入行已经7,8年了,一直想做一套漂亮点的自定义控件,于是就有了本系列文章。
GitHub:https://github.com/kwwwvagaa/NetWinformControl
码云:https://gitee.com/kwwwvagaa/net_winform_custom_control.git
Install-Package HZH_Controls
https://www.cnblogs.com/bfyx/p/11364884.html
注意观察各个控件交叠的地方,是不是发现他们没有遮挡?这就是这个控件的妙处了。
先说明一下这个控件的作用,很多时候我们需要一个图片类型的控件,但是有需要密集的放在一起,如果单纯的设置背景图或image的话 交叠在一起的部分就会存在遮挡现象,所有就有了这个控件。
该控件可以根据设置的采样图片来裁剪有用的绘图区域,这样的好处就是在交叠的时候,无用区域不会遮挡。
这个用GDI+画的,另外也用到了一点三角函数,不明白的话 可以先百度下
添加一个类UCSampling ,继承UserControl
添加属性
1 /// <summary>
2 /// The sampling imag
3 /// </summary>
4 private Bitmap samplingImag = null;
5 /// <summary>
6 /// Gets or sets the sampling imag.
7 /// </summary>
8 /// <value>The sampling imag.</value>
9 [Browsable(true), Category("自定义属性"), Description("采样图片"), Localizable(true)]
10 public Bitmap SamplingImag
11 {
12 get { return samplingImag; }
13 set
14 {
15 samplingImag = value;
16 ResetBorderPath();
17 Invalidate();
18 }
19 }
20
21 /// <summary>
22 /// The transparent
23 /// </summary>
24 private Color? transparent = null;
25
26 /// <summary>
27 /// Gets or sets the transparent.
28 /// </summary>
29 /// <value>The transparent.</value>
30 [Browsable(true), Category("自定义属性"), Description("透明色,如果为空,则使用0,0坐标处的颜色"), Localizable(true)]
31 public Color? Transparent
32 {
33 get { return transparent; }
34 set
35 {
36 transparent = value;
37 ResetBorderPath();
38 Invalidate();
39 }
40 }
41
42 /// <summary>
43 /// The alpha
44 /// </summary>
45 private int alpha = 50;
46
47 /// <summary>
48 /// Gets or sets the alpha.
49 /// </summary>
50 /// <value>The alpha.</value>
51 [Browsable(true), Category("自定义属性"), Description("当作透明色的透明度,小于此透明度的颜色将被认定为透明,0-255"), Localizable(true)]
52 public int Alpha
53 {
54 get { return alpha; }
55 set
56 {
57 if (value < 0 || value > 255)
58 return;
59 alpha = value;
60 ResetBorderPath();
61 Invalidate();
62 }
63 }
64
65 /// <summary>
66 /// The color threshold
67 /// </summary>
68 private int colorThreshold = 10;
69
70 /// <summary>
71 /// Gets or sets the color threshold.
72 /// </summary>
73 /// <value>The color threshold.</value>
74 [Browsable(true), Category("自定义属性"), Description("透明色颜色阀值"), Localizable(true)]
75 public int ColorThreshold
76 {
77 get { return colorThreshold; }
78 set
79 {
80 colorThreshold = value;
81 ResetBorderPath();
82 Invalidate();
83 }
84 }
85
86 /// <summary>
87 /// The bit cache
88 /// </summary>
89 private Bitmap _bitCache;
在大小改变或图片改变时重新计算边界
1 /// <summary>
2 /// The m border path
3 /// </summary>
4 GraphicsPath m_borderPath = new GraphicsPath();
5
6 /// <summary>
7 /// Handles the SizeChanged event of the UCSampling control.
8 /// </summary>
9 /// <param name="sender">The source of the event.</param>
10 /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
11 void UCSampling_SizeChanged(object sender, EventArgs e)
12 {
13 ResetBorderPath();
14 }
15
16 /// <summary>
17 /// Resets the border path.
