I am trying to create a timer to limit the amount of time a player can use their jetpack in my phaser game. I've been following this(http://www.joshmorony.com/how-to-create-an-accurate-timer-for-phaser-games/) but I can't get anything to work. Is there a better way to implement this?
var use_jetpack;
jetpack_timer = game.time.events.add(
Phaser.Timer.SECOND * 1 /*change the 1 to however many seconds you want*/,
end_jetpack /*runs the function end_jetpack*/,
this);
function end_jetpack(){
use_jetpack = false;
//if you want a cool down, put it here. follow what was done in line 3.
}
if(use_jetpack){
//player can use jetpack
}else{
//player cannot use jetpack
}
Try this. I don't know what you couldn't get to work, but this is what my implementation would be. Of course you would need to put functions in update(), and the variable wherever you put those. This is just a quick demo. Also I had odd formatting for teaching purposes.
Related
I'm using p5js to program an animation with a timer countdown. I set my timer up to be updated each frame within an object that is being animated by the draw() function in sketch. Because of this, setInterval() will not work for what I'm trying to do.
I thought I could use the frameRate and a frame counter to decide if a second has passed:
this.updateTimer = function(){
this.framecounter++;
if(this.framecounter > frameRate()){
this.framecounter = 0;
//increment seconds
}
}
Is this reliable? I tested it against an actual timer and it seems to be about 1 second ahead after about 15 seconds. Is there a better way to do this by calling a function each frame? Thanks!
Why don't you just use the frameCount variable? More info is available in the reference.
You could also use the millis() function instead. Again, the reference is your best friend.
If you still can't get it working, please post a MCVE (or better yet, a CodePen or JSFiddle) that we can run to see the problem.
I have four objects I want to appear, one after another, with one second in between. What's the standard way of doing time-based animation?
My idea is to to continually ask for the Ticker's time for a period of 5 seconds, and when the Ticker hits the 1-, 2-second marks, the objects get created:
startAnimationTime = Ticker.getTime();
while (Ticker.getTime()-startTime < 5000) {
if (Ticker.getTime() == 1000) {
// create first object
} else if (Ticker.getTime() == 2000) {
// create second object
} else if ...
Is there a more elegant way of doing this? Thanks!
You could use TweenJS for this. Other than animation, it makes a swell timer, mainly due to the chaining you can do with it.
var tween = createjs.Tween.get(this).wait(1);
for (var i=0; i<10; i++) {
tween.wait(2000).call(createObjectFunction, [i, otherArg], this);
}
tween.call(doneFunction, null, this); // Call something when done
This will run a function every 2 seconds, 10 times.
I would suggest using TweenMax/GSAP an awesome tweening engine with a timeline engine as well. You could do what you want in various ways. Simplest would be:
TweenMax.delayedCall(1, function(){//create first object });
TweenMax.delayedCall(2, function(){//create second object });
etc...
...or use TimelineMax or TimelineLite to properly control things.
Just realised it's basically exactly what #Lanny said but using a different tweening engine. The advantage of Lannys suggestion is tweenJS is already there in createJS, I just use TweenMax/GSAP because I'm used to it ;)
So my problem is I want to insert a custom animation but I don't want to ruin my gameloop.
My initial gameloop is stated here:
function init(){
if(!gameOver){
if(resetInterval>-1) clearInterval(resetInterval);
createBlock();
resetInterval = setInterval(moveDownCheck,gameSpeed);
}
}
My game is a tetris like game except instead of dropping tetriminos, I drop 2x1 blocks of different color. The moveDownCheck method checks if there are any blocks under my 2x1 block and then drops it by 1 row. This works fine until I have a block hanging without a block underneath since the 2x1 blocks are connected. I want to insert a drop animation that would take about a second and drop the hanging block by the same gameSpeed increment.
Here is my attempt that doesn't work:
function moveFallingDown(){
fbDownFlag = false;
clearInterval(resetInterval);
fbInterval = setInterval(function(){
fallingBlock.row++;
console.log("Dropped One Row");
},gameSpeed);
while(landscape[fallingBlock.row+1][fallingBlock.col]==0){
console.log("Waiting to Drop Falling Block");
}
clearInterval(fbInterval);
resetInterval = setInterval(moveDownCheck,gameSpeed);
}
Here I am attempting to wait for the function(){fallingBlock.row++;}, but my game just crashes and in the console "Dropped One Row" yet "Waiting to Drop Falling Block" will display thousands of times.
I guess I shouldn't be using a while loop here, but the only other solution I can think of would be a complete rework of my design, or nested setInterval methods which would just make my head hurt too much.
You can't do this with a while loop, you need to use a recursive function. window.setTimeout would work, however this seems like a good use case for requestAnimationFrame. Check it out here: https://developer.mozilla.org/en-US/docs/Web/API/window.requestAnimationFrame
You can use that to call your moveFallingDown method, and check how long has passed since the last animation frame to move your animation the right amount according to the game speed, by using the high precision timestamp passed to the requestAnimationFrame callback.
#Adrien Delessert's advice is correct but I'll just add that you're definitely confusing setTimeout and setInterval.
