public/scripts/core.js
function createPalette(RGB6Bit) {
"use strict";
var RGBAColours = RGB6Bit.map((RGB6Bit) => {
return new Uint8Array(
[
RGB6Bit[0] << 2 | RGB6Bit[0] >> 4,
RGB6Bit[1] << 2 | RGB6Bit[1] >> 4,
RGB6Bit[2] << 2 | RGB6Bit[2] >> 4,
255
]
);
});
var foreground = 7;
var background = 0;
function getRGBAColour(index) {
return RGBAColours[index];
}
function getForegroundColour() {
return foreground;
}
function getBackgroundColour() {
return background;
}
function setForegroundColour(newForeground) {
foreground = newForeground;
document.dispatchEvent(new CustomEvent("onForegroundChange", {"detail": foreground}));
}
function setBackgroundColour(newBackground) {
background = newBackground;
document.dispatchEvent(new CustomEvent("onBackgroundChange", {"detail": background}));
}
return {
"getRGBAColour": getRGBAColour,
"getForegroundColour": getForegroundColour,
"getBackgroundColour": getBackgroundColour,
"setForegroundColour": setForegroundColour,
"setBackgroundColour": setBackgroundColour
};
}
function createDefaultPalette() {
"use strict";
return createPalette([
[0, 0, 0],
[0, 0, 42],
[0, 42, 0],
[0, 42, 42],
[42, 0, 0],
[42, 0, 42],
[42, 21, 0],
[42, 42, 42],
[21, 21, 21],
[21, 21, 63],
[21, 63, 21],
[21, 63, 63],
[63, 21, 21],
[63, 21, 63],
[63, 63, 21],
[63, 63, 63]
]);
}
function createPalettePreview(canvas) {
"use strict";
var imageData;
function updatePreview() {
var colour;
var foreground = palette.getRGBAColour(palette.getForegroundColour());
var background = palette.getRGBAColour(palette.getBackgroundColour());
for (var y = 0, i = 0; y < canvas.height; y++) {
for (var x = 0; x < canvas.width; x++, i += 4) {
if (y >= 10 && y < canvas.height - 10 && x > 10 && x < canvas.width - 10) {
colour = foreground;
} else {
colour = background;
}
imageData.data.set(colour, i);
}
}
canvas.getContext("2d").putImageData(imageData, 0, 0);
}
imageData = canvas.getContext("2d").createImageData(canvas.width, canvas.height);
updatePreview();
document.addEventListener("onForegroundChange", updatePreview);
document.addEventListener("onBackgroundChange", updatePreview);
return {
"setForegroundColour": updatePreview,
"setBackgroundColour": updatePreview
};
}
function createPalettePicker(canvas) {
"use strict";
var imageData = [];
function updateColor(index) {
var colour = palette.getRGBAColour(index);
for (var y = 0, i = 0; y < imageData[index].height; y++) {
for (var x = 0; x < imageData[index].width; x++, i += 4) {
imageData[index].data.set(colour, i);
}
}
canvas.getContext("2d").putImageData(imageData[index], (index > 7) ? (canvas.width / 2) : 0, (index % 8) * imageData[index].height);
}
function updatePalette() {
for (var i = 0; i < 16; i++) {
updateColor(i);
}
}
function mouseDown(evt) {
var rect = canvas.getBoundingClientRect();
var x = Math.floor((evt.clientX - rect.left) / (canvas.width / 2));
var y = Math.floor((evt.clientY - rect.top) / (canvas.height / 8));
var colourIndex = y + ((x === 0) ? 0 : 8);
if (evt.ctrlKey === false && evt.which != 3) {
palette.setForegroundColour(colourIndex);
} else {
palette.setBackgroundColour(colourIndex);
}
}
for (var i = 0; i < 16; i++) {
imageData[i] = canvas.getContext("2d").createImageData(canvas.width / 2, canvas.height / 8);
}
function keydown(evt) {
var keyCode = (evt.keyCode || evt.which);
if (keyCode >= 48 && keyCode <= 55) {
