CodeBook

// Interactive Javascript editor
// By Daniel Hooper
// Based on a talk by Bret Victor
//
// Alt+Drag numbers to change their values
// Have Fun!

var paralaxOffset = 732;
var paralaxSpeed = 4;
var forestHeight = 50;
var movementSpeed = 5;
var images;

framerate(50);
function circle(ctx,x,y,r){
    ctx.beginPath();
    ctx.arc(x, y, r, 0, Math.PI*2, true); 
    ctx.closePath();
    ctx.fill();
}

function draw(ctx) {

// Sky
    ctx.fillStyle = color(121,172,217);
    ctx.fillRect(0,0,500,500);

// Sun
    ctx.fillStyle=color(295,236,91);
	circle(ctx,385,121,56);

// Trees
    ctx.fillStyle = color(2,138,100);
	ctx.fillRect(0,500-forestHeight,500,forestHeight);

var offset  = -(Math.floor(paralaxOffset / 4)%538);
    if(offset > 0) { offset -= 538; }
	var foresty = 500-images[0].height-forestHeight;
    ctx.drawImage(images[0], offset,  foresty);
    ctx.drawImage(images[0], offset+538, foresty);

offset = -(Math.floor(paralaxOffset)%538);
    if(offset > 0) { offset -= 538; }

// telephone poles
	var poleY = 500 - images[1].height;
	ctx.drawImage(images[2], offset+538, poleY-140);
	ctx.drawImage(images[2], offset, poleY-140);

// grass
	ctx.drawImage(images[1], offset, poleY);
    ctx.drawImage(images[1], offset+538, poleY);

// Input
    if(Keys.left) {
        paralaxOffset -= movementSpeed;
    } else if(Keys.right) {
        paralaxOffset += movementSpeed;
    } else {
		paralaxOffset++;
	}
}

function getimg(src) {
    var i = new Image();
    i.src = "demoimages/"+src; 
    return i;
}

if (!images) {
    images = [];
    images[0] = getimg("forest.png");
    images[1] = getimg("grass.png");
    images[2] = getimg("pole2.png");
}