public ShapedBuffer ShapeText(ReadOnlySlice <char> text, TextShaperOptions options)
{
var typeface = options.Typeface;
var fontRenderingEmSize = options.FontRenderingEmSize;
var bidiLevel = options.BidLevel;
var culture = options.Culture;
using (var buffer = new Buffer())
{
buffer.AddUtf16(text.Buffer.Span, text.Start, text.Length);
MergeBreakPair(buffer);
buffer.GuessSegmentProperties();
buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);
var font = ((HarfBuzzGlyphTypefaceImpl)typeface.PlatformImpl).Font;
font.Shape(buffer);
if (buffer.Direction == Direction.RightToLeft)
{
buffer.Reverse();
}
font.GetScale(out var scaleX, out _);
var textScale = fontRenderingEmSize / scaleX;
var bufferLength = buffer.Length;
var shapedBuffer = new ShapedBuffer(text, bufferLength, typeface, fontRenderingEmSize, bidiLevel);
var glyphInfos = buffer.GetGlyphInfoSpan();
var glyphPositions = buffer.GetGlyphPositionSpan();
for (var i = 0; i < bufferLength; i++)
{
var sourceInfo = glyphInfos[i];
var glyphIndex = (ushort)sourceInfo.Codepoint;
var glyphCluster = (int)sourceInfo.Cluster;
var glyphAdvance = GetGlyphAdvance(glyphPositions, i, textScale);
var glyphOffset = GetGlyphOffset(glyphPositions, i, textScale);
var targetInfo = new Media.TextFormatting.GlyphInfo(glyphIndex, glyphCluster, glyphAdvance, glyphOffset);
shapedBuffer[i] = targetInfo;
}
return(shapedBuffer);
}
}
public void ShouldReverse()
{
using (var buffer = new Buffer())
{
buffer.AddUtf8("12");
buffer.Reverse();
Assert.Equal(50u, buffer.GlyphInfos[0].Codepoint);
Assert.Equal(1u, buffer.GlyphInfos[0].Cluster);
Assert.Equal(49u, buffer.GlyphInfos[1].Codepoint);
Assert.Equal(0u, buffer.GlyphInfos[1].Cluster);
}
}