khanat-code-old/code/nel/include/nel/3d/bezier_patch.h

136 lines
4 KiB
C++

// NeL - MMORPG Framework <http://dev.ryzom.com/projects/nel/>
// Copyright (C) 2010 Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#ifndef NL_BEZIER_PATCH_H
#define NL_BEZIER_PATCH_H
#include "nel/misc/types_nl.h"
#include "nel/misc/vector.h"
#include "nel/misc/vectord.h"
#include "nel/misc/matrix.h"
namespace NL3D
{
using NLMISC::CVector;
using NLMISC::CVectorD;
using NLMISC::CMatrix;
// ***************************************************************************
/**
* A standard bezier patch of float. (quadpatch only).
* QuadPatch layout (same notations as 3ds Max SDK).
*
*
*
* 0 ---s---> 3
*
* A---> ad ---- da <---D
* | |
* | | |
* | v v
* | ab ia id dc
* t
* | | |
* | | |
* v
* ba ib ic cd
* ^ ^
* | |
* | |
* B---> bc ---- cb <---C
* 1 2
*
* \author Lionel Berenguier
* \author Nevrax France
* \date 2000
*/
class CBezierPatch
{
public:
/// The vertices a,b,c,d of the quad patch.
CVector Vertices[4];
/// The tangents ab, ba, bc, cb, cd, dc, da, ad. NB: tangents are points, not vectors.
CVector Tangents[8];
/// The interiors, ia,ib,ic,id. NB: interiors are points, not vectors.
CVector Interiors[4];
public:
/// Constructor: undefined Bezier patch!!
CBezierPatch() {}
/// complete computation of Vertices, Tangents, and Interiors, providing the vertices and vertex normals.
void make(CVector vertices[4], CVector normals[4]);
/// make default Interiors, according to Vertices and Tangents.
void makeInteriors();
/// Do the matrix transformation m*patch.
void applyMatrix(const CMatrix &m);
/// Evaluate.
CVector eval(float s, float t) const; // s,t coordinates for quad.
/// Evaluate, but return a vector double.
CVectorD evalDouble(double s, double t) const; // s,t coordinates for quad.
/// Evaluate the normal at (s,t). returned vector is normalized.
CVector evalNormal(float s, float t) const; // s,t coordinates for quad.
/// Evaluate the tangentS at (s,t). returned vector is normalized.
CVector evalTangentS(float s, float t) const; // s,t coordinates for quad.
/// Evaluate the tangentT at (s,t). returned vector is normalized.
CVector evalTangentT(float s, float t) const; // s,t coordinates for quad.
/// \name Subdivision.
// @{
/** Subdivide the bezier patch in 2 bezier patches along s, at s (beetween [0,1]).
* NB: left goes from 0 to s, right goes from s to 1.
*/
void subdivideS(CBezierPatch &left, CBezierPatch &right, float s=0.5f) const;
/** Subdivide the bezier patch in 2 bezier patches along t, at t (beetween [0,1]).
* NB: top goes from 0 to t, bottom goes from t to 1.
*/
void subdivideT(CBezierPatch &top, CBezierPatch &bottom, float t=0.5f) const;
// @}
// **********************************
private:
struct CBezierCurve
{
CVector P0, P1, P2, P3;
void subdivide(CBezierCurve &left, CBezierCurve &right, float t);
void set(const CVector &a, const CVector &b, const CVector &c, const CVector &d)
{
P0= a; P1= b; P2= c; P3= d;
}
void get(CVector &a, CVector &b, CVector &c, CVector &d)
{
a= P0; b= P1; c= P2; d= P3;
}
};
};
} // NL3D
#endif // NL_BEZIER_PATCH_H
/* End of bezier_patch.h */