I'm using Phaser 2.4.2 with P2 physics. I have a sort of jar shaped body containing some circular bodies (balls). I want to move the jar offscreen but the balls are colliding with the world bounds.
I tried setting collideWorldBounds on the balls like so:
ball.body.setCircle(64);
ball.body.collideWorldBounds = false;
but this stops them colliding with the jar which I want -- the result is gravity makes them drop offscreen.
You can see a demo here: https://output.jsbin.com/vuyexo
Click the red button to make the jar move.
Uncomment collideWorldBounds=false in the 'balls' section.
Why is this happening and how can I make the balls collide with the jar body but not the world bounds when the jar is moved offscreen?
You can set the P2 world bounds using setBoundsToWorld so like this
//..
game.physics.p2.gravity.y = 300;
game.physics.p2.setBoundsToWorld(false, false, true, true); // left=false, right=false, top=true, bottom=true
Alternatively you could just make the P2 world larger, so for example make the width 2000 instead of 768.
game.world.setBounds(0, 0, 2000, 1024);
By default p2 collides everything with everything else, but if you want it to do something different then you have to explicitly list which objects collide with each other by adding each body to a collision group and then calling body.collides like this:
var jarCG = this.physics.p2.createCollisionGroup();
var ballsCG = this.physics.p2.createCollisionGroup();
jar.body.setCollisionGroup(jarCG);
jar.body.collides(ballsCG);
for (var i = 0; i < 9; i++)
{
var ball = balls.create(250+(i%3)*128,300+Math.floor(i/3)*128);
ball.body.setCircle(64);
ball.body.debug = true;
ball.body.collideWorldBounds = false;
ball.body.setCollisionGroup(ballsCG);
ball.body.collides([jarCG, ballsCG]);
}
This is working for me, but using a tween to move the jar still makes the physics act weird. You can fix it by either using jar.body.velocity.x instead of tweening or by also tweening all the balls. You can also try tweening stack.x if you just want to move the sprites, but for some reason this isn't moving their bodies.
Related
I'm trying to use an animation for a sudoku app. I want for everytime i insert a wrong number, that number would change color and it's scale.
My code is:
override fun onDraw(canvas: Canvas?) {
canvas ?: return
drawBoard(canvas)
drawNumberProblem(canvas)
}
private fun drawNumberProblem(canvas: Canvas){
paint.color=darkcolor
paint.textSize = cellSide*3/4
SudokuGame.numbersproblem.forEach { e->
canvas.drawText("${e.number}", originX + e.col * cellSide+cellSide/5, originX + (e.row+1) * cellSide-cellSide/10, paint)
}
}
And i tried:
private fun initAnimation() {
var animation = RotateAnimation(0f, 360f, 150f, 150f)
animation.setRepeatCount(Animation.INFINITE)
animation.setRepeatMode(Animation.RESTART)
animation.setDuration(7500L)
animation.interpolator = LinearInterpolator()
startAnimation(animation)
}
override fun onDraw(canvas: Canvas?) {
canvas ?: return
if(animation==null)
initAnimation()
drawBoard(canvas)
drawNumberProblem(canvas)
}
private fun drawNumberProblem(canvas: Canvas){
paint.color=darkcolor
paint.textSize = cellSide*3/4
SudokuGame.numbersproblem.forEach { e->
canvas.drawText("${e.number}", originX + e.col * cellSide+cellSide/5, originX + (e.row+1) * cellSide-cellSide/10, paint)
}
}
The animation, the board and the numbers are all good. The animation is only an example, i tried to rotate it to see if it's working. But the only problem is that the animation is working for the whole board, i want to have animation only over numbers.
Is there any way to create a initAnimation with a parameter like initAnimation(drawNumberProblem())?
I am new to kotlin animation, so i don't really care about the best way to do it, i want to find a simple way to understand it.
Thanks
If each cell is its own View (say a TextView) you can animate it the way you're trying to, and the animation framework will take care of the timing, the rotation and scaling, etc. Because each view is separate, they can all be animated independently, using Android's view animation libraries, and a lot of the work is taken care of for you - it's pretty easy to use!
If it's all one view, and you're drawing a bunch of elements which can all be animated, you have to keep track of those elements, any animations that should be happening to each one, and how each animation's state affects the element when it comes time to draw it. Instead of each view having its own state and being drawn separately, you have to draw the whole thing at once, because it's a single view. So you need to keep track of those individual element states yourself, so you can refer to them when drawing the current overall state.
