scripts/loaders.js
var Loaders = (function () {
"use strict";
var Colors;
Colors = (function () {
function rgb2xyz(rgb) {
var xyz;
xyz = rgb.map(function (value) {
value = value / 255;
return ((value > 0.04045) ? Math.pow((value + 0.055) / 1.055, 2.4) : value / 12.92) * 100;
});
return [xyz[0] * 0.4124 + xyz[1] * 0.3576 + xyz[2] * 0.1805, xyz[0] * 0.2126 + xyz[1] * 0.7152 + xyz[2] * 0.0722, xyz[0] * 0.0193 + xyz[1] * 0.1192 + xyz[2] * 0.9505];
}
function xyz2lab(xyz) {
var labX, labY, labZ;
function process(value) {
return (value > 0.008856) ? Math.pow(value, 1 / 3) : (7.787 * value) + (16 / 116);
}
labX = process(xyz[0] / 95.047);
labY = process(xyz[1] / 100);
labZ = process(xyz[2] / 108.883);
return [116 * labY - 16, 500 * (labX - labY), 200 * (labY - labZ)];
}
function rgb2lab(rgb) {
return xyz2lab(rgb2xyz(rgb));
}
function labDeltaE(lab1, lab2) {
return Math.sqrt(Math.pow(lab1[0] - lab2[0], 2) + Math.pow(lab1[1] - lab2[1], 2) + Math.pow(lab1[2] - lab2[2], 2));
}
function rgbDeltaE(rgb1, rgb2) {
return labDeltaE(rgb2lab(rgb1), rgb2lab(rgb2));
}
function labCompare(lab, palette) {
var i, match, value, lowest;
for (i = 0; i < palette.length; ++i) {
value = labDeltaE(lab, palette[i]);
if (i === 0 || value < lowest) {
match = i;
lowest = value;
}
}
return match;
}
return {
"rgb2xyz": rgb2xyz,
"xyz2lab": xyz2lab,
"rgb2lab": rgb2lab,
"labDeltaE": labDeltaE,
"rgbDeltaE": rgbDeltaE,
"labCompare": labCompare
};
}());
function srcToImageData(src, callback) {
var img;
img = new Image();
img.onload = function () {
var imgCanvas, imgCtx, imgImageData;
imgCanvas = ElementHelper.create("canvas", {"width": img.width, "height": img.height});
imgCtx = imgCanvas.getContext("2d");
imgCtx.drawImage(img, 0, 0);
imgImageData = imgCtx.getImageData(0, 0, imgCanvas.width, imgCanvas.height);
callback(imgImageData);
};
img.src = src;
}
function rgbaAt(imageData, x, y) {
var pos;
pos = (y * imageData.width + x) * 4;
if (pos >= imageData.length) {
return [0, 0, 0, 255];
}
return [imageData.data[pos], imageData.data[pos + 1], imageData.data[pos + 2], imageData.data[pos + 3]];
}
function loadImg(src, callback, palette, codepage, noblink) {
srcToImageData(src, function (imageData) {
var imgX, imgY, i, paletteLab, topRGBA, botRGBA, topPal, botPal, data;
for (paletteLab = [], i = 0; i < palette.COLORS.length; ++i) {
paletteLab[i] = Colors.rgb2lab([palette.COLORS[i][0], palette.COLORS[i][1], palette.COLORS[i][2]]);
}
data = new Uint8Array(Math.ceil(imageData.height / 2) * imageData.width * 3);
for (imgY = 0, i = 0; imgY < imageData.height; imgY += 2) {
for (imgX = 0; imgX < imageData.width; imgX += 1) {
topRGBA = rgbaAt(imageData, imgX, imgY);
botRGBA = rgbaAt(imageData, imgX, imgY + 1);
if (topRGBA[3] === 0 && botRGBA[3] === 0) {
data[i++] = codepage.NULL;
data[i++] = 0;
data[i++] = 0;
} else {
topPal = Colors.labCompare(Colors.rgb2lab(topRGBA), paletteLab);
botPal = Colors.labCompare(Colors.rgb2lab(botRGBA), paletteLab);
if (topPal === botPal) {
data[i++] = codepage.FULL_BLOCK;
data[i++] = topPal;
data[i++] = 0;
} else if (topPal < 8 && botPal >= 8) {
data[i++] = codepage.LOWER_HALF_BLOCK;
data[i++] = botPal;
data[i++] = topPal;
} else if ((topPal >= 8 && botPal < 8) || (topPal < 8 && botPal < 8)) {
