我一直在尝试画一个 annulus (带厚度的环)在 C# 中带有透明孔和渐变边缘,但收效甚微。有人对如何执行此操作有任何建议吗?
这是一个不错的Blend Utility
这是最终结果 - 感谢 BlueMonkMN
Rectangle GetSquareRec(double radius, int x, int y)
{
double r = radius;
double side = Math.Sqrt(Math.Pow(r, 2) / 2);
Rectangle rec = new Rectangle(x - ((int)side), y - ((int)side), (int)(side * 2) + x, (int)(side * 2) + y);
return rec;
}
void Form1_Paint(object sender, PaintEventArgs e)
{
Graphics gTarget = e.Graphics;
gTarget.SmoothingMode = SmoothingMode.AntiAlias;
GraphicsPath pTemp = new GraphicsPath();
Rectangle r = GetSquareRec(200, 225, 225);
pTemp.AddEllipse(r);
pTemp.AddEllipse(GetSquareRec(50, 225, 225));
Color[] colors = new Color[5];
colors[0] = Color.FromArgb(192, 192, 192);
colors[1] = Color.FromArgb(105, 0, 0);
colors[2] = Color.FromArgb(169, 169, 169);
colors[3] = Color.FromArgb(0, 0, 0);
colors[4] = Color.FromArgb(0, 0, 0);
float[] positions = new float[5];
positions[0] = 0f;
positions[1] = 0.1f;
positions[2] = 0.35f;
positions[3] = 0.5f;
positions[4] = 1f;
ColorBlend Cb = new ColorBlend();
Cb.Colors = colors;
Cb.Positions = positions;
PathGradientBrush pgb = new PathGradientBrush(pTemp);
pgb.InterpolationColors = Cb;
pgb.CenterPoint = new PointF(r.X + (r.Width / 2), r.Y + (r.Height / 2));
gTarget.FillPath(pgb, pTemp);
}
最佳答案
这就是我在 Scrolling Game Development Kit 中的做法:
pTemp = new GraphicsPath();
pTemp.AddEllipse(Start.X, Start.Y, End.X - Start.X, End.Y - Start.Y);
pTemp.AddEllipse((Start.X * 3 + End.X) / 4f,
(Start.Y * 3 + End.Y) / 4f,
(End.X - Start.X) / 2f,
(End.Y - Start.Y) / 2f);
PathGradientBrush pgb = new PathGradientBrush(pTemp);
Blend b = new Blend();
b.Factors = new float[] { 0, 1, 1 };
b.Positions = new float[] { 0, .5F, 1 };
pgb.Blend = b;
pgb.CenterColor = ((SolidBrush)CurrentBrush).Color;
pgb.SurroundColors = new Color[] {CurrentPen.Color};
gTarget.FillPath(pgb, pTemp);
pgb.Dispose();
pTemp.Dispose();
(来源:enigmadream.com)
我为此示例编辑了原始 SGDK 代码,因为最初我不够聪明,无法缩放渐变以排除孔洞,但现在我想我是:)。
如果你希望看到这样的渐变:
(来源:enigmadream.com)
然后将混合代码更改为如下所示:
Blend blend = new Blend();
blend.Factors = new float[] { 0, 1, 0, 0 };
blend.Positions = new float[] { 0, 0.25F, .5F, 1 };
pgb.Blend = blend;
关于c# - 如何使用 GDI+ 绘制圆环( donut )?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/716984/