Tiny Function to unsign a byte from READBYTE value

[spicypixel]

I'd written a simple map editor in BlitzPlus which writes out my mapdata as Bytes and when I read it into GLB the values are in the range -127...+127 and I needed them in the range 0...255. Here is a quick and easy way to do that which although not rocket science does help keep your code looking cleaner.

Function Code

Code (glbasic) Select Expand


// .------------------------------------.
// |  Unsign READBYTE value to 0...255  |
// `------------------------------------'
FUNCTION UnsignByte: value%
IF value% < 0 THEN value% = 256 + value%
RETURN value%
ENDFUNCTION

Usage

Code (glbasic) Select Expand

signed_byte% = UnsignByte(signed_byte%)

Hope you find it useful

[Moebius]

Nice - but look up READUBYTE in the docs 

[spicypixel]

Noob alert here lol. I guess it's still handy for poeple to see how it's converted even though maybe I should read the docs more next time

[Moebius]

I only noticed because someone else posted about it a while ago 

[Ian Price]

I think we've all been caught out by that one in the past, especially us old Blitz users.

[Moru]

Yep, I'm the original one that got caught out with the problem of reading bytes from a file, Thanks Gernot for fixing it so fast back then :-)

[spicypixel]

Yep, I'm the original one that got caught out with the problem of reading bytes from a file, Thanks Gernot for fixing it so fast back then :-)

Hehe guess we won't be the first, OR the last lol