data[i++] = codepage.UPPER_HALF_BLOCK;
data[i++] = topPal;
data[i++] = botPal;
} else if (topRGBA[3] === 0) {
data[i++] = codepage.LOWER_HALF_BLOCK;
data[i++] = botPal;
if (noblink) {
data[i++] = topPal;
} else {
data[i++] = topPal - 8;
}
} else {
data[i++] = codepage.UPPER_HALF_BLOCK;
data[i++] = topPal;
if (noblink) {
data[i++] = botPal;
} else {
data[i++] = botPal - 8;
}
}
}
}
}
callback({
"width": imageData.width,
"height": Math.ceil(imageData.height / 2),
"data": data,
"alpha": true
});
});
}
function File(bytes) {
var pos, SAUCE_ID, COMNT_ID, commentCount;
SAUCE_ID = new Uint8Array([0x53, 0x41, 0x55, 0x43, 0x45]);
COMNT_ID = new Uint8Array([0x43, 0x4F, 0x4D, 0x4E, 0x54]);
// Returns an 8-bit byte at the current byte position, <pos>. Also advances <pos> by a single byte. Throws an error if we advance beyond the length of the array.
this.get = function () {
if (pos >= bytes.length) {
throw "Unexpected end of file reached.";
}
return bytes[pos++];
};
// Same as get(), but returns a 16-bit byte. Also advances <pos> by two (8-bit) bytes.
this.get16 = function () {
var v;
v = this.get();
return v + (this.get() << 8);
};
// Same as get(), but returns a 32-bit byte. Also advances <pos> by four (8-bit) bytes.
this.get32 = function () {
var v;
v = this.get();
v += this.get() << 8;
v += this.get() << 16;
return v + (this.get() << 24);
};
// Exactly the same as get(), but returns a character symbol, instead of the value. e.g. 65 = "A".
this.getC = function () {
return String.fromCharCode(this.get());
};
// Returns a string of <num> characters at the current file position, and strips the trailing whitespace characters. Advances <pos> by <num> by calling getC().
this.getS = function (num) {
var string;
string = "";
while (num-- > 0) {
string += this.getC();
}
return string.replace(/\s+$/, '');
};
// Returns "true" if, at the current <pos>, a string of characters matches <match>. Does not increment <pos>.
this.lookahead = function (match) {
var i;
for (i = 0; i < match.length; ++i) {
if ((pos + i === bytes.length) || (bytes[pos + i] !== match[i])) {
break;
}
}
return i === match.length;
};
// Returns an array of <num> bytes found at the current <pos>. Also increments <pos>.
this.read = function (num) {
var t;
t = pos;
// If num is undefined, return all the bytes until the end of file.
num = num || this.size - pos;
while (++pos < this.size) {
if (--num === 0) {
break;
}
}
return bytes.subarray(t, pos);
};
// Sets a new value for <pos>. Equivalent to seeking a file to a new position.
this.seek = function (newPos) {
pos = newPos;
};
// Returns the value found at <pos>, without incrementing <pos>.
this.peek = function (num) {
num = num || 0;
return bytes[pos + num];
};
// Returns the the current position being read in the file, in amount of bytes. i.e. <pos>.
this.getPos = function () {
return pos;
};
// Returns true if the end of file has been reached. <this.size> is set later by the SAUCE parsing section, as it is not always the same value as the length of <bytes>. (In case there is a SAUCE record, and optional comments).
this.eof = function () {
return pos === this.size;
};
// Seek to the position we would expect to find a SAUCE record.
