[pygame] Tile Size

[Kris Schnee]

I think that a 2D, flat scrolling tile system in Pygame would be a 
decent compromise between graphical quality and ease of programming, for 
my project. I can live with the game's islands being a constant height, 
for simplicity. One question I could use input on is about tile size.

Right now the game world has 100x100 "zones" representing chunks of 
terrain I imagine as 1 Km^2, ie. each data point represents a 10m^2 
area. I'd like to show human-sized figures, meaning you can see maybe 
ten times the player's width at a time -- maybe 10 meters across. For an 
800x600 screen, that would mean tiles maybe 80 pixels wide for each data 
point. Pre-drawing a whole zone then would mean blitting from a picture 
8000x8000 pixels in size! Is that impractical?

I'd like to use square tiles of some reasonable size, erring on the side 
of using a few big tiles. Maybe I should treat a zone as being just 
100x100m? The level of detail on the terrain itself doesn't need to be 
high, because objects like trees can be added separately at any exact 
coordinates. (That is, I could describe an island's shape with a small 
number of data points saying "water here, sand here, grass here" and 
then a list of exact positions for objects.)

Since the game has an island theme I would also like to draw water 
translucently, which would mean blitting a water texture (or at least 
translucent blue/cyan) over parts of the terrain, rather than just using 
blue tiles as I once did ( 
http://kschnee.xepher.net/pics/niss-051111.jpg ). That also means having 
some way to draw water "in front of" or "behind" sprites or even some of 
both depending on their vertical position, right? Even if the landscape 
is a constant height for drawing purposes, I'd still like to have a 
character able to go underwater, being drawn "behind" the water, but 
also able to be above it or at the surface. Drawing water could be done 
on the fly each frame, or given its own drawing plane -- doubling the 
RAM needed for the pre-drawing -- or even given a much smaller drawing 
plane and then somehow scaled up each frame. What method makes sense?

Kris