18 /// </summary>
19 private void ResetBorderPath()
20 {
21 if (samplingImag == null)
22 {
23 m_borderPath = this.ClientRectangle.CreateRoundedRectanglePath(5);
24 }
25 else
26 {
27 var bit = new Bitmap(this.ClientRectangle.Width, this.ClientRectangle.Height);
28 using (var bitg = Graphics.FromImage(bit))
29 {
30 bitg.DrawImage(samplingImag, this.ClientRectangle, 0, 0, samplingImag.Width, samplingImag.Height, GraphicsUnit.Pixel);
31 }
32 _bitCache = bit;
33 m_borderPath = new GraphicsPath();
34 List<PointF> lstPoints = GetBorderPoints(bit, transparent ?? samplingImag.GetPixel(0, 0));
35 m_borderPath.AddLines(lstPoints.ToArray());
36 m_borderPath.CloseAllFigures();
37 }
38 }
39
40 /// <summary>
41 /// Gets the border points.
42 /// </summary>
43 /// <param name="bit">The bit.</param>
44 /// <param name="transparent">The transparent.</param>
45 /// <returns>List<PointF>.</returns>
46 private List<PointF> GetBorderPoints(Bitmap bit, Color transparent)
47 {
48 float diameter = (float)Math.Sqrt(bit.Width * bit.Width + bit.Height * bit.Height);
49 int intSplit = 0;
50 intSplit = (int)(7 - (diameter - 200) / 100);
51 if (intSplit < 1)
52 intSplit = 1;
53 List<PointF> lstPoint = new List<PointF>();
54 for (int i = 0; i < 360; i += intSplit)
55 {
56 for (int j = (int)diameter / 2; j > 5; j--)
57 {
58 Point p = GetPointByAngle(i, j, new PointF(bit.Width / 2, bit.Height / 2));
59 if (p.X < 0 || p.Y < 0 || p.X >= bit.Width || p.Y >= bit.Height)
60 continue;
61 Color _color = bit.GetPixel(p.X, p.Y);
62 if (!(((int)_color.A) <= alpha || IsLikeColor(_color, transparent)))
63 {
64 if (!lstPoint.Contains(p))
65 {
66 lstPoint.Add(p);
67 }
68 break;
69 }
70 }
71 }
72 return lstPoint;
73 }
74
75 /// <summary>
76 /// Determines whether [is like color] [the specified color1].
77 /// </summary>
78 /// <param name="color1">The color1.</param>
79 /// <param name="color2">The color2.</param>
80 /// <returns><c>true</c> if [is like color] [the specified color1]; otherwise, <c>false</c>.</returns>
81 private bool IsLikeColor(Color color1, Color color2)
82 {
83 var cv = Math.Sqrt(Math.Pow((color1.R - color2.R), 2) + Math.Pow((color1.G - color2.G), 2) + Math.Pow((color1.B - color2.B), 2));
84 if (cv <= colorThreshold)
85 return true;
86 else
87 return false;
88 }
1 #region 根据角度得到坐标 English:Get coordinates from angles
2 /// <summary>
3 /// 功能描述:根据角度得到坐标 English:Get coordinates from angles
4 /// 作 者:HZH
5 /// 创建日期:2019-09-28 11:56:25
6 /// 任务编号:POS
7 /// </summary>
8 /// <param name="angle">angle</param>
9 /// <param name="radius">radius</param>
10 /// <param name="origin">origin</param>
11 /// <returns>返回值</returns>
12 private Point GetPointByAngle(float angle, float radius, PointF origin)
13 {
14 float y = origin.Y + (float)Math.Sin(Math.PI * (angle / 180.00F)) * radius;
15 float x = origin.X + (float)Math.Cos(Math.PI * (angle / 180.00F)) * radius;
16 return new Point((int)x, (int)y);
17 }
18 #endregion
取边界的思路如下:
1,以控件中心为原点,按照一定的角度顺时针依次进行旋转,
2、每次旋转后,按照此角度从外向内,找到第一个不是透明的点记录下来,这就是外边界点
这个取边界算法感觉并不是太好,如果哪位小伙伴有更好的算法,希望可以探讨一下
重绘
1 protected override void OnPaint(PaintEventArgs e)
2 {
3 base.OnPaint(e);
4 e.Graphics.SetGDIHigh();
5
6 this.Region = new System.Drawing.Region(m_borderPath);
7
8 if (_bitCache != null)
9 e.Graphics.DrawImage(_bitCache, 0, 0);
10
11 }
如果你喜欢的话,请到 https://gitee.com/kwwwvagaa/net_winform_custom_control 点个星星吧