C# 图像旋转 例子 代码
图像旋转的C#示例:
private void RotateTransform_Click(object sender, System.EventArgs e)
{
Graphics graphics=this.CreateGraphics();
graphics.Clear(Color.White);
//装入图片
Bitmap image=new Bitmap("nemo.bmp");
//获取当前窗口的中心点
Rectangle rect=new Rectangle(0,0,this.ClientSize.Width,this.ClientSize.Height);
PointF center=new PointF(rect.Width/2,rect.Height/2);
float offsetX=0;
float offsetY=0;
offsetX=center.X-image.Width/2;
offsetY=center.Y-image.Height/2;
//构造图片显示区域:让图片的中心点与窗口的中心点一致
RectangleF picRect=new RectangleF(offsetX,offsetY,image.Width,image.Height);
PointF Pcenter=new PointF(picRect.X+picRect.Width/2,
picRect.Y+picRect.Height/2);
//让图片绕中心旋转一周
for(int i=0;i<361;i+=10)
{
// 绘图平面以图片的中心点旋转
graphics.TranslateTransform(Pcenter.X, Pcenter.Y);
graphics.RotateTransform(i);
//恢复绘图平面在水平和垂直方向的平移
graphics.TranslateTransform(-Pcenter.X, -Pcenter.Y);
//绘制图片并延时
graphics.DrawImage(image,picRect);
Thread.Sleep(100);
//重置绘图平面的所有变换
graphics.ResetTransform();
}
}
private static int MyAngle = 0; //旋转角度[-360,360]
private void Page_Load(object sender, EventArgs e)
{
Image img;
FileStream fs;
fs = new FileStream(IMAGEFILE, FileMode.Open, FileAccess.Read);
img = Bitmap.FromStream(fs);
fs.Close();
pictureBox1.Image = img;
}
private void button1_Click(object sender, EventArgs e)
{
MyAngle = 90;
//MyAngle += 90;
//if (MyAngle > 360) MyAngle = 90;
pictureBox1.Image = RotateImg(GetSourceImg(IMAGEFILE), MyAngle);
}
private void button2_Click(object sender, EventArgs e)
{
MyAngle = -90;
//MyAngle += -90;
//if (MyAngle < -360) MyAngle = -90;
//pictureBox1.Image = RotateImg(Bitmap.FromFile(IMAGEFILE), MyAngle);
pictureBox1.Image = RotateImg(IMAGEFILE, MyAngle);
}
#region 图片旋转函数
/// <summary>
/// 以逆时针为方向对图像进行旋转
/// </summary>
/// <param name="b">位图流</param>
/// <param name="angle">旋转角度[0,360](前台给的)</param>
/// <returns></returns>
public Image RotateImg(Image b, int angle)
{
angle = angle % 360;
//弧度转换
double radian = angle * Math.PI / 180.0;
double cos = Math.Cos(radian);
double sin = Math.Sin(radian);
//原图的宽和高
int w = b.Width;
int h = b.Height;
int W = (int)(Math.Max(Math.Abs(w * cos - h * sin), Math.Abs(w * cos + h * sin)));
int H = (int)(Math.Max(Math.Abs(w * sin - h * cos), Math.Abs(w * sin + h * cos)));
//目标位图
Bitmap dsImage = new Bitmap(W, H);
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(dsImage);
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.Bilinear;
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//计算偏移量
Point Offset = new Point((W - w) / 2, (H - h) / 2);
//构造图像显示区域：让图像的中心与窗口的中心点一致
Rectangle rect = new Rectangle(Offset.X, Offset.Y, w, h);
Point center = new Point(rect.X + rect.Width / 2, rect.Y + rect.Height / 2);
g.TranslateTransform(center.X, center.Y);
g.RotateTransform(360 - angle);
//恢复图像在水平和垂直方向的平移
g.TranslateTransform(-center.X, -center.Y);
g.DrawImage(b, rect);
//重至绘图的所有变换
g.ResetTransform();
g.Save();
g.Dispose();
//保存旋转后的图片
b.Dispose();
dsImage.Save("FocusPoint.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
return dsImage;
}
public Image RotateImg(string filename, int angle)
{
return RotateImg(GetSourceImg(filename), angle);
}
public Image GetSourceImg(string filename)
{
Image img;
img = Bitmap.FromFile(filename);
return img;
}
#endregion 图片旋转函数
有代码吗？
木有
可是看看书考试科目都没苦思苦想，们多么开始，