So for example, say you've got an animation where an element needs to scale to 2x the size and then back to normal, and it runs for 1 second total (1000ms). When you come to draw that element, you need to know how far along that animation you are at that moment, so you can scale it appropriately, and draw it at the correct size.
There are lots of ways to do this, probably some smarter ones, but this is the most basic hands-on example I think. I'm not testing this, but hopefully it gives you the idea:
// for brevity, so we can just say "now" instead of writing out the whole function call
val now: Long get() = System.currentTimeMillis()
// store a start time for each grid cell (or null if there's no anim running)
val animStartTimes = Array(CELL_COUNT)<Long?>
val animLength = 1000 // millis
// Basic function to start an animation - you could adapt this to prevent restarts
// while an anim is already running, etc
fun startAnim(cellIndex: Int) {
animStartTimes[cellIndex] = now
// tell the view it needs to redraw (since we're animating something now)
invalidate()
}
// Get the current progress of an animation in a cell, from 0% to 100% (0.0 to 1.0)
// I'm treating a finished item as "reset" to its original state
fun getAnimProgress(cellIndex: Int): Float {
val start = animStartTimes[cellIndex]
if (start == null) return 0f
val progress = (now - start) / animLength
if (progress > 1f) {
// animation has ended (past 100% of its runtime) so let's clear it
animStartTimes[cellIndex] = null
return 0f // like I said, I'm treating finished animations as "reset" to 0%
} else return progress
}
override fun onDraw(canvas: Canvas) {
// this flag can be set to true if we find an element that's still animating,
// so we can decide whether to call invalidate() again (forcing a redraw next frame)
var animating = false
items.forEachIndexed { i, item ->
val animProgress = getAnimProgress(i)
if (animProgress > 0f) animating = true // set that flag
// now you need to use that 0.0-1.0 value to calculate your animation state,
// e.g. adjusting the text size by some factor - 0.0 should produce your "default" state
}
// finally, force a redraw next frame if necessary - only do this when your view
// contents might need to change, otherwise you're wasting resources
if (animating) invalidate()
}
I hope that makes sense - obviously I haven't shown how to actually draw the states of your animation, that depends on exactly what you're doing - but that's the basics of it. It's a lot more work than using view animation, but it's not too bad when you get the idea.
The drawing part is a little more complex, and you'll probably want to get familiar with manipulating the Canvas - e.g. to draw a rotated character, you turn the canvas, draw the character as normal, then undo the canvas rotation so it's the right way up again, and the character is tilted. I don't have time to look for any tutorials about it, but this article covers the matrix operations that scale/rotate/etc the canvas
So yeah, it's a bit involved - and depending on what you want to do, a grid of TextViews might be a better shout
On this link there is an example of a game developed using Phaser
http://examples.phaser.io.
Your tank is a sprite with a turret sprite anchored on it:
// The base of our tank
tank = game.add.sprite(0, 0, 'tank', 'tank1');
tank.anchor.setTo(0.5, 0.5);
...
// Finally the turret that we place on-top of the tank body
turret = game.add.sprite(0, 0, 'tank', 'turret');
turret.anchor.setTo(0.3, 0.5);
..
Also notice the following in the update function that executes every frame:
turret.x = tank.x;
turret.y = tank.y;
Notice that when you accelerate, the turret lags a bit and catches up with the underlying tank sprite only when you reach zero velocity. How to fix this?
a little bit late.. you should consider that your sprite uses physics that renders in various sections. Try to see API DOCs preUpdate, postUpdate, Phaser.World.
So, in your case, if you use for instance ARCADE Physics, you should reload data of your x,y via body which belongs to arcade.physics, not other.
tank = game.add.sprite(0, 0, 'tank', 'tank1');
tank.anchor.setTo(0.5, 0.5);
game.physics.enable(tank, Phaser.Physics.ARCADE);
......
turret.x = tank.body.x;
turret.y = tank.body.y;
Iv looked around online for a solution to this issue but iv been unable to solve it.
I want to extend the sprite class to make my own interactive circle. Everything works but setting the X,Y, Width and height of the custom class does not work:
class CircleDraw extends Sprite
{
public function new(x:Int,y:Int,width:Int,height:Int)
{
super();
this.x = x;
this.y = y;
this.width = width;
this.height = height;
drawCircle();
}
private function drawCircle()
{
this.graphics.beginFill(0xffffff);
this.graphics.drawCircle(this.x,this.y, this.width);
this.graphics.endFill();
}
}
The approach above does not work as expected, setting x,y and width via the constructor results in literally nothing appearing. Yet if i set them manually, either within the class
this.graphics.drawCircle(200,200, 30);
Or prior to addChild:
circle = new CircleDraw(10,10,100,200);
circle.x=100;
circle.y=100;
it then appears on screen. also after adding it like so once the values have been added manually within the class rather than this.x etc:
circle = new CircleDraw(10,10,100,200);
addChild(circle);
So my question is this, how do i extend a class (Sprite) and allow the constructor to modify its parents default variables and keep the values?
