SampledCurves.mesa

DIRECTORY

SampledCurves: CEDAR DEFINITIONS = {

SampledCurve: TYPE = REF SampledCurveRec;

PointRec: TYPE = RECORD [p, t: Vector.VEC, k,ds: REAL];

SampledCurveRec: TYPE = RECORD[closed: BOOLEAN, element: SEQUENCE length:NAT OF PointRec];

SampledCurveFromSamples: PROC [samples: Seq.ComplexSequence, closed: BOOLEAN] RETURNS[SampledCurve];

DeltaK: PROC[sc: SampledCurve] RETURNS [deltas: Seq.RealSequence];

Wrap takes an index and returns the newIndex MOD curve length if the curve is closed, does the end test and raises OpenCurve if the curve is open.

Wrap: PROC[sc: SampledCurve, index: INT] RETURNS [newIndex: NAT];

OpenCurve: SIGNAL; --raised when you try an illegal operation on an open curve

ArcLength: PROC[sc: SampledCurve, from, to: NAT] RETURNS[d: REAL];

This finds a sequence of TRUE values as defined by the ConditionProc.

ft is the index of the first TRUE value, lt is the index of the last TRUE value

Uses unwrapped values ie. start, ft, lt can be outside the range [0..bool.length)

ConditionProc: TYPE = PROC[point: PointRec] RETURNS[BOOLEAN];

None: SIGNAL;

FindSequence: PROC[sc: SampledCurve, start: NAT, condition: ConditionProc] RETURNS[ft, lt: NAT];

Some procedures for computing curvature.

There are two methods:

CurvatureProc: TYPE = PROC[dIn,dOut: Vector.VEC] RETURNS [REAL];

SetKProc: PROC[CurvatureProc];

DThetaDegrees: CurvatureProc;

DThetaRadians: CurvatureProc;

CircleCenter: CurvatureProc;

FindCircleCenter: PROC[p0,p1,p2: Vector.VEC] RETURNS [center: Vector.VEC, valid: BOOLEAN];

FindAngleDegrees: PROC[dIn,dOut: Vector.VEC] RETURNS [REAL];

}.