GEO/GEO_PrimRBezCurve.h

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/*
 * PROPRIETARY INFORMATION.  This software is proprietary to
 * Side Effects Software Inc., and is not to be reproduced,
 * transmitted, or disclosed in any way without written permission.
 *
 * Produced by:
 *      Cristin Barghiel
 *      Side Effects Software Inc.
 *      20 Maud St.
 *      Toronto, Ontario,  M5V 2M5
 *      Canada
 *      416-366-4607
 *
 * NAME:        Geometry Library (C++)
 *
 * COMMENTS:
 *      This class implements a piecewise Bezier curve defined by 
 *      a set of breakpoints, basis function, and CVs.
 *
 * 
 */

#ifndef __GEO_PrimRBezCurve_h__
#define __GEO_PrimRBezCurve_h__

#include "GEO_API.h"
#include "GEO_Curve.h"
#include "GEO_PrimType.h"

class UT_Vector4;

class GEO_API GEO_PrimRBezCurve : public GEO_Curve {
public:
    // Constructor that attaches this curve to detail "d". You can optionally
    // specify the number of vertices.
    GEO_PrimRBezCurve(GEO_Detail *d, unsigned int m=0)
    : GEO_Curve(d, (int)m) {}

    // Trivial class destructor, virtual by inheritance. Please read the 
    // comments on the parent class d-tor.
    ~GEO_PrimRBezCurve();

    // Given a domain value (u), store all the basis derivatives (from 0 to du
    // inclusive) into bmatx. Return the min index of the CVs needed
    // for the linear combination. The indices may exceed the number of
    // vertices if the curve is wrapped, so remember to use % getVertexCount().
    virtual int         evaluateBasisDerivs(float u,float bmatx[][GB_MAXORDER],
                                            int &cvoffset, unsigned du = 0,
                                            int uoffset = -1) const;

    // Evaluate the basis at the given point in the domain and also return
    // the index of the first CV to linearly combine the basis with. The CV
    // index may exceed the number of vertices if the curve is wrapped,
    // so remember to use modulus (%). This method handles both rational and
    // non-rational curves.
    virtual int         evaluateBasis(float u,float *ubvals, int &cvoffset,
                                      unsigned du=0, int uoffset=-1) const;

    // Two flavours of a bulk curve evaluator that computes points or
    // derivatives inside a parametric interval determined by:
    // a) the u value specified in uArr. The length of the parameter array is
    // arrLen. b) uStart and uStop.
    // The functions return  0 if successful, and -1 otherwise.
    virtual int         evaluateSegm(float *uArr, unsigned uArrLen, 
                                     UT_Vector4 *pos, unsigned du=0) const;
    virtual bool        evaluateSegm(float uStart, float uStop, 
                                     unsigned nu, GEO_Vertex **results,
                                     GEO_AttributeHandleList &hlist,
                                     unsigned du=0) const;
    virtual int         evaluateSegm(float uStart, float uStop, unsigned nu,
                                     UT_Vector4 *pos, unsigned du=0) const;
    virtual int         evaluateSegmWAttrib(float uStart, float uStop, 
                                     unsigned nu, UT_Vector4 *pos,
                                     GB_AttributeData *adata,
                                     const GB_FloatOffsets &foffsets,
                                     unsigned du=0) const;

    // Compute the location of the breakpoint. Return 0 if OK, else -1.
    virtual int         evaluateBreakpoint(int uidx, UT_Vector4 &pos,
                                           int du = 0) const;

    // Another pair of curve evaluators. These take a start and a stop index
    // in the valid knot domain and an lod representing number of points to
    // be interpolated between every two breakpoints. The methods ALWAYS
    // interpolate the encountered breakpoints (aka "edit points"). They return
    // the number of points in the list or -1 if unsuccessful. Please save
    // yourself headaches and pass VALID start and end indices (see the
    // method validInterval() in GB_Basis).
    virtual int         evaluateBreakSegm(int uStartIdx, int uStopIdx, int lod,
                                     GEO_Vertex **results,
                                     GEO_AttributeHandleList &hlist,
                                     unsigned du=0) const;
    virtual int         evaluateBreakSegm(int uStartIdx, int uStopIdx, int lod,
                                     UT_Vector4 *pos, unsigned du=0) const;
    virtual int         evaluateBreakSegmWAttrib(int uStartIdx, int uStopIdx,
                                     int lod, UT_Vector4 *pos,
                                     GB_AttributeData *adata,
                                     const GB_FloatOffsets &foffsets,
                                     unsigned du=0) const;

