Special-Effect (Animate object drawing) question

Hi folks,

I would like to create a special effect and I was wondering how to approach this.

The effect seems to be quite simple: I would like to animate the drawing of a simple object (e.g. a bar, a line, a tube, a square) as one can see it in various SF films. First a (invicible) pen draws the lines of the floor, then the lines of the walls are drawn, finally the ceiling/top of the bar is drawn.

Additionally the lines are drawn in parallel by more than one (invicible) pen. Cool would also be to have a glowing effect a the point of the pen.

The architecture of the object is known in advance.

To be true I have no good idea how to approach this.

  • With scaling I can’t realize the visual effects I want to have.
  • One option would be to have something which makes the object partially invisible (like cutting it away) and the “drawing” is making the object visible gradually.
  • Manipulating the vertexes of the object?
    Any ideas/pointers?


hm… never really tried something like this. my first idea would’ve been to go thtough the vertexdata of a modell an change the alpha values of the single vertices… this wont really “draw” a line but would make it visible one by one (more or less). another idea is to sort the lines uv coordinates so they end up in a long long row and you could “draw” them by shifting the texture around.