//occurs when user moves mouse
//will record most recent location of mouse, and call drawing function
private void SignaturePanel_MouseMove(object sender, MouseEventArgs e)
{
if (isDown)
{
Point point = SignaturePanel.PointToClient(Cursor.Position);
newX = point.X; newY = point.Y;
DrawLine();
}
}
//draws a line on user's screen between most recent mouse position, and second most recent
//then updates second most recent position
public void DrawLine()
{
if (oldX != -1 && oldY != -1)
{
Graphics g = SignaturePanel.CreateGraphics();
Pen pen = new Pen(Color.Black);
g.DrawLine(pen, newX, newY, oldX, oldY);
}
oldX = newX;
oldY = newY;
}
