Blender Stack Exchange is a question and answer site for people who use Blender to create 3D graphics, animations, or games. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

What mathematical formula does Blender use to calculate Bezier paths?

share|improve this question

For each segment of the path between two control points, it approximates a cubic Bezier curve:

enter image description here

where P_0 and P_3 are the control points and P_1 and P_2 are the handles.

enter image description here

share|improve this answer

Even though this isn't a question about Blender's code exactly, linking to Blender's code for calculating cubic bezier curves may help understanding.

  • 2D masks can also use a different (more straightforward but slower) method where you can get any point on along the spline using a factor:
    See BKE_mask_point_segment_co (trivial to adapt for 3D curves too).
  • 3D curves use an optimized (less straightforward), fixed step, subdivision method:
    See BKE_curve_forward_diff_bezier

To see how this method works, see wikipedia's description of Higher order curves

share|improve this answer
I read that bezier curves commonly are interpolated with Casteljau's algorithm. – pink vertex Feb 2 '14 at 10:38

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.