the keys are on to this variable  
      float keyvalues = keys->GetValue();              // Get the values of each key   
      GePrint("Frame= "+ RealToString(keyframe) + "  " + "   " + "Values= " + RealToString(keyvalues));     
      trk = trk->GetNext();  


On 29/03/2013 at 08:50, xxxxxxxx wrote:

Thanks for the code ScottA,

I didn't even get to CCurve and CKey yet because my problem is getting anything but NULL from:

CTrack \*trk = obj->GetFirstCTrack();

On 30/03/2013 at 17:35, xxxxxxxx wrote:

Trying the same in python gives me the expected CTrack names and subsequent data, so I know I actually have animated data...

import c4d  
def main() :  
  obj = doc.GetFirstObject()  
  while obj != None:  
      print "tracks found for '" + obj.GetName() + ":"  
      track = obj.GetFirstCTrack()  
      while track != None:  
          print track.GetName()  
          curve = track.GetCurve()  
          while idx < curve.GetKeyCount() :  
              key = curve.GetKey(idx)  
              time = key.GetTime()  
              print str( time.GetFrame(doc.GetFps()) ) + ": " + str(key.GetValue())  
          track = track.GetNext()  
      obj = obj.GetNext()  

On 01/04/2013 at 04:35, xxxxxxxx wrote:

Found the error on my part:

I created a clone of my document:


which defaults to not cloning any animations.

doc->Polygonize( true );

Does the trick.