// the game itself var game; // global object with all customizable options var gameOptions = { // radius of the big circle - the "planet" - in pixels bigCircleRadius: 250, // radius of the small circle, in pixels playerRadius: 25, // player speed, in degrees per frame playerSpeed: 1, // world gravity worldGravity: 0.8, // jump force. First element is the first jump, second element - if any - the double jump, third element - if any - the triple jump and so on jumpForce: [12, 9, 6], // spike size - width, height - in pixels spikeSize: [25, 50], // distance needed to consider the player close to a spike, in degrees closeToSpike: 10, // distance needed to consider the player far from a spike, in degrees farFromSpike: 35 } window.onload = function() { // game configuration object var gameConfig = { thpe: Phaser.CANVAS, width: 800, height: 800, scene: [playGame] } game = new Phaser.Game(gameConfig); window.focus() resize(); window.addEventListener("resize", resize, false); } class playGame extends Phaser.Scene{ constructor(){ super("PlayGame"); } preload(){ this.load.image("bigcircle", "bigcircle.png"); this.load.image("player", "player.png"); this.load.image("spike", "spike.png"); this.load.image("mask", "mask.png"); this.load.image("particle", "particle.png"); } create(){ // flag to see if it's game over this.gameOver = false; // adding a group which will contain all spikes this.spikeGroup = this.add.group(); // adding the big circle, the "planet", placed in the middle of the canvas this.bigCircle = this.add.sprite(game.config.width / 2, game.config.height / 2, "bigcircle"); this.bigCircle.displayWidth = gameOptions.bigCircleRadius * 2; this.bigCircle.displayHeight = gameOptions.bigCircleRadius * 2; // placing the player, just above the top of the "planet" this.player = this.add.sprite(game.config.width / 2, game.config.height / 2 - gameOptions.bigCircleRadius - gameOptions.playerRadius, "player"); this.player.displayWidth = gameOptions.playerRadius * 2; this.player.displayHeight = gameOptions.playerRadius * 2; // a few custom properties: currentAngle is the angle of the player this.player.currentAngle = -80; // jumpOffset is the amount of pixels to be added to player position when it jumps this.player.jumpOffset = 0; // how many jumps is the player doing? this.player.jumps = 0; // current jump force this.player.jumpForce = 0; // when the player clicks/taps on the canvas... this.input.on("pointerdown", function(e){ // can the player jump? if(this.player.jumps < gameOptions.jumpForce.length){ // player is jumping once more this.player.jumps ++; // adding the proper jump force to player's jumpForce property this.player.jumpForce = gameOptions.jumpForce[this.player.jumps - 1]; } }, this); // we are going to place nine spikes for(var i = 0; i < 9; i ++){ // adding the spike on the canvas var spike = this.add.sprite(0, 0, "spike"); // set spike origin point to left and horizontal middle spike.setOrigin(0, 0.5); // adding the spike to spike group this.spikeGroup.add(spike); // place the spike. Arguments are the spike itself and the quadrant of the big circle this.placeSpike(spike, Math.floor(i / 3)); } // adding the mask image which will act like a "fog" to hide and show spikes this.maskImage = this.add.sprite(game.config.width / 2, game.config.height / 2, "mask"); // creating a particle system uising "particle" image var particles = this.add.particles("particle"); // trail emitter configuration this.emitter = particles.createEmitter({ // particle speed - particles do not move speed: 0, // particle scale: from 1 to zero scale: { start: 1, end: 0 }, // particle alpha: from opaque to transparent alpha: { start: 1, end: 0 }, // particle frequency: one particle every 100 milliseconds frequency: 100, // particle lifespan: 1 second lifespan: 1000 }); // making the emitter follow the player this.emitter.startFollow(this.player); } // method to randomly place a spike into a quadrant placeSpike(spike, quadrant){ // choosing a random angle var randomAngle = Phaser.Math.Angle.WrapDegrees(Phaser.Math.Between(quadrant * 90, (quadrant + 1) * 