要绘制旋转的Bitmap，您需要做几个步骤来准备 Graphics 对象:

To draw a rotated Bitmap you need to do a few steps to prepare the Graphics object:

• 首先将其原点移动到旋转的中点
• 然后旋转所需的角度
• 接下来将其移回
• 现在您可以绘制Bitmap
• 最后你重置了Graphics

这需要为每个位图完成.

This needs to be done for each bitmap.

以下是在 (xPos, yPos) 位置绘制 Bitmap bmp 的代码步骤:

Here are the steps in code to draw a Bitmap bmp at position (xPos, yPos):

float moveX = bmp.Width / 2f + xPos;   
float moveY = bmp.Height / 2f+ xPosf;   
e.Graphics.TranslateTransform(moveX , moveY );
e.Graphics.RotateTransform(angle);
e.Graphics.TranslateTransform(-moveX , -moveY );
e.Graphics.DrawImage(bmp, xPos, yPos);  
e.Graphics.ResetTransform();

有一种可能的复杂情况:如果您的 Bitmap 具有与屏幕不同的 dpi 分辨率，即与 Graphics 不同，您必须首先调整 dpicode>Bitmap的dpi设置！

There is one possible complication: If your Bitmap has different dpi resolution than the screen i.e. than the Graphics you must first adapt the Bitmap's dpi setting!

要使 Bitmap 适应通常的 96dpi，您只需执行

To adapt the Bitmapto the usual 96dpi you can simply do a

bmp.SetResolution(96,96);

为了为将来的类似视网膜显示做好准备，您可以创建一个在启动时设置的类变量:

To be prepared for future retina-like displays you can create a class variable you set at startup:

int ScreenDpi = 96;
private void Form1_Load(object sender, EventArgs e)
{
  using (Graphics G = this.CreateGraphics()) ScreenDpi = (int)G.DpiX;
}

并在加载Bitmap后使用:

bmp.SetResolution(ScreenDpi , ScreenDpi );

像往常一样，DrawImage 方法使用Bitmap 的左上角.您可能需要为旋转点使用不同的 Points，也可能需要为您的汽车的虚拟位置使用不同的 Points，也许在它的前部中间..

As usual the DrawImage method uses the top left corner of the Bitmap. You may need to use different Points for the rotation point and possibly also for the virtual position of your car, maybe in the middle of its front..