EDIT
Just to provide all the code as requested:
This does not work:
circle = new CircleDraw(10,10,100,200);
addChild(circle);
when Circle draw is like this:
class CircleDraw extends Sprite
{
public function new(x:Int,y:Int,width:Int,height:Int)
{
super();
this.x = x;
this.y = y;
this.width = width;
this.height = height;
drawCircle();
}
private function drawCircle()
{
this.graphics.beginFill(0xffffff);
this.graphics.drawCircle(this.x, this.y, this.width);
this.graphics.endFill();
}
}
It does work if i modify the method:
private function drawCircle()
{
this.graphics.beginFill(0xffffff);
this.graphics.drawCircle(200, 200, 30);
this.graphics.endFill();
}
Or if during the instancing of the object i set the X and Y variables as mentioned before the edit.
You are indeed setting the base class variables successfully, it's just that DisplayObject.width has a rather specific (and perhaps not that obvious) behavior.
width:Float
Indicates the width of the display object, in pixels. The width is calculated based on the bounds of the content of the display object. When you set the width property, the scaleX property is adjusted accordingly, as shown in the following code:
Except for TextField and Video objects, a display object with no content(such as an empty sprite) has a width of 0, even if you try to set width to a different value.
—OpenFL API: DisplayObject: width
In this sense, OpenFL follows the ActionScript 3.0 API.
From what I can surmise, it looks like you're trying to override a constructor (new) that takes no arguments.
I'm not entirely sure, but that might not get you what you want. What I think you're actually doing is just creating a method "new" on the extended class, and then within it, feeding the parent nothing (super()). So the parent will not have the constructor arguments. It would be interesting to do look at that object in a debugger and look at the instance properties vs. the parent ones.
There's probably a way around that, but I think you might want to look at doing this via composition instead of inheritance. For example, in "new", create a new instance of a sprite, and manipulate the properties of that.
class MySprite
{
public var sprite : Sprite;
public function new ( ) {
sprite = new Sprite ();
}
}
You would then perform your operations on that sprite instance. Essentially, you are just wrapping a sprite in your own class. Decorator, more or less.
I found some reference to the topic here (it's been a while since I did any Flash programming), it shows addChild and removeChild implementations, etc.
http://old.haxe.org/forum/thread/685
From the (partial) code you posted, it looks it should work.
In other words, setting parent's variables like that should work.
I doubt there are some other code you didn't post gets in the way. I suggest you print out the x, y values in the drawCircle call to debug.
I also doubt the circle is drawn off-screen so you can't see it. Because you first moved the sprite, to (x,y) and then draw a circle in (x,y) inside the sprite. So effectively the circle is at (2x,2y) in global space
EDIT:
this.graphics.drawCircle(200,200, 30);
You claim this worked. Should draw at (210,210) with radius 30
circle = new CircleDraw(10,10,100,200);
circle.x=100;
circle.y=100;
You claim this worked. Should draw at (200,200) with radius 100
circle = new CircleDraw(10,10,100,200);
addChild(circle);
You claim this didn't work. Should draw at (20,20) with radius 100
From the above three version, you are actually drawing at different places with different sizes. So I still suspect that "didn't work" may due to the fact that you are drawing at some places not in sight.
So I still suggest you print out the value of x, y, width inside the private drawCircle function to see what's happening
Be aware, that you are kind of dealing with 2 coordinate spaces. The one were the Sprite will be added and the graphics object of that Sprite. If you set this.x and this.width you are actually setting properties of this Sprite. So in regards of positing you are moving the Sprite itself in that case. The Sprite "graphics" property has it's own coordinate space.
For example if you pass x=100 in your CircleDraw constructor function you are first moving the sprite itself by x=100 and then draw the circle with an x offset of 100. So if you would add the sprite directly to the Stage you would start drawing your circle actually at x=200, because you effectively applied the position twice. It seems to me this is not what you actually are intending.
Also your CircleDraw instance (which is also a Sprite of course) is "empty" when you are constructing it. So calling this.width = width in your constructor has no effect. this.width will stay 0 because the Sprite has no contents at that point. So in the drawCircle method you are drawing a circle with a width of 0.
Probably the better solution would be to simply pass the arguments of your constructor function to your drawCircle function, without setting any properties.
