Files
OpenNest/OpenNest.Engine/Fill/StripeFiller.cs

301 lines
9.8 KiB
C#

using System.Collections.Generic;
using System.Linq;
using System.Threading;
using OpenNest.Engine.BestFit;
using OpenNest.Engine.Strategies;
using OpenNest.Geometry;
using OpenNest.Math;
using System.Diagnostics;
namespace OpenNest.Engine.Fill;
public class StripeFiller
{
private const int MaxPairCandidates = 5;
private const int MaxConvergenceIterations = 20;
private const int AngleSamples = 36;
private readonly FillContext _context;
private readonly NestDirection _primaryAxis;
public StripeFiller(FillContext context, NestDirection primaryAxis)
{
_context = context;
_primaryAxis = primaryAxis;
}
public List<Part> Fill()
{
var bestFits = GetPairCandidates();
if (bestFits.Count == 0)
return new List<Part>();
var workArea = _context.WorkArea;
var spacing = _context.Plate.PartSpacing;
var drawing = _context.Item.Drawing;
var perpAxis = _primaryAxis == NestDirection.Horizontal
? NestDirection.Vertical
: NestDirection.Horizontal;
var sheetSpan = GetDimension(workArea, _primaryAxis);
var strategyName = _primaryAxis == NestDirection.Horizontal ? "Row" : "Column";
List<Part> bestParts = null;
var bestScore = default(FillScore);
for (var i = 0; i < bestFits.Count; i++)
{
_context.Token.ThrowIfCancellationRequested();
var candidate = bestFits[i];
var pairParts = candidate.BuildParts(drawing);
var (angle, waste, count) = ConvergeStripeAngle(
pairParts, sheetSpan, spacing, _primaryAxis, _context.Token);
if (count <= 0)
continue;
var rotatedPattern = FillHelpers.BuildRotatedPattern(pairParts, angle);
var perpDim = GetDimension(rotatedPattern.BoundingBox, perpAxis);
var stripeBox = MakeStripeBox(workArea, perpDim, _primaryAxis);
var stripeEngine = new FillLinear(stripeBox, spacing);
var stripeParts = stripeEngine.Fill(rotatedPattern, _primaryAxis);
if (stripeParts == null || stripeParts.Count == 0)
continue;
var stripePattern = new Pattern();
stripePattern.Parts.AddRange(stripeParts);
stripePattern.UpdateBounds();
var gridEngine = new FillLinear(workArea, spacing);
var gridParts = gridEngine.Fill(stripePattern, perpAxis);
if (gridParts == null || gridParts.Count == 0)
continue;
var allParts = new List<Part>(gridParts);
var remnantParts = FillRemnant(gridParts, drawing, angle, workArea, spacing);
if (remnantParts != null)
allParts.AddRange(remnantParts);
var score = FillScore.Compute(allParts, workArea);
if (bestParts == null || score > bestScore)
{
bestParts = allParts;
bestScore = score;
}
NestEngineBase.ReportProgress(_context.Progress, NestPhase.Custom,
_context.PlateNumber, bestParts, workArea,
$"{strategyName}: {i + 1}/{bestFits.Count} pairs, best = {bestScore.Count} parts");
}
return bestParts ?? new List<Part>();
}
private List<BestFitResult> GetPairCandidates()
{
List<BestFitResult> bestFits;
if (_context.SharedState.TryGetValue("BestFits", out var cached))
bestFits = (List<BestFitResult>)cached;
else
bestFits = BestFitCache.GetOrCompute(
_context.Item.Drawing,
_context.Plate.Size.Length,
_context.Plate.Size.Width,
_context.Plate.PartSpacing);
return bestFits
.Where(r => r.Keep)
.Take(MaxPairCandidates)
.ToList();
}
private static Box MakeStripeBox(Box workArea, double perpDim, NestDirection primaryAxis)
{
return primaryAxis == NestDirection.Horizontal
? new Box(workArea.X, workArea.Y, workArea.Width, perpDim)
: new Box(workArea.X, workArea.Y, perpDim, workArea.Length);
}
private List<Part> FillRemnant(
List<Part> gridParts, Drawing drawing, double angle,
Box workArea, double spacing)
{
var gridBox = gridParts.GetBoundingBox();
var minDim = System.Math.Min(
drawing.Program.BoundingBox().Width,
drawing.Program.BoundingBox().Length);
Box remnantBox;
if (_primaryAxis == NestDirection.Horizontal)
{
var remnantY = gridBox.Top + spacing;
var remnantLength = workArea.Top - remnantY;
if (remnantLength < minDim)
