How can I move camera in matter.js - matter.js

Question

How can I move the camera to a specific position in matter.js?
I want the camera to follow my main character.
I tried this tutorial: http://brm.io/matter-js/demo/#views
but truth be told, I did not understand it.

Answer 1

I found how to make it: http://codepen.io/vanuatu/pen/VeQMpp
We need to control render bounds, like this:
//
hero = bubbleBall
// Follow Hero at X-axis
engine.render.bounds.min.x = centerX + hero.bounds.min.x
engine.render.bounds.max.x = centerX + hero.bounds.min.x + initialEngineBoundsMaxX
// Follow Hero at Y-axis
engine.render.bounds.min.y = centerY + hero.bounds.min.y
engine.render.bounds.max.y = centerY + hero.bounds.min.y + initialEngineBoundsMaxY
// Update Mouse
Mouse.setOffset(mouseConstraint.mouse, engine.render.bounds.min);
I hope that can help someone

Answer 2

An easier way to do it:
Render.lookAt(render, player, {
x: 1080,
y: 1920
});
x and y are the width and height of the render bounds.

Answer 3

First, let's start with this simple example :
// module aliases
var Engine = Matter.Engine,
Render = Matter.Render,
World = Matter.World,
Runner = Matter.Runner,
Bodies = Matter.Bodies;
var engine = Engine.create();
var runner = Runner.create();
// create a renderer
var render = Render.create({
element: document.body,
engine: engine,
runner: runner,
options: {
width: 1280,
height: 720
}
});
var vertices = [{ x : 50, y : 0},
{ x : 63, y : 38},
{ x : 100, y : 38},
{ x : 69, y : 59},
{ x : 82, y : 100},
{ x : 50, y : 75},
{ x : 18, y : 100},
{ x : 31, y : 59},
{ x : 0, y : 38},
{ x : 37, y : 38} ];
// add a star at center
var star = Matter.Vertices.create(vertices);
var starBody = Bodies.fromVertices(640, 360, star, {isStatic: true}, true);
// add all of the bodies to the world
World.add(engine.world, [ starBody]);
Render.run(render);
Runner.run(runner, engine);
You should see a little star at center, if you want to move the camera, your render needs to have bounds, modify the render instanciation as follow :
<pre><code>
var render = Render.create({
element: document.body,
engine: engine,
runner: runner,
options: {
width: 1280,
height: 720,
<b>hasBounds : true</b>
}
});
And use the Bounds module alias :
var Engine = Matter.Engine,
Render = Matter.Render,
World = Matter.World,
Runner = Matter.Runner,
Bodies = Matter.Bodies,
Bounds = Matter.Bounds;
Now you can translate the bounds of your render to move your camera :
let translate = {x : -100, y : -100}
Bounds.translate(render.bounds, translate);
What it does in fact is something like this :
function moveMatterJSCamera(offsetX, offsetY) {
render.bounds.min.x += offsetX;
render.bounds.max.x += offsetX;
render.bounds.min.y += offsetY;
render.bounds.max.y += offsetY;
}

Answer 4

I found that translating everything works too. like transX=-player.position.x and then doing Matter.Body.translate(body,{x:transX,y:0}) with all your bodies including the player

Answer 5

function track(){
Render.lookAt(render, player, {
x: 500,
y: 500
});
}
function repeatOften() {
track()
requestAnimationFrame(repeatOften);
}
requestAnimationFrame(repeatOften);