newb wrote on Oct 15^th, 2009, 11:54am:

Show us your best attempt, we might show what went wrong.

I was trying out this, and I get a message that it can't fint filter class or type, and I think I got why.

But how do I give the filter an value from the array "filt" ?
I was thinking I maby needed something like this in draw(),
filter(filt[intvalue?]);

If I could get that working then I hopefully can figure out how to change value.

I might be way off but this is what I could come up with, with my current knowledge of processing. :)

I will look into swith tomorrow, thanks for the tip.


int count = 0;
PImage[] pix = new PImage [3];


filter[] filt = new filter[3];

int x = 0;
int y = 0;

void setup(){

 filt[0] = filter(GRAY);
 filt[1] = filter(INVERT);
 filt[2] = filter(THRESHOLD);

 pix[0] = loadImage("filename.jpg");
 pix[1] = loadImage("filename2.jpg");
 pix[2] = loadImage("filename3.jpg");
 size(550,550);
 frameRate(60);
}

void draw(){  
 background(255);
 image(pix[count],x,y,550,550);
}

void keyPressed(){
 if(key == 32){
   count++;
 }
 if (count==3){
   count=0;
 }
 else if(key == 65 || key == 97){
   x+=3;
 }
}

Cedric is right.
filter(XXX) is a function call, not an object. It acts immediately on the sketch's display, you cannot store it. So you have to apply it in draw(), depending on current choice.
Otherwise, the overall logic is correct, with some little logic fixes:
Code:

void keyPressed(){
 if(key == 32){
   count++;
   [color=#ff0000]// Moved check inside test[/color]
   if (count==3){
     count=0;
   }
 }
 else if(key == 65 || key == 97){
   x+=3;
 }
} 

Note that you can write simpler (but slightly less readable, at least when you are not used to the idiom): count = ++count % 3;
So you get rid of the filter array, and in draw you do:
Code:

void draw(){  
 background(255);
 image(pix[count],x,y,550,550);
 switch (count) {
 // No case 0, I think it can be nice to see unfiltered image in this case
 case 1: filter(GRAY); break;
 case 2: filter(INVERT); break;
 case 3: filter(THRESHOLD); break;
 // and so on
 default:
 }
} 

Note the usage of break, to avoid applying the filters in cascade...