Question by calabi · Jun 10, 2020 at 06:23 PM · movement speed bezier constant

How to move object along Spline at constant speed?

So I'm trying to move something along a spline at a constant, as objects speed up and slow down at specific points on the spline if I move them normally. I've managed to glean some information and got partway there. I have couple of methods where I can reasonably calculate the length of two points on the spline and another method where I can calculate a consistent. I can use these to place objects at consistent equidistant points on the spline but I cant quite figure out how to use them to move objects along the spline at a consistent which is frame rate independent. Here's an example of the code I can use to place objects along the spline at consistent points and it works.

 for (int i = 0; i <= numofpoints; i++)
         {
             Entity curent = EntityManager.Instantiate(Prefabinator.TestIntervalPrefab);
 
             currbezpos = calcBezier.Execute(ref currentBezier, curensplinepos);
 
             EntityManager.SetComponentData(curent, new Translation { Value = currbezpos });
 
             EntityManager.SetName(curent, "Thepointsonspline");
 
             curensplinepos = calcdistomove.Execute(ref currentBezier, 2.5f, curensplinepos);  
        
         }

Basically calcdistomove gets the current place on the spline and a specified distance and then returns the place on the spline at that distance from the original place on the spline. I guess I don't really understand how to use it. I've tried lots of different ways of moving things but none seem to give consistent result. Current example below that doesn't work.

  var tempval = calcdistomove.Execute(ref currentBezier, 1.0f, placeonSpline.floatVal);
             placeonSpline.floatVal = tempval;
 
             var tempee = calcBezier.Execute(ref currentBezier, placeonSpline.floatVal);
 
             moventity.Value = tempee;

Any help would be appreciated.

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