protected override void OnDrawSample(SKCanvas canvas, int width, int height)
{
canvas.Clear(SKColors.White);
var blockSize = 30;
// create the path
var path = new SKPath();
// the rect must be offset as the path uses the center
var rect = SKRect.Create(blockSize / -2, blockSize / -2, blockSize, blockSize);
path.AddRect(rect);
// move the path around: across 1 block
var offsetMatrix = SKMatrix.MakeScale(2 * blockSize, blockSize);
// each row, move across a bit / offset
SKMatrix.PreConcat(ref offsetMatrix, SKMatrix.MakeSkew(0.5f, 0));
// create the paint
var paint = new SKPaint();
paint.PathEffect = SKPathEffect.Create2DPath(offsetMatrix, path);
paint.Color = SKColors.LightGray;
// draw a rectangle
canvas.DrawRect(SKRect.Create(width, height), paint);
}
private void SKCanvasView_PaintSurface(object sender, SkiaSharp.Views.Forms.SKPaintSurfaceEventArgs e)
{
SKSurface surface = e.Surface;
SKCanvas canvas = surface.Canvas;
var scale = ((SKCanvasView)sender).CanvasSize.Width / 20;
SKPath path = new SKPath();
path.MoveTo(-1 * scale, -1 * scale);
path.LineTo(0 * scale, -1 * scale);
path.LineTo(0 * scale, 0 * scale);
path.LineTo(1 * scale, 0 * scale);
path.LineTo(1 * scale, 1 * scale);
path.LineTo(0 * scale, 1 * scale);
path.LineTo(0 * scale, 0 * scale);
path.LineTo(-1 * scale, 0 * scale);
path.LineTo(-1 * scale, -1 * scale);
SKMatrix matrix = SKMatrix.MakeScale(2 * scale, 2 * scale);
SKPaint paint = new SKPaint();
paint.PathEffect = SKPathEffect.Create2DPath(matrix, path);
paint.Color = Color.LightGray.ToSKColor();
paint.IsAntialias = true;
var patternRect = new SKRect(0, 0, ((SKCanvasView)sender).CanvasSize.Width, ((SKCanvasView)sender).CanvasSize.Height);
canvas.Save();
canvas.DrawRect(patternRect, paint);
canvas.Restore();
}
private void PaintChessPattern(SKCanvas canvas, SliderLocation slider, SKSize canvasSize)
{
var pickerRadiusPixels = GetPickerRadiusPixels();
var sliderTop = slider.GetSliderOffset(pickerRadiusPixels);
var scale = pickerRadiusPixels / 3;
SKPath path = new SKPath();
path.MoveTo(-1 * scale, -1 * scale);
path.LineTo(0 * scale, -1 * scale);
path.LineTo(0 * scale, 0 * scale);
path.LineTo(1 * scale, 0 * scale);
path.LineTo(1 * scale, 1 * scale);
path.LineTo(0 * scale, 1 * scale);
path.LineTo(0 * scale, 0 * scale);
path.LineTo(-1 * scale, 0 * scale);
path.LineTo(-1 * scale, -1 * scale);
SKMatrix matrix = SKMatrix.MakeScale(2 * scale, 2 * scale);
SKPaint paint = new SKPaint
{
PathEffect = SKPathEffect.Create2DPath(matrix, path),
Color = Color.LightGray.ToSKColor(),
IsAntialias = true
};
SKRect patternRect;
SKRect clipRect;
SKRoundRect clipRoundRect;
if (Vertical)
{
patternRect = new SKRect(sliderTop - pickerRadiusPixels, pickerRadiusPixels
, sliderTop + pickerRadiusPixels, canvasSize.Height - pickerRadiusPixels);
clipRect = new SKRect(sliderTop - (pickerRadiusPixels * 0.65f), pickerRadiusPixels * 1.35f
, sliderTop + (pickerRadiusPixels * 0.65f), canvasSize.Height - (pickerRadiusPixels * 1.35f));
clipRoundRect = new SKRoundRect(clipRect, pickerRadiusPixels * 0.65f, pickerRadiusPixels * 0.65f);
}
else
{
patternRect = new SKRect(pickerRadiusPixels, sliderTop - pickerRadiusPixels
, canvasSize.Width - pickerRadiusPixels, sliderTop + pickerRadiusPixels);
clipRect = new SKRect(pickerRadiusPixels * 1.35f, sliderTop - (pickerRadiusPixels * 0.65f)
, canvasSize.Width - (pickerRadiusPixels * 1.35f), sliderTop + (pickerRadiusPixels * 0.65f));
clipRoundRect = new SKRoundRect(clipRect, pickerRadiusPixels * 0.65f, pickerRadiusPixels * 0.65f);
}
canvas.Save();
canvas.ClipRoundRect(clipRoundRect);
canvas.DrawRect(patternRect, paint);
canvas.Restore();
}
private void DrawTransparencyBackground(SKCanvas canvas, int width, int height, float scale)
{
var blockSize = BaseBlockSize * scale;
var offsetMatrix = SKMatrix.MakeScale(2 * blockSize, blockSize);
var skewMatrix = SKMatrix.MakeSkew(0.5f, 0);
SKMatrix.PreConcat(ref offsetMatrix, ref skewMatrix);
using (var path = new SKPath())
using (var paint = new SKPaint())
{
