I am using starling and tweenMax frameworks in my project.
The trouble I am running into is this:
For the purpose of animating along different paths, I am using tweenmax.
There is one _leaderEnemy that animates along a path and I am pushing several other _shooterEnemy (they are of the same class) into it.
public function createEnemies(enemyNo:int, path:Array, offset:int):void
{
for(var i:uint=1;i<=enemyNo;i++){
if (i==1){
_leaderCount++;
_leaderEnemy = new ShooterEnemy();
_leaderEnemy.x=600;
_leaderEnemy.y=300;
_leaderEnemy.name="_shooterEnemy"+_leaderCount;
this.addChild(_leaderEnemy);
leaderEnemyArray.push(_leaderEnemy);
}
else
{
_leaderCount++;
_shooterEnemy= new ShooterEnemy();
_shooterEnemy.x=0;
_shooterEnemy.y=(offset*(i-1));
_shooterEnemy.name="_shooterEnemy"+_leaderCount;
trace("no: "+_shooterEnemy.name);
leaderEnemyArray.push(_shooterEnemy);
_leaderEnemy.addChild(_shooterEnemy);
}
}
Now I want to check for collision using starling between each of the _leaderEnemy and the _shooterEnemy inside it with _shooterHero.
Running this array successfully checks collision with the whole group i.e. _leaderEnemy but not the individual ones inside it.
Technically, I should be able to do this just by:
var Track:Object;
for(var i:uint=0;i<leaderEnemyArray.length;i++) {
Track=leaderEnemyArray[i];
if (Track.bounds.intersects(_shooterHero.bounds)){
Track.rotation=deg2rad(70);
}
}
It may be something stupid I am doing. But I have not been able to solve this.
Any help on this would be appreciated.
Some other questions I have:
Can I check for collision with _shooterHero from inside the _shooterEnemy's class?
I have tried:
if (this.bounds.intersects(stage.getChildByName("_hero"))){
}
although it did not work.
Can I check for collision of one Enemy with everything on stage, so I can assign individual functions for his each contact?
For example: hit with hero: die; hit with another enemy: turn around
If you need more info, I will be happy to provide it.
Thank You.
Can I check for collision of one Enemy with everything on stage, so I can assign individual functions for his each contact? For example: hit with hero: die; hit with another enemy: turn around
Of course you can. You should! This is approximatively how collision engines works.
Running this array successfully checks collision with the whole group i.e. _leaderEnemy but not the individual ones inside it.
Nope. It won't work. Because the bounds property use the parent coordinates.
Meaning you can intersect each child display (of same container) with each other.
But you shouldn't intersect a child display of A with a child display of B.
Except if you convert every bounds coordinates (which are local) to global.
http://doc.starling-framework.org/core/starling/display/DisplayObject.html#localToGlobal()
Using Track.bounds.intersects is one way of checking collosions. Another would be to use hitTest method of starling.displayDisplayObject
You could also check the distance of your hero and other enemies calculated by a pythagorean theorem type calculation.
Are you checking enemies against each other? If you have many enemies you might want to look into "flocking" algorithms. Keith Petes covers this subject nicely in his book Advanced Actionscript Animation.
Related
I'm developing a cocos2d-x game (version 3.8). My game uses chipmunk physics and it has a static body that works like an interruptor. This interruptor is enabled when another body is over it. The interruptor is disabled when bodies separate each other.
I want to:
Moving body don't collision with interruptor. It has to cross interruptor with no bounce
I want to detect when moving body separates the interruptor
My first approach was implementing onContactBegin method. I return false when those two bodies get in touch. This way the body crosses the interruptor and does not bounce.
The problem is onContactSeparate method is not called, because contact did not happen.
If I return true in onContactBegin method, onContactSeparate is called and I can detect it. The problem is the body does not cross the interruptor, it bounces.
[EDIT] More info
This is the scenario where two sprites are separated. The ball can move and interruptor is a static body. Ball could be over the interruptor.
This is the scenario where two sprites are in contact and object1 (the ball) is over the interruptor. I want to detect where two sprites separate each other.
Any help would be appreciated!
It seems to me like you are using Box2D within cocos, so I'll answer with that as my base assumption.
This is what i would do.
My interrupter would be a b2Body* with no BodyDef dimensions defined or just a 0x0 dimension def.
I would set the user data for the bodyDef to a rectangle that describes my interruption area. This way you can always have your interruption area represented, but will not collide with anything.
