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nmake



Joined: 13 Sep 2012
Posts: 192
nmake 21 Feb 2013, 09:12
I'm not very familiar with fasm macros, I try to keep regularly used and important facts in an everygrowing note.

How can I repeat something using either repeat or rept and increase a floating point number without having to resort to complex int to string macros. I have this direct3d program and I need to duplicate several cube sections to make up a very long corridor, and I use floating point constants to position the cubes, how can I repeat something and add 2.0 to the constant on each iteration?

I guess I have to use some form of int to string macros and then pad .0 to it?
Post 21 Feb 2013, 09:12
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr 21 Feb 2013, 11:04
nmake,

Preprocessor operates with symbols (though it recognizes them as numbers when needs to). For simple cases it can help: rept 10 i:0 { dd 2#i#.0 } will generate equivalent of dd 20.0, 21.0, ..., 29.0. More generic cases probably will require assembly stage to perform compile-time floating point processing (preprocessor can join symbols but can't split them, at least directly, AFAIK).

Explain your problem, maybe it can be solved.
Post 21 Feb 2013, 11:04
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nmake



Joined: 13 Sep 2012
Posts: 192
nmake 21 Feb 2013, 11:32
My simple problem is that I need to add 2.0 to a floating point immediate parameter that I pass to a function. Thats the whole simple problem.
Code:
invoke function,2.0    

now, invoke the same function, but with 4.0 next time, then 6.0 next time, then 8.0 next time. Repeat this 20 times over.

I used runtime floating point calculation to temporary solve it, it was just for testing purposes, building a very large stone corridor.

http://i.imgur.com/tNvDPkC.jpg
Post 21 Feb 2013, 11:32
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr 21 Feb 2013, 13:21
nmake,

Preprocessor can perform compile-time calculations.
Code:
rept 20 % {
  rept 1 %%: %*2 \{
    invoke function, %%\#f
  \}
}    
Why don't use a loop?
Post 21 Feb 2013, 13:21
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nmake



Joined: 13 Sep 2012
Posts: 192
nmake 21 Feb 2013, 13:36
Yes, I forgot about the escape characters.
Post 21 Feb 2013, 13:36
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