How to create a growwing dot line ?

In my free time, i am working on video clip of a band, they have song about a murder case.
Now the story goes that he’s daily mudering people in a small city.
A bit like a folk story line, but the band is more a retro 70’s punk/rock band they sound like siouxsie and the banshees

For their lyric story the’ve drawn a fictional city map, wich i colored digital, and next I will use Blender camera tracking to “walk” over the map. Its all 2D from top, turning and zooming etc. (there is no 3d stuff for this needed)

But i wonder would it be possible that while the camera is folowing the path, that a dotted line emerges folowing the same camera track. ( like we have unknown killer detective dots on a map without showing a person ).
The dots should stay in place (not stretch) … maybe particles… or something else ?

Putting in small dots objects one by one manualy, is not realy on option.
Their drawing is like 124 x 86 cm the mpa image i’ will be using is roughly about 11000x7000 pixels .

It doesnt matter to me if the dots are round or stretched blocks, but once placed they should stay, and not resize.

This final movie might be done in BI, CYCLES, or most likely will be OpenGL rendered, since its not about 3D but its more about camera tracking over a Map, which only Blender is able to do.
But if the trick can only be done using a certain render then i will use that.

you need the ‘dynamic paint’ modifier. you designate one mesh as your brush, and another as your canvas, animate, and it makes your animated texture.

Curve and circle, animate dupliframe end value from 0 to end.

Wit dupliframe how do i get my dots seperated ? (i’m now getting a snake form of connected dots)

Set Duplication > Frames > Off value higher than 1 and find a good distribution.

Drivers, path, array. http://www.pasteall.org/blend/34785

thanks for the file, i had too much setting conflicting i think in my old file, i removed it and set it up like that and now it works.
and i like it,

Now as in the lyric there is killer in the city of bloodvile, and the dots mark his movement but his identity is unknown.
which is better then creating a 2D murderer and move it on the map. (he remains better unknown as in the song).
In the song its not clearly a male or female, and a police inspector tries to trace him.

I read this ^ and think Sin City…