Initialising an array of addresses

Initialising an array of addresses - Printable Version

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Initialising an array of addresses - LTee - 2011-08-10

I was trying to keep a list of memory addresses (pointing to tile data) in an array to use as a cheap lookup table. I tried to do something like this:

Code:
'data

Data:

asm

defb 0, 0, 191, 191, 191, 191, 191, 191, 0, 0, 253, 253, 253, 253, 253, 253

end asm

'array of addresses

dim tsAddress(TSMAXTILES) as uinteger => {@Data}

... which doesn't work, because @Data isn't a constant so I get an "Initializer expression is not constant" compiler error.

I could write and call a method which loads the array with the correct information on startup, but I just wanted to check that I wasn't missing an obvious trick which would allow me to avoid that? Thanks for any tips! Smile

Re: Initialising an array of addresses - boriel - 2011-08-10

You can't do it that way, but you can simply put those bytes in 16bit format:

Code:
dim tsAddress(TSMAXTILES) as uinteger => {0 + 256 * 0, 191 + 256 * 191, 191 + 256 * 191, 191 + 256 * 191, 0 ...

or also

Code:
dim tsAddress(TSMAXTILES) as uinteger => {0x0000, 0xBFBF, 0xBFBF, 0xBFBF, 0x0000, ...

Note, BFBF = 191, 191 etc...

Re: Initialising an array of addresses - LTee - 2011-08-10

Ah, interesting! I'll give that a try, thanks boriel!