touch/drag rapid calls - ios

I'm creating a shooting game where you touch the screen and the player shoots. The problem I have is that when you touch the screen and keep it down dragging it around it shoots rapid fire. What is the best way to deal with this?
I want the player to be able to hold the finger down and shoot at a steady pace, and on finger up stop shooting.
I was thinking of just using a Timer but I don't think that's very efficient... Any other ideas?
Thanks

I would really like to see more details on how you are implementing the shooting, but let me provide you with a way to accomplish this:
In cocos2d, you can use the CCScheduler to schedule a method call, instead of using timers. And this is very efficient. You don't have to worry about performance.
In the scheduled method, you would check whether the user is still touching the screen, and decide to shoot or not accordingly.
Here is some code to get you started:
NOTE: Am using cocos2d v1.0.1 .. in cocos2d v2.0, I think the CCScheduler was moved to the CCDirector.
- (void)init {
// ...
[[CCScheduler sharedScheduler] scheduleSelector:#selector(shoot:) forTarget:self interval:0.2f paused:NO];
// ...
}
- (void)shoot:(ccTime)dt {
if (userIsTouching) {
[player shoot];
}
}

Related

GameplayKit Not Pausing When Scene Is Paused

I have a GKAgent2D governing the movement of an SKNode enemy that moves towards a destination.
When I pause the SKScene that the agent is moving in, the enemy node seems to continue to move without showing such movement. All of the visible movements stop (AKA the enemy stops moving). If I wait 5 seconds then unpause the scene, it's as if the enemy never stopped moving and it pops to where it would have been had I not paused the scene, and it continues to move from that point as normal.
I looked into the sample demo game that Apple had created for users to use called DemoBots and they implement a "fix" similar to what I am using by simply leaving the update:(NSTimeInterval *)currentTime method with a return. Here is what my code currently looks like:
- (void)update:(NSTimeInterval)currentTime {
[super update:currentTime];
if (_lastUpdateTime == 0) _lastUpdateTime = currentTime;
float delta = currentTime - _lastUpdateTime;
_lastUpdateTime = currentTime;
// Stop updating if the `worldNode` is paused.
if (worldNode.paused) { return };
for (GKComponentSystem *componentSystem in componentSystems) {
[componentSystem updateWithDeltaTime:deltaTime];
}
}
But I am unable to dive deeper and find out what else they are doing to ensure that the GKGoal objectives that are currently in effect are stopped right when the pause happens. I even logged the agentDidUpdate method and it stops firing when I pause the scene, so I am really not sure how it continues to move.
If someone knows the answer please let me know. Thank you!
UPDATE: I even tried pausing the individual nodes that have the goals set to move:
- (void)didPauseScene {
worldNode.paused = YES;
/*
<< Animations >>
*/
for (OEnemy *enemy /*my subclass*/ in enemyArray) {
enemy.paused = YES;
}
}
But this still did not stop the GKGoals from continuing as they would without pausing the scene..
UPDATE 2: The ONLY solution that stops the agents cold is literally removing the agent systems purpose:
if (worldNode.paused) {
self.agentSystem = nil;
return;
}
This is a very sad solution as I would hope there is a more elegant / appropriate way of stopping the goals without removing everything completely from the scene. The other issue however is even with this, resetting the goals upon unpausing creates the same issue of the jumping to the position they would be in if no pausing had occurred.
Agents will continue along their last known valid velocity if another goal isn't altering it. If you'd like the agents to stop you could try using GKGoal's goalToReachTargetSpeed:.
For those where the GKGoal goalToReachTargetSpeed: did not work.
Removing my MovementComponent from the entity worked for me:
let movementComponent = entity.component(ofType: MovementComponent.self)!
entity.removeComponent(ofType: MovementComponent.self)
componentSystem.removeComponent(moveComponent)
When you resume your game, make sure you create a new instance of your movement component and add it to the entity again:
let movementComponent = MovementComponent()
entity.addComponent(movementComponent)
componentSystem.addComponent(moveComponent)
When using a GKComponentSystem to update your movement component, also make sure that you remove and add the movement component accordingly.

