DIRECTORY Complex, Cubic, LSPiece, Seq, Vector, LSSpline;LSSplineImpl: CEDAR PROGRAM IMPORTS LSPiece EXPORTS LSSpline =BEGINHandle: TYPE = LSSpline.Handle;Rec: TYPE = LSSpline.Rec; Create: PUBLIC PROCEDURE [lengthHint: NAT _ 10] RETURNS [handle: Handle] = {handle _ NEW[Rec];handle.z _ NEW[Seq.ComplexSequenceRec[lengthHint]];handle.tan _ NEW[Seq.ComplexSequenceRec[lengthHint]];handle.t _ NEW[Seq.RealSequenceRec[lengthHint]];handle.length _ 0;};Reset: PUBLIC PROCEDURE [handle: Handle] = {handle.length _ 0};Sample: PUBLIC PROCEDURE [handle: Handle, samplePoint, tangent: Complex.Vec _ [0,0]] = {WHILE handle.length >= handle.z.length DOtemp: Handle _ Create[handle.length + handle.length/2 + 1];FOR i:NAT IN [0..handle.length) DOSample[temp, handle.z[i], handle.tan[i]];ENDLOOP;handle^ _ temp^;ENDLOOP;handle.z[handle.length] _ samplePoint;handle.tan[handle.length] _ tangent;handle.length _ handle.length + 1;}; CubicProc: TYPE = PROCEDURE [Cubic.Bezier];Subdivide: PUBLIC PROCEDURE [handle: Handle, cubicProc: CubicProc, tolerance: REAL, from: NAT _ 0, thru: NAT _ LAST[NAT]] = {b: Cubic.Bezier;err: REAL;iterations: NAT;maxDev: REAL;IF handle.length = 0 THEN RETURN;thru _ MIN[thru, handle.length - 1];IF from >= thru THEN RETURN;IF thru = from+1 THEN {b0: Vector.Vec _ handle.z[from];b3: Vector.Vec _ handle.z[thru];cubicProc[[b0, b0, b3, b3]];RETURN;};[b, err, iterations, maxDev] _ LSPiece.FitPiece[z: handle.z,t: handle.t,from: from,thru: thru,maxd: tolerance,maxit: firstTryIterationLimit,initTangent: handle.tan[from],finalTangent: handle.tan[thru]];stats.firstTryCount _ stats.firstTryCount + 1;stats.firstTryIterations _ stats.firstTryIterations + iterations;IF maxDev <= tolerance*firstTryToleranceFactor THEN {[b, err, iterations, maxDev] _ LSPiece.FitPiece[z: handle.z,t: handle.t,from: from,thru: thru,maxd: tolerance/secondTryOptimistFactor,maxit: secondTryIterationLimit,initTangent: handle.tan[from],finalTangent: handle.tan[thru],useOldTValues: TRUE];stats.secondTryCount _ stats.secondTryCount + 1;stats.secondTryIterations _ stats.secondTryIterations + iterations;};IF maxDev <= tolerance THEN cubicProc[b]ELSE {mid: NAT _ (from+thru)/2;Subdivide[handle, cubicProc, tolerance, from, mid];Subdivide[handle, cubicProc, tolerance, mid, thru];}; };firstTryIterationLimit: NAT _ 3;firstTryToleranceFactor: REAL _ 3.0;secondTryIterationLimit: NAT _ 20;secondTryOptimistFactor: REAL _ 2.0;stats: RECORD [firstTryCount: INT _ 0,firstTryIterations: INT _ 0,secondTryCount: INT _ 0,secondTryIterations: INT _ 0];END.    N  LSSplineImpl.mesalast edited by Michael Plass  August 4, 1982 10:19 amÊð  ˜ Jšœ™Jšœ5™5J˜ JšÏk	œ0˜9J˜ Jš	œœœœ	œ˜>Jš˜J˜ Jšœœ˜Jšœœ˜J˜ š
Ïnœœ	œœœ˜LJšœ	œ˜Jšœœ%˜3Jšœœ%˜5Jšœœ"˜0J˜J˜J˜ —Jšžœœ	œ(˜?J˜ šžœœ	œ@˜Xšœ"˜)J˜;šœœœ˜"J˜)Jšœ˜—J˜Jšœ˜—J˜&J˜$J˜"J˜J˜ —Jšž	œœ	œ˜+J˜ šž	œœ	œ3œœœœœ˜}J˜Jšœœ˜
Jšœœ˜Jšœœ˜Jšœœœ˜!Jšœœ˜$Jšœœœ˜šœœ˜J˜ J˜ J˜Jšœ˜J˜—˜0J˜J˜J˜J˜J˜J˜J˜J˜J˜—J˜.J˜Ašœ-œ˜5˜0J˜J˜J˜J˜J˜(J˜J˜J˜Jšœ˜J˜—J˜0J˜CJ˜—Jšœœ˜(šœ˜Jšœœ˜J˜3J˜3J˜—J˜J˜ —Jšœœ˜ Jšœœ˜$Jšœœ˜"Jšœœ˜$J˜ šœœ˜Jšœœ˜Jšœœ˜Jšœœ˜Jšœœ˜J˜J˜ —Jšœ˜J˜ J˜ — …—    
F  „  