网站是哪个公司做的,天津百度推广公司电话,wordpress大学模板2.7,做网站营销怎么去推广文章目录 SKCanvas 方法Clear 清空ClipPath/ClipRect/ClipRegion/ClipRoundRect 设置裁切区域Concat 连接矩阵DrawAnnotation绘制注释DrawArc绘制椭圆弧、扇形DrawAtlas绘制图集(一个图像、多个区域、多个缩放、一次绘制#xff09;DrawBitmap绘制图像DrawBitmapNinePatch九宫… 文章目录 SKCanvas 方法Clear 清空ClipPath/ClipRect/ClipRegion/ClipRoundRect 设置裁切区域Concat 连接矩阵DrawAnnotation绘制注释DrawArc绘制椭圆弧、扇形DrawAtlas绘制图集(一个图像、多个区域、多个缩放、一次绘制DrawBitmap绘制图像DrawBitmapNinePatch九宫格绘图DrawBitmapLattice 格子绘图DrawCircle 绘制圆 SKCanvas 方法
Clear 清空
public void Clear ();//清空为#00000000
public void Clear (SkiaSharp.SKColor color);
public void Clear (SkiaSharp.SKColorF color);用指定颜色替换当前裁切区域的所有像素颜色。
ClipPath/ClipRect/ClipRegion/ClipRoundRect 设置裁切区域
public void ClipPath (SkiaSharp.SKPath path, SkiaSharp.SKClipOperation operation SkiaSharp.SKClipOperation.Intersect, bool antialias false);
public void ClipRect (SkiaSharp.SKRect rect, SkiaSharp.SKClipOperation operation SkiaSharp.SKClipOperation.Intersect, bool antialias false);
public void ClipRegion (SkiaSharp.SKRegion region, SkiaSharp.SKClipOperation operation SkiaSharp.SKClipOperation.Intersect);
public void ClipRegion (SkiaSharp.SKRegion region, SkiaSharp.SKClipOperation operation SkiaSharp.SKClipOperation.Intersect);使用指定的路径修改当前裁切区域。 SKClipOperation
值说明Difference从原区域减去指定区域Intersect原区域与指定区域的交集
var canvas e.Surface.Canvas;
var info e.Info;using(var paintnew SKPaint())
{paint.TextSize 18;paint.Color SKColors.Red;var path new SKPath();path.AddCircle(200, 200, 100);canvas.Save();canvas.ClipPath(path);canvas.Clear(SKColors.LightGreen);canvas.DrawText($ClipPath, 150, 200, paint);canvas.Restore();canvas.Save();canvas.ClipRect(new SKRect(250, 100, 550, 300));canvas.Clear(SKColors.LightBlue);canvas.DrawText($ClipRect, 350, 200, paint);canvas.Restore();canvas.Save();canvas.ClipRegion(new SKRegion(new SKRectI(100, 280, 300, 450)));canvas.Clear(SKColors.LightPink);canvas.DrawText($ClipRegion, 120, 400, paint);canvas.Restore();canvas.ClipRoundRect(new SKRoundRect(new SKRect(350, 350, 600, 600), 50));canvas.Clear(SKColors.LightCyan);canvas.DrawText($ClipRoundRect, 400, 450, paint);
}
分配使用ClipPath、ClipRect、ClipRegion、ClipRoundRect修改裁切区域。 注意还原裁切区域需要使用SKCanvas的Save()与Restore()方法。
Concat 连接矩阵
public void Concat (ref SkiaSharp.SKMatrix m);原SKCanvas的矩阵与指定合并。
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);
using (var paint new SKPaint())
{paint.TextSize 18;paint.Color SKColors.LightGreen;paint.IsStroke true;var rect new SKRect(50, 50, 250, 150);canvas.DrawRect(rect, paint);canvas.DrawText($TotalMatrix:{string.Join(,, canvas.TotalMatrix.Values)}, 400, 100, paint);var matrixA SKMatrix.CreateTranslation(50, 50);canvas.Concat(ref matrixA);canvas.DrawRect(rect, paint);canvas.DrawText($TotalMatrix:{string.Join(,, canvas.TotalMatrix.Values)}, 400, 100, paint);canvas.Concat(ref matrixA);canvas.DrawRect(rect, paint);canvas.DrawText($TotalMatrix:{string.Join(,, canvas.TotalMatrix.Values)}, 400, 100, paint);
