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Topic: Math for Converting values (Read 218 times) |
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Orkan Telhan
Guest
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Math for Converting values
« on: Jan 26th, 2004, 7:44am » |
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Another very newbie question:
How can one convert a value ranging from
(0,255) to (0,1)? And is there a function that does that?
thanks,
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TomC
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Re: Math for Converting values
« Reply #1 on: Jan 26th, 2004, 10:57am » |
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You need to divide by 255.
Be careful to make sure that your original value is a float, or converted to a float for the calculation. If you use an integer then values below 255 will get truncated to 0.
e.g.
Correct:
Code:
int value = 34;
float newValue = float(value) / 255;
println(newValue); // outputs 0.13333334
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Incorrect:
Code:
int value = 34;
float newValue = value / 255;
println(newValue); // outputs 0
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An alternative way to enforce the precision is to divide by 255.0f
e.g. for all the numbers between 0 and 255 inclusive,
Code:
for (int i = 0; i <= 255; i++) {
float value = i / 255.0f;
println(value);
}
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fry
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Re: Math for Converting values
« Reply #2 on: Jan 26th, 2004, 3:49pm » |
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a super tiny addition.. in processing you can also use:
float value = i / 255.0;
since it automatically adds in the 'f' for you. or in java you can use:
float value = i / 255f;
(unlike c/c++) so that it's easier to read than 255.0f;
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