(Optional) If you want the interruption area to move around based on the fake body you assigned to it, you can updated it just after the step function using something like below.
world->Step(delta, 10, 10);
for (auto physicsBody = _world->GetBodyList(); physicsBody; physicsBody = physicsBody->GetNext())
{
auto userData = static_cast<Node*>(physicsBody->GetUserData());
if(userData != NULL)
{
// Set interruptor area rectangle = physicsBody->GetPosition();
}
}
To let the rest of the system know when I have left the interrupter I would store a function pointer to the function I want to call when this happens, When a object enters the interruption area I would flag it saying "I'm in the area" after that, the first update step you get when it's not in the area anymore I would fire the callback and reset the flags I used to get to that point.
I hope this helps. You are not giving a lot of context for what you want to do, an image would be helpful. Especially when it comes to looking for help with code that has a visual representation as well.
[EDIT]
Based on the behaviour you want this is the way I did this. The first thing to know is that you don't need physics collisions for the behaviour you want. You can do this by using bounding box intersection tests and use flags and callbacks to figure out the rest.
I have an object that knows about both the ball and my interrupter nodes. In the update loop of this object I check if the two intersects. I set a flag indicating "I am in the interrupter", the next frame that I am not in the interrupter and my flag is still true I call the function that I assigned with my "leaving logic" in it, and set then flag back to false.
I am creating a fighting game. I've got a spritesheet for the hero and a spritesheet for a monster. Since both will be able to do multiple attacks I would like to avoid to merge them in a single spritesheet. And I am intending to create more characters.
Now I am creating a SpriteBatchNode for each spritesheet and add them to layer.
CCLayer* stage = CCLayer::create();
CCSpriteFrameCache::sharedSpriteFrameCache()->addSpriteFramesWithFile("character_hero.plist");
this->characterHeroBatchNode = CCSpriteBatchNode::create("character_hero.pvr.ccz");
CCSpriteFrameCache::sharedSpriteFrameCache()->addSpriteFramesWithFile("character_monster.plist");
this->characterMonsterBatchNode = CCSpriteBatchNode::create("character_monster.pvr.ccz");
stage->addChild(characterHeroBatchNode);
stage->addChild(characterMonsterBatchNode);
Now I have one sprite in characterHeroBatchNode and multiple in characterMonsterBatchNode.
How can I reorder the monsters and the heros z-Order based on their PositionY attribute.
For example>
monster1->setPositionY(10); // In monster batch node
hero->setPositionY(24); // In hero batch node
monster2->setPositionY(43); // In monster batch node
I want the monster 1 behind the hero. And the hero behind monster2.
In the past, I've had to create games where I wanted some sprites in the foreground and others in the background. The sprites were in different sheets, like you have them.
To get them in the order I wanted, I put the "front" sprites into one CCLayer and the "back" sprites into another CCLayer. I added the layers to the scene in the order I wanted them to appear. I also manipulated each the respective layers to make them fade in/out as needed. So you could have the hero in the scene and then have the enemies appear behind him.
If you want to mix and match, you can have 3 layers, one for the "middle ground", one for "front", and one for "back", and dynamically move the sprites between the layers.
Was this what you were looking for?
If I understand what you're asking, the answer is, you can't. Consider each CCSpriteBatchNode to be its own container. You can adjust the Z order of the sprites inside the CCSpriteBatchNode, but when you add the batch to the CCLayer the whole CCSpriteBatchNode is applied to the CCLayer in whatever Z order you added it at. So in order to do what you want you would need another batch of monsters. Or use CCSprites and add/adjust them on the CCLayer in the way you want, but then you obviously lose the CCSpriteBatchNode benefits.
Imagine there is a situation : I have 100 movieclips with instance names : MC1a, MC2a, MC3a .. MC100a
and i want all of them to be invisible is there any other way than :
MC1a.visible = false; ... MC100a.visible = false;
because in this way the code gets very heavy and i thinks it's not the right way. so i was thinking is there any possible way to be something like that :
MC*a.visible = false;
all the movieclips that contains 'MC' in the begging and 'a' and the ending to disappear ? maybe something with array ?
If the parent of all these movieclips is called container you can do :
container["MC"+i+"a"].visible=false
This is due to the script nature of ActionScript.
For your particular case you can do
for(i=0;i<100;i++){
container["MC"+i+"a"].visible=false;
}
If you don't have all number between 0 and 100 you can do something like this :
for each(MovieClip mc in container){
name=mc.name;
if(name.substring(0,2)=="MC" && name.substring(-1)=="a"){
mc.visible=false;
}
}
(This is non tested pseudocode written on the fly)
There are several ways you can achieve this. First - make a Sprite container, which will be their common parent, then alter its visibility. This is not a flexible way, for example, if your movie clips are located on two different areas of stage, and need to interact somehow, you might be unable to put them all under a single parent in your display list. The second way is to make an array out of those 100 movie clips at the time of their instantiation (if possible, of course), then you iterate through the array and assign their visibility in a loop.