}DrawAnnotation绘制注释
public void DrawAnnotation (SkiaSharp.SKRect rect, string key, SkiaSharp.SKData value);绘制注释。只在某些SKCanvas中有效如PDF doc生成的SKCanvas) 实测使用CreatePdf也没成功。
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);using (var stream File.OpenWrite(Images\test.pdf))
using (var doc SKDocument.CreatePdf(stream,72))
using (var pdfCanvas doc.BeginPage(600, 600))
using (var paint new SKPaint())
{paint.TextSize 18;paint.Color SKColors.LightGreen;paint.IsStroke true;var rect new SKRect(50, 50, 250, 150);pdfCanvas.DrawRect(rect, paint);using (MemoryStream byteStream new MemoryStream(Encoding.UTF8.GetBytes(This is rect annotation))){// 重置流的位置byteStream.Position 0;using (var annoData SKData.Create(byteStream)){//生成的PDF没看到pdfCanvas.DrawAnnotation(rect, Rect Anno, annoData);}}pdfCanvas.DrawText($Test DrawAnnotation, 20, 200, paint);doc.EndPage();doc.Close();
}DrawArc绘制椭圆弧、扇形
public void DrawArc (SkiaSharp.SKRect oval, float startAngle, float sweepAngle, bool useCenter, SkiaSharp.SKPaint paint);参数说明oval确定弧所在椭圆的矩形startAngle起始角度sweepAngle持续角度(正数顺时针负数逆时针)useCentertrue:扇形false:弧
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);using (var paint new SKPaint())
{paint.TextSize 18;paint.Color SKColors.Red;paint.IsStroke true;paint.StrokeWidth 5;var rect new SKRect(50, 50, 250, 150);//顺时针120度canvas.DrawArc(rect, 0, 120, false, paint);paint.Color SKColors.Green;//逆时针120度canvas.DrawArc(rect, 0, -120, false, paint);paint.Color SKColors.Blue;//扇形canvas.DrawArc(rect, 120, 120, true, paint);
}分三段绘制其中一段为扇形。
DrawAtlas绘制图集(一个图像、多个区域、多个缩放、一次绘制
public void DrawAtlas (SkiaSharp.SKImage atlas, SkiaSharp.SKRect[] sprites, SkiaSharp.SKRotationScaleMatrix[] transforms, SkiaSharp.SKPaint paint);
public void DrawAtlas (SkiaSharp.SKImage atlas, SkiaSharp.SKRect[] sprites, SkiaSharp.SKRotationScaleMatrix[] transforms, SkiaSharp.SKColor[] colors, SkiaSharp.SKBlendMode mode, SkiaSharp.SKPaint paint);
public void DrawAtlas (SkiaSharp.SKImage atlas, SkiaSharp.SKRect[] sprites, SkiaSharp.SKRotationScaleMatrix[] transforms, SkiaSharp.SKColor[] colors, SkiaSharp.SKBlendMode mode, SkiaSharp.SKRect cullRect, SkiaSharp.SKPaint paint);通过指定多个原图像矩形区域和多个缩放矩阵将一张图像一次性绘制在画布上。
提高性能减少绘制调用的次数可以显著提高渲染性能尤其是在需要同时绘制大量小图像时。降低内存开销使用一个大图集而不是多个小图像可以减少纹理切换次数降低 GPU 内存开销。简化管理将多个图像集中在一个图集中便于管理和使用特别是在游戏开发或需要大量图形资源的应用中。
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);using (var paint new SKPaint())
{paint.Color SKColors.Red;if (skImg null) skImg SKImage.FromBitmap(SKBitmap.Decode(Images\wall.png));const int count 100;var srcRects new ListSKRect();var rotScaleMatrix new ListSKRotationScaleMatrix();var offsetY 0;var offsetX 0;for (int i 0; i count; i){srcRects.Add(SKRect.Create(skImg.Width, skImg.Height));rotScaleMatrix.Add(SKRotationScaleMatrix.CreateTranslation(offsetX, offsetY));offsetX skImg.Width;if (offsetX info.Width - skImg.Width){offsetX 0;offsetY skImg.Height;}}//模拟平铺canvas.DrawAtlas(skImg,srcRects.ToArray(), rotScaleMatrix.ToArray(), paint);