var num = keyCode - 48;
if (evt.ctrlKey === true) {
evt.preventDefault();
if (palette.getForegroundColour() === num) {
palette.setForegroundColour(num + 8);
} else {
palette.setForegroundColour(num);
}
} else if (evt.altKey) {
evt.preventDefault();
if (palette.getBackgroundColour() === num) {
palette.setBackgroundColour(num + 8);
} else {
palette.setBackgroundColour(num);
}
}
} else if (keyCode >= 37 && keyCode <= 40 && evt.ctrlKey === true){
evt.preventDefault();
switch(keyCode) {
case 37:
var colour = palette.getBackgroundColour();
colour = (colour === 0) ? 15 : (colour - 1);
palette.setBackgroundColour(colour);
break;
case 38:
var colour = palette.getForegroundColour();
colour = (colour === 0) ? 15 : (colour - 1);
palette.setForegroundColour(colour);
break;
case 39:
var colour = palette.getBackgroundColour();
colour = (colour === 15) ? 0 : (colour + 1);
palette.setBackgroundColour(colour);
break;
case 40:
var colour = palette.getForegroundColour();
colour = (colour === 15) ? 0 : (colour + 1);
palette.setForegroundColour(colour);
break;
default:
break;
}
}
}
updatePalette();
canvas.addEventListener("mousedown", mouseDown);
canvas.addEventListener("contextmenu", (evt) => {
evt.preventDefault();
});
document.addEventListener("keydown", keydown);
}
function loadImageAndGetImageData(url, callback) {
"use strict";
var imgElement = new Image();
imgElement.addEventListener("load", () => {
var canvas = createCanvas(imgElement.width, imgElement.height);
var ctx = canvas.getContext("2d");
ctx.drawImage(imgElement, 0, 0);
var imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
callback(imageData);
});
imgElement.addEventListener("error", () => {
callback(undefined);
});
imgElement.src = url;
}
function loadFontFromImage(fontName, letterSpacing, palette, callback) {
"use strict";
var fontData = {};
var fontGlyphs;
var alphaGlyphs;
var letterSpacingImageData;
function parseFontData(imageData) {
var fontWidth = imageData.width / 16;
var fontHeight = imageData.height / 16;
if ((fontWidth === 8) && (imageData.height % 16 === 0) && (fontHeight >= 1 && fontHeight <= 32)) {
var data = new Uint8Array(fontWidth * fontHeight * 256 / 8);
var k = 0;
for (var value = 0; value < 256; value += 1) {
var x = (value % 16) * fontWidth;
var y = Math.floor(value / 16) * fontHeight;
var pos = (y * imageData.width + x) * 4;
var i = 0;
while (i < fontWidth * fontHeight) {
data[k] = data[k] << 1;
if (imageData.data[pos] > 127) {
data[k] += 1;
}
if ((i += 1) % fontWidth === 0) {
pos += (imageData.width - 8) * 4;
}
if (i % 8 === 0) {
k += 1;
}
pos += 4;
}
}
return {
"width": fontWidth,
"height": fontHeight,
"data": data
};
}
return undefined;
}
function generateNewFontGlyphs() {
var canvas = createCanvas(fontData.width, fontData.height);
var ctx = canvas.getContext("2d");
var bits = new Uint8Array(fontData.width * fontData.height * 256);
for (var i = 0, k = 0; i < fontData.width * fontData.height * 256 / 8; i += 1) {
for (var j = 7; j >= 0; j -= 1, k += 1) {
bits[k] = (fontData.data[i] >> j) & 1;
}
}
fontGlyphs = new Array(16);
for (var foreground = 0; foreground < 16; foreground++) {
fontGlyphs[foreground] = new Array(16);
for (var background = 0; background < 16; background++) {
fontGlyphs[foreground][background] = new Array(256);
for (var charCode = 0; charCode < 256; charCode++) {
