This tutorial shows you how to create a basic platformer game in WoofJS where you can make a player jump. It also shows how to add gravity to a game so the player falls back to the ground, as shown in the example below.
Create a new project at woofjs.com and use the following code to implement this feature. Make sure you pay attention to the comments in the code that explain how it works.
setBackdropURL("http://www.codemahal.com/sprites/blue_background.png") var jump = 8 var platform = new Image({ url: "http://www.codemahal.com/sprites/platform_thick.gif", width: 100, height: 30, x: -50, y: 0 }) var player = new Image({ url: "http://www.codemahal.com/sprites/player.gif", width: 20, height: 30, x: -80, y: 40 }) // Check if user presses UP and player is touching platform onKeyDown(key => { if (key == 'UP' && player.touching(platform)) { jump = -5 after(0.2, "seconds", () => { jump = 5 }) } }) forever(() => { // Player movement if (keysDown.includes('RIGHT')) { player.move(2) } if (keysDown.includes('LEFT')) { player.move(-2) } // Bring player back to ground if ((jump < 0) || (!(player.touching(platform)))) { player.y -= jump; } })