/// <summary>
/// Shape an array of utf-32 code points replacing each grapheme cluster with a replacement character
/// </summary>
/// <param name="bufferSet">A re-usable text shaping buffer set that results will be allocated from</param>
/// <param name="codePoints">The utf-32 code points to be shaped</param>
/// <param name="style">The user style for the text</param>
/// <param name="clusterAdjustment">A value to add to all reported cluster numbers</param>
/// <returns>A TextShaper.Result representing the shaped text</returns>
public Result ShapeReplacement(ResultBufferSet bufferSet, Slice <int> codePoints, IStyle style, int clusterAdjustment)
{
var clusters = GraphemeClusterAlgorithm.GetBoundaries(codePoints).ToArray();
var glyph = _typeface.GetGlyph(style.ReplacementCharacter);
var font = new SKFont(_typeface, overScale);
float glyphScale = style.FontSize / overScale;
float[] widths = new float[1];
SKRect[] bounds = new SKRect[1];
font.GetGlyphWidths((new ushort[] { glyph }).AsSpan(), widths.AsSpan(), bounds.AsSpan());
var r = new Result();
r.GlyphIndicies = bufferSet.GlyphIndicies.Add((int)clusters.Length - 1, false);
r.GlyphPositions = bufferSet.GlyphPositions.Add((int)clusters.Length - 1, false);
r.Clusters = bufferSet.Clusters.Add((int)clusters.Length - 1, false);
r.CodePointXCoords = bufferSet.CodePointXCoords.Add(codePoints.Length, false);
r.CodePointXCoords.Fill(0);
float xCoord = 0;
for (int i = 0; i < clusters.Length - 1; i++)
{
r.GlyphPositions[i].X = xCoord * glyphScale;
r.GlyphPositions[i].Y = 0;
r.GlyphIndicies[i] = codePoints[clusters[i]] == 0x2029 ? (ushort)0 : glyph;
r.Clusters[i] = clusters[i] + clusterAdjustment;
for (int j = clusters[i]; j < clusters[i + 1]; j++)
{
r.CodePointXCoords[j] = r.GlyphPositions[i].X;
}
xCoord += widths[0] + style.LetterSpacing / glyphScale;
}
// Also return the end cursor position
r.EndXCoord = new SKPoint(xCoord * glyphScale, 0);
// And some other useful metrics
r.Ascent = _fontMetrics.Ascent * style.FontSize / overScale;
r.Descent = _fontMetrics.Descent * style.FontSize / overScale;
r.XMin = _fontMetrics.XMin * style.FontSize / overScale;
return(r);
}