'Play on' feature is an in-app purchase? SpriteKit/Swift

I'm near the end of developing a game, and long story short, the game will be over when an object crashes into one of the obstacles. I've got that part down and the game runs really well by itself, but there is one more step I am looking to add in.
I would like to add in an in-app purchase of a 'play on' feature, that is, starting where the user's game originally ended so they can continue on. I'm okay with in-app purchases on the whole, but I guess what I want to know is how does one make it possible to 'play on' following the in app purchase? I'm just looking for something basic I can build on.
I'm a Stack newbie, as I've only created an account today (but I've been programming for a little while and this site has helped me so many times), so I'm sorry if there has been a duplicate thread made elsewhere. I did look around for an hour or so before deciding to post (and Google was no help).
As a general stack overflow rule you should always post some of your own code or what code you have played around with.
I am actually also looking to integrate a playOn button in my game. Now I haven't actually found the perfect solution for this yet but hopefully this helps you get on the right track.
Step 1:
How have you programmed your game over scenario?
Are you just pausing the scene, are you pausing nodes or are you removing all children from your scene?
The way I pause my scene is by creating a worldNode and than adding all objects that I need paused to the worldNode.
You can read my two answered questions for more detail
Keeping the game paused after app become active?
Sprite moves two places after being paused and then unpaused
This way when I pause my game I dont actually pause the scene which gives me more flexibility adding pauseMenus etc. Furthermore its seems smoother than pausing the skView.
I also call pause when the player died, which means I could resume the enemies/obstacles from where they left of if I call resume.
So my game over method looks like this
func gameOver() {
pause() // call pause method to pause worldNode etc
//show game over screen including playOn button
}
Step 2:
Now in regards to respawning the player, it depends on how he is positioned, how far he can move etc.
If your player is mostly in the same area than you can probably just respawn you player manually once "PlayOn" is pressed and than resume the game as if it was just paused.
So once your playOn button is pressed you can call a method like so
func playOnPressed() {
// Remove current player
// Doesnt have to be called, you could just change the position
player.removeFromParent()
// Add player manually again to scene or just reposition him
...
// Remove obstacle that killed player
// haven't found a great solution for this yet
// You could make the player not receive damage for 5 seconds to make sure you dont die immediately after playOn is pressed
// Call resume method, maybe with delay if needed
resume()
}
If your player position could be all over the screen, as in my game, I have been playing around with a few things so far.
I created a position property to track the player position
playerPosition = CGPoint!
and than in my scene update method I constantly update this method to the
actual position of the player.
override func update(currentTime: CFTimeInterval) {
if gameOver = false {
playerPosition = player.position
}
}
I than have been playing around with the "playOnPressed" method,
func playOnPressed() {
// Remove current player
//Doesnt have to be called, you could just change the positioon
player.removeFromParent()
// Add player manually again to scene or just reposition him
...
player = SKSpriteNode(...
player.position.x = playerPosition.x - 40 // adjust this so it doesnt spawn where he died but maybe a bit further back
player.position.y = playerPosition.y // adjust if needed
// Remove obstacle that killed player
// haven't found a great solution for this yet
// You could make the player not receive damage for 5 seconds to make sure you dont die immediately after playOn is pressed
// Call resume method, with delay if needed
resume()
}
I hope this helps you playing around with your playOn button, if someone has a better way I would also appreciate it immensely.

is there any way to detect an object is falling or get the speed/direction on axis-y in cocos2d?

I'm a newbie to Cocos2d and game development. Now I'm encountering a problem.
I have a figure and I want to add different animations to it such as jump and fall. For the jump it is fine because I will have a button to trigger jump and I can add animation to it. However, for falling down is another story:
At the beginning, I'm trying to use - (void) update() and it seems this method is for constant moving. Another attempt is try to add a callback for CCAction. However, this can only detect falling after jump.
I'm wondering is there an API to detect an object is falling, or get the speed/direction on axis-Y. Or I have to do it manually and listen frame by frame?
I really appreciate your help =)

How to effectively pause a game in spritekit?

