pixel-editor/js/layers/Layer.js
2021-12-11 12:48:12 +01:00

319 lines
11 KiB
JavaScript

// TODO: add undo for layer drag n drop
/** Handler class for a single canvas (a single layer)
*
* @param width Canvas width
* @param height Canvas height
* @param canvas HTML canvas element or the ID of the canvas related to the layer
*/
class Layer {
static layerCount = 1;
static maxZIndex = 3;
static unusedIDs = [];
static currentID = 1;
static layerOptions = document.getElementById("layer-properties-menu");
// TODO: this is simply terrible. menuEntry can either be an HTML element, a string or undefined.
// If it's an HTML element it is added, if it's a string nothing happens, if it's undefined the
// first menuEntry is used (the one that appears on load)
constructor(width, height, canvas, menuEntry) {
// REFACTOR: the canvas should actually be a Canvas instance
this.canvas = Util.getElement(canvas);
this.canvas.width = width;
this.canvas.height = height;
// REFACTOR: the context could be an attribute of the canvas class, but it's a bit easier
// to just type layer.context, we should discuss this
this.context = this.canvas.getContext('2d');
this.isSelected = false;
this.isVisible = true;
this.isLocked = false;
this.oldLayerName = null;
if (typeof menuEntry == "string")
this.menuEntry = document.getElementById("layers-menu").firstElementChild;
else if (menuEntry !== undefined)
this.menuEntry = menuEntry;
let id = Layer.unusedIDs.pop();
if (id == null) {
id = Layer.currentID;
Layer.currentID++;
}
this.id = "layer" + id;
// Binding the events
if (this.menuEntry !== undefined) {
this.name = this.menuEntry.getElementsByTagName("p")[0].innerHTML;
this.menuEntry.id = "layer" + id;
this.menuEntry.onmouseover = () => this.hover();
this.menuEntry.onmouseout = () => this.unhover();
this.menuEntry.onclick = () => this.selectLayer();
this.menuEntry.getElementsByTagName("button")[0].onclick = () => this.toggleLock();
this.menuEntry.getElementsByTagName("button")[1].onclick = () => this.toggleVisibility();
this.menuEntry.addEventListener("mouseup", this.openOptionsMenu, false);
this.menuEntry.addEventListener("dragstart", this.layerDragStart, false);
this.menuEntry.addEventListener("drop", this.layerDragDrop, false);
this.menuEntry.addEventListener("dragover", this.layerDragOver, false);
this.menuEntry.addEventListener("dragleave", this.layerDragLeave, false);
this.menuEntry.addEventListener("dragend", this.layerDragEnd, false);
Events.onCustom("del", this.tryDelete.bind(this));
this.menuEntry.getElementsByTagName("canvas")[0].getContext('2d').imageSmoothingEnabled = false;
}
this.initialize();
}
hasCanvas() {
return this.menuEntry != null;
}
tryDelete() {
if (Input.getLastTarget() != this.menuEntry && Input.getLastTarget().parentElement != this.menuEntry)
return;
LayerList.deleteLayer();
}
// Initializes the canvas
initialize() {
//resize canvas
this.canvas.style.width = (this.canvas.width*currFile.zoom)+'px';
this.canvas.style.height = (this.canvas.height*currFile.zoom)+'px';
//show canvas
this.canvas.style.display = 'block';
//center canvas in window
this.canvas.style.left = 64+currFile.canvasView.clientWidth/2-(currFile.canvasSize[0]*currFile.zoom/2)+'px';
this.canvas.style.top = 48+currFile.canvasView.clientHeight/2-(currFile.canvasSize[1]*currFile.zoom/2)+'px';
this.context.imageSmoothingEnabled = false;
this.context.mozImageSmoothingEnabled = false;
}
rename() {
this.menuEntry.getElementsByTagName("p")[0].setAttribute("contenteditable", false);
if (this.oldLayerName != null) {
let name = this.menuEntry.getElementsByTagName("p")[0].innerHTML;
for (let i=0; i<currFile.layers.length; i++) {
if (name === currFile.layers[i].name) {
name += ' (1)';
i = 0;
}
}
this.name = name;
this.menuEntry.getElementsByTagName("p")[0].innerHTML = name;
new HistoryState().RenameLayer(this.oldLayerName, name, currFile.currentLayer);
this.oldLayerName = null;
}
}
hover() {
// Hides all the layers but the current one
for (let i=1; i<currFile.layers.length - nAppLayers; i++) {
if (currFile.layers[i] !== this) {
currFile.layers[i].canvas.style.opacity = 0.3;
}
}
}
unhover() {
// Shows all the layers again
for (let i=1; i<currFile.layers.length - nAppLayers; i++) {
if (currFile.layers[i] !== this) {
currFile.layers[i].canvas.style.opacity = 1;
}
}
}
setID(id) {
this.id = id;
if (this.menuEntry != null) {
this.menuEntry.id = id;
}
}
// Resizes canvas
resize() {
let newWidth = (this.canvas.width * currFile.zoom) + 'px';
let newHeight = (this.canvas.height *currFile.zoom)+ 'px';
this.canvas.style.width = newWidth;
this.canvas.style.height = newHeight;
}
setCanvasOffset (offsetLeft, offsetTop) {