pos = bytes.length - 128;
// If we find "SAUCE".
if (this.lookahead(SAUCE_ID)) {
this.sauce = {};
// Read "SAUCE".
this.getS(5);
// Read and store the various SAUCE values.
this.sauce.version = this.getS(2); // String, maximum of 2 characters
this.sauce.title = this.getS(35); // String, maximum of 35 characters
this.sauce.author = this.getS(20); // String, maximum of 20 characters
this.sauce.group = this.getS(20); // String, maximum of 20 characters
this.sauce.date = this.getS(8); // String, maximum of 8 characters
this.sauce.fileSize = this.get32(); // unsigned 32-bit
this.sauce.dataType = this.get(); // unsigned 8-bit
this.sauce.fileType = this.get(); // unsigned 8-bit
this.sauce.tInfo1 = this.get16(); // unsigned 16-bit
this.sauce.tInfo2 = this.get16(); // unsigned 16-bit
this.sauce.tInfo3 = this.get16(); // unsigned 16-bit
this.sauce.tInfo4 = this.get16(); // unsigned 16-bit
// Initialize the comments array.
this.sauce.comments = [];
commentCount = this.get(); // unsigned 8-bit
this.sauce.flags = this.get(); // unsigned 8-bit
if (commentCount > 0) {
// If we have a value for the comments amount, seek to the position we'd expect to find them...
pos = bytes.length - 128 - (commentCount * 64) - 5;
// ... and check that we find a COMNT header.
if (this.lookahead(COMNT_ID)) {
// Read COMNT ...
this.getS(5);
// ... and push everything we find after that into our <this.sauce.comments> array, in 64-byte chunks, stripping the trailing whitespace in the getS() function.
while (commentCount-- > 0) {
this.sauce.comments.push(this.getS(64));
}
}
}
}
// Seek back to the start of the file, ready for reading.
pos = 0;
if (this.sauce) {
// If we have found a SAUCE record, and the fileSize field passes some basic sanity checks...
if (this.sauce.fileSize > 0 && this.sauce.fileSize < bytes.length) {
// Set <this.size> to the value set in SAUCE.
this.size = this.sauce.fileSize;
} else {
// If it fails the sanity checks, just assume that SAUCE record can't be trusted, and set <this.size> to the position where the SAUCE record begins.
this.size = bytes.length - 128;
}
} else {
// If there is no SAUCE record, assume that everything in <bytes> relates to an image.
this.size = bytes.length;
}
}
function ScreenData(width) {
var imageData, maxY, pos;
function binColor(ansiColor) {
switch (ansiColor) {
case 4:
return 1;
case 6:
return 3;
case 1:
return 4;
case 3:
return 6;
case 12:
return 9;
case 14:
return 11;
case 9:
return 12;
case 11:
return 14;
default:
return ansiColor;
}
}
this.reset = function () {
imageData = new Uint8Array(width * 100 * 3);
maxY = 0;
pos = 0;
};
this.reset();
function extendImageData(y) {
var newImageData;
newImageData = new Uint8Array(width * (y + 100) * 3 + imageData.length);
newImageData.set(imageData, 0);
imageData = newImageData;
}
this.set = function (x, y, charCode, fg, bg) {
pos = (y * width + x) * 3;
if (pos >= imageData.length) {
extendImageData(y);
}
imageData[pos] = charCode;
imageData[pos + 1] = binColor(fg);
imageData[pos + 2] = binColor(bg);
if (y > maxY) {
maxY = y;
}
};
this.getData = function () {
return imageData.subarray(0, width * (maxY + 1) * 3);
};
this.getHeight = function () {
return maxY + 1;
};
this.rowLength = width * 3;
}
function loadAnsi(bytes, icecolors) {
var file, escaped, escapeCode, j, code, values, columns, imageData, topOfScreen, x, y, savedX, savedY, foreground, background, bold, blink, inverse;
file = new File(bytes);
function resetAttributes() {
foreground = 7;
background = 0;
bold = false;
blink = false;
inverse = false;
}
resetAttributes();
function newLine() {
x = 1;
if (y === 26 - 1) {
++topOfScreen;
} else {
++y;
}
}
function setPos(newX, newY) {
x = Math.min(columns, Math.max(1, newX));
y = Math.min(26, Math.max(1, newY));
}
x = 1;
y = 1;
topOfScreen = 0;
escapeCode = "";
escaped = false;
columns = 80;
imageData = new ScreenData(columns);
function getValues() {
return escapeCode.substr(1, escapeCode.length - 2).split(";").map(function (value) {
var parsedValue;
parsedValue = parseInt(value, 10);
return isNaN(parsedValue) ? 1 : parsedValue;
});
}
while (!file.eof()) {
code = file.get();
if (escaped) {
escapeCode += String.fromCharCode(code);
if ((code >= 65 && code <= 90) || (code >= 97 && code <= 122)) {
escaped = false;
values = getValues();
if (escapeCode.charAt(0) === "[") {
switch (escapeCode.charAt(escapeCode.length - 1)) {
case "A": // Up cursor.
