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Index › Programming Questions & Help › Syntax Questions › why need do it

void YaBB Newbies Offline Posts: 5	why need do it? May 2nd, 2009, 5:45am   when I do this "println(mouseX/width);" get the value always zero, but if I change to "println((float)mouseX/width);" then I can get the float value, why? I mean why need convert the mouseX? Is it default type as int? thx

PhiLho  YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: why need do it? Reply #1 - May 2nd, 2009, 6:53am   Indeed, the mouseX reference isn't explicit about its type. But well, mouse coordinates refers to pixels, so it makes sense it is an integer...

subpixel Senior Member Offline Posts: 261	Re: why need do it? Reply #2 - May 2nd, 2009, 9:06am   What PhiLho didn't mention is that an integer divided by an integer results in an integer, and since mouseX is something less than width, the result always rounds down to zero. Writing (float)mouseX is casting the integer as a float (rational number), and when you do the division the result is a float. -spxl
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void YaBB Newbies Offline Posts: 5	Re: why need do it? Reply #3 - May 2nd, 2009, 11:01am   cool! clearly answer, thx a lot