public static SKTextBlob Create(ReadOnlySpan <char> text, SKFont font, SKPoint origin = default)
{
fixed(void *t = text)
{
return(Create(t, text.Length * 2, SKTextEncoding.Utf16, font, origin));
}
}
public static SKTextBlob CreateRotationScale(ReadOnlySpan <char> text, SKFont font, ReadOnlySpan <SKRotationScaleMatrix> positions)
{
fixed(void *t = text)
{
return(CreateRotationScale(t, text.Length * 2, SKTextEncoding.Utf16, font, positions));
}
}
public void DrawText(string text, float x, float y, SKFont font, SKPaint paint)
{
if (text == null)
{
throw new ArgumentNullException(nameof(text));
}
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
if (paint == null)
{
throw new ArgumentNullException(nameof(paint));
}
if (paint.TextAlign != SKTextAlign.Left)
{
var width = font.MeasureText(text);
if (paint.TextAlign == SKTextAlign.Center)
{
width *= 0.5f;
}
x -= width;
}
using var blob = SKTextBlob.Create(text, font);
if (blob == null)
{
return;
}
DrawText(blob, x, y, paint);
}
public static SKTextBlob CreatePositioned(ReadOnlySpan <char> text, SKFont font, ReadOnlySpan <SKPoint> positions)
{
fixed(void *t = text)
{
return(CreatePositioned(t, text.Length * 2, SKTextEncoding.Utf16, font, positions));
}
}
public static SKTextBlob CreateHorizontal(ReadOnlySpan <char> text, SKFont font, ReadOnlySpan <float> positions, float y)
{
fixed(void *t = text)
{
return(CreateHorizontal(t, text.Length * 2, SKTextEncoding.Utf16, font, positions, y));
}
}
public static SKTextBlob CreatePathPositioned(ReadOnlySpan <char> text, SKFont font, SKPath path, SKTextAlign textAlign = SKTextAlign.Left, SKPoint origin = default)
{
fixed(void *t = text)
{
return(CreatePathPositioned(t, text.Length * 2, SKTextEncoding.Utf16, font, path, textAlign, origin));
}
}
// AddPathPositionedRun
public void AddPathPositionedRun(ReadOnlySpan <ushort> glyphs, SKFont font, ReadOnlySpan <float> glyphWidths, ReadOnlySpan <SKPoint> glyphOffsets, SKPath path, SKTextAlign textAlign = SKTextAlign.Left)
{
using var pathMeasure = new SKPathMeasure(path);
var contourLength = pathMeasure.Length;
var textLength = glyphOffsets[glyphs.Length - 1].X + glyphWidths[glyphs.Length - 1];
var alignment = (int)textAlign * 0.5f;
var startOffset = glyphOffsets[0].X + (contourLength - textLength) * alignment;
var firstGlyphIndex = 0;
var pathGlyphCount = 0;
using var glyphTransforms = Utils.RentArray <SKRotationScaleMatrix> (glyphs.Length);
// TODO: deal with multiple contours?
