C# drawing and invalidating 2 lines to meet
- by BlueMonster
If i have 2 lines on a page as such:
e.Graphics.DrawLine(blackPen, w, h, h, w);
e.Graphics.DrawLine(blackPen, w2, h2, h2, w2);
how would i animate the first line to reach the second line's position?
I have the following method which calculates the distance between two points (i'm assuming i would use this?)
public int Distance2D(int x1, int y1, int x2, int y2)
{
// ______________________
//d = √ (x2-x1)^2 + (y2-y1)^2
//
//Our end result
int result = 0;
//Take x2-x1, then square it
double part1 = Math.Pow((x2 - x1), 2);
//Take y2-y1, then sqaure it
double part2 = Math.Pow((y2 - y1), 2);
//Add both of the parts together
double underRadical = part1 + part2;
//Get the square root of the parts
result = (int)Math.Sqrt(underRadical);
//Return our result
return result;
}
How would i re-draw the line (on a timer) to reach the second line's position? I've looked a lot into XAML (story-boarding) and such - but i want to know how to do this on my own. Any ideas? I know i would need a method which runs in a loop re-drawing the line after moving the position a tid bit. I would have to call Invalidate() in order to make the line appear as though it's moving... but how would i do this? how would i move that line slowly over to the other line? I'm pretty sure i'd have to use double buffering if i'm doing this as well... as such:
SetStyle(ControlStyles.DoubleBuffer | ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint, true);
This doesn't quiet work, i'm not quiet sure how to fix it. Any ideas?
protected override void OnPaint(PaintEventArgs e)
{
Distance2D(w, h, w2, h2);
if (w2 != w && h2 != h)
{
e.Graphics.DrawLine(blackPen, (w * (int)frame), (h * (int)frame), (h * (int)frame), (w * (int)frame));
e.Graphics.DrawLine(blackPen, w2, h2, h2, w2);
}
else
{
t.Abort();
}
base.OnPaint(e);
}
public void MoveLine()
{
for (int i = 0; i < 126; i++)
{
frame += .02;
Invalidate();
Thread.Sleep(30);
}
}
private void button1_Click(object sender, EventArgs e)
{
t = new Thread(new ThreadStart(MoveLine));
t.Start();
}