fontGlyphs[foreground][background][charCode] = ctx.createImageData(fontData.width, fontData.height);
for (var i = 0, j = charCode * fontData.width * fontData.height; i < fontData.width * fontData.height; i += 1, j += 1) {
var colour = palette.getRGBAColour((bits[j] === 1) ? foreground : background);
fontGlyphs[foreground][background][charCode].data.set(colour, i * 4);
}
}
}
}
alphaGlyphs = new Array(16);
for (var foreground = 0; foreground < 16; foreground++) {
alphaGlyphs[foreground] = new Array(256);
for (var charCode = 0; charCode < 256; charCode++) {
if (charCode === 220 || charCode === 223) {
var imageData = ctx.createImageData(fontData.width, fontData.height);
for (var i = 0, j = charCode * fontData.width * fontData.height; i < fontData.width * fontData.height; i += 1, j += 1) {
if (bits[j] === 1) {
imageData.data.set(palette.getRGBAColour(foreground), i * 4);
}
}
var alphaCanvas = createCanvas(imageData.width, imageData.height);
alphaCanvas.getContext("2d").putImageData(imageData, 0, 0);
alphaGlyphs[foreground][charCode] = alphaCanvas;
}
}
}
letterSpacingImageData = new Array(16);
for (var i = 0; i < 16; i++) {
var canvas = createCanvas(1, fontData.height);
var ctx = canvas.getContext("2d");
var imageData = ctx.getImageData(0, 0, 1, fontData.height);
var colour = palette.getRGBAColour(i);
for (var j = 0; j < fontData.height; j++) {
imageData.data.set(colour, j * 4);
}
letterSpacingImageData[i] = imageData;
}
}
function getWidth() {
if (letterSpacing === true) {
return fontData.width + 1;
}
return fontData.width;
}
function getHeight() {
return fontData.height;
}
function setLetterSpacing(newLetterSpacing) {
if (newLetterSpacing !== letterSpacing) {
generateNewFontGlyphs();
letterSpacing = newLetterSpacing;
document.dispatchEvent(new CustomEvent("onLetterSpacingChange", {"detail": letterSpacing}));
}
}
function getLetterSpacing() {
return letterSpacing;
}
loadImageAndGetImageData("fonts/" + fontName + ".png", (imageData) => {
if (imageData === undefined) {
callback(false);
} else {
var newFontData = parseFontData(imageData);
if (newFontData === undefined) {
callback(false);
} else {
fontData = newFontData;
generateNewFontGlyphs();
callback(true);
}
}
});
function draw(charCode, foreground, background, ctx, x, y) {
if (letterSpacing === true) {
ctx.putImageData(fontGlyphs[foreground][background][charCode], x * (fontData.width + 1), y * fontData.height);
if (charCode >= 192 && charCode <= 223) {
ctx.putImageData(fontGlyphs[foreground][background][charCode], x * (fontData.width + 1) + 1, y * fontData.height, fontData.width - 1, 0, 1, fontData.height);
} else {
ctx.putImageData(letterSpacingImageData[background], x * (fontData.width + 1) + 8, y * fontData.height);
}
} else {
ctx.putImageData(fontGlyphs[foreground][background][charCode], x * fontData.width, y * fontData.height);
}
}
function drawWithAlpha(charCode, foreground, ctx, x, y) {
if (letterSpacing === true) {
ctx.drawImage(alphaGlyphs[foreground][charCode], x * (fontData.width + 1), y * fontData.height);
if (charCode >= 192 && charCode <= 223) {
ctx.drawImage(alphaGlyphs[foreground][charCode], fontData.width - 1, 0, 1, fontData.height, x * (fontData.width + 1) + fontData.width, y * fontData.height, 1, fontData.height);
}
} else {
ctx.drawImage(alphaGlyphs[foreground][charCode], x * fontData.width, y * fontData.height);