y = Math.max(1, y - values[0]);
break;
case "B": // Down cursor.
y = Math.min(26 - 1, y + values[0]);
break;
case "C": // Forward cursor.
if (x === columns) {
newLine();
}
x = Math.min(columns, x + values[0]);
break;
case "D": // Backward cursor.
x = Math.max(1, x - values[0]);
break;
case "H": // Set the cursor position by calling setPos(), first <y>, then <x>.
if (values.length === 1) {
setPos(1, values[0]);
} else {
setPos(values[1], values[0]);
}
break;
case "J": // Clear screen.
if (values[0] === 2) {
x = 1;
y = 1;
imageData.reset();
}
break;
case "K": // Clear until the end of line.
for (j = x - 1; j < columns; ++j) {
imageData.set(j, y - 1 + topOfScreen, 0, 0);
}
break;
case "m": // Attributes, work through each code in turn.
for (j = 0; j < values.length; ++j) {
if (values[j] >= 30 && values[j] <= 37) {
foreground = values[j] - 30;
} else if (values[j] >= 40 && values[j] <= 47) {
background = values[j] - 40;
} else {
switch (values[j]) {
case 0: // Reset attributes
resetAttributes();
break;
case 1: // Bold
bold = true;
break;
case 5: // Blink
blink = true;
break;
case 7: // Inverse
inverse = true;
break;
case 22: // Bold off
bold = false;
break;
case 25: // Blink off
blink = false;
break;
case 27: // Inverse off
inverse = false;
break;
}
}
}
break;
case "s": // Save the current <x> and <y> positions.
savedX = x;
savedY = y;
break;
case "u": // Restore the current <x> and <y> positions.
x = savedX;
y = savedY;
break;
}
}
escapeCode = "";
}
} else {
switch (code) {
case 10: // Lone linefeed (LF).
newLine();
break;
case 13: // Carriage Return, and Linefeed (CRLF)
if (file.peek() === 0x0A) {
file.read(1);
newLine();
}
break;
case 26: // Ignore eof characters until the actual end-of-file, or sauce record has been reached.
break;
default:
if (code === 27 && file.peek() === 0x5B) {
escaped = true;
} else {
if (!inverse) {
imageData.set(x - 1, y - 1 + topOfScreen, code, bold ? (foreground + 8) : foreground, (icecolors && blink) ? (background + 8) : background);
} else {
imageData.set(x - 1, y - 1 + topOfScreen, code, bold ? (background + 8) : background, (icecolors && blink) ? (foreground + 8) : foreground);
}
if (++x === columns + 1) {
newLine();
}
}
}
}
}
return {
"width": columns,
"height": imageData.getHeight(),
"data": imageData.getData()
};
}
// A function to parse a sequence of bytes representing an XBiN file format.
function loadXbin(bytes) {
var file, header, imageData, output, i, j;
// This function is called to parse the XBin header.
function XBinHeader(file) {
var flags;