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Author Topic: Cross Platform float  (Read 2167 times)

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Foaly

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Cross Platform float
« on: June 12, 2012, 01:17:46 pm »
In config.hpp SFML defines a bunch of fixed-point data types in a cross-platform way (sf::Int16 etc.). I was wondering why are there no floating point data types (i.e. float or double)? I read somewhere that they are not consistent across all platforms either.

Laurent

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Re: Cross Platform float
« Reply #1 on: June 12, 2012, 02:00:07 pm »
The C++ standard doesn't define a specific encoding for floating point numbers, but on all the platforms that SFML supports you can expect floats to use the IEEE-754 representation with fixed sizes.
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Foaly

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Re: Cross Platform float
« Reply #2 on: June 12, 2012, 03:50:29 pm »
Meaing on windows, Mac and Linux float and double will always be the same size?

Laurent

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Re: Cross Platform float
« Reply #3 on: June 12, 2012, 04:02:50 pm »
Yes.
Laurent Gomila - SFML developer

Foaly

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Re: Cross Platform float
« Reply #4 on: June 12, 2012, 06:16:22 pm »
sweet thank you very much!

MorleyDev

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Re: Cross Platform float
« Reply #5 on: June 12, 2012, 06:25:41 pm »
I feel the need to note that long double will vary from compiler to compiler. On Visual Studio it's no different from a double (8 bytes in size), whilst on gcc it's typically 12 bytes (float is 4 and double is 8 ).
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Mario

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Re: Cross Platform float
« Reply #6 on: June 14, 2012, 11:11:36 am »
Also keep in mind that there might be different precision/rounding if you're using floats for anything that should stay in sync between platforms.