Terrain map sizes

In general how big of a terrain map have you been able to create in regards to the size of the actual height and terrain images.

reason being, I would like to create some really large terrains, which i have done by scaling the terrain to a larger size, but as you do that the actual graphics of the terrain look more blurred and obscure. Right now im using 256x256 would increasing the size to 512x512 or 1024x1024 make big hits in fps?

Rob

Hi. I'm using a 1024x1024 bmp (both height and coloured overlay).
I scale (x and z) times 20.
And yes, there is a big fps hit - but I live with it 'cause like you I need a HUGE terrain.
I think it's OK, but you will need to play with terrain detail to tweak it.
The trouble is that now I am adding trees, houses,fire and smoke sprites, the fps can be as slow as 9/sec on a slow card.
I am actually beginning to suspect that the sprites (trees/fire/smoke) have the biggest hit.
Anyone like to comment?
- John

I'm not really sure why scaling a terrain would cause any speedhit. The same amount of vertices are being processed no matter what the size. I suspect you're right about the other objects (especially if you're not combining them into single surface entities!) being the largest cause of the slowdown.