}模拟平铺的方式多次绘制同一张图像。
DrawBitmap绘制图像
public void DrawBitmap (SkiaSharp.SKBitmap bitmap, SkiaSharp.SKPoint p, SkiaSharp.SKPaint paint default);
public void DrawBitmap (SkiaSharp.SKBitmap bitmap, SkiaSharp.SKRect dest, SkiaSharp.SKPaint paint default);
public void DrawBitmap (SkiaSharp.SKBitmap bitmap, SkiaSharp.SKRect source, SkiaSharp.SKRect dest, SkiaSharp.SKPaint paint default);
public void DrawBitmap (SkiaSharp.SKBitmap bitmap, float x, float y, SkiaSharp.SKPaint paint default);将图像绘制到指定区域。注意先缩放或裁切到合适大小再绘制比直接绘制时缩放效率会高些。
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);using (var paint new SKPaint())
{paint.Color SKColors.Red;if (skBmp null){skBmp SKBitmap.Decode(Images\AIWoman.png);skBmp skBmp.Resize(new SKSizeI(400, 400), SKFilterQuality.High);}canvas.DrawBitmap(skBmp, new SKPoint(20, 20), paint);canvas.DrawBitmap(skBmp, new SKRect(440, 20, 440 300, 20 300), paint);var srcRect new SKRect(40, 40, 360, 360);canvas.DrawBitmap(skBmp, srcRect, new SKRect(20, 440, 20 srcRect.Width, 480 srcRect.Height), paint);
}DrawBitmapNinePatch九宫格绘图
public void DrawBitmapNinePatch (SkiaSharp.SKBitmap bitmap, SkiaSharp.SKRectI center, SkiaSharp.SKRect dst, SkiaSharp.SKPaint paint default);以九宫格形式绘制一幅图像通过指定中心矩形来局部缩放图像。九宫格中四个角保持不拉伸其中的随着目标矩形大小拉伸。 /// summary/// 绘制刻度和根据中心矩形绘制井字形/// /summary/// param namebmp/param/// param namecenterRectI/param/// returns/returnsprivate SKBitmap DrawLines(SKBitmap bmp,SKRectI centerRectI){var cloneBmp bmp.Copy();using (var paint new SKPaint())using (var sCanvas new SKCanvas(cloneBmp)){paint.Color SKColors.Red;paint.IsStroke true;for (var x 0; x cloneBmp.Width; x 10){sCanvas.DrawLine(x, 0, x, 10, paint);}sCanvas.DrawLine(0, 10, cloneBmp.Width, 10, paint);for (var y 0; y cloneBmp.Height; y 10){sCanvas.DrawLine(0, y, 10, y, paint);}sCanvas.DrawLine(10, 0, 10, cloneBmp.Height, paint);sCanvas.DrawLine(0, centerRectI.Top, cloneBmp.Width, centerRectI.Top, paint);sCanvas.DrawLine(0, centerRectI.Bottom, cloneBmp.Width, centerRectI.Bottom, paint);sCanvas.DrawLine(centerRectI.Left, 0, centerRectI.Left, cloneBmp.Height, paint);sCanvas.DrawLine(centerRectI.Right, 0, centerRectI.Right, cloneBmp.Height, paint);}return cloneBmp;}public void OnPaintSurface12_07(object sender, SkiaSharp.Views.Desktop.SKPaintGLSurfaceEventArgs e)
{var canvas e.Surface.Canvas;var info e.Info;canvas.Clear(SKColors.White);//中间矩形SKRectI centerRectI SKRectI.Empty;// 定义绘制目标矩形var dstRect new SKRect(0, 0, 400, 400);using (var paint new SKPaint()){paint.Color SKColors.Red;paint.TextSize 16;var skSizeI new SKSizeI(200, 200);centerRectI new SKRectI(10, 10, 60, 60);if (skBmp null){skBmp SKBitmap.Decode(Images\AIWoman.png);skBmp skBmp.Resize(new SKSizeI(200, 200), SKFilterQuality.High); } var bmpA