for (var index = 0; index < glyphOffsets.Length; index++)
{
var glyphOffset = glyphOffsets[index];
var halfWidth = glyphWidths[index] * 0.5f;
var pathOffset = startOffset + glyphOffset.X + halfWidth;
// TODO: clip glyphs on both ends of paths
if (pathOffset >= 0 && pathOffset < contourLength && pathMeasure.GetPositionAndTangent(pathOffset, out var position, out var tangent))
{
if (pathGlyphCount == 0)
{
firstGlyphIndex = index;
}
var tx = tangent.X;
var ty = tangent.Y;
var px = position.X;
var py = position.Y;
// horizontally offset the position using the tangent vector
px -= tx * halfWidth;
py -= ty * halfWidth;
// vertically offset the position using the normal vector (-ty, tx)
var dy = glyphOffset.Y;
px -= dy * ty;
py += dy * tx;
glyphTransforms.Span[pathGlyphCount++] = new SKRotationScaleMatrix(tx, ty, px, py);
}
}
var glyphSubset = glyphs.Slice(firstGlyphIndex, pathGlyphCount);
var positions = glyphTransforms.Span.Slice(0, pathGlyphCount);
AddRotationScaleRun(glyphSubset, font, positions);
}
// AddHorizontalRun
public void AddHorizontalRun(ReadOnlySpan <ushort> glyphs, SKFont font, ReadOnlySpan <float> positions, float y)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var buffer = AllocateHorizontalRun(font, glyphs.Length, y);
glyphs.CopyTo(buffer.GetGlyphSpan());
positions.CopyTo(buffer.GetPositionSpan());
}
// AddPositionedRun
public void AddPositionedRun(ReadOnlySpan <ushort> glyphs, SKFont font, ReadOnlySpan <SKPoint> positions)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var buffer = AllocatePositionedRun(font, glyphs.Length);
glyphs.CopyTo(buffer.GetGlyphSpan());
positions.CopyTo(buffer.GetPositionSpan());
}
// AddRotationScaleRun
public void AddRotationScaleRun(ReadOnlySpan <ushort> glyphs, SKFont font, ReadOnlySpan <SKRotationScaleMatrix> positions)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var buffer = AllocateRotationScaleRun(font, glyphs.Length);
glyphs.CopyTo(buffer.GetGlyphSpan());
positions.CopyTo(buffer.GetRotationScaleSpan());
}
// AddRun
public void AddRun(ReadOnlySpan <ushort> glyphs, SKFont font, SKPoint origin = default)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var buffer = AllocatePositionedRun(font, glyphs.Length);
glyphs.CopyTo(buffer.GetGlyphSpan());
font.GetGlyphPositions(buffer.GetGlyphSpan(), buffer.GetPositionSpan(), origin);
}
// AllocateRotationScaleRun
public SKRotationScaleRunBuffer AllocateRotationScaleRun(SKFont font, int count)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
SKRunBufferInternal runbuffer;
SkiaApi.sk_textblob_builder_alloc_run_rsxform(Handle, font.Handle, count, &runbuffer);
return(new SKRotationScaleRunBuffer(runbuffer, count));
}
public SKPaint(SKFont font)
: this(IntPtr.Zero, true)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
Handle = SkiaApi.sk_compatpaint_new_with_font(font.Handle);
if (Handle == IntPtr.Zero)
{
throw new InvalidOperationException("Unable to create a new SKPaint instance.");
}
}
// AllocatePositionedRun
public SKPositionedRunBuffer AllocatePositionedRun(SKFont font, int count, SKRect?bounds = null)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
SKRunBufferInternal runbuffer;
if (bounds is SKRect b)
{
SkiaApi.sk_textblob_builder_alloc_run_pos(Handle, font.Handle, count, &b, &runbuffer);
}
else
{
SkiaApi.sk_textblob_builder_alloc_run_pos(Handle, font.Handle, count, null, &runbuffer);
}
return(new SKPositionedRunBuffer(runbuffer, count));
}
// CreateHorizontal
public static SKTextBlob CreateHorizontal(string text, SKFont font, ReadOnlySpan <float> positions, float y) =>
CreateHorizontal(text.AsSpan(), font, positions, y);
internal static SKTextBlob Create(void *text, int length, SKTextEncoding encoding, SKFont font, SKPoint origin)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var count = font.CountGlyphs(text, length, encoding);
if (count <= 0)
{
return(null);
}
using var builder = new SKTextBlobBuilder();
var buffer = builder.AllocatePositionedRun(font, count);
font.GetGlyphs(text, length, encoding, buffer.GetGlyphSpan());
font.GetGlyphPositions(buffer.GetGlyphSpan(), buffer.GetPositionSpan(), origin);
return(builder.Build());
}
public static SKTextBlob Create(ReadOnlySpan <byte> text, SKTextEncoding encoding, SKFont font, SKPoint origin = default)
{
fixed(void *t = text)
{
