I want to speed up my whole background if press the up & arrow keys.
I have tried to do it but do not work.
this.speed
is to control the speed for the background.
So I put an if statement and said if up arrow key pressed then put the speed to 10.(You can see the Code below)
This is my Code:
//Setting the canvas and context
var canvas = document.getElementById('background');
var context = canvas.getContext('2d');
//===========================
//ENTER: MOVING BACKGROUND
//===========================
//Creating one abstract object to hold all images
var imageRepository = new function() {
//Upload background image
this.background = new Image();
this.background.src = "http://fc07.deviantart.net/fs70/f/2013/174/3/e/recycled_texture_background_by_sandeep_m-d6aeau9.jpg";
};
//Abstract function that will hold most all other properties
function Drawable() {
this.init = function(x, y) {
// Default variables
this.x = x;
this.y = y;
};
this.speed = 0;
this.canvasWidth = 0;
this.canvasHeight = 0;
this.draw = function() {
this.keys = keypress_handler();
};
}
//Creating the background image and drawing it
function Background() {
this.speed = 1; // Resetting speed of background for animation (positive so top to bottom motion)
this.draw = function() {
//Setting velocity to y-component, since track needs to go from top to bottom
this.y += this.speed;
this.context.drawImage(imageRepository.background, this.x, this.y);
// Draw it again for animation, top edge of the first background
this.context.drawImage(imageRepository.background, this.x, this.y - this.canvasHeight);
// If one background ends, reset
if (this.y > this.canvasHeight)
this.y = 0;
};
}
// Make background have properties from Drawable function
Background.prototype = new Drawable();
//Makes object to hold everything else the game will have
function Game() {
this.init = function() {
// Gets canvas element
this.bgCanvas = document.getElementById('background');
// Sees if canvas is supported by the browser
if (this.bgCanvas.getContext) {
this.bgContext = this.bgCanvas.getContext('2d');
// Initialize objects to contain their context and canvas
Background.prototype.context = this.bgContext;
Background.prototype.canvasWidth = this.bgCanvas.width;
Background.prototype.canvasHeight = this.bgCanvas.height;
// Initialize the background image
this.background = new Background();
this.background.init(0,0); // Set draw point to 0,0
return true;
} else {
return false;
}
};
// Start the animation loop for the background
this.start = function() {
animate();
};
}
//Requests animation frame
function animate() {
requestAnimFrame( animate );
game.background.draw();
}
//Setting all animation frames required
window.requestAnimFrame = (function(){
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(callback, element){
window.setTimeout(callback, 1000 / 60);
};
})();
//Create the final object and run it
var game = new Game();
function init() {
if(game.init())
game.start();
}
$(document).keydown(function(e){
if(e.keyCode == 38) {
this.speed = 10;
});
}
This is the Code that i have included for the up arrow keys, but doesn't work:
$(document).keydown(function(e){
if(e.keyCode == 38) {
this.speed = 10;
});
}
Thanks