And!

As I tried to point out in some older posts, beware of parenting, because to scale a parent means to scale all its children, so I am using this to calculate the real size of the object:
public static SimpleVector getSize(Object3D object){
float[] bbox = object.getMesh().getBoundingBox();
Log.i("Util","getSize-bbox:"+Util.floatArrayToString(bbox));
float s = object.getScale();
Log.i("Util","getSize-scale:"+object.getScale());
Object3D[] par;
par = object.getParents();
while(par.length>0){
s = s*par[0].getScale();
Log.i("Util","getSize-parent:"+par[0].getScale());
par = par[0].getParents();
}
SimpleVector out = new SimpleVector((bbox[1]-bbox[0])*s,(bbox[3]-bbox[2])*s,(bbox[5]-bbox[4])*s);
Log.i("Util", "getSize:"+out.toString());
return out;
}
Enjoy,
Darai.

Hi guys,

Imagine, you have some 50+ objects in JPCT world. You have the renderer, taking care for the onDrawFrame() method and some onTouchEvent() method switching on and off the switches according the user demands.

Now, every turn each object does something - let's say it moves by predefined vector. This is a very simple type of physics, where the objects have no interaction, but they have some behavior.

Up until now, when i wanted to do something like that, I used a temporary solution. A for cycle in the onDrawFrame() method to cycle through each object.

I expect that there is a better solution, like threadding or using Android Services or there is some onDraw listener for the Object3D simillar to onCollision listener or if I have to implement a real physics, like Bullet even for a simple example like this one... but I don't know which is the best one to use.

To demonstrate it in example:
Lets say I have this:

public ExtendedObject[] objects;

public class ExtendedObject{
public Object3D theObject;
public SimpleVector speed;
public void move(){
// Do something
this.theObject.translate(this.speed);
}
}

// And somewhere in the Renderer with FrameBuffer fb
public void onDrawFrame(GL10 gl) {
for(int i =0;i<objects.length;i++){objects[i].move();}
fb.clear(back);
world.renderScene(fb);
world.draw(fb);
fb.display();
try {
Thread.sleep(20);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
Thanks for every hint.
Darai.

Hi guys,

i found this strange behaviour in cloneObject:
Object3D first = Primitives.getBox(1f, 1f);
first.setScale(2f);
Object3D second = first.cloneObject();

Now, first has scale == 2, second has scale == 1, their Object3D.getMesh().getBoundingBox() returns the same set of numbers, but the displayed object second has the same size as the scaled object first.

Is there problem somewhere on my side, or do you see the same behaviour?

Hmm...

To be blunt, I don't feel like the big expert for this... sure, I am a little bit programmer and little bit mathematician, but with BIG but. That is why I hoped that I will post it to a thread and after some corrections from the proper programmers or math gurus it could be transformed into a proprer wiki page. But if you prefer me to write a prototype of such a wiki page and let the people to do the corrections directly there, I am with you so go for it.

Darai.

All right,

now I expect that I have an old version, even though I downloaded it 2 days ago from the page
http://www.jpct.net/jpct-ae/

I did the config thing you recommended, it says that I have version 1.28... Where can I find which is the most current version? Ok, I found here in forum your link with the version 14/07/30... but can I (next time) verify the version somewhere without downloading the file and comparing size/date/Config.version?

07-30 03:19:48.641: I/onDraw(1487): >>>>>>>
07-30 03:19:48.641: I/safeLoad(1487): loading:tex
07-30 03:19:48.641: I/safeUnload(1487): unloading:tex
07-30 03:19:48.641: I/safeUnload(1487): previousID:1
07-30 03:19:48.651: I/safeUnload(1487): newID:1
07-30 03:19:48.651: I/jPCT-AE(1487): Loading Texture...
07-30 03:19:48.651: I/jPCT-AE(1487): Texture loaded...16384 bytes/64*64 pixels!
07-30 03:19:48.651: I/safeLoad(1487): newID:1
07-30 03:19:48.651: I/safeLoad(1487): names:tex
07-30 03:19:48.651: I/safeLoad(1487): names:--dummy--
07-30 03:19:48.651: I/onDraw(1487): JPCTVersion: 1.28
Thanks,
Darai.

Hmm...

Ok, I downloaded the newest JPCT-AE... i had the version 14/05... but it didn't helped.. I am running this command in the onDrawFrame() thread in the renderer, is that correct?

Another thing that could cause this is that I see the problem on the emulator, I can and will werify today if the same problem is also on the real Android device.

Thanks,
Darai

Hi guys, i have problem with TextureManager,

I am lazy to remember which texture names I used and which I didn't, so I created a "safeLoad" which looks if such name exists and if yes, it unloads it. I am using the getTextureID method to find out if the texture exists or not, but i found out that following code can end in infinite loop... do you know why and what do I have to do differently to find out if the texture is still there or not?

while(TextureManager.getInstance().getTextureID(name)!=TextureManager.TEXTURE_NOTFOUND){
TextureManager.getInstance().removeAndUnload(name, AstroRenderer.getFrameBuffer());
};


Thanks,
Darai

Hi guys,

I am fighting with scale for some time, so I created a simple example and was surprised bz the result. The Object3D was a triangle, created by addTriangle method, I created a clone of the same object and scaled it, expecting the 0,0,0 point to be still on the same spot. Surprise surprise this didnot happend and I am trying to understand why and what I have to do to get the result I expected.

Source code:
Object3D o1 = new Object3D(1);
o1.addTriangle(   new SimpleVector(-10f,-10f,0), 0, 0,
            new SimpleVector(-10f,10f,0), 0, 1,
            new SimpleVector(0f,0f,0), 1, 1,
            texID);
o1.setScale(1);
world.addObject(o1);

Object3D o2 = new Object3D(o1);
o2.setScale(2);
world.addObject(o2);
The result is in attachment. Short to say, the triangles are scaled from theirs centers, not from the 0,0,0 point.

Thanks,
Darai


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