return null;
remnantBox = new Box(workArea.X, remnantY, workArea.Width, remnantLength);
}
else
{
var remnantX = gridBox.Right + spacing;
var remnantWidth = workArea.Right - remnantX;
if (remnantWidth < minDim)
return null;
remnantBox = new Box(remnantX, workArea.Y, remnantWidth, workArea.Length);
}
var engine = new FillLinear(remnantBox, spacing);
var parts = engine.Fill(drawing, angle, _primaryAxis);
return parts != null && parts.Count > 0 ? parts : null;
}
public static double FindAngleForTargetSpan(
List<Part> patternParts, double targetSpan, NestDirection axis)
{
var bestAngle = 0.0;
var bestDiff = double.MaxValue;
var samples = new (double angle, double span)[AngleSamples + 1];
for (var i = 0; i <= AngleSamples; i++)
{
var angle = i * Angle.HalfPI / AngleSamples;
var span = GetRotatedSpan(patternParts, angle, axis);
samples[i] = (angle, span);
var diff = System.Math.Abs(span - targetSpan);
if (diff < bestDiff)
{
bestDiff = diff;
bestAngle = angle;
}
}
if (bestDiff < Tolerance.Epsilon)
return bestAngle;
for (var i = 0; i < samples.Length - 1; i++)
{
var (a1, s1) = samples[i];
var (a2, s2) = samples[i + 1];
if ((s1 <= targetSpan && targetSpan <= s2) ||
(s2 <= targetSpan && targetSpan <= s1))
{
var result = BisectForTarget(patternParts, a1, a2, targetSpan, axis);
var resultSpan = GetRotatedSpan(patternParts, result, axis);
var resultDiff = System.Math.Abs(resultSpan - targetSpan);
if (resultDiff < bestDiff)
{
bestDiff = resultDiff;
bestAngle = result;
}
}
}
return bestAngle;
}
/// <summary>
/// Iteratively finds the rotation angle where N copies of the pattern
/// span the given dimension with minimal waste.
/// Returns (angle, waste, pairCount).
/// </summary>
public static (double Angle, double Waste, int Count) ConvergeStripeAngle(
List<Part> patternParts, double sheetSpan, double spacing,
NestDirection axis, CancellationToken token = default)
{
var currentAngle = 0.0;
var bestWaste = double.MaxValue;
var bestAngle = 0.0;
var bestCount = 0;
var tolerance = sheetSpan * 0.001;
for (var iteration = 0; iteration < MaxConvergenceIterations; iteration++)
{
token.ThrowIfCancellationRequested();
var rotated = FillHelpers.BuildRotatedPattern(patternParts, currentAngle);
var pairSpan = GetDimension(rotated.BoundingBox, axis);
if (pairSpan + spacing <= 0)
break;
var n = (int)System.Math.Floor((sheetSpan + spacing) / (pairSpan + spacing));
if (n <= 0)
break;
var usedSpan = n * (pairSpan + spacing) - spacing;
var remaining = sheetSpan - usedSpan;
if (remaining < bestWaste)
{
bestWaste = remaining;
bestAngle = currentAngle;
bestCount = n;
}
if (remaining <= tolerance)
break;
var delta = remaining / n;
var targetSpan = pairSpan + delta;
currentAngle = FindAngleForTargetSpan(patternParts, targetSpan, axis);
}
return (bestAngle, bestWaste, bestCount);
}
private static double BisectForTarget(
List<Part> patternParts, double lo, double hi,
double targetSpan, NestDirection axis)
{
var bestAngle = lo;
var bestDiff = double.MaxValue;
for (var i = 0; i < 30; i++)
{
var mid = (lo + hi) / 2;
var span = GetRotatedSpan(patternParts, mid, axis);
var diff = System.Math.Abs(span - targetSpan);
if (diff < bestDiff)
{
bestDiff = diff;
bestAngle = mid;
}
if (diff < Tolerance.Epsilon)
break;
var loSpan = GetRotatedSpan(patternParts, lo, axis);
if ((loSpan < targetSpan && span < targetSpan) ||
(loSpan > targetSpan && span > targetSpan))
lo = mid;
else
hi = mid;
}
return bestAngle;
}
private static double GetRotatedSpan(
List<Part> patternParts, double angle, NestDirection axis)
{
var rotated = FillHelpers.BuildRotatedPattern(patternParts, angle);
return axis == NestDirection.Horizontal
? rotated.BoundingBox.Width
: rotated.BoundingBox.Length;
}
private static double GetDimension(Box box, NestDirection axis)
{
return axis == NestDirection.Horizontal ? box.Width : box.Length;
}
}