Questions tagged [spline]

The tag has no usage guidance.

8 questions
Filter by
Sorted by
Tagged with
131 views

How can I determine ideal NURBS surface control points for a multi-patch sphere?

I would like to know how to "parameterize" the control points for the 6 faces of the commonly used NURBS mutli-patch sphere ("Cobb sphere"), for an arbitrary-size control point ...
1 vote
59 views

How do freehand vector drawing tools typically decide where to place the control points?

I'm devising an algorithm to take a freehand curve and make a bezier spline from it. I can do this already just fine, but it's a naive implementation that creates about as many bezier curves as there ...
• 142
1 vote
151 views

Matrix form of an open uniform cubic b-spline

I'm trying to find the matrix form for the equation of a cubic b-spline. More specifically, the "middle" part, S_i(t), is pretty straightforward and available everywhere: ...
• 11
1 vote
185 views

Is there a canonical way to convert G1 continuity to C1 continuity for splines

I understand what C1 and G1 continuity are (e.g. this is not Continuity of parametric and geometric continuity). But let's say I have a list of cubic splines that are, together, G1 continuous. Is ...
70 views

Sweeping cross section along nurbs curve

I have a nurb/b-spline curve in 2d, and I want to sweep a cross section along it. Here is the curve and resulting "tube" (green points are control points): However, as you can see, the ...
• 133
218 views

How to decide granularity for sampling a bezier curve for rendetion

If I want to draw a cubic bezier curve, I need to sample points on it and draw the resulting poly lines. One could sample the curve using De Casteljau algorithm and incrementing $t$ from 0 to 1 with a ...
• 516
795 views

Rendering splines on GPU

We have an application which needs to render spline curves (cubic, bezier, b-spline etc.). We currently have working algorithms in C to stroke the control points of these curves into line strips. The ...
• 153
212 views

Cubic Splines - Do Parametric and Explicit representation give different curves?

I asked a similar question here before but since the previous post original question was different, I think it was confusing people. So I've voted to close that and asking the new question here. I'm ...
• 2,438