90)); // this is the same random angle converted in radians var randomAngleRadians = Phaser.Math.DegToRad(randomAngle); // determining spike position according to its angle var spikeX = this.bigCircle.x + (gameOptions.bigCircleRadius - Phaser.Math.Between(4, 25)) * Math.cos(randomAngleRadians); var spikeY = this.bigCircle.y + (gameOptions.bigCircleRadius - Phaser.Math.Between(4, 25)) * Math.sin(randomAngleRadians); spike.x = spikeX; spike.y = spikeY; // saving spike's quadrant in a custom property spike.quadrant = quadrant; // setting spike angke spike.angle = randomAngle; // saving the three spike vertices in custom properties spike.top = new Phaser.Math.Vector2(spikeX + gameOptions.spikeSize[1] * Math.cos(randomAngleRadians), spikeY + gameOptions.spikeSize[1] * Math.sin(randomAngleRadians)); spike.base1 = new Phaser.Math.Vector2(spikeX + gameOptions.spikeSize[0] / 2 * Math.cos(randomAngleRadians + Math.PI / 2), spikeY + gameOptions.spikeSize[0] / 2 * Math.sin(randomAngleRadians + Math.PI / 2)); spike.base2 = new Phaser.Math.Vector2(spikeX + gameOptions.spikeSize[0] / 2 * Math.cos(randomAngleRadians - Math.PI / 2), spikeY + gameOptions.spikeSize[0] / 2 * Math.sin(randomAngleRadians - Math.PI / 2)); // is the player approaching to the spike? spike.approaching = false; } // method to be executed at each frame update(){ // are we playing? if(!this.gameOver){ // is the player jumping? if(this.player.jumps > 0){ // adjusting player jump offset this.player.jumpOffset += this.player.jumpForce; // decreasing jump force due to gravity this.player.jumpForce -= gameOptions.worldGravity; // if jumpOffset is less than zero, it means the player touched the ground if(this.player.jumpOffset < 0){ // setting jump offset to zero this.player.jumpOffset = 0; // player is not jumping anymore this.player.jumps = 0; // there is no jump force this.player.jumpForce = 0; } } // setting new player current angle according to current position and speed this.player.currentAngle = Phaser.Math.Angle.WrapDegrees(this.player.currentAngle + gameOptions.playerSpeed); // moving the mask image accordingly this.maskImage.angle = this.player.currentAngle + 90; // getting the same angle in radians var radians = Phaser.Math.DegToRad(this.player.currentAngle); // determining the distance from the center according to planet radius, player radius and jump offset var distanceFromCenter = (gameOptions.bigCircleRadius * 2 + gameOptions.playerRadius * 2) / 2 + this.player.jumpOffset; // position the player using trigonometry this.player.x = this.bigCircle.x + distanceFromCenter * Math.cos(radians); this.player.y = this.bigCircle.y + distanceFromCenter * Math.sin(radians); // determining the number of revolutions the player has to do move according to planet and player size var revolutions = (gameOptions.bigCircleRadius * 2) / (gameOptions.playerRadius * 2) + 1; // set player rotation according to current angle and the number of revolutions needed this.player.angle = this.player.currentAngle * revolutions; // looping through each spike, as child of spikeGroup this.spikeGroup.children.iterate(function(spike){ // getting angle difference between the spike and the player var angleDiff = this.getAngleDifference(spike.angle, this.player.currentAngle); // if the player is not approaching the spike and it's close enough... if(!spike.approaching && angleDiff < gameOptions.closeToSpike){ // player is approaching the spike spike.approaching = true; } // if the player is approaching the spike... if(spike.approaching){ // checking for collision between the player and the two triangle sizes if(this.distToSegmentSquared(new Phaser.Math.Vector2(this.player.x, this.player.y), gameOptions.playerRadius, spike.top, spike.base1) || this.distToSegmentSquared(new Phaser.Math.Vector2(this.player.x, this.player.y), gameOptions.playerRadius, spike.top, spike.base2)){ // game over man... this.gameOver = true; // stop leaving a trail this.emitter.stop(); // shaking the camera this.cameras.main.shake(800, 0.01); // waiting 2 seconds this.time.addEvent({ // delay, in milliseconds delay: 