How the get the integers that enclose a float value?

Scripting
1

Hi!, I want to know how to determine through code which integers enclose a float value. E.g a variable stores the float 8.33, I want to know which two integers encloses the value 8.33 and store them in two variables

Now suppose I already know these integers (in this case 8 and 9). Then i use this two integers to read the values stored in an int array at those positions. Position 8 stores the int 84 and position 9 stores 76. What I want to know is how to interpolate the values that are stored at the respective positions, achieving a value that approximate to what should be the float between the two integers, in this case 8.33, all this through code. E.g. if pos 8 stores 84 and pos 9 stores 76, 8.33 should return a value of 81.36.

Any help is appreciated, thanks!

2

Something like this, if I understood correctly.

float value = 8.33f;

int floor = Mathf.FloorToInt(value);
int ceil = Mathf.CeilToInt(value);

int a = array[floor];
int b = array[ceil];

float result = Mathf.Lerp(a, b, value % 1.0f);

FloorToInt rounds down to an integer, giving 8.
CeilToInt rounds up to an integer, giving 9.
Lerp does the interpolation between a and b using value % 1.0f as the percentage.
value % 1.0f gives the fractional component of the number (0.33).

1 Like
3

Just be careful when using the remainder operator on negative numbers, it will give incorrect result.

EDIT: OP is using values as array indices, so they are probably positive, but I will leave my comment here just in case.

1 Like
4

It is exactly what i was looking for, thanks a lot!

That’s good to know, although i dont think its gonna cause any problems because the float as well as the values stored in the array should be always positive. Thanks for the info!