}
}
return {
"getWidth": getWidth,
"getHeight": getHeight,
"setLetterSpacing": setLetterSpacing,
"getLetterSpacing": getLetterSpacing,
"draw": draw,
"drawWithAlpha": drawWithAlpha
};
}
function createTextArtCanvas(canvasContainer, callback) {
"use strict";
var columns = 80,
rows = 25,
iceColours = false,
imageData = new Uint16Array(columns * rows),
canvases,
ctxs,
offBlinkCanvases,
onBlinkCanvases,
offBlinkCtxs,
onBlinkCtxs,
blinkTimer,
blinkOn = false,
mouseButton = false,
currentUndo = [],
undoBuffer = [],
redoBuffer = [],
drawHistory = [];
function updateBeforeBlinkFlip(x, y) {
var dataIndex = y * columns + x;
var contextIndex = Math.floor(y / 25);
var contextY = y % 25;
var charCode = imageData[dataIndex] >> 8;
var background = (imageData[dataIndex] >> 4) & 15;
var foreground = imageData[dataIndex] & 15;
var shifted = background >= 8;
if (shifted === true) {
background -= 8;
}
if (blinkOn === true && shifted) {
font.draw(charCode, background, background, ctxs[contextIndex], x, contextY);
} else {
font.draw(charCode, foreground, background, ctxs[contextIndex], x, contextY);
}
}
function redrawGlyph(index, x, y) {
var contextIndex = Math.floor(y / 25);
var contextY = y % 25;
var charCode = imageData[index] >> 8;
var background = (imageData[index] >> 4) & 15;
var foreground = imageData[index] & 15;
if (iceColours === true) {
font.draw(charCode, foreground, background, ctxs[contextIndex], x, contextY);
} else {
if (background >= 8) {
background -= 8;
font.draw(charCode, foreground, background, offBlinkCtxs[contextIndex], x, contextY);
font.draw(charCode, background, background, onBlinkCtxs[contextIndex], x, contextY);
} else {
font.draw(charCode, foreground, background, offBlinkCtxs[contextIndex], x, contextY);
font.draw(charCode, foreground, background, onBlinkCtxs[contextIndex], x, contextY);
}
}
}
function redrawEntireImage() {
for (var y = 0, i = 0; y < rows; y++) {
for (var x = 0; x < columns; x++, i++) {
redrawGlyph(i, x, y);
}
}
}
function blink() {
if (blinkOn === false) {
blinkOn = true;
for (var i = 0; i < ctxs.length; i++) {
ctxs[i].drawImage(onBlinkCanvases[i], 0, 0);
}
} else {
blinkOn = false;
for (var i = 0; i < ctxs.length; i++) {
ctxs[i].drawImage(offBlinkCanvases[i], 0, 0);
}
}
}
function createCanvases() {
if (canvases !== undefined) {
canvases.forEach((canvas) => {
canvasContainer.removeChild(canvas);
});
}
canvases = [];
offBlinkCanvases = [];
offBlinkCtxs = [];
onBlinkCanvases = [];
onBlinkCtxs = [];
ctxs = [];
var fontWidth = font.getWidth();
var fontHeight = font.getHeight();
var canvasWidth = fontWidth * columns;
var canvasHeight = fontHeight * 25;
for (var i = 0; i < Math.floor(rows / 25); i++) {
var canvas = createCanvas(canvasWidth, canvasHeight);
canvases.push(canvas);
ctxs.push(canvas.getContext("2d"));
var onBlinkCanvas = createCanvas(canvasWidth, canvasHeight);
onBlinkCanvases.push(onBlinkCanvas);
onBlinkCtxs.push(onBlinkCanvas.getContext("2d"));
var offBlinkCanvas = createCanvas(canvasWidth, canvasHeight);
offBlinkCanvases.push(offBlinkCanvas);
offBlinkCtxs.push(offBlinkCanvas.getContext("2d"));
}
var canvasHeight = fontHeight * (rows % 25);
if (rows % 25 !== 0) {
var canvas = createCanvas(canvasWidth, canvasHeight);
canvases.push(canvas);
ctxs.push(canvas.getContext("2d"));
