C# WPF drawLine 大量线段的绘制

在WPF中绘制大量数量的线段时，绘制很慢，而且很耗CPU的资源。绘制到几百条线段时，就会明显无法交互操作。

通过查询资料，我们找到一个方法可以解决：使用StreamGeometry在内存中绘制，然后再Render到WPF的控件上。

实现如下：

using (var geometryContext = _cueGeometry.Open())

using (var perContext = _perGeometry.Open())

using (var _volContext = _volGeometry.Open())

{

for (int i = 0; i < TickLineValue.drawTickData.Count() - 1; i++)

{

TickLineValue.drawTickData[i].picTopY = topY;

TickLineValue.drawTickData[i].PriceMax = TickLineValue.tickMaxValue;

TickLineValue.drawTickData[i].PriceMin = TickLineValue.tickMinValue;

TickLineValue.drawTickData[i].ScreenTickHeight = TickLineValue.tickHeight;

TickLineValue.drawTickData[i].VolMax = TickLineValue.volMaxValue;

TickLineValue.drawTickData[i].picVolTopY = TickLineValue.lineObject.GetYValue() + TickLineValue.perPicTxtHeight;

TickLineValue.drawTickData[i].ScreenVolHeight = TickLineValue.volHeight;

//绘制图形的

x = TickLineValue.picLeftWidth + i * TickLineValue.picWidth;

//绘制tick

Point p0 = new Point();

p0.X = x;

p0.Y = TickLineValue.drawTickData[i].newPriceY;

if (i == 0)

{

geometryContext.BeginFigure(p0, true, false);

}

else

{

geometryContext.LineTo(p0, true, true);

}

//绘制均线

p0.Y = TickLineValue.drawTickData[i].perPriceY;

if (i == 0)

{

perContext.BeginFigure(p0, true, false);

}

else

{

perContext.LineTo(p0, true, true);

}

////绘制交易量

p0.Y = TickLineValue.drawTickData[i].tradeVolY;

Point p1 = new Point();

p1.X = x;

p1.Y = volY;

_volContext.BeginFigure(p0, true, false);

_volContext.LineTo(p1, true, true);

//绘制时间

strTime = TickLineValue.drawTickData[i].dateTime;

strTime = dealTimeString(strTime, oldTime);

if (strTime == "")

{

continue;

}

oldTime = strTime;

FormattedText t = new FormattedText(strTime, System.Globalization.CultureInfo.InvariantCulture,

FlowDirection.LeftToRight, new Typeface(fontFamily.ToString()), TickLineValue.timeFontSize,

timeB);

if (oldX<p0.X)

{

p0.Y = timeY;

dc.DrawText(t, p0);

oldX = p0.X + t.Width;

}

}

}

dc.DrawGeometry((Brush)null, tickPen, _cueGeometry);

dc.DrawGeometry((Brush)null, perPen, _perGeometry);

dc.DrawGeometry((Brush)null, volPen, _volGeometry);

}

catch (Exception ex)

{

TickLineValue.picErrorLog.log(5, "TickPictureCanvas|DrawPicTick|" + ex.ToString());

}

}

如果是连续的曲线，那么就使用一次BeginFigure(p0, true, false);如果是每次都是独立的线段，那么

就可以多次使用：BeginFigure(p0, true, false);