Hi,
I found this great code from Daniel Shiffman to load 10 images, that are stored in an array. I would like to diplay the images on specified positions. Each image has an index-nr. in the array, that should correspond to a specified postion. Does anybody did tra this?

thanks!

frank

-------------

int imgCount = 10;
PImage[] imgs = new PImage[imgCount];
float imgW;

// Keeps track of loaded images (true or false)
boolean[] loadStates = new boolean[imgCount];

// For loading animation
float loaderX, loaderY, theta;

void setup() {
 size(800, 400);
 smooth();
 imgW = width/imgCount;

 // Load images asynchronously
 for (int i = 0; i < imgCount; i++){
   imgs[i] = requestImage("dublin"+i+".jpg");
 }
}

void draw(){
 background(0);
 
 // Start loading animation
 runLoaderAni();
 
 for (int i = 0; i < imgs.length; i++){
   // Check if individual images are fully loaded
   if ((imgs[i].width != 0) && (imgs[i].width != -1)){
     // As images are loaded set true in boolean array
     loadStates[i] = true;
   }
 }
 // When all images are loaded draw them to the screen
 if (checkLoadStates()){
   drawImages();
 }
}

void drawImages(){
 for (int i = 0; i < imgs.length; i++){
   image(imgs[i], width/10*i, 0, imgW, height/10);
   //image(imgs[i], width/10*i, 0, imgW, height);
 }
}

// Loading animation
void runLoaderAni(){
 // Only run when images are loading
 if (!checkLoadStates()){
   ellipse(loaderX, loaderY, 10, 10);
   loaderX += 2;
   loaderY = height/2 + sin(theta) * (height/2.5);
   theta += PI/22;
   // Reposition ellipse if it goes off the screen
   if (loaderX > width + 5){
     loaderX = -5;
   }
 }
}

// Return true when all images are loaded - no false values left in array
boolean checkLoadStates(){
 for (int i = 0; i < imgs.length; i++){
   if (loadStates[i] == false){
     return false;
   }
 }
 return true;
}

you can easily use a 2d array to store the x and y coordinate of every image/index

http://processing.org/learning/tutorials/2darray/

if this tutorial doesnt make it clear, ill come back to you. But give it a try

So why is it?
Maybe an explaination would be useful here.

ah k, i remember his threat. i understand his point but dont have a big problem with using a 2d array to store 10 coordinates. I started to do it that way before pvector was introduced. So thats a bad habit im still used to.  but its true and Philho is right, its probably easier for beginners so you should use a pvector instead although you probably wont use all the calculations you can do when using them.

Dear PhiLho,
I tried to implement the Vector solution, but always get thuis error:

---------------------------------------------------
Exception in thread "Animation Thread" java.lang.NullPointerException
     at _1_array_images2exp2.drawImages(_1_array_images2exp2.java:59)
     at _1_array_images2exp2.draw(_1_array_images2exp2.java:50)
     at processing.core.PApplet.handleDraw(PApplet.java:1425)
     at processing.core.PApplet.run(PApplet.java:1327)
     at java.lang.Thread.run(Thread.java:619)

---------------------------------------------------
Here the code:

int imgCount = 10;
PImage[] imgs = new PImage[imgCount];
float imgW;
PVector[] imgPos = new PVector[imgCount];
// Keeps track of loaded images (true or false)
boolean[] loadStates = new boolean[imgCount];
// For loading animation
float loaderX, loaderY, theta;


void setup() {
 size(800, 600);
 smooth();
 frameRate(1);
 imgPos[0] = new PVector(20, 10); // first image location
 imgW = width/imgCount;  
  // Load images asynchronously
 for (int i = 0; i < imgCount; i++){
   imgs[i] = requestImage("dublin"+i+".jpg");
 }
}

void draw(){
 background(#FFFFFF);
 for (int i = 0; i < imgs.length; i++){
   // Check if individual images are fully loaded
   if ((imgs[i].width != 0) && (imgs[i].width != -1)){
     // As images are loaded set true in boolean array
     loadStates[i] = true;
   }
 }
 // When all images are loaded draw them to the screen
 if (checkLoadStates()){
   drawImages();
 
 }
}
void drawImages(){
for (int i = 0; i < imgs.length; i++){
   // width and height taken from the image
     image(imgs[i], imgPos[i].x, imgPos[i].y);
}
}
// Return true when all images are loaded - no false values left in array
boolean checkLoadStates(){
 for (int i = 0; i < imgs.length; i++){
   if (loadStates[i] == false){
     return false;
   }
 }
 return true;
}




THANKS one more time.-

fr

inst wrote on Dec 14^th, 2009, 2:53am:

..which of course means you need to specify the positions!

Code:

  imgPos[0] = new PVector(???, ???); // 1st image location
  imgPos[1] = new PVector(???, ???); // 2nd image location
  imgPos[2] = new PVector(???, ???); // 3rd image location
  imgPos[3] = new PVector(???, ???); // 4th image location
  // ...
  imgPos[9] = new PVector(???, ???); // 10th image location 

where hopefully it is obvious that you need to fill in the '???' parts with the co-ordinates you want!

-spxl

You need to go and do some reading / tutorials on how to program.

Having people answer every step of your problem is not going to help you.

See the Learning link in the navigation at the top of this page.

-spxl

You can ask, but I suggest you could do better.

My recommendation is that you do (or at least read through) some tutorials, where you will learn basic ideas like how to move an object over time.

It is obvious you haven't done this, and the tutorials are there to teach you, which makes more sense than having people answer questions about basic concepts over and over.

The answer you seek is in the tutorials.

Read the tutorials.

-spxl

PS: The new drawImages() method you posted appears terribly confused. You evidently are reaching out to do something, but without some background knowledge (such as gained from the tutorials) you will remain hopelessly lost.