var onBlinkCanvas = createCanvas(canvasWidth, canvasHeight);
onBlinkCanvases.push(onBlinkCanvas);
onBlinkCtxs.push(onBlinkCanvas.getContext("2d"));
var offBlinkCanvas = createCanvas(canvasWidth, canvasHeight);
offBlinkCanvases.push(offBlinkCanvas);
offBlinkCtxs.push(offBlinkCanvas.getContext("2d"));
}
canvasContainer.style.width = canvasWidth + "px";
for (var i = 0; i < canvases.length; i++) {
canvasContainer.appendChild(canvases[i]);
}
if (blinkTimer !== undefined) {
clearInterval(blinkTimer);
blinkOn = false;
}
redrawEntireImage();
if (iceColours === false) {
blinkTimer = setInterval(blink, 250);
}
}
function updateTimer() {
if (blinkTimer !== undefined) {
clearInterval(blinkTimer);
}
if (iceColours === false) {
blinkOn = false;
blinkTimer = setInterval(blink, 500);
}
}
function setFont(fontName, callback) {
font = loadFontFromImage(fontName, font.getLetterSpacing(), palette, (success) => {
createCanvases();
redrawEntireImage();
document.dispatchEvent(new CustomEvent("onFontChange", {"detail": fontName}));
callback();
});
}
function resize(newColumnValue, newRowValue) {
if ((newColumnValue !== columns || newRowValue !== rows) && (newColumnValue > 0 && newRowValue > 0)) {
clearUndos();
var maxColumn = (columns > newColumnValue) ? newColumnValue : columns;
var maxRow = (rows > newRowValue) ? newRowValue : rows;
var newImageData = new Uint16Array(newColumnValue * newRowValue);
for (var y = 0; y < maxRow; y++) {
for (var x = 0; x < maxColumn; x++) {
newImageData[y * newColumnValue + x] = imageData[y * columns + x];
}
}
imageData = newImageData;
columns = newColumnValue;
rows = newRowValue;
createCanvases();
document.dispatchEvent(new CustomEvent("onTextCanvasSizeChange", {"detail": {"columns": columns, "rows": rows}}));
}
}
function getIceColours() {
return iceColours;
}
function setIceColours(newIceColours) {
if (iceColours !== newIceColours) {
iceColours = newIceColours;
updateTimer();
redrawEntireImage();
}
}
function onLetterSpacingChange(letterSpacing) {
createCanvases();
}
function getImage() {
var completeCanvas = createCanvas(font.getWidth() * columns, font.getHeight() * rows);
var y = 0;
var ctx = completeCanvas.getContext("2d");
((iceColours === true) ? canvases : offBlinkCanvases).forEach((canvas) => {
ctx.drawImage(canvas, 0, y);
y += canvas.height;
});
return completeCanvas;
}
function getImageData() {
return imageData;
}
function setImageData(newColumnValue, newRowValue, newImageData, newIceColours) {
clearUndos();
columns = newColumnValue;
rows = newRowValue;
imageData = newImageData;
if (iceColours !== newIceColours) {
iceColours = newIceColours;
updateTimer();
}
createCanvases();
redrawEntireImage();
document.dispatchEvent(new CustomEvent("onOpenedFile"));
}
function getColumns() {
return columns;
}
function getRows() {
return rows;
}
function clearUndos() {
currentUndo = [];
undoBuffer = [];
redoBuffer = [];
}
function clear() {
title.reset();
clearUndos();
imageData = new Uint16Array(columns * rows);
redrawEntireImage();
}
palette = createDefaultPalette();
font = loadFontFromImage("CP437 8x16", false, palette, (success) => {
createCanvases();
updateTimer();
callback();
});
function draw(index, charCode, foreground, background, x, y) {
currentUndo.push([index, imageData[index], x, y]);
imageData[index] = (charCode << 8) + (background << 4) + foreground;