    //  Remove all repeated vertices - (only gets consecutive vertices)
    virtual int          removeRepeatedVertices(int check_order = 0);

    // compute the un-normalized lengths corresponding to points on the curve
    // evaluated at the valid knots parameter values
    // (ones with which lie within curve paramer domain) and store them
    // in the 'lengths' array. Returns the curve "length" (same as last knot).
    // The meaning of "length" depends on ptype, and can mean chord length,
    // square chord length, approximate arc length.
    virtual float       getKnotLengths(GB_ParmType ptype, 
                                       UT_FloatArray &lengths) const;

    // Evaluate the curve over the valid parametric interval, and place the
    // points in the pos array. Return 0 if successful, and -1 otherwise.
    virtual int         fillCurve(int nu, UT_Vector4 *pos) const;

    // Given a CV index figure out the min/max indicies of the knots between
    // which the curve needs to be re-evaluated if the CV changes. If not
    // given a valid CV index, the method returns -1. Otherwise it returns 0.
    // If the curve wraps the domain we return will be rather large.
    virtual int         domainRangeOfCV(int cvidx, int &mink,int &maxk) const;

    // Given a CV index figure out the min/max breakpoints which are
    // affected if the CV changes.  If not given a valid CV index, the
    // method returns -1.  Otherwise it returns 0.  Also returns -1 if
    // no breakpoints are affected.
    // NOTE: use % breakCount since maxbkp may be >= breakCount
    virtual int         breakpointRangeOfCV(int cvidx, int &minbkp,
                                            int &maxbkp) const;

    // Reparameterize the curve by changing its basis. The first breakpoint
    // remains unchanged.
    virtual void        reparameterize(GB_ParmType ptype);

    // Notify whomever needs to know that we have changed the weight or the
    // coordinates of cv[r].
    virtual int         recordChange(unsigned r);

    // Set the closed or open flag, and make sure the basis knot vector is
    // consistent with the change. These functions are virtual by inheritance.
    // They change the number of CVs, so use them with care. Also, they do
    // not keep a history of changes: if you start with a closed curve
    // and then you open and close it again, the re-closed curve uses 
    // 'degree-2' new CVs that have been generated for this purpose.

    // Close up an open curve.
    //
    // If preserveShape = 1:
    //          add extra cvs at the end to define the last span.
    //          if rounded, 
    //                  the new cvs just added will be arranged to 
    //                  give a rounded appearance.
    //          else
    //                  the new cvs just added will form a straight 
    //                  line between the first and last endpoint.
    // If preserveShape = 0:
    //          just grow the basis by one span, without adding any new cvs.
    //          ignore the rounded flag.
    virtual void        close(int rounded = 1, int preserveShape = 0);

    // Open up a closed curve.
    //
    // If preserveShape = 1:
    //          the open curve will have exactly the same geometry
    //          (ie. still look closed) with the first point duplicated.
    // If preserveShape = 0:
    //          the open curve will remove the last span in the basis, 
    //          thus open up a gap in the curve. 
    //          last few cvs are dangling which do not form a valid 
    //          curve segment, if the safe flag = 0. 
    // The safe flag is to remove unneed cvs for ensuring the resulting
    // curve is a valid bezier curve.
    virtual void        open(int preserveShape = 0, int safe = 0);

    // Insert or delete vertices. The insertion methods return the index if
    // successful and -1 otherwise. The deletion methods return 0 if ok and
    // -1 otherwise. The insertion methods create the point if it does not
    // exist.
    virtual int         insertVertex(GEO_Point  *ppt=0, unsigned int where=0);
    virtual int         appendVertex(GEO_Point  *ppt=0);
    virtual int         deleteVertex(GEO_Vertex &vtx);
    virtual int         deleteVertex(unsigned int num);

    // Delete the vertex that uses the point.
    virtual int         ifDetachPoint(GB_Element  *ppt) const;

    // Assuming the curve is closed, "unroll" it so that the CVs that are
    // shared to form a wrapped curve are made unique. Also, the curve becomes
    // open. The base class method only flips the open flag. If the curve is
    // not closed, the method returns -1. Otherwise it returns 0.
    virtual int         unroll(int append_pts = 1);

