B-splines

版本 1.5.0.1 (19.7 KB) 作者: Levente Hunyadi
Draw, manipulate and reconstruct B-splines.
14.7K 次下载
更新时间 2021/2/18

查看许可证

The package comprises of a graphical utility to place uniform B-spline control points and see how the B-spline is redrawn as control points or control point weights are adjusted, and functions to estimate B-splines with known knot vector, given a set of noisy data points either with known or unknown associated parameter values.

As regards the interactive interface, the user is shown a figure window with axes in which to choose control points of a uniform B-spline. As points are placed in the axes, the B-spline of specified order is drawn progressively. The user may terminate adding control points by pressing ENTER or ESC, or may place the last control point with a right mouse button click.

Once done, control points may be adjusted with drag-and-drop. Hold down the left mouse button over any control point and drag it to another location. Control point adjustment works in 3D; use the rotation tool to set a different camera position. It is also possible to explicitly set the x, y and z coordinates as well as the weight of a control point: click on the point, enter new values and hit ENTER.

As regards the non-interactive interface, functions include calculating and drawing basis functions, computing points of a (weighted or unweighted) B-spline curve with de Boor's algorithm, and estimating B-spline control points given noisy data, either with or without parameter values associated with the observed data points.

From a programmers' perspective, this example illustrates how to use nested functions to extend variable scope, implement drag-and-drop operations, combine normalized and pixel units for control docking and register multiple callbacks for a single event in an interactive user interface.

USAGE

The simplest way to get started is to run "bspline_gui", which activates the figure window to place B-spline control points interactively. Examples are bundled to illustrate various B-spline curve computation and approximation methods.

MATLAB 版本兼容性
创建方式 R2008a
兼容任何版本
平台兼容性
Windows macOS Linux
类别
Help CenterMATLAB Answers 中查找有关 Splines 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!
版本 已发布 发行说明
1.5.0.1

Updated to R2020b

1.5.0.0

Fixed an issue with the last element in the knot vector (reported by Jolyn Loo).

1.4.0.0

Added computing knot vector and control points associated with derivative of B-spline curve (contributed by Joe Hays).

1.3.0.0

Added estimation without known B-spline curve parameter values.

1.2.0.0

Added control point weights and control point approximation from data.

1.0.0.0