drawHistory.push((index << 16) + imageData[index]);
}
function getBlock(x, y) {
var index = y * columns + x;
var charCode = imageData[index] >> 8;
var foregroundColour = imageData[index] & 15;
var backgroundColour = (imageData[index] >> 4) & 15;
return {
"x": x,
"y": y,
"charCode": charCode,
"foregroundColour": foregroundColour,
"backgroundColour": backgroundColour
};
}
function getHalfBlock(x, y) {
var textY = Math.floor(y / 2);
var index = textY * columns + x;
var foreground = imageData[index] & 15;
var background = (imageData[index] >> 4) & 15;
var upperBlockColour = 0;
var lowerBlockColour = 0;
var isBlocky = false;
var isVerticalBlocky = false;
var leftBlockColour;
var rightBlockColour;
switch (imageData[index] >> 8) {
case 0:
case 32:
case 255:
upperBlockColour = background;
lowerBlockColour = background;
isBlocky = true;
break;
case 220:
upperBlockColour = background;
lowerBlockColour = foreground;
isBlocky = true;
break;
case 221:
isVerticalBlocky = true;
leftBlockColour = foreground;
rightBlockColour = background;
break;
case 222:
isVerticalBlocky = true;
leftBlockColour = background;
rightBlockColour = foreground;
break;
case 223:
upperBlockColour = foreground;
lowerBlockColour = background;
isBlocky = true;
break;
case 219:
upperBlockColour = foreground;
lowerBlockColour = foreground;
isBlocky = true;
break;
default:
if (foreground === background) {
isBlocky = true;
upperBlockColour = foreground;
lowerBlockColour = foreground;
} else {
isBlocky = false;
}
}
return {
"x": x,
"y": y,
"textY": textY,
"isBlocky": isBlocky,
"upperBlockColour": upperBlockColour,
"lowerBlockColour": lowerBlockColour,
"halfBlockY": y % 2,
"isVerticalBlocky": isVerticalBlocky,
"leftBlockColour": leftBlockColour,
"rightBlockColour": rightBlockColour
};
}
function drawHalfBlock(index, foreground, x, y, textY) {
var halfBlockY = y % 2;
var charCode = imageData[index] >> 8;
var currentForeground = imageData[index] & 15;
var currentBackground = (imageData[index] >> 4) & 15;
if (charCode === 219) {
if (currentForeground !== foreground) {
if (halfBlockY === 0) {
draw(index, 223, foreground, currentForeground, x, textY);
} else {
draw(index, 220, foreground, currentForeground, x, textY);
}
}
} else if (charCode !== 220 && charCode !== 223) {
if (halfBlockY === 0) {
draw(index, 223, foreground, currentBackground, x, textY);
} else {
draw(index, 220, foreground, currentBackground, x, textY);
}
} else {
if (halfBlockY === 0) {
if (charCode === 223) {
if (currentBackground === foreground) {
draw(index, 219, foreground, 0, x, textY);
} else {
draw(index, 223, foreground, currentBackground, x, textY);
}
} else if (currentForeground === foreground) {
draw(index, 219, foreground, 0, x, textY);
} else {
draw(index, 223, foreground, currentForeground, x, textY);
}
} else {
if (charCode === 220) {
if (currentBackground === foreground) {
draw(index, 219, foreground, 0, x, textY);
} else {
draw(index, 220, foreground, currentBackground, x, textY);
}
} else if (currentForeground === foreground) {
draw(index, 219, foreground, 0, x, textY);
} else {
draw(index, 220, foreground, currentForeground, x, textY);
}
}
}
}
document.addEventListener("onLetterSpacingChange", onLetterSpacingChange);
function getXYCoords(clientX, clientY, callback) {
var rect = canvasContainer.getBoundingClientRect();