//horizontal offset
var minXOffset = -currFile.canvasSize[0] * currFile.zoom;
var maxXOffset = window.innerWidth - 300;
if (offsetLeft < minXOffset)
this.canvas.style.left = minXOffset +'px';
else if (offsetLeft > maxXOffset)
this.canvas.style.left = maxXOffset +'px';
else
this.canvas.style.left = offsetLeft +'px';
//vertical offset
var minYOffset = -currFile.canvasSize[1] * currFile.zoom + 164;
var maxYOffset = window.innerHeight - 100;
if (offsetTop < minYOffset)
this.canvas.style.top = minYOffset +'px';
else if (offsetTop > maxYOffset)
this.canvas.style.top = maxYOffset +'px';
else
this.canvas.style.top = offsetTop +'px';
}
// Copies the otherLayer's position and size
copyData(otherLayer) {
this.canvas.style.width = otherLayer.canvas.style.width;
this.canvas.style.height = otherLayer.canvas.style.height;
this.canvas.style.left = otherLayer.canvas.style.left;
this.canvas.style.top = otherLayer.canvas.style.top;
}
selectLayer(hideOptions = true) {
if (hideOptions)
LayerList.closeOptionsMenu();
// Deselecting the old layer
currFile.currentLayer.deselectLayer();
// Selecting the current layer
this.isSelected = true;
this.menuEntry.classList.add("selected-layer");
currFile.currentLayer = this;
}
toggleLock() {
if (this.isLocked) {
this.unlock();
}
else {
this.lock();
}
}
toggleVisibility() {
if (this.isVisible) {
this.hide();
}
else {
this.show();
}
}
deselectLayer() {
this.isSelected = false;
this.menuEntry.classList.remove("selected-layer");
}
lock() {
this.isLocked = true;
this.menuEntry.getElementsByClassName("layer-button")[0].style.visibility = "visible";
this.menuEntry.getElementsByClassName("default-icon")[0].style.display = "none";
this.menuEntry.getElementsByClassName("edited-icon")[0].style.display = "inline-block";
}
unlock() {
this.isLocked = false;
this.menuEntry.getElementsByClassName("layer-button")[0].style.visibility = "hidden";
this.menuEntry.getElementsByClassName("default-icon")[0].style.display = "inline-block";
this.menuEntry.getElementsByClassName("edited-icon")[0].style.display = "none";
}
show() {
this.isVisible = true;
this.canvas.style.visibility = "visible";
this.menuEntry.getElementsByClassName("layer-button")[1].style.visibility = "hidden";
// Changing icon
this.menuEntry.getElementsByClassName("default-icon")[1].style.display = "inline-block";
this.menuEntry.getElementsByClassName("edited-icon")[1].style.display = "none";
}
hide() {
this.isVisible = false;
this.canvas.style.visibility = "hidden";
this.menuEntry.getElementsByClassName("layer-button")[1].style.visibility = "visible";
// Changing icon
this.menuEntry.getElementsByClassName("default-icon")[1].style.display = "none";
this.menuEntry.getElementsByClassName("edited-icon")[1].style.display = "inline-block";
}
updateLayerPreview() {
// Getting the canvas
let destination = this.menuEntry.getElementsByTagName("canvas")[0];
let widthRatio = currFile.canvasSize[0] / currFile.canvasSize[1];
let heightRatio = currFile.canvasSize[1] / currFile.canvasSize[0];
// Computing width and height for the preview image
let previewWidth = destination.width;
let previewHeight = destination.height;
// If the sprite is rectangular, I apply the ratio to the preview as well
if (widthRatio < 1) {
previewWidth = destination.width * widthRatio;
}
else if (widthRatio > 1) {
previewHeight = destination.height * heightRatio;
}
// La appiccico sulla preview
destination.getContext('2d').clearRect(0, 0, destination.width, destination.height);
destination.getContext('2d').drawImage(this.canvas,
// This is necessary to center the preview in the canvas
(destination.width - previewWidth) / 2, (destination.height - previewHeight) / 2,
previewWidth, previewHeight);
}
drawLine(x0,y0,x1,y1, brushSize) {
var dx = Math.abs(x1-x0);
var dy = Math.abs(y1-y0);
var sx = (x0 < x1 ? 1 : -1);
var sy = (y0 < y1 ? 1 : -1);
var err = dx-dy;
while (true) {
//set pixel
// If the current tool is the brush
if (ToolManager.currentTool().name == 'brush' || ToolManager.currentTool().name == 'rectangle' || ToolManager.currentTool().name == 'ellipse') {
// I fill the rect
currFile.currentLayer.context.fillRect(x0-Math.floor(brushSize/2), y0-Math.floor(brushSize/2), brushSize, brushSize);
} else if (ToolManager.currentTool().name == 'eraser') {
// In case I'm using the eraser I must clear the rect
currFile.currentLayer.context.clearRect(x0-Math.floor(brushSize/2), y0-Math.floor(brushSize/2), brushSize, brushSize);
}
//if we've reached the end goal, exit the loop
if ((x0==x1) && (y0==y1)) break;
var e2 = 2*err;
if (e2 >-dy) {
err -=dy;
x0+=sx;
}
if (e2 < dx) {
err +=dx;
y0+=sy;
}
}
}
}