//init variables
var canvasSize,zoom;
var dragging = false;
var lastPos = [0,0];
var currentTool = 'pencil';
var currentToolTemp = 'pencil';
var pencilSize = 1;
var eraserSize = 1;
var prevBrushSize = 1;
var prevEraserSize = 1;
var dialogueOpen = false;
var documentCreated = false;

// Checkerboard management
// Checkerboard color 1
var firstCheckerBoardColor = 'rgba(179, 173, 182, 1)';
// Checkerboard color 2
var secondCheckerBoardColor = 'rgba(204, 200, 206, 1)';
// Square size for the checkerboard
var checkerBoardSquareSize = 16;
// Checkerboard canvas
var checkerBoardCanvas = document.getElementById('checkerboard');

//common elements
var brushPreview = document.getElementById('brush-preview');
var eyedropperPreview = document.getElementById('eyedropper-preview');
var canvasView = document.getElementById('canvas-view');
var colors = document.getElementsByClassName('color-button');
var colorsMenu = document.getElementById('colors-menu');
var popUpContainer = document.getElementById('pop-up-container');

// main canvas
var canvas = document.getElementById('pixel-canvas');
var context = canvas.getContext('2d');
var currentGlobalColor;

// Layers
var layers = [];
// Currently selected layer
var currentLayer;

// VFX layer used to draw previews of the selection and things like that
var VFXLayer;
// VFX canvas
var VFXCanvas = document.getElementById('vfx-canvas');

// TMP layer
var TMPLayer;
// TMP canvas
var TMPCanvas = document.getElementById('tmp-canvas');