Defines one or more concatenated bicubic Bézier patches to be used with the BezierSurface class. More...

#include <BezierSurface.hpp>

Inheritance diagram for vl::BezierPatch:

Public Types
typedef std::vector< vec3 >	Points
	The control points grid defining the bicubic Bézier patch(es).
Public Member Functions
	BezierPatch ()
	Constructor.
	BezierPatch (int x, int y)
	Constructor.
void	resize (int x, int y)
	Defines the x and y dimensions of the control point grid defining the patch.
int	x () const
	Returns the `x` dimension of the patch as specified by resize().
int	y () const
	Returns the `y` dimension of the patch as specified by resize().
Points &	points ()
	The control points grid defining the bicubic Bézier patch(es).
const Points &	points () const
	The control points grid defining the bicubic Bézier patch(es).
vec3 &	at (int i, int j)
	Returns the i/j control point.
const vec3 &	at (int i, int j) const
	Returns the i/j control point.
Protected Attributes
Points	mControlPoints
int	mX
int	mY

Detailed Description

Defines one or more concatenated bicubic Bézier patches to be used with the BezierSurface class.

Member Typedef Documentation

typedef std::vector< vec3 > vl::BezierPatch::Points

The control points grid defining the bicubic Bézier patch(es).

Definition at line 50 of file BezierSurface.hpp.

Constructor & Destructor Documentation

vl::BezierPatch::BezierPatch ( ) [inline]

Constructor.

Definition at line 52 of file BezierSurface.hpp.

References VL_DEBUG_SET_OBJECT_NAME.

vl::BezierPatch::BezierPatch	(	int	x,
		int	y
	)		`[inline]`

Constructor.

Definition at line 57 of file BezierSurface.hpp.

References VL_DEBUG_SET_OBJECT_NAME.

Member Function Documentation

void BezierPatch::resize	(	int	x,
		int	y
	)

Defines the x and y dimensions of the control point grid defining the patch.

The x and y parameters must be of the form 3*n+1 with n integer positive, i.e 4 (n=1), 7 (n=2), 10 (n=3) and so on.

- The simplest bicubic Bézier patch requires 4x4 = 16 control points: A, B, C, D, E, F, G, H, I, L, M, N, O, P, Q, R
- The Bézier surface is guaranteed to touch only the 4 corner control points A, D, O and R.

A---B---C---D
|   |   |   |
E---F---G---H
|   |   |   |
I---L---M---N
|   |   |   |
O---P---Q---R

In this case we would call "resize(4,4)"

- You can concatenate two bicubic Bézier patches to form a larger suface by sharing their control points like this:

   patch 1     patch 2
A---+---+---B---+---+---G
|   |   |   |   |   |   |
+---+---+---C---+---+---+
|   |   |   |   |   |   |
+---+---+---D---+---+---+
|   |   |   |   |   |   |
F---+---+---E---+---+---H

In this case we would call "resize(7,4)"

- In this case the two patches share the control points B, C, D and E.
- As we can see the total control points needed are 28 = (2 (patches along x) * 3 + 1) * (1 (patches along y) * 3 + 1)
- Also in this case the Bézier surface is guaranteed to touch only the 6 corner control points A, B, E, F, G and H.

Definition at line 70 of file BezierSurface.cpp.

References vl::Log::error(), mControlPoints, mX, mY, VL_CHECK, x(), and y().

int vl::BezierPatch::x ( ) const [inline]

Returns the x dimension of the patch as specified by resize().

Definition at line 66 of file BezierSurface.hpp.

Referenced by resize(), and vl::BezierSurface::updateBezierSurface().

int vl::BezierPatch::y ( ) const [inline]

Returns the y dimension of the patch as specified by resize().

Definition at line 68 of file BezierSurface.hpp.

Referenced by resize(), and vl::BezierSurface::updateBezierSurface().

Points& vl::BezierPatch::points ( ) [inline]

The control points grid defining the bicubic Bézier patch(es).