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Index › Programming Questions & Help › Syntax Questions › Creating Variable Names
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Creating Variable Names (Read 305 times)
tschiggi
Creating Variable Names
Feb 19th, 2008, 1:05pm  
Hello!

I have a simple problem in calling the right variables.
My code looks similar to this:

array a[];
array b[];

if keyPressed = a { draw(a[] };
if keyPressed = b { draw(b[] };

void draw ( String choice) {
if ( choice.length <= 10 ) { ...

I know the code is completely wrong, but i hope you understand the problem. I simply want to tell the draw method the right array to work with.

Anyone knows help?

Greets
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dek
Re: Creating Variable Names
Reply #1 - Feb 19th, 2008, 2:07pm  
Here's a sketch off the top of my head, hope it helps.

Essentially, you have to check if and which key is being pressed. This way you can divert the program to either use one or the other array.


Quote:


// create the arrays
int[] big = new int[2];
int[] small = new int[2];

void setup() {
 size(200,200);
 background(0);
 noFill();
 stroke(255);
 rectMode(CENTER);

 // fill the arrays
 big[0] = 100;
 big[1] = 100;  
 small[0] = 10;
 small[1] = 10;

}

void draw() {
 background(0);

 if (keyPressed) {

   // if 'a' key is pressed
   if (key == 'a') {
     // draw using the first array
     rect(height/2,width/2,big[0],big[1]);
   }

   // if 'b' key is pressed
   if (key == 'b') {
     // draw using the second array
     rect(height/2,width/2,small[0],small[1]);
   }
 }
}
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tschiggi
Re: Creating Variable Names
Reply #2 - Feb 19th, 2008, 2:23pm  
Thaks for you reply!

I understand the code and will do it like this.
I thought there's a version with less code to pass the array name to a function which will use it to draw.

Greets
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dek
Re: Creating Variable Names
Reply #3 - Feb 19th, 2008, 2:54pm  
Sorry, I totally neglected that in my last sketch.

Check this out. It's does exactly the same as the previous sketch, but this time using the function call. In the function you have to define what value is being passed. So, in our case it's an int array.

Quote:


// create the arrays
int[] big = new int[2];  
int[] small = new int[2];  

void setup() {  
 size(200,200);  
 background(0);  
 noFill();  
 stroke(255);  
 rectMode(CENTER);  

 // fill the arrays
 big[0] = 100;  
 big[1] = 100;    
 small[0] = 10;  
 small[1] = 10;  
}  

void draw() {  
 background(0);  

 if (keyPressed) {  

   // if 'a' key is pressed
   if (key == 'a') {  
      //call drawing function and pass the first array
      drawarray(big);
   }  

   // if 'b' key is pressed
   if (key == 'b') {  
     //call drawing function and pass the second array
      drawarray(small);
   }  
 }  
}  

// draw whatever you want, using the passed array
void drawarray(int choice[]) {
rect(height/2,width/2,choice[0],choice[1]);
}

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tschiggi
Re: Creating Variable Names
Reply #4 - Feb 20th, 2008, 6:46pm  
Thanks for your help, everything works fine Wink

Greets
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