problems with float in java libgdx android

Question

ok i using libgdx for android game development and i have a AI which moves depending on value of variable "ENEMYSPEED". Initally the value is set as

static float EnemySPEED = 0.5f;

and everything works fine. so i perform a simply compute like this

EnemyVector.y -= EnemySPEED

Everything fine so far...

Now i feel my AI is moving fast and i decrease the variable value from 0.5f to 0.4f and i perform the same operation of decrement and it doesn't decrement!

What is going on??!!!

EDIT:

private void EnemyMove()
{
    EnemySection = findSection(Enemy);
    if(EnemySection == PlayerSection)
    {
        if(EnemyVector.x > PlayerVector.x) EnemyVector.x -= EnemySPEED;
        else if(EnemyVector.x < PlayerVector.x) EnemyVector.x += EnemySPEED;        
        else if(EnemyVector.y > PlayerVector.y) EnemyVector.y -= EnemySPEED;
        else if(EnemyVector.y < PlayerVector.y) EnemyVector.y += EnemySPEED;
    }
    else if(EnemySection == 1 ||EnemySection ==  3) EnemyVector.x += EnemySPEED;
    else if(EnemySection == 2 ||EnemySection ==  4) EnemyVector.x -= EnemySPEED;
    else if(EnemySection == 5)
    {
        if(EnemyVector.y > 212 || EnemyVector.y < 75)
        {
            if(PlayerSection == 1 ||PlayerSection ==  3) EnemyVector.x -= EnemySPEED;
            else if(PlayerSection == 2 ||PlayerSection ==  4) EnemyVector.x += EnemySPEED;  
        }
        else
        {
            if(PlayerSection == 1 ||PlayerSection ==  2) EnemyVector.y += EnemySPEED;
            else if(PlayerSection == 3 ||PlayerSection ==  4) EnemyVector.y -= EnemySPEED;
        }
    }

    if(Player.overlaps(Enemy)) System.out.println("Target Acquired!");  
    System.out.println(EnemyVector.x + "," + EnemyVector.y);
}

findSection finds in which quadrant the Enemy or player is in depending on parameter passed.

EDIT 2: i just noticed that it only works for 0.5,1,1.5 not any value in between. Is this some kind of limitation?

Please provide more contextual code. The above contains no errors. — Matt Clark
– Matt Clark, Commented Feb 23, 2014 at 7:55
I'm confused. Your "Everything is fine so far" and the change you make don't seem to make sense. If it's fine up until you perform the operation, it seems like you're saying -= increases the speed. But then why is everything fine? You also "feel", but is it actual? — ChiefTwoPencils
– ChiefTwoPencils, Commented Feb 23, 2014 at 7:56
IOW, feeling like it's faster is different than debugging the code and knowing it's faster. Debugging it, BTW, should clue you in on the happenings; no? — ChiefTwoPencils
– ChiefTwoPencils, Commented Feb 23, 2014 at 7:59
by faster literally what i meant is how much X's in XY co-ordinate it moves — wenn32
– wenn32, Commented Feb 23, 2014 at 8:00

wenn32 · Accepted Answer · 2014-02-23 08:29:19Z

1

Guys i am sorry the problem was with comparing two floats... :/

for example comparing 127.8 and 127.0 is obviously wont work.

i changed the code to this and it worked fine... don't know how i missed this.. lesson learned

Anyways thank you friends for your help..

if((int)EnemyVector.x > (int)PlayerVector.x) EnemyVector.x -= EnemySPEED;
        else if((int)EnemyVector.x < (int)PlayerVector.x) EnemyVector.x += EnemySPEED;      
        else if((int)EnemyVector.y > (int)PlayerVector.y) EnemyVector.y -= EnemySPEED;
        else if((int)EnemyVector.y < (int)PlayerVector.y) EnemyVector.y += EnemySPEED;

answered Feb 23, 2014 at 8:29

wenn32

1,3942 gold badges17 silver badges30 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Simon Groenewolt Over a year ago

Please mark your own answer as 'correct' so others will know you don't need an answer anymore.

Aman Agnihotri · Accepted Answer · 2014-02-23 08:06:01Z

0

Try and make the EnemySPEED as volatile. It might be the case that EnemySPEED is getting cached by the thread which is executing this code, and hence you are unable to see the difference when you change the EnemySPEED from 0.5 to 0.4.

answered Feb 23, 2014 at 8:06

Aman Agnihotri

3,0431 gold badge20 silver badges23 bronze badges

3 Comments

wenn32 Over a year ago

but EnemySPEED is not changed dynamically.. from beginning to the end of the game it doesn't change.

Aman Agnihotri Over a year ago

I thought that when you said that you decrease the variable value from 0.5 to 0.4, it meant dynamic decrement. :D

wenn32 Over a year ago

not i am sorry if i wasn't clear i just change the value and rebuild the project again

Collectives™ on Stack Overflow

problems with float in java libgdx android

2 Answers 2

1 Comment

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related