var x = Math.floor((clientX - rect.left) / font.getWidth());
var y = Math.floor((clientY - rect.top) / font.getHeight());
var halfBlockY = Math.floor((clientY - rect.top) / font.getHeight() * 2);
callback(x, y, halfBlockY);
}
canvasContainer.addEventListener("mousedown", (evt) => {
mouseButton = true;
getXYCoords(evt.clientX, evt.clientY, (x, y, halfBlockY) => {
if (evt.altKey === true) {
sampleTool.sample(x, halfBlockY);
} else {
document.dispatchEvent(new CustomEvent("onTextCanvasDown", {"detail": {"x": x, "y": y, "halfBlockY": halfBlockY, "leftMouseButton": (evt.button === 0 && evt.ctrlKey !== true), "rightMouseButton": (evt.button === 2 || evt.ctrlKey === true)}}));
}
});
});
canvasContainer.addEventListener("contextmenu", (evt) => {
evt.preventDefault();
});
canvasContainer.addEventListener("mousemove", (evt) => {
evt.preventDefault();
if (mouseButton === true) {
getXYCoords(evt.clientX, evt.clientY, (x, y, halfBlockY) => {
document.dispatchEvent(new CustomEvent("onTextCanvasDrag", {"detail": {"x": x, "y": y, "halfBlockY": halfBlockY, "leftMouseButton": (evt.button === 0 && evt.ctrlKey !== true), "rightMouseButton": (evt.button === 2 || evt.ctrlKey === true)}}));
});
}
});
canvasContainer.addEventListener("mouseup", (evt) => {
evt.preventDefault();
if (mouseButton === true) {
mouseButton = false;
document.dispatchEvent(new CustomEvent("onTextCanvasUp", {}));
}
});
canvasContainer.addEventListener("mouseenter", (evt) => {
evt.preventDefault();
if (mouseButton === true && (evt.which === 0 || evt.buttons === 0)) {
mouseButton = false;
document.dispatchEvent(new CustomEvent("onTextCanvasUp", {}));
}
});
function sendDrawHistory() {
worker.draw(drawHistory);
drawHistory = [];
}
function undo() {
if (currentUndo.length > 0) {
undoBuffer.push(currentUndo);
currentUndo = [];
}
if (undoBuffer.length > 0) {
var currentRedo = [];
var undoChunk = undoBuffer.pop();
for (var i = undoChunk.length - 1; i >= 0; i--) {
var undo = undoChunk.pop();
if (undo[0] < imageData.length) {
currentRedo.push([undo[0], imageData[undo[0]], undo[2], undo[3]]);
imageData[undo[0]] = undo[1];
drawHistory.push((undo[0] << 16) + undo[1]);
if (iceColours === false) {
updateBeforeBlinkFlip(undo[2], undo[3]);
}
redrawGlyph(undo[0], undo[2], undo[3]);
}
}
redoBuffer.push(currentRedo);
sendDrawHistory();
}
}
function redo() {
if (redoBuffer.length > 0) {
var redoChunk = redoBuffer.pop();
for (var i = redoChunk.length - 1; i >= 0; i--) {
var redo = redoChunk.pop();
if (redo[0] < imageData.length) {
currentUndo.push([redo[0], imageData[redo[0]], redo[2], redo[3]]);
imageData[redo[0]] = redo[1];
drawHistory.push((redo[0] << 16) + redo[1]);
if (iceColours === false) {
updateBeforeBlinkFlip(redo[2], redo[3]);
}
redrawGlyph(redo[0], redo[2], redo[3]);
}
}
undoBuffer.push(currentUndo);
currentUndo = [];
sendDrawHistory();
}
}
function startUndo() {
if (currentUndo.length > 0) {
undoBuffer.push(currentUndo);
currentUndo = [];
}
redoBuffer = [];
}
function optimiseBlocks(blocks) {
blocks.forEach((block) => {
var index = block[0];
var attribute = imageData[index];
var background = (attribute >> 4) & 15;
if (background >= 8) {
switch (attribute >> 8) {
case 0:
case 32:
case 255:
draw(index, 219, background, 0, block[1], block[2]);
break;
case 219:
draw(index, 219, (attribute & 15), 0, block[1], block[2]);
