changing colors in tiles without re-rendering?

[Ravi]

Thanks for the reply Steve. The problem is little more complicated than 
just identifying an appropriate image editor.

After the tiles are made, imagemagic has no way to co-relate a block 
group with tile name. Also if two adjacent block groups are of same 
color, imagemagic would not know how to change one of them.

The solution, if at all possible, has to be something like this:
1. Render the shape files into image files for each block group. The 
area outside block group should be transparent in such images.
2. A program that when supplied with block group number and color finds 
appropriate image and colors it accordingly.
3. A program that takes all the images and generates square image tiles.

Only in this case I can avoid parsing/reading the shapefile over and 
over again. I wonder if anybody has done anything remotely similar to 
this or if anybody can think of a better way to do this.

Ravi



Steve Lime wrote:
> I would imagine ImageMagick can handle such a task... 
> 
> Steve
> 
>>>> Ravi <ravikapoor101 at GMAIL.COM> 1/3/2007 12:21:05 PM >>>
> I have a strange question. I am using block group shape files to render
> 
> map of US at all zoom levels. This is very processor intensive job. I 
> want to avoid rendering tiles every time I change data as it takes me 
> days to do so.
> 
> Is it possible that somehow I draw the block group shapes and then use
> 
> some image manipulation software to change color of each block group. 
> Essentially the point is to try to avoid processing shape files every 
> time and instead move the job to a image manipulation software which I
> 
> believe will result in significant time reduction.
> 
> I seriously doubt anything like this can be done but I decided to ask 
> anyways.
> 
> - Ravi
>