setting a variable to = width/2 or height/2?

Programming Questions

novellof

setting a variable to = width/2 or height/2?

in Programming Questions • 1 year ago

when ever i set a variable lets say x = width and y=height/2 ......well it never freaking works....why?

for example:

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void setup() {
size(800,600);
}
int x = width/2;
int y = height/2;
void draw() {
ellipse(x,y,50,50);
}

the ellipse will not show up in the middle of the screen for me but if i do :

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void setup() {
size(800,600);
}
//int x = width/2;
//int y = height/2;
void draw() {
ellipse(width/2,height/2,50,50);
}

the ellipse shows up in the middle of the screen....

whyyy??

Replies(1)

amnon.owed

Re: setting a variable to = width/2 or height/2?

1 year ago

This is due to the order the program is run. First the global variables are set, then setup() once, then draw() continuously. At the time of setting the global variables x and y, the values for width and height have not yet been set. The width and height are set in setup() via the size call. So you can solve your problem by setting x and y in setup() after the width and height have been set.

Adapted Code

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int x, y; // here width and height are not yet set
void setup() {
size(800, 600); // here width and height are set
x = width/2; // now you can use width and height
y = height/2;
}
void draw() {
ellipse(x, y, 50, 50); // here you could also use width and height
}

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