我正在使用C＃3.0使用.Net Compact Framework 3.5开发一个项目。
我有一个用户控件，每15毫秒接收一次数据，我必须绘制形状
像用户控件上的线条，矩形，填充矩形。
我想知道绘制这些形状的最快方法是什么，如果有一些方法可以提高性能和速度，我也可以使用P / Invoke方法。
我使用的代码如下：
private void DrawThreeFunctions(Graphics g)
{
// drawing back functions
if (DisplayFunction1.DrawOrder == DrawOrder.Back && GraphDataArray.Length > 0)
{
DrawFunction(g, DisplayFunction1, GraphDataArray[0]);
}
if (DisplayFunction2.DrawOrder == DrawOrder.Back && GraphDataArray.Length > 1)
{
DrawFunction(g, DisplayFunction2, GraphDataArray[1]);
}
if (DisplayFunction3.DrawOrder == DrawOrder.Back && GraphDataArray.Length > 2)
{
DrawFunction(g, DisplayFunction3, GraphDataArray[2]);
}
// drawing middle functions
if (DisplayFunction1.DrawOrder == DrawOrder.Middle && GraphDataArray.Length > 0)
{
DrawFunction(g, DisplayFunction1, GraphDataArray[0]);
}
if (DisplayFunction2.DrawOrder == DrawOrder.Middle && GraphDataArray.Length > 1)
{
DrawFunction(g, DisplayFunction2, GraphDataArray[1]);
}
if (DisplayFunction3.DrawOrder == DrawOrder.Middle && GraphDataArray.Length > 2)
{
DrawFunction(g, DisplayFunction3, GraphDataArray[2]);
}
// drawing front functions
if (DisplayFunction1.DrawOrder == DrawOrder.Front && GraphDataArray.Length > 0)
{
DrawFunction(g, DisplayFunction1, GraphDataArray[0]);
}
if (DisplayFunction2.DrawOrder == DrawOrder.Front && GraphDataArray.Length > 1)
{
DrawFunction(g, DisplayFunction2, GraphDataArray[1]);
}
if (DisplayFunction3.DrawOrder == DrawOrder.Front && GraphDataArray.Length > 2)
{
DrawFunction(g, DisplayFunction3, GraphDataArray[2]);
}
}
private void DrawFunction(Graphics g, DisplayFunction function, int[] data)
{
Color color = Utils.GetColor(function.Color);
switch (function.Shape)
{
case FunctionShape.StepLine:
DrawStepLines(g, data, color);
break;
case FunctionShape.Rectangle:
DrawFilledRectangles(g, data, color);
break;
case FunctionShape.FramedRectangle:
DrawFramedRectangles(g, data, color);
break;
case FunctionShape.Line:
DrawLines(g, data, color);
break;
default:
break;
}
}
#region Drawing methods
// drawing lines
private void DrawLines(Graphics g, int[] lineData, Color lineColor)
{
BarPositions = new List<int>();
List<Point> linePoints = new List<Point>();
int lineYPos = -1;
int lineXPos = FirstBarDrawPosition;
Point point = Point.Empty;
using (Pen linePen = new Pen(lineColor, 2.0f))
{
for (int i = FirstVisibleItemIndex, k = 0; i < _indexLimit; i++, k++)
{
if (base.GetBarEndPosition(k) > Width)
break;
lineXPos = GetTickPosition(k);
BarPositions.Add(lineXPos);
if (i < lineData.Length)
lineYPos = lineData[i];
else
continue;
point.X = lineXPos;
point.Y = lineYPos;
linePoints.Add(point);
}
if (linePoints.Any())
{
g.DrawLines(linePen, linePoints.ToArray());
}
}
}
// drawing framed rectangles
private void DrawFramedRectangles(Graphics g, int[] functionValues, Color functionColor)
{
BarPositions = new List<int>();
int barXPos = FirstBarDrawPosition;
Rectangle barRect = Rectangle.Empty;
barRect.Width = WidthOfBar - 1;
int barYPos = -1;
using (Pen barPen = new Pen(functionColor))
{
for (int i = FirstVisibleItemIndex, k = 0; i < _indexLimit; i++, k++)
{
if (base.GetBarEndPosition(k) > Width)
return;
BarPositions.Add(GetTickPosition(k));
if (i < functionValues.Length)
barYPos = functionValues[i];
else
continue;
//barRect = new Rectangle();
barRect.X = barXPos;
barRect.Y = barYPos;
//barRect.Width = WidthOfBar - 1;
barRect.Height = Height - barYPos;
g.DrawRectangle(barPen, barRect);
barXPos += (WidthOfBar + DistanceBetweenBars);
}
}
}
// drawing filled rectangles
private void DrawFilledRectangles(Graphics g, int[] functionValues, Color functionColor)
{
BarPositions = new List<int>();
int barXPos = FirstBarDrawPosition;
Rectangle barRect = Rectangle.Empty;
barRect.Width = WidthOfBar;
int barYPos = -1;
using (SolidBrush barBrush = new SolidBrush(functionColor))
{
for (int i = FirstVisibleItemIndex, k = 0; i < _indexLimit; i++, k++)
{
if (base.GetBarEndPosition(k) > Width)
return;
BarPositions.Add(GetTickPosition(k));
if (i < functionValues.Length)
barYPos = functionValues[i];
else
continue;
//barRect = new Rectangle();
barRect.X = barXPos;
barRect.Y = barYPos;
//barRect.Width = WidthOfBar;
barRect.Height = Height - barYPos;
g.FillRectangle(barBrush, barRect);
barXPos += (WidthOfBar + DistanceBetweenBars);
}
}
}
private void DrawStepLines(Graphics g, int[] lineData, Color lineColor)
{
BarPositions = new List<int>();
int lineYPos = -1;
int barXPos = FirstBarDrawPosition;
using (Pen linePen = new Pen(lineColor, 2.0f))
{
for (int i = FirstVisibleItemIndex, k = 0; i < _indexLimit; i++, k++)
{
if (base.GetBarEndPosition(k) > Width)
return;
BarPositions.Add(GetTickPosition(k));
if (i < lineData.Length)
lineYPos = lineData[i];
else
continue;
// draw third function line
//lineHeight = lineData[i];
g.DrawLine(linePen, barXPos, lineYPos, barXPos + WidthOfBar - 1, lineYPos);
barXPos += (WidthOfBar + DistanceBetweenBars);
}
}
}
我正在使用绘制顺序和形状，如步线，直线，框架矩形（只是矩形）和矩形填充矩形。
由于性能关键应用，我想知道绘制这些形状的最快方法。
提前感谢任何建议。
答案 0 :(得分：3)
你熟悉双缓冲吗？保持屏幕外图像缓冲区以便在更改进入时进行写入。然后重写OnPaint以在一个语句中对整个图像进行blit。此外，使用no-op覆盖OnPaintBackground以消除在每个绘制上将控件清除为其背景颜色的默认行为。
旧的山丘，但here是关于在Compact Framework中使用GDI的一些最佳实践的文章。