This seems like such a basic concept but there is really no good answer.
I currently have a pretty basic setup, in my game's scene, I have an enum gameState which is currently either inGame or gamePaused.
I have my button set up, and I have it so pressing simply toggles gameState.
Then, to make it work, I have two separate update methods: One for when gamePaused, one for when inGame.
This works for 95% of my game, as the updates in my game can be pretty readily started and stopped without any issues. There are some issues I cannot tackle though.
First and foremost are actions. I use SKActions for a bit of my project (some movement, scaling, fading...) and this method does NOT pause them. This can be catastrophic in certain points. Secondly, this doesn't handle particles, physics, and a few other things that are not directly associated to my update methods.
The only clue I have is self.view.paused = YES, but that isn't going to work either.
First off, this DOES fix my actions, particles, and physics problem... kinda. But This question suggests that SKActions aren't actually PAUSED by this, but actually STOPPED completely. Is this true? If it is, then it won't work smoothly either because my actions are thrown out of whack.
Also, pausing the view seems to do what it says: stop everything. EVERYTHING. Newbie question here, but how am I supposed to get any code to run at that point? It's all cut off. Is this where I need subViews? I have never used a subView yet, but it sounds like its what I want in this case.
Simply put, there are a lot of unanswered questions for me, and I don't know how to proceed. I'm hoping there's some 'standard procedure' for pausing in Sprite Kit, but with pausing the view halting actions I truly have no idea where to proceed.
Should I move away from using actions? Is my idea of a pause subView sound?
I don't want to babble, all I want to know is how you go about pausing in your average Sprite Kit project. Additional info provided upon request.
Pausing a node will pause (not stop) the node's actions, and i suppose pause will also be applied to all children of the paused node in the same way. All other unpaused nodes will continue to run their actions to completion.
You should have a "game layer" node with all game nodes in them that you want to pause, and then just pause that "game layer" node. Then have a "pause game menu" node where you add all the pause menu stuff you need which will continue to function normally even if the game layer is paused.
Be very sure you do not use performSelector or NSTimer or GCD or any other scheduling methods besides actions or the scene's update: method because those will not adhere to a node's paused state.
Pausing the view effectively freezes everything in it, pausing the scene according to some will not pause the update: calls - but I have not verified this myself. If this were the case you can always check inside the update method whether a given node that you send a message to is paused and if so, decide not to send certain messages to that node.
I just called a map function on all children of the scene and set the paused property to true
self.children.map{($0 as SKNode).paused = false}
By setting it to true you can easily undo the freeze.
EDIT:
Better use a for-loop to iterate over the children.
for node in self.children as [SKNode] {
node.paused = false
}
I can tell you what I did in my game:
Pause the SKView on -applicationWillResignActive: (or equivalent, using NSNotifications),
Un-pause the SKView on -applicationDidBecomeActive: (or equivalent, using NSNotifications),
For the actual game scene only, I set a boolean flag _isPaused when resigning active, and if it is true I just skip the -update: method (frame updates). (I also show the "paused" menu when the user resumes the app).
...But my game is a simple puzzle game, and there's no long actions that should continue past the pause/resume. I can not confirm right now that all actions are aborted, but I think it's not the case.
I also used self.children.map{($0 as SKNode).paused = false} and it does work if you create a var layer of type SKSpriteNode and add it on top of the scene. But I also have an NSTimer I'm using to spawn sprites on the scene. Everything currently on the scene is paused, but sprites keep appearing and moving across the screen. It is not pausing the spawning.
I tried pausing the NSTimer when I call the above code by setting repeats to false, then setting it to true when I remove the layer but it doesn't work. I also tried self.scene?.view?.paused = true but that freezes everything and the layer I create does not even appear onscreen.
You need to set the delegate for the View!
func PauseGame(){
self.scene.view.paused = true
}
fun playGame(){
self.scene.pause = false
}
This function is work perfectly if you are not using the NSTimer to call a function. If you use NSTimer your view will pause perfectly but when you play the game again by play game functionality you see that all the functions that use the NSTimer function that runs in the back end and your screen full with your sprite-kits. So when you use NSTimer in the function you have to first pause the NSTimer functions also after that this function work perfectly.
//For Pause
func pauseGame() {
scene?.view?.paused = true
}
//For play.
func playGame() {
scene?.view?.paused = false
}

How do you stop a game after a collision takes place?

I am creating a very simple 2d game where you slide the player across the stage to avoid "rocks" that fall from the top. What I want to happen is for the game to end when my player comes into contact with one of my rocks. This is the code I have right now, I have tried everything so I don't have a clue if I am close to getting it or am way off.
stage.addEventListener(Event.ENTER_FRAME,Collision);
function Collision( e:Event ):void{
if(player.hitTestObject(rock1))
{
gotoAndStop(3);
}
}
when I use this code the player just passes right through the rocks and the frame doesn't change. PLEASE HELP!
Assuming you already have the logic to move the falling rock and to control the player. First you have to put a trace statement to make sure the collision happens, then to end the game just remove the event listener and do whatever is needed like showing a game over screen:
stage.addEventListener(Event.ENTER_FRAME,Collision);
function Collision( e:Event ):void{
if(player.hitTestObject(rock1))
{
trace("player collided with rock1!");
// stop the enter frame event from firing
stage.removeEventListener(Event.ENTER_FRAME, Collision);
// go to game over screen or what ever
gotoAndStop(3);
}
}
Also is better to call the enter frame handler function something better than Collision like onEF, loop...etc

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