Basically, if you have some objects that should form a structure, consider linking them somehow first, then altering their visibility or other parameters all together. Should you need to move them all at once, or hide, the container approach will be better. Should you need them to perform similar, but not exactly same actions (say you have monsters as movie clips, and you need them to move together, but each with their own direction and speed), you should have an array.
Another thing to consider, if there is a movie clip that has a name like "MCbig_a", that is, complies with your condition, but does not exactly belong to the group of MCs you desire to make invisible, you will have to take precautions about such occurrences.
Assuming that al children are added in the same container called myContainer
var container:MovieClip = myContainer;
var i:uint = container.numChildren;
while (i--)
{
var child:* = container.getChildAt(i);
child.visible = false;
}
I am trying to create a way of controlling movieclip depths, which movieclip is show above another, so that I can set the depth of a movieclip to any number and they will be displayed with higher values above lower values.
I was thinking of creating a MovieClipDepth class that extends MovieClip with the added property depth, and a Container class that extends DisplayObjectContainer which all objects will be placed inside of.
The Container class will override the addChild method to update the child display order when a child is added.
What I need help with is how do I reorder the children according to
their depth value?
As you can read in the comment below your question, there are several methods for this.
But actually, what you asked "set the depth of a movieclip to any number" can't really be done in AS3. If i'm correct, you could do this in AS2, so...
... how was it ...
_root.createEmptyMovieClip("mc", -1000);
or
_root.createEmptyMovieClip("mc1", 1);
_root.createEmptyMovieClip("mc2", 10);
worked, but does not work in AS3. In AS3 depth starts with 0 and you can't force a DisplayObject to sit on a level what is not continous from zero.
So the depths' of 3 movieclips in a container is only possible with these values: 0, 1, 2.
Depth can't be a negative number for example.
Now, if you want to build a custom depth manager, you can do that, but you have to consider these facts.
So to say, you could create virtual depths.
So I guess, you could override the addChildAt method for example. At the moment, if you would give a wrong number: negative, or higher then the number of children, flash would give back the error:
RangeError: Error #2006: The supplied index is out of bounds.
So mc.addChildAt(newchild, -1000) gives an arror.
But with overriding the method, you could make a trick, so you could store the depths in an array. You could store any numbers and then transform that order for the needs of AS3.
Like pairing the depths with the added children, sorting the array by the depths, then manage the children according to the order.
If you have more questions, feel free to ask, hope this gets you closer to the solution.
I suggest you take a look at this tutorial :
A Tour of Depths Management Methods on the website http://www.flashandmath.com/. I presume you not a newbie .
The link is this:
http://www.flashandmath.com/intermediate/depths/index.html
I'm building a game of which the interface is one of the first items to load on screen. Sound button, pause and all the bits -
During the game - all manor of things are dynamically added and removed to the stage. Therefore my interface goes behind my game scene.
How do I ensure the movieclip always stays on top?
Can I override the addChild of my Document Class and every time a new child is added, I restack the interface to the top?
You can use setChildIndex to rearrange objects that are already contained within a MovieClip or Sprite. For example, if you have an object called container, which contains a redBall, blueBall and many other ball objects, you can use the following to make sure redBall is behind everything else:
container.setChildIndex(redBall, 0);
Equally you can make sure that blueBall will be displayed infront of everything else using:
container.setChildIndex(blueBall, container.numChildren-1);
addChildAt will sort you out for adding children straight into their correct position, and setChildIndex will allow you to re-position objects already placed. Hope that helps.
debu
Look into addChildAt, it allows you to specify the index that the new object should be added too.
http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/flash/display/DisplayObjectContainer.html#addChildAt%28%29
A good strategy is to keep all interface elements in one parent Sprite/MovieClip, and all game assets in another. (With the interface one on top)
With your guys suggestion I made this, apparently, if you addChild an object already on the screen, it's simply reindex'd to the top. Does this look ok?
private var topLevelChildrenArray:Array = [];
public function addTopLevelChild(child:DisplayObject):DisplayObject
{
topLevelChildrenArray.push(child)
return this.addChildAt( child, this.numChildren - 1 );
}
override public function addChild(child:DisplayObject):DisplayObject
{
this.addChildAt(child, this.numChildren);
for each(var topChild:DisplayObject in topLevelChildrenArray)
{
super.addChild(topChild);
}
return child
}