76 lines
No EOL
2.8 KiB
C++
76 lines
No EOL
2.8 KiB
C++
//
|
|
// This source code is property of the Computer Graphics and Visualization
|
|
// chair of the TU Dresden. Do not distribute in modified or unmodified form!
|
|
// Copyright (C) 2016 CGV TU Dresden - All Rights Reserved
|
|
//
|
|
/*************************************************************************
|
|
Abstract curve.
|
|
This class provides a basic interface for all curve types. It is
|
|
constructed by passing a reference of a list of control points.
|
|
It corresponds to the mathematical formulation of a curve c(t) via the
|
|
"evaluate" method that returns a certain point as a function of the
|
|
domain parameter "t". The range of "t" can be obtained with the methods
|
|
"get_min_t" and "get_max_t".
|
|
Since every point on a curve is generally the sum of the control
|
|
points weightened with basis functions for every control point
|
|
the interface declares the method "evaluate_basis" as a function
|
|
of the parameter "t" and a control point. Specific curves have to
|
|
implement that method accordingly.
|
|
Because the control points are updated outside of an inherited instance
|
|
of this class the method "control_points_updated" is called after
|
|
every change, addition or removal of a control point.
|
|
The rendering of the curve is not part of this interface but provided
|
|
in another class called "curve_renderer".
|
|
For debugging purpose an additional method called "set_text" is
|
|
provided. Text put into the stream which is passed as a parameter to
|
|
this function will be displayed in the main window.
|
|
**************************************************************************/
|
|
|
|
#pragma once
|
|
|
|
// needed for arbitrary long lists
|
|
#include <vector>
|
|
// needed for the set_text method
|
|
#include <sstream>
|
|
// needed for the data type "point2d"
|
|
#include "tiny_vec.h"
|
|
|
|
|
|
class abstract_curve
|
|
{
|
|
public:
|
|
// Initialize the curve and store a reference of the control points
|
|
abstract_curve(std::vector<point2d> &control_points);
|
|
|
|
virtual ~abstract_curve();
|
|
|
|
// Get the minimum value of the domain
|
|
double get_min_t();
|
|
// Get the maximum value of the domain
|
|
double get_max_t();
|
|
|
|
// Evaluate a curve point as a function of the parameter "t". The
|
|
// range of that function is given by "get_min_t" and "get_max_t"
|
|
virtual point2d evaluate(double t);
|
|
|
|
// Evaluate a basis as a function of a control point and
|
|
// the parameter "t"
|
|
virtual double evaluate_basis(int point_num, double t) = 0;
|
|
|
|
// Shall be called whenever the control point set changes
|
|
virtual void control_points_updated();
|
|
|
|
|
|
// Get a constant list of control points
|
|
const std::vector<point2d>& get_control_points() const;
|
|
|
|
// Put a text into the stream "stream" which will be displayed
|
|
// in the main window
|
|
virtual void set_text(std::stringstream &stream);
|
|
|
|
protected:
|
|
// Range of the domain
|
|
double t_min, t_max;
|
|
// The reference of the control points
|
|
std::vector<point2d> &control_points;
|
|
}; |