I made a galaxy sketch in p5.js using rotates and radians, but it's erased each time the background() is loaded as draw() runs. Is there a way to over-ride the background() function? I want the galaxies to remain in view.
var stars;
function preload(){
//for (var i = 0; i < planetArray.length; i++) {
//stars = loadImage('Assets/stars.png');
}
function setup(){
createCanvas(windowWidth, windowHeight);
}
function draw() {
//background(0);
star()
//function mousepressed(){
}
function star(){
//angle = map(mouseX, 0,width, 0,360);
//rotate(radians(angle*100));
noStroke();
//translate(width/2, height/2);
translate(mouseX,mouseY);
fill(0);
rotate(radians(frameCount%360)); //rotates output of ellipses
rotate(radians(1000*frameCount%360));
for(var i =0; i < 20; i++){
push();
noStroke();
fill(random(200),0,random(150),random(2));
// fill(random(125),random(250),random(100));
ellipse(10*frameCount % (width/10),0,10,10);
//image(stars, 10*frameCount % (width/2),0,10,10)
//image((10*frameCount % (width/2),0,10,10)
//
pop();
}
}
Well, there really isn't any magic to it. Calling the background() function fills the window with a solid color (or image) and draws over anything you've previously drawn.
The solution to this problem isn't to "over-ride" the background() function. It's to restructure your program so your stuff gets drawn properly. Exactly how you do that depends on exactly what you want to happen.
Option 1: Only call the background() function once.
If you just want a black background at the beginning, and everything you do from the draw() function should still add up, then maybe you just want to call the background() function once. You could do it as the last line in your setup() function, for example.
Option 2: Store everything you want to draw in a data structure.
This is probably the most typical case. If you want a background to be drawn behind shapes that are moving around, you're going to have to store those shapes in some kind of data structure, and then draw all of them every single frame.
Option 3: Draw to an off-screen image, and then draw that image on top of your background.
This is a bit of a mix between the first two options. You can draw everything (except the background) to an off-screen PImage, and then draw the background to the screen, then draw the image to the screen. This allows you to have a background that changes colors without having to redraw everything else.
Which option you choose really depends on exactly what you want to happen.
I am making an object move in it's update() and turn left right up down according to user input. All I want is to make a spotlight follow the object.
Object's Rotation: 0,180,0
SpotLight's Rotation: 90,0,0
Since the rotations are different( and they need to be like that), I cannot make the light follow the object.
code :
function Update () {
SetControl(); // Input Stuff...
transform.Translate (0, 0, objectSpeed*Time.deltaTime);
lightView.transform.eulerAngles=this.transform.eulerAngles;
lightView.transform.Rotate=this.transform.eulerAngles;
lightView.transform.Translate(snakeSpeed*Time.deltaTime,0, 0); //THIS IS INCORRECT
}
lightView is simply pointing to the SpotLight.
What your looking for is the Unity method Transform.lookAt.
Place the following script on the spotlight. This code will make the object it is attached to, look at another object.
// Drag another object onto it to make the camera look at it.
var target : Transform;
// Rotate the camera every frame so it keeps looking at the target
function Update() {
transform.LookAt(target);
}
All I want is to make a spotlight follow the object.
This is a two-step process. First, find the coordinate position (in world coordinates) of your target. Second, apply that position plus an offset to your spotlight. Since your light is rotated 90° along the x-axis, I assume your light is above and looking down.
var offset = new Vector3(0, 5, 0);
function Update()
{
// Move this object
transform.Translate (0, 0, objectSpeed*Time.deltaTime);
// Move the light to transform's position + offset.
// Note that the light's rotation has already been set and does
// not need to be re-set each frame.
lightView.transform.position = transform.position + offset;
}
If you want a smoother "following" action, do a linear interpolation over time. Replace
lightView.transform.position = transform.position + offset;
with
lightView.transform.position = Vector3.Lerp(lightView.transform.position, transform.position + offset, Time.deltaTime * smoothingFactor);
where smoothingFactor is any float.
As an aside, it is near death to call transform.* in any kind of recurring game loop, because GameObject.transform is actually a get property that does a component search. Most Unity documentation recommends you cache the transform variable first.
Better code:
var myTrans = transform; // Cache the transform
var lightTrans = lightView.transform;
var offset = new Vector3(0, 5, 0);
function Update()
{
// Move this object
myTrans.Translate (0, 0, objectSpeed*Time.deltaTime);
// Move the light to transform's position + offset.
// Note that the light's rotation has already been set and does
// not need to be re-set each frame.
lightTrans.position = myTrans.position + offset;
}