2000, // callback function, to restart the scene callback: function(){ this.scene.start("PlayGame"); }, // callback scope callbackScope: this }); // let's make an explosion, first we define the particle... var particles = this.add.particles("particle"); // ... then the emitter var emitter = particles.createEmitter({ // particle speed speed: { min: -50, max: 50 }, // particle size scale: { start: 0.2, end: 0.25 }, // particle alpha alpha: { start: 1, end: 0 }, // particle lifespan, in milliseconds lifespan: 2000 }) // create an explosion with 70 particles at player position emitter.explode(70, this.player.x, this.player.y); // hide the player this.player.visible = false; } // if we are getting too far from the spike... if(angleDiff > gameOptions.farFromSpike){ // recycle the spike and move it in a random position three quadrants further this.placeSpike(spike, (spike.quadrant + 3) % 4); } } }, this); } } // function to get the minimum difference between two angles a1 and a2 getAngleDifference(a1, a2){ var angleDifference = a1 - a2 angleDifference += (angleDifference > 180) ? -360 : (angleDifference < -180) ? 360 : 0 return Math.abs(angleDifference); } // function to get the distance between two points p1 and p2 getDistance(p1, p2){ return (p1.x - p2.x) * (p1.x - p2.x) + (p1.y - p2.y) * (p1.y - p2.y); } // function to determine if a circle is touching a line segment given the circle center, the radius and the points defining the segment distToSegmentSquared(circleCenter, circleRadius, segmentStart, segmentEnd){ var l2 = this.getDistance(segmentStart, segmentEnd); var t = ((circleCenter.x - segmentStart.x) * (segmentEnd.x - segmentStart.x) + (circleCenter.y - segmentStart.y) * (segmentEnd.y - segmentStart.y)) / l2; t = Math.max(0, Math.min(1, t)); var tX = segmentStart.x + t * (segmentEnd.x - segmentStart.x); var tY = segmentStart.y + t * (segmentEnd.y - segmentStart.y); var tPoint = { x: tX, y: tY } return this.getDistance(circleCenter, tPoint) < circleRadius * circleRadius; } } // pure javascript to scale the game function resize() { var canvas = document.querySelector("canvas"); var windowWidth = window.innerWidth; var windowHeight = window.innerHeight; var windowRatio = windowWidth / windowHeight; var gameRatio = game.config.width / game.config.height; if(windowRatio < gameRatio){ canvas.style.width = windowWidth + "px"; canvas.style.height = (windowWidth / gameRatio) + "px"; } else{ canvas.style.width = (windowHeight * gameRatio) + "px"; canvas.style.height = windowHeight + "px"; } }What should we add next? A score system with some collectible objects, meanwhile download the source code.
HTML5 prototype of a circular endless runner featuring double jump built with Phaser – adding particle trails, explosions and camera effects
Read all posts about "Circular endless runner" game
Here we go with another step in the creation of the circular endless runner built without using any physics engine.
Let’s make a small recap:
In step 1 we covered the basics of a circular endless runner featuring double jump only using trigonometry. With no physics engine involved in the creation, it’s easy to port it to other languages.
In step 2 we added obstacles, reusing them again and again to save resources while giving the feeling of an infinite runner.
In step 3 trigonometry strikes back as we handle collisions.
In step 4 triple, quadruple or even quintuple jumps have been added.
Now we are going to add some eye catching effects like a trail following the player, as well as a camera shake and an explosion when the player hits a spike.
Look at the result:
Click or tap to jump and double jump, or even to make a triple jump. Look at the trail and the explosion effect when the player dies.
Phaser features a built in camera shake effect, so actually creating the shake effect was a matter of one single line of code.
About the trail and the explosion, they are particle effects. Once configured the particle emitters, one was set as explosion, one was told to follow the player, and that’s it.
Look at the commented source code to have more information: