/// <summary>
/// Create a SkiaSharp paint object to paint the ink stroke
/// </summary>
/// <param name="stroke">an ink stroke</param>
/// <param name="paintStyle">the paint style (default is
/// <see cref="SKPaintStyle.Stroke"/>)</param>
/// <param name="blendMode">the pencil drawing blend mode (default is
/// <see cref="SKBlendMode.SrcATop"/></param>
/// <returns>a tuple with the<see cref="SKPaint"/> object and any
/// disposable objects that need to be managed</returns>
public static Tuple <SKPaint, IEnumerable <IDisposable> > CreatePaint(this XInkStroke stroke, SKPaintStyle paintStyle = SKPaintStyle.Stroke, SKBlendMode blendMode = SKBlendMode.SrcATop)
{
if (stroke == null)
{
throw new ArgumentNullException(nameof(stroke));
}
var disposables = new List <IDisposable>();
SKShader shader = null;
if (stroke.DrawingAttributes.Kind == XInkDrawingAttributesKind.Pencil)
{
var perlin = SKShader.CreatePerlinNoiseFractalNoise(0.01f, 0.01f, 1, 1.0f);
var color = SKShader.CreateColor(stroke.DrawingAttributes.Color.ToSKColor().WithAlpha(0x7F));
disposables.Add(perlin);
disposables.Add(color);
shader = SKShader.CreateCompose(
perlin,
color,
blendMode);
}
Tuple <SKPaint, IEnumerable <IDisposable> > tuple = null;
SKPaint paint = null;
if (!stroke.DrawingAttributes.IgnorePressure)
{
paintStyle = SKPaintStyle.Fill;
}
try
{
paint = new SKPaint
{
Color = stroke.DrawingAttributes.Kind == XInkDrawingAttributesKind.Default ? stroke.DrawingAttributes.Color.ToSKColor() : new SKColor(),
StrokeWidth = stroke.DrawingAttributes.IgnorePressure ? stroke.DrawingAttributes.Size : 0.0f,
Style = paintStyle,
IsAntialias = true,
StrokeCap = stroke.DrawingAttributes.PenTip == Inking.XPenTipShape.Circle ? SKStrokeCap.Round : SKStrokeCap.Butt,
PathEffect = SKPathEffect.CreateCorner(100)
};
if (shader != null)
{
paint.Shader = shader;
}
tuple = Tuple.Create(paint, disposables as IEnumerable <IDisposable>);
paint = null;
}
finally
{
paint?.Dispose();
}
return(tuple);
}
SKSize MeasureAndPaint(SKCanvas canvas, SKMatrix matrix, SKPoint location, bool doPaint)
{
float[] values = matrix.Values;
string[] texts = new string[9];
SKRect[] bounds = new SKRect[9];
float[] widths = new float[3];
for (int i = 0; i < 9; i++)
{
int row = i % 3;
int col = i / 3;
// Format string differently based on row
texts[i] = values[i].ToString(row == 2 ? "F0" : (col == 2 ? PerspectiveFormat : "F2"));
// Measure string with a '-' even if one is not present
bool isNegative = texts[i][0] == '-';
string text = (isNegative ? "" : "-") + texts[i];
MatrixPaint.MeasureText(text, ref bounds[i]);
// Get maximum width for each column
widths[col] = Math.Max(widths[col], bounds[i].Width);
// Measure the text again without the '-' in front
MatrixPaint.MeasureText(texts[i], ref bounds[i]);
}
// Some formatting constants
float horzGap = MatrixPaint.TextSize;
float horzMarg = MatrixPaint.TextSize;
float vertMarg = MatrixPaint.FontSpacing / 4;
// Calculate the total width and height of the matrix display
float totalWidth = widths[0] + widths[1] + widths[2] + 2 * horzGap + 2 * horzMarg;
float totalHeight = 3 * MatrixPaint.FontSpacing + 2 * vertMarg;
if (doPaint)
{
SKPaintStyle saveStyle = MatrixPaint.Style;
for (int i = 0; i < 9; i++)
{
int row = i % 3;
int col = i / 3;
// Find x, y of upper-left corner of text
float x = location.X + horzMarg;
for (int c = 0; c < col; c++)
{
x += widths[c] + horzGap;
}
float y = location.Y + vertMarg + row * MatrixPaint.FontSpacing;
// Adjust for right-justified text
x += widths[col] - bounds[i].Width;
y += (MatrixPaint.FontSpacing - bounds[i].Height) / 2 - bounds[i].Top;
// Draw the text
MatrixPaint.Style = SKPaintStyle.Fill;
canvas.DrawText(texts[i], x, y, MatrixPaint);
}
// Display vertical lines at the sides of the matrix
MatrixPaint.Style = SKPaintStyle.Stroke;
canvas.DrawLine(location.X + horzMarg / 2, location.Y + vertMarg,
location.X + horzMarg / 2, location.Y + totalHeight - vertMarg, MatrixPaint);
canvas.DrawLine(location.X + totalWidth - horzMarg / 2, location.Y + vertMarg,
location.X + totalWidth - horzMarg / 2, location.Y + totalHeight - vertMarg, MatrixPaint);
MatrixPaint.Style = saveStyle;
}
return(new SKSize(totalWidth, totalHeight));
}
protected BaseTextStyle(SKPaintStyle paintStyle)
{
SKPaintStyle = paintStyle;
}
public extern static void sk_paint_set_style(sk_paint_t t, SKPaintStyle style);
public DefaultPaintStyleAttribute(SKPaintStyle fill, bool antialias = true)
{
Fill = fill;
Antialias = antialias;
}
public YCircle(SKPoint center, float radius, SKColor color, float strokeWidth, SKPaintStyle paintStyle)
{
Center = center;
Radius = radius;
Paint = new SKPaint
{
Style = paintStyle,
Color = color,
StrokeWidth = strokeWidth
};
}
