Comparing two values from different vectors: Not working

Unity Engine
1

Hi,

Could someone please help me to understand why if I compare 2 values (“x” values ) from two different vectors (one Vector2 and the other Vector4), even they are equal (0,8 for example) Unity considers they are different?

This is part of the code:

private Vector2 newOffset;
private Vector4 animationLimits;
private float totalCol;
private float walkAnimationMin = 5;
private float walkAnimationMax = 14;
private float tempValue;
private Vector2 newOffset;  
private Vector2 currentOffset;


textureScale = gameObject.renderer.material.mainTextureScale;
totalCol = Mathf.Abs(1 / textureScale.x);
totalRow = Mathf.Abs(1 / textureScale.y);


tempValue = walkAnimationMax / totalCol;
animationLimits.z = Mathf.Sign(textureScale.x) * (tempValue - Mathf.Floor(tempValue));

.....

currentOffset = gameObject.renderer.material.mainTextureOffset;
newOffset.x = currentOffset.x + textureScale.x;

if (newOffset.x > animationLimits.z){
	...
}

Sorry if it is too confusing. Basically I am following the tutorial about Evac City and I am modifying the script for animating the player, for learning purpose.

Thanks

2

The two values have to be totally identical, not just the first decimal place.

–Eric

3

Thanks Erick. This means, that even in the Debug.Log both values are equal (0,8 for example) Unity is adding some extra decimals when I made all that calculation?

Edit: I just did some test, like this:
Debug.Log(newOffset.x - animationLimits.z);

and even both values are in theory 0,8 the result is something E-08.

Why this happens? I made the calculation in my calculator and the results are both 0,8 without any extra decimal.

Thanks

Regards

4

Floating point math isn’t 100% exact.

–Eric

5

Never, ever, ever compare floating point numbers for equality. Always use an approximation function. Try Mathf.Approximately Unity - Scripting API: Mathf.Approximately

6

I’m trying to compare two vectors (vector3) and if use != or Mathf.Approximately the result is ever the exact same, ever false (T_T) xD

Some idea?

Edit: finally i have found a solution, isn’t very elegant but…works (^_^)

function CompararVec () : boolean
{
        // i only need to compare x and z
	if ( System.Math.Round(vecOrig.x, 1) == System.Math.Round(vecDest.x, 1) 
             System.Math.Round(vecOrig.z, 1) == System.Math.Round(vecDest.z, 1) )
		return true;
	else
		return false;
}
7

I try ,
Vector.Distance(pointa,pointb)<=0.1
,
it’s work and it is fast than,
Mathf.Approxmatelt(…

So I use,
Vector.Distance(pointa,pointb)<=0.1 , this type

1 Like