    // Raise the number of CVs to match the newcount. The shape of the curve
    // (especially if parametric) should NOT change. Return 0 upon success
    // and -1 otherwise.  start and stop define which indices to examine
    // if newcount is negative it is taken as a relative value.
    virtual int         loft(int newcount, int start=-1, int stop=-1);


    // Insert a breakpoint at the given point in the domain and return its 
    // index if successful. Return -1 in case of failure (eg. if outside the 
    // valid domain or equal to an existing breakpoint).
    virtual int         refine(float k, GEO_AttributeHandleList &hlist, int=0);
    virtual int         refine       (float k, int=0);
    virtual int         refineWAttrib(float k, const GB_FloatOffsets &foffsets,
                                      int=0);

    // Increase the order. Return 0 if successful, -1 otherwise (eg.
    // order cannot be increased because it's >= MAXORDER).
    virtual int          raiseOrder(int neworder, GEO_AttributeHandleList &hl);
    virtual int          raiseOrder       (int neworder);
    virtual int          raiseOrderWAttrib(int neworder,
                                           const GB_FloatOffsets &foffsets);

    // Warp the curve at u by the given delta. Change 1 or 2 Cvs and possibly
    // insert a knot once or more as well. If a knot is inserted or we happen
    // to land exactly on a knot, we change only one CV. The bias makes sense
    // only when changing 2 CVs, and will be ignored altogether if < 0.
    // We return the index of the affected knot in the sequence, or -1 if
    // there's an error.
    virtual int          warp(float u, const UT_Vector3 &delta,
                              GEO_AttributeHandleList &hlist,
                              float sharpness = 0.0f, float bias = -1.0f);
    virtual int          warp(float u, const UT_Vector3 &delta,
                              GB_FloatOffsets *foffsets = 0,
                              float sharpness = 0.0f, float bias = -1.0f);

    // Translate the CVs such that the given breakpoint change positions by
    // the given delta.  Return -1 if something goes wrong, 0 if translation
    // was successful.
    // NOTE: uindices cannot contain any duplicates.  If the curve is closed,
    //       the first and last breakpoint are considered the same.
    virtual int          translateBreakpoints(const UT_IntArray &uindices,
                                              const UT_Vector3 &delta,
                                              int fixbkpts = 1,
                                              GB_PointGroup *ptgroup = NULL,
                                              GEO_Delta *geodelta = 0);

    virtual int          transformBreakpoints(const UT_IntArray &uindices,
                                              const UT_Matrix4 &matx,
                                              int fixbkpts = 1,
                                              GB_PointGroup *ptgroup = NULL,
                                              GEO_Delta *geodelta = 0);

    // Append another face to us in one of two ways: blend the two endpoints
    // or connect them straight or rounded. The bias ranges from 0 to 1 and is
    // relevant only to blending. The tolerance for blending: if 0, the two
    // endpoints will merge into one point with a discontinuity; if less than
    // 1, we insert knots into the curves to minimize the affected areas; if 1,
    // no refinement is done. For the non-blend case, the tolerance will
    // generate a span whose shape goes from round to straight; 0 tolerance
    // means straight connection.  We return 0 if OK and -1 if error. Both
    // curves must be open and have the same order.
    virtual int          attach(const GEO_Face &face, int blend = 1,
                               float bias = .5f, float tolerance = 1.f, int=0,
                               GB_PointGroup *ptgroup=0);

    // Build a planar (domain) face of the same type as us and with the same
    // number of vertices. Copying the (x,y) values of our points to the planar
    // face is optional.
    virtual GD_Face     *planar(GD_Detail &dgdp, int copyxy = 0) const;

    // Query the primitive type. The function is virtual by inheritance.
    virtual unsigned     getPrimitiveId(void) const;

    // reverse the vertices of the curve, preserving shape
    virtual void         reverse(void);

    // If ustart and ustop are two values in the valid interval,ustart < ustop,
    // return the part of curve defined by ustart and ustop in a new primitive.
    // Return 0 if a problem is encountered.
    virtual GEO_Curve   *extract(float ustart,float ustop) const;

protected:
    // Get a new basis of a type that matches our type:
    virtual GB_Basis    *newBasis(void) const;

    // Two different closing methods:
    void                 closeSharp(void);
    void                 closeRounded(void);

    // increase order by 1.
    void                 incrementOrder(GEO_AttributeHandleList &hlist);
    void                 incrementOrder(void);
    void                 incrementOrderWAttrib(const GB_FloatOffsets &foffsets);

private:
    // Nothing.
};
#endif

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