path.AddRect(SKRect.Create(blockSize / -2, blockSize / -2, blockSize, blockSize));
paint.PathEffect = SKPathEffect.Create2DPath(offsetMatrix, path);
paint.Color = AlternatePaneColor;
canvas.DrawRect(SKRect.Create(width + blockSize, height + blockSize), paint);
}
}
private void OnPaintBackground(object sender, SKPaintSurfaceEventArgs e)
{
var scale = e.Info.Width / (float)((View)sender).Width;
var blockSize = BaseBlockSize * scale;
var offsetMatrix = SKMatrix.CreateScale(2 * blockSize, blockSize);
var skewMatrix = SKMatrix.CreateSkew(0.5f, 0);
var matrix = offsetMatrix.PreConcat(skewMatrix);
using var path = new SKPath();
path.AddRect(SKRect.Create(blockSize / -2, blockSize / -2, blockSize, blockSize));
using var paint = new SKPaint
{
PathEffect = SKPathEffect.Create2DPath(matrix, path),
Color = 0xFFF0F0F0
};
var canvas = e.Surface.Canvas;
var area = SKRect.Create(e.Info.Width + blockSize, e.Info.Height + blockSize);
canvas.DrawRect(area, paint);
}
void OnCanvasViewPaintSurface(object sender, SKPaintSurfaceEventArgs args)
{
SKImageInfo info = args.Info;
SKSurface surface = args.Surface;
SKCanvas canvas = surface.Canvas;
canvas.Clear();
using (SKPaint paint = new SKPaint())
{
paint.Color = SKColors.Red;
using (SKPathEffect pathEffect =
SKPathEffect.Create2DPath(SKMatrix.MakeScale(64, 64), tilePath))
{
paint.PathEffect = pathEffect;
canvas.DrawRoundRect(
new SKRect(50, 50, info.Width - 50, info.Height - 50),
100, 100, paint);
}
}
}
public CatsInFramePage()
{
Title = "Cats in Frame";
SKCanvasView canvasView = new SKCanvasView();
canvasView.PaintSurface += OnCanvasViewPaintSurface;
Content = canvasView;
// Move (0, 0) point to center of cat path
catPath.Transform(SKMatrix.MakeTranslation(-240, -175));
// Now catPath is 400 by 250
// Scale it down to 160 by 100
catPath.Transform(SKMatrix.MakeScale(0.40f, 0.40f));
// Get the outlines of the contours of the cat path
SKPath outlinedCatPath = new SKPath();
catStroke.GetFillPath(catPath, outlinedCatPath);
// Create a 2D path effect from those outlines
SKPathEffect fillEffect = SKPathEffect.Create2DPath(
new SKMatrix {
ScaleX = 170, ScaleY = 110,
TransX = 75, TransY = 80,
Persp2 = 1
},
outlinedCatPath);
// Create a 1D path effect from the scallop path
SKPathEffect strokeEffect =
SKPathEffect.Create1DPath(scallopPath, 75, 0, SKPath1DPathEffectStyle.Rotate);
// Set the sum the effects to frame paint
framePaint.PathEffect = SKPathEffect.CreateSum(fillEffect, strokeEffect);
}
public static void Draw(SKCanvas canvas, IReadOnlyViewport viewport, IStyle style, IFeature feature, IGeometry geometry,
float opacity, SymbolCache symbolCache = null)
{
if (style is LabelStyle labelStyle)
{
var worldCenter = geometry.BoundingBox.Centroid;
var center = viewport.WorldToScreen(worldCenter);
LabelRenderer.Draw(canvas, labelStyle, feature, (float)center.X, (float)center.Y, opacity);
}
else if (style is StyleCollection styleCollection)
{
foreach (var s in styleCollection)
{
Draw(canvas, viewport, s, feature, geometry, opacity, symbolCache);
}
}
else if (style is VectorStyle vectorStyle)
{
var polygon = (Polygon)geometry;
float lineWidth = 1;
var lineColor = Color.Black; // default
var fillColor = Color.Gray; // default
var strokeCap = PenStrokeCap.Butt; // default
var strokeJoin = StrokeJoin.Miter; // default
var strokeMiterLimit = 4f; // default
var strokeStyle = PenStyle.Solid; // default
float[] dashArray = null; // default
if (vectorStyle.Outline != null)
{
lineWidth = (float)vectorStyle.Outline.Width;
lineColor = vectorStyle.Outline.Color;
strokeCap = vectorStyle.Outline.PenStrokeCap;
strokeJoin = vectorStyle.Outline.StrokeJoin;
strokeMiterLimit = vectorStyle.Outline.StrokeMiterLimit;
strokeStyle = vectorStyle.Outline.PenStyle;
dashArray = vectorStyle.Outline.DashArray;
}
if (vectorStyle.Fill != null)
{
fillColor = vectorStyle.Fill?.Color;
}
using (var path = polygon.ToSkiaPath(viewport, canvas.LocalClipBounds, lineWidth))
using (var paintFill = new SKPaint {
IsAntialias = true
})
{
// Is there a FillStyle?
