Tile based "digging" games

Many of you have probably seen games like terraria for example where the terrain seems to be made up of tiles that you can dig out.

I was wondering what the theory behind the creation is?

Are the tiles little sprites that you spread all over the screen?

I'm gathering you wouldn't paint them by hand and that you would generate them some how? I guess this would involve setting an upper limit (so you have a horizon) and then getthing it to fill in the test with sprites and adding a random function somewhere to pick different types of sprites.

Is that sounding like a sane path to take?
Any options or examples welcome.

For a start of an answer check this post out
There are also other examples of tiling/grid in the "how do I" section, make sure to do a quick search if you need more.

Very nice so one method is to store the differing tile images as animations as use something like int(Random(0,Sprite.AnimationFrameCount)) to pick a random animation. That's cool. If you wanted to "tile" around something. E.g. bury a diamond in the dirt I guess you could overlap the diamond at a particular position on another layer then when you grab it you could destroy all the overlapping tiles so you have a hole where it was dug out?

I also may add that for awesomely big world, you could use random seed.

The idea behind that is that all number returned by this kind of random() function would always take your seed number at a start and return every time the same numbers.
Because you might not now it but a random doesn't really exists in a computer world. Random() function are series. You take a starting number and then always apply the same operation to have the next pseudorandom number.
Well now that I've explained that for those who didn't know.
If you apply the same random operation for creating your big world, you can understand now that if you have the same serie of randome number you'll generate the same exact world.

Then basically you could store an entire world in one single number (and I believe it's how minecraft works). Then you just have to store what has been modified in this world. Which would be far less than the big world.
The only downside is that generating the world, if it's a really big one, could take some time.
But there's some ways to split your big world in tiny ones (that's the purpose of Arsonide's gridTree plugin for Construct Classic) to avoid this overhead (also minecraft might use something like that).

That's all (:

Edited by Yann - 11 Jan 2012 at 10:41am

Terraria you say..yes excellent game but Ummmm....
What about "Cortex Command"..Sheer Genius..A Brilliant Indy game... 11 years in the making...

The only way I can think how they did it was with an Procedurally generated Pixel Array of Truly EPIC Dimensions

well worth a look...if you can figure how they made that and give me that code ..I'll buy you a Lamborghini ....A phat red one



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