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Index › Programming Questions & Help › Programs › How could this work
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How could this work? (Read 571 times)
louisa.ivy
How could this work?
May 10th, 2009, 12:16am  
How could i get this image- the rabbit to move up, down and to the sides when a key is pressed? i know the key command in the reference but i don't know how to combine it to movements and the image

Thanks
louisa

PImage c;
void setup(){ size(900,800);
c=loadImage("Space-Rabbit.png");
smooth();
}

//ideas: have the rabbit jumping around to key presses.

void draw(){
 background(0);
 
 fill(255);//moon
noStroke();
ellipse(450,900,1000,900);
noFill();

image(c,300,195,180,380);//Rabbit
println(c.width);// prints the image width


line(mouseX-5,mouseY,mouseX+5,mouseY);
line(mouseX,mouseY-5,mouseX,mouseY+5);
println("x "+mouseX+" :y "+mouseY);
}
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PhiLho 
Re: How could this work?
Reply #1 - May 10th, 2009, 1:40am  
You have to store the position of the rabbit.
On keyPressed(), you update this position, + or - a given offset.
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WWW  
louisa.ivy
Re: How could this work?
Reply #2 - May 10th, 2009, 2:16am  
Could anyone elaborate please? im still a little confused
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blindfish
Re: How could this work?
Reply #3 - May 10th, 2009, 3:56am  
- Define some variables to store the X and Y position of the rabbit (e.g. int rabbitX, rabbitY).
- Do this just below where you declare "PImage c;" and before setup() so they're global.
- In setup() assign the starting values for X and Y - this will be where the rabbit is displayed when the code first runs.
- In draw() adjust the rabbitX and rabbitY appropriately based on keypresses - i.e. something along the lines of rabbitX +=3 when the right arrow is pressed...
- Now instead of hard-coding the x and y into your call to image in the draw() loop:

image(c,300,195,180,380);//Rabbit

pass the values of rabbitX and rabbitY:

image(c,rabbitX,rabbitY,180,380);//Rabbit

Edit: see the sprite example if this still isn't clear.  The only difference in your case is you're using the keyboard to change the 'xpos' and 'ypos'...
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Where is the what if the what is in why?
 
koogy
Re: How could this work?
Reply #4 - May 10th, 2009, 3:57am  
Quote:
How could i get this image- the rabbit to move up, down and to the sides when a key is pressed?

...
image(c,300,195,180,380);//Rabbit
...


the first argument to image is the img to use, the second and third are x and y positions. make these variables and change them on keypresses

image(c, x, y, 180, 380); // rabbit at x,y

then do something like this in your keypress routine
(this is pseudocode, you'll have to look up the correct syntax)
and you'll need to define x and y as ints globally (ie before setup())

if (key == up) then
 y--;
fi

if (key == down) then
 y++;
fi

if (key == right) then
 x++;
fi

if (key == left) then
 x--;
fi
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