Transformations to extract an image of an arbitrary line

private Bitmap ExtractLaneImage(Image source, DetectorLane lane) {
    // Find the bounding recatangle and offset to the start
    Point topLeft = new Point(Math.Min(lane.start.X, lane.end.X), Math.Min(lane.start.Y, lane.end.Y));
    Point bottomRight = new Point(Math.Max(lane.start.X, lane.end.X), Math.Max(lane.start.Y, lane.end.Y));
    Size size = new Size(bottomRight.X - topLeft.X, bottomRight.Y - topLeft.Y);
    Rectangle area = new Rectangle(topLeft, size);
    Point offset = new Point(topLeft.X - lane.start.X, topLeft.Y - lane.start.Y);

    // Find the lane angle (used for the rotation)
    Point delta = new Point(lane.end.X - lane.start.X, lane.end.Y - lane.start.Y);
    double angle = Math.Atan2(delta.Y, delta.X) * 180 / Math.PI;

    // Find the length of the line
    double length = Math.Sqrt(Math.Pow(size.Width, 2) + Math.Pow(size.Height, 2));

    // Create the image for this lane
    Bitmap image = new Bitmap((int)length, 20);
    Graphics g = Graphics.FromImage(image);

    // Centre point/drawing position
    Point position = new Point(0, image.Height / 2);

    // Default white fill
    g.FillRectangle(Brushes.White, new Rectangle(new Point(0, 0), image.Size));

    // Offset to get start point at the desired position
    g.TranslateTransform(offset.X, offset.Y, MatrixOrder.Append);

    // Rotate (adjusting to to origin and back)
    g.TranslateTransform(-position.X, -position.Y, MatrixOrder.Append);
    g.RotateTransform(-(float)angle, MatrixOrder.Append);
    g.TranslateTransform(position.X, position.Y, MatrixOrder.Append);

    // Draw the final image
    g.DrawImage(source, position.X, position.Y, area, GraphicsUnit.Pixel);

    g.Dispose();
    return image;
}