return(Create(t, text.Length, encoding, font, origin));
}
}
internal static SKTextBlob CreatePathPositioned(void *text, int length, SKTextEncoding encoding, SKFont font, SKPath path, SKTextAlign textAlign = SKTextAlign.Left, SKPoint origin = default)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var count = font.CountGlyphs(text, length, encoding);
if (count <= 0)
{
return(null);
}
// we use temporary arrays because we might only use part of the text
using var glyphs = Utils.RentArray <ushort> (count);
using var glyphWidths = Utils.RentArray <float> (glyphs.Length);
using var glyphOffsets = Utils.RentArray <SKPoint> (glyphs.Length);
font.GetGlyphs(text, length, encoding, glyphs);
font.GetGlyphWidths(glyphs, glyphWidths, Span <SKRect> .Empty);
font.GetGlyphPositions(glyphs, glyphOffsets, origin);
using var builder = new SKTextBlobBuilder();
builder.AddPathPositionedRun(glyphs, font, glyphWidths, glyphOffsets, path, textAlign);
return(builder.Build());
}
internal static SKTextBlob CreateHorizontal(void *text, int length, SKTextEncoding encoding, SKFont font, ReadOnlySpan <float> positions, float y)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
var count = font.CountGlyphs(text, length, encoding);
if (count <= 0)
{
return(null);
}
using var builder = new SKTextBlobBuilder();
var buffer = builder.AllocateHorizontalRun(font, count, y);
font.GetGlyphs(text, length, encoding, buffer.GetGlyphSpan());
positions.CopyTo(buffer.GetPositionSpan());
return(builder.Build());
}
// CreateRotationScale
public static SKTextBlob CreateRotationScale(string text, SKFont font, ReadOnlySpan <SKRotationScaleMatrix> positions) =>
CreateRotationScale(text.AsSpan(), font, positions);
public static SKTextBlob CreateRotationScale(IntPtr text, int length, SKTextEncoding encoding, SKFont font, ReadOnlySpan <SKRotationScaleMatrix> positions) => CreateRotationScale(text.AsReadOnlySpan(length), encoding, font, positions);
// CreatePathPositioned
public static SKTextBlob CreatePathPositioned(string text, SKFont font, SKPath path, SKTextAlign textAlign = SKTextAlign.Left, SKPoint origin = default) =>
CreatePathPositioned(text.AsSpan(), font, path, textAlign, origin);
// Create
public static SKTextBlob Create(string text, SKFont font, SKPoint origin = default) =>
Create(text.AsSpan(), font, origin);
public static SKTextBlob CreatePositioned(IntPtr text, int length, SKTextEncoding encoding, SKFont font, ReadOnlySpan <SKPoint> positions) => CreatePositioned(text.AsReadOnlySpan(length), encoding, font, positions);
public static SKTextBlob CreateHorizontal(IntPtr text, int length, SKTextEncoding encoding, SKFont font, ReadOnlySpan <float> positions, float y) => CreateHorizontal(text.AsReadOnlySpan(length), encoding, font, positions, y);
public static SKTextBlob CreatePositioned(ReadOnlySpan <byte> text, SKTextEncoding encoding, SKFont font, ReadOnlySpan <SKPoint> positions)
{
fixed(void *t = text)
{
return(CreatePositioned(t, text.Length, encoding, font, positions));
}
}
public static SKTextBlob Create(IntPtr text, int length, SKTextEncoding encoding, SKFont font, SKPoint origin = default) => Create(text.AsReadOnlySpan(length), encoding, font, origin);
public static SKTextBlob CreatePathPositioned(IntPtr text, int length, SKTextEncoding encoding, SKFont font, SKPath path, SKTextAlign textAlign = SKTextAlign.Left, SKPoint origin = default) => CreatePathPositioned(text.AsReadOnlySpan(length), encoding, font, path, textAlign, origin);
public void DrawTextOnPath(string text, SKPath path, SKPoint offset, bool warpGlyphs, SKFont font, SKPaint paint)
{
if (text == null)
{
throw new ArgumentNullException(nameof(text));
}
if (path == null)
{
throw new ArgumentNullException(nameof(path));
}
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
if (paint == null)
{
throw new ArgumentNullException(nameof(paint));
}
if (warpGlyphs)
{
using var textPath = font.GetTextPathOnPath(text, path, paint.TextAlign, offset);
DrawPath(textPath, paint);
}
else
{
using var blob = SKTextBlob.CreatePathPositioned(text, font, path, paint.TextAlign, offset);
if (blob != null)
{
DrawText(blob, 0, 0, paint);
}
}
}
// CreatePositioned
public static SKTextBlob CreatePositioned(string text, SKFont font, ReadOnlySpan <SKPoint> positions) =>
CreatePositioned(text.AsSpan(), font, positions);
