Bézier & de Casteljau

This interactive simulator explores Bézier & de Casteljau in Math Visualization. Drag control points; live recursive linear-interpolation scaffolding evaluates B(t). Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.

Who it's for: Suited to beginners and first exposure to the topic. Typical context: Math Visualization.

Key terms

  • zier
  • casteljau
  • bezier de casteljau
  • math
  • visualization

How it works

**Bézier curves** are everywhere in graphics, fonts and CAD. The **de Casteljau algorithm** evaluates **B(t)** by **repeated linear interpolation**: take each pair of adjacent control points, slide a fraction *t* along the segment, and you get a new — shorter — control polygon. Iterate until a single point remains. It is **numerically stable**, geometric, and reveals beautiful **scaffolding** — drag any **Pᵢ** to reshape the curve in real time.

Key equations

B(t) = Σᵢ C(n,i) (1−t)ⁿ⁻ⁱ tⁱ Pᵢ
de Casteljau: Pᵢ⁾ʳ⁾ = (1−t)Pᵢ⁾ʳ⁻¹⁾ + t Pᵢ₊₁⁾ʳ⁻¹⁾
B(t) = P₀⁾ⁿ⁾, cost: O(n²)