if (vectorStyle.Fill?.FillStyle == FillStyle.Solid)
{
paintFill.StrokeWidth = 0;
paintFill.Style = SKPaintStyle.Fill;
paintFill.PathEffect = null;
paintFill.Shader = null;
paintFill.Color = fillColor.ToSkia(opacity);
canvas.DrawPath(path, paintFill);
}
else
{
paintFill.StrokeWidth = 1;
paintFill.Style = SKPaintStyle.Stroke;
paintFill.Shader = null;
paintFill.Color = fillColor.ToSkia(opacity);
var scale = 10.0f;
var fillPath = new SKPath();
var matrix = SKMatrix.MakeScale(scale, scale);
switch (vectorStyle.Fill?.FillStyle)
{
case FillStyle.Cross:
fillPath.MoveTo(scale * 0.8f, scale * 0.8f);
fillPath.LineTo(0, 0);
fillPath.MoveTo(0, scale * 0.8f);
fillPath.LineTo(scale * 0.8f, 0);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.DiagonalCross:
fillPath.MoveTo(scale, scale);
fillPath.LineTo(0, 0);
fillPath.MoveTo(0, scale);
fillPath.LineTo(scale, 0);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.BackwardDiagonal:
fillPath.MoveTo(0, scale);
fillPath.LineTo(scale, 0);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.ForwardDiagonal:
fillPath.MoveTo(scale, scale);
fillPath.LineTo(0, 0);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.Dotted:
paintFill.Style = SKPaintStyle.StrokeAndFill;
fillPath.AddCircle(scale * 0.5f, scale * 0.5f, scale * 0.35f);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.Horizontal:
fillPath.MoveTo(0, scale * 0.5f);
fillPath.LineTo(scale, scale * 0.5f);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.Vertical:
fillPath.MoveTo(scale * 0.5f, 0);
fillPath.LineTo(scale * 0.5f, scale);
paintFill.PathEffect = SKPathEffect.Create2DPath(matrix, fillPath);
break;
case FillStyle.Bitmap:
paintFill.Style = SKPaintStyle.Fill;
var image = GetImage(symbolCache, vectorStyle.Fill.BitmapId);
if (image != null)
{
paintFill.Shader = image.ToShader(SKShaderTileMode.Repeat, SKShaderTileMode.Repeat);
}
break;
case FillStyle.BitmapRotated:
paintFill.Style = SKPaintStyle.Fill;
image = GetImage(symbolCache, vectorStyle.Fill.BitmapId);
if (image != null)
{
paintFill.Shader = image.ToShader(SKShaderTileMode.Repeat,
SKShaderTileMode.Repeat,
SKMatrix.MakeRotation((float)(viewport.Rotation * System.Math.PI / 180.0f), image.Width >> 1, image.Height >> 1));
}
break;
default:
paintFill.PathEffect = null;
break;
}
// Do this, because if not, path isn't filled complete
using (new SKAutoCanvasRestore(canvas))
{
canvas.ClipPath(path);
var bounds = path.Bounds;
// Make sure, that the brush starts with the correct position
var inflate = ((int)path.Bounds.Width * 0.3f / scale) * scale;
bounds.Inflate(inflate, inflate);
// Draw rect with bigger size, which is clipped by path
canvas.DrawRect(bounds, paintFill);
}
}
if (vectorStyle.Outline != null)
{
using (var paintStroke = new SKPaint {
IsAntialias = true
})
{
paintStroke.Style = SKPaintStyle.Stroke;
paintStroke.StrokeWidth = lineWidth;
paintStroke.Color = lineColor.ToSkia(opacity);
paintStroke.StrokeCap = strokeCap.ToSkia();
paintStroke.StrokeJoin = strokeJoin.ToSkia();
paintStroke.StrokeMiter = strokeMiterLimit;
if (strokeStyle != PenStyle.Solid)
{
paintStroke.PathEffect = strokeStyle.ToSkia(lineWidth, dashArray);
}
else
{
paintStroke.PathEffect = null;
}
canvas.DrawPath(path, paintStroke);
}
}
}
}
}