Tulip  5.2.0
Large graphs analysis and drawing
GlOpenUniformCubicBSpline.h
1 /*
2  *
3  * This file is part of Tulip (http://tulip.labri.fr)
4  *
5  * Authors: David Auber and the Tulip development Team
6  * from LaBRI, University of Bordeaux
7  *
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15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
16  * See the GNU General Public License for more details.
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19 
20 #ifndef GLUNIFORMCUBICBSPLINE_H_
21 #define GLUNIFORMCUBICBSPLINE_H_
22 
23 #include <tulip/AbstractGlCurve.h>
24 
25 namespace tlp {
26 
27 /**
28  * @ingroup OpenGL
29  * @brief A class to draw open uniform cubic B-splines
30  *
31  * A B-spline is a convenient form for representing complicated, smooth curves. A cubic uniform
32  * B-spline is a
33  * piecewise collection of cubic Bezier curves, connected end to end. A cubic B-spline is C^2
34  * continuous, meaning there is no discontinuities in curvature.
35  * B-splines have local control : parameters of a B-spline only affect a small part of the entire
36  * spline.
37  * A B-spline is qualified as open when it passes through its first and last control points.
38  *
39  */
40 class TLP_GL_SCOPE GlOpenUniformCubicBSpline : public AbstractGlCurve {
41 
42 public:
43  /**
44  * @brief Constructor
45  * @warning Don't use it, see other construstor
46  */
48 
49  /**
50  * @brief GlOpenUniformCubicBSpline constructor
51  *
52  * @param controlPoints a vector of control points (size must be greater or equal to 4)
53  * @param startColor the color at the start of the curve
54  * @param endColor the color at the end of the curve
55  * @param startSize the width at the start of the curve
56  * @param endSize the width at the end of the curve
57  * @param nbCurvePoints the number of curve points to generate
58  */
59  GlOpenUniformCubicBSpline(const std::vector<Coord> &controlPoints, const Color &startColor,
60  const Color &endColor, const float startSize, const float endSize,
61  const unsigned int nbCurvePoints = 200);
62 
63  ~GlOpenUniformCubicBSpline() override;
64 
65  void drawCurve(std::vector<Coord> &controlPoints, const Color &startColor, const Color &endColor,
66  const float startSize, const float endSize,
67  const unsigned int nbCurvePoints = 200) override;
68 
69 protected:
70  void setCurveVertexShaderRenderingSpecificParameters() override;
71 
72  Coord computeCurvePointOnCPU(const std::vector<Coord> &controlPoints, float t) override;
73 
74  void computeCurvePointsOnCPU(const std::vector<Coord> &controlPoints,
75  std::vector<Coord> &curvePoints,
76  unsigned int nbCurvePoints) override;
77 
78 private:
79  unsigned nbKnots;
80  float stepKnots;
81 };
82 }
83 
84 #endif
A class to draw open uniform cubic B-splines.