DrawLines(skBmp, centerRectI);canvas.DrawBitmapNinePatch(bmpA, centerRectI, dstRect, paint);canvas.DrawText($Center Rect:{centerRectI}, 0, 430, paint);bmpA.Dispose();centerRectI new SKRectI(skBmp.Width/3,skBmp.Height/3,skBmp.Width*2/3,skBmp.Height*2/3);var bmpB DrawLines(skBmp, centerRectI);dstRect new SKRect(410, 0, 810, 400);canvas.DrawBitmapNinePatch(bmpB, centerRectI, dstRect, paint);canvas.DrawText($Center Rect:{centerRectI}, 410, 430, paint);bmpB.Dispose();}
}定义两个不同的中心矩形对同一幅图进行九宫格缩放观察它们之间的不同。
DrawBitmapLattice 格子绘图
public void DrawBitmapLattice (SkiaSharp.SKBitmap bitmap, SkiaSharp.SKLattice lattice, SkiaSharp.SKRect dst, SkiaSharp.SKPaint paint default);
public void DrawBitmapLattice (SkiaSharp.SKBitmap bitmap, int[] xDivs, int[] yDivs, SkiaSharp.SKRect dst, SkiaSharp.SKPaint paint default);按函数原型是对九宫格绘图的扩展可自定义长*宽个格子也可指定哪一排或哪一列的缩放、以及哪一格是透明还是颜色填色。但实际应用中相关的参数并不一定按实际指定的效果执行。
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);if (skBmp null)
{skBmp SKBitmap.Decode(Images\AIWoman.png);skBmp skBmp.Resize(new SKSizeI(200, 200), SKFilterQuality.High);
}var qtrWidth skBmp.Width / 4;
// 定义 Lattice
var lattice new SKLattice
{XDivs new int[] { qtrWidth, qtrWidth * 2, qtrWidth * 3 }, // X 方向上的分割位置YDivs new int[] { skBmp.Height / 3, 2 * skBmp.Height / 3 }, // Y 方向上的分割位置RectTypes new SKLatticeRectType[] // 定义每个网格的类型{SKLatticeRectType.FixedColor, SKLatticeRectType.Default, SKLatticeRectType.Default,SKLatticeRectType.FixedColor,SKLatticeRectType.FixedColor, SKLatticeRectType.Default, SKLatticeRectType.Default,SKLatticeRectType.FixedColor,SKLatticeRectType.FixedColor, SKLatticeRectType.Default, SKLatticeRectType.Default,SKLatticeRectType.FixedColor},Colors new SKColor[]{SKColors.Red, SKColors.Green, SKColors.Blue, SKColors.Yellow, SKColors.Cyan, SKColors.Magenta, SKColors.Orange, SKColors.Purple, SKColors.Gray,SKColors.Pink,SKColors.DarkBlue,SKColors.Gold}
};// 定义绘制目标矩形
var dstRect new SKRect(0, 0, 300, 300);using (var paint new SKPaint())
{paint.Color SKColors.Red;using (var sCanvas new SKCanvas(skBmp)){foreach (var x in lattice.XDivs){sCanvas.DrawLine(x, 0, x, skBmp.Height, paint);}foreach (var y in lattice.YDivs){sCanvas.DrawLine(0, y, skBmp.Width, y, paint);}}canvas.DrawBitmapLattice(skBmp, lattice, dstRect, paint);
}按 4 * 3 格子对图像进行缩放绘制
DrawCircle 绘制圆
public void DrawCircle (SkiaSharp.SKPoint c, float radius, SkiaSharp.SKPaint paint);
public void DrawCircle (float cx, float cy, float radius, SkiaSharp.SKPaint paint);绘制和填充圆。
var canvas e.Surface.Canvas;
var info e.Info;
canvas.Clear(SKColors.White);using(var paintnew SKPaint())
{paint.Style SKPaintStyle.StrokeAndFill;paint.Color SKColors.LightGreen;paint.TextSize 18;//实心圆canvas.DrawCircle(150, 150, 100, paint);canvas.DrawText($Fill Circle, 50, 280, paint);canvas.Translate(200, 0);paint.IsStroke true;//空心圆canvas.DrawCircle(150, 150, 100, paint);canvas.DrawText($Stroke Circle, 50, 280, paint);
}
绘制两个圆一个填充另一个只描边。