break;
case 221:
var foreground = (attribute & 15);
if (foreground < 8) {
draw(index, 222, background, foreground, block[1], block[2]);
}
break;
case 222:
var foreground = (attribute & 15);
if (foreground < 8) {
draw(index, 221, background, foreground, block[1], block[2]);
}
break;
case 223:
var foreground = (attribute & 15);
if (foreground < 8) {
draw(index, 220, background, foreground, block[1], block[2]);
}
break;
case 220:
var foreground = (attribute & 15);
if (foreground < 8) {
draw(index, 223, background, foreground, block[1], block[2]);
}
break;
default:
break;
}
}
});
}
function drawBlocks(blocks) {
blocks.forEach((block) => {
if (iceColours === false) {
updateBeforeBlinkFlip(block[1], block[2]);
}
redrawGlyph(block[0], block[1], block[2]);
});
}
function undoWithoutSending() {
for (var i = currentUndo.length - 1; i >= 0; i--) {
var undo = currentUndo.pop();
imageData[undo[0]] = undo[1];
}
drawHistory = [];
}
function drawEntryPoint(callback, optimise) {
var blocks = [];
callback(function (charCode, foreground, background, x, y) {
var index = y * columns + x;
blocks.push([index, x, y]);
draw(index, charCode, foreground, background, x, y);
});
if (optimise) {
optimiseBlocks(blocks);
}
drawBlocks(blocks);
sendDrawHistory();
}
function drawHalfBlockEntryPoint(callback) {
var blocks = [];
callback(function (foreground, x, y) {
var textY = Math.floor(y / 2);
var index = textY * columns + x;
blocks.push([index, x, textY]);
drawHalfBlock(index, foreground, x, y, textY);
});
optimiseBlocks(blocks);
drawBlocks(blocks);
sendDrawHistory();
}
function deleteArea(x, y, width, height, background) {
var maxWidth = x + width;
var maxHeight = y + height;
drawEntryPoint(function (draw) {
for (var dy = y; dy < maxHeight; dy++) {
for (var dx = x; dx < maxWidth; dx++) {
draw(0, 0, background, dx, dy);
}
}
});
}
function getArea(x, y, width, height) {
var data = new Uint16Array(width * height);
for (var dy = 0, j = 0; dy < height; dy++) {
for (var dx = 0; dx < width; dx++, j++) {
var i = (y + dy) * columns + (x + dx);
data[j] = imageData[i];
}
}
return {
"data": data,
"width": width,
"height": height
};
}
function setArea(area, x, y) {
var maxWidth = Math.min(area.width, columns - x);
var maxHeight = Math.min(area.height, rows - y);
drawEntryPoint(function (draw) {
for (var py = 0; py < maxHeight; py++) {
for (var px = 0; px < maxWidth; px++) {
var attrib = area.data[py * area.width + px];
draw(attrib >> 8, attrib & 15, (attrib >> 4) & 15, x + px, y + py);
}
}
});
}
function quickDraw(blocks) {
blocks.forEach((block) => {
if (imageData[block[0]] !== block[1]) {
imageData[block[0]] = block[1];
if (iceColours === false) {
updateBeforeBlinkFlip(block[2], block[3]);
}
redrawGlyph(block[0], block[2], block[3]);
}
});
}
return {
"resize": resize,
"redrawEntireImage": redrawEntireImage,
"setFont": setFont,
"getIceColours": getIceColours,
"setIceColours": setIceColours,
"getImage": getImage,
"getImageData": getImageData,
"setImageData": setImageData,
"getColumns": getColumns,
"getRows": getRows,
"clear": clear,
"draw": drawEntryPoint,
"getBlock": getBlock,
"getHalfBlock": getHalfBlock,
"drawHalfBlock": drawHalfBlockEntryPoint,
"startUndo": startUndo,
"undo": undo,
"redo": redo,
"deleteArea": deleteArea,
"getArea": getArea,
"setArea": setArea,
"quickDraw": quickDraw
};
}
