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[API Proposal] System.Drawing.Drawing2D.GraphicsPathIterator.CopyData spanify

See original GitHub issue

Background and motivation

When converting graphicsPaths I’m iterating over a lot of subpaths.

for (int i = ...
{
// ...
                   var subPathPoints = new GDIP.PointF[cnt];
                    var subPathTypes = new byte[cnt];
                    pathIterator.CopyData(ref subPathPoints, ref subPathTypes, startIndexSubPath, endIndexSubPath);
 }

I’d like rent the subPathPoints and subPathTypes from an ArrayPool. Because the arraypool would give me larger arrays, I should need to use Spans and slice them to the actual size.

original question: Can a CopyData overload using Spans be added?

API Proposal

Something like this, I’ll let the experts decide the best method parameters/overloads and datatypes

namespace System.Drawing.Drawing2D {

  public class GraphicsPathIterator 
  {
     public int CopyData (Span<System.Drawing.PointF> points, Span<byte types, int startIndex, int endIndex);

  }
}

API Usage

for (int i = ...
{
// ...
                    pathIterator.CopyData(Span<PointF> subPathPoints, Span<byte> subPathTypes, startIndexSubPath, endIndexSubPath);
 }