First of all you don't need a while loop.
setInterval IS a loop. So, if you wanted to use it you'd need to wrap (basically) the whole game in a method that moves the game forward (whatever that means) and pass that to setInterval.
However, what you're doing (and this is actually not a terrible approach) is to use it as a means to animate specific things. In that case you should have a recursive(ish) function that keeps calling setTimeout when it's done, if the conditions for another round of animation are met.
I haven't ever used requestAnimationFrame, but that does sound like a much more elegant approach to the problem.
The reason it's better is that it leverages the browser's own refresh timer (about 60 times per second) and will slot your animation frames in along with its own refresh.
So yes, you will listen for that callback and then react to it as necessary. If 60x per second is too fast, you'll need to put in a % based counter for how many of those frames you wish to actually react to.
A while ago I created a small cardgame web app for fun. The player plays against the computer and mostly it works fine. Sometimes though the computer player gets into a loop, the point of the game is to lose all your cards and if you don't have a card to play you take the pile. Sometimes the computer plays x,y,z, takes the pile, plays x,yz, takes the pile etc.
I keep track of the moves I've made, so at any point I have an array that looks something like : [C2,D5,H2,S4,C5,H2,S4,C5,H2,S4,C5]
In this case I can see that I've gotten into a loop of playing H2,S4,C5, then taking the pile and then repeating.
So, the generalized problem is, what's the best way to detect repeating patterns in a list? I could probably whip something up using a simple for loop, trying to find the card I'm about to play and if I find that in position x then I could check whether the pattern from x to n repeats at position x-(n-x) to x, but this seems like the kind of problem that could have a nice algorithm for it. How would you code this given the following function signature:
function findLoops(previousMoves, nextMove, maxPatternLength) {
//Return [loopLength, loopCount] or null if there are no loops
}
p.s. this is not a homework assignment, the game exists and is at http://www.idiot-cardgame.com if anyone is interested :)
First the general question: Your suggested method
trying to find the card I'm about to play and if I find that in position x then I could check whether the pattern from x to n repeats at position x-(n-x) to x,
looks really good. I would suggest basically the same. It is O(n) and needs a fixed amount of storage, and is simple: what else would you wish for?
Second: You can check for repetition in games generally if you keep a hash table of all previous game states (complete state, nothing left out). Everytime you reach a new state look up if it is in the hashtable, if its in it: you game state is looping.
In Javascript you have builtin hastables so this is very easy to do with something similar like this:
new_state = next_move(old_state);
new_encoded_state = encode(new_state); // make it into a string
if (allstates[new_encoded_state]) {
// we are looping!
} else {
allstates[new_encoded_state] = 1;
// no looping
}
The variable allstates is not an Array but of type Object. You can have array like access with strings and this uses the Object as hastable.
I have from the backend a time on the format 00:12:54 and I display it to the screen. But, I would like to have this time to continue to go down. I have though to create a variable in javascript that will old the time and with setTimeout to loop to display with document.getElementById the new value. I think it can be problematic if I have many time to go down in same time. I might require an array?
How would you do that? If I have no other suggestion, I will try my way, but I am curious to know if it does have a more secure way to do it.
Do you know jQuery Framework? It's a Javascript framework that have a lot of utilities methods and functions that let you do Javascript stuff more easily.
Here is a count down plugin (haven't tested it).
I suggest you to download JQuery than download the plugin . Check the sample of code from the "relative" tab on the website. You can have something like :
$('#until2d4h').countdown({until: '+12M +54S'});
*The only drawback with what I suggest you is that you will require 2 .js to be added. Try to add them only when needed and you will be find.
General algorithm:
Read time from server.
Read the current time.
Call a function.
In your function, read the current time, get the delta from the initial time you read in step 2.
Subtract the delta from the initial time you read from the server in step 1 and display the remainder.
The function should call window.setTimeout to call itself in 1000ms (or adjust according to time elapsed within the function), if you want to continue counting down.
Here's a rough cut:
window.onload = function () {
var countdown_start_in_ms = 6000; // from server
function tick() {
var now = new Date().getTime();
var disp = start - now;
if (disp < 0) {
disp = 0;
}
var el = document.getElementById("countdown");
el.innerHTML =
// quick hack to format time
/(\d\d:\d\d:\d\d) ...$/.exec(new Date(disp).toUTCString())[1];
if (disp > 1000) {
var elapsed = new Date().getTime() - now;
window.setTimeout(tick, 1000 - elapsed);
} else {
// stop countdown and set color to light grey
el.style.color = "#ccc";
}
}
var start = new Date().getTime() + countdown_start_in_ms;
tick();
}
You won't like the taste of this one, but it'll do you good:
Google for 'javascript timer' and get your hands dirty reading through the various examples and tutorials returned by that search.
You'll learn a lot more than just how to write a count-down timer. :-)
Good luck!
Take a look at Grab hands and set your own time. and inspect its code. While it is written with Dojo, the "clock" part is in plain JavaScript. In your case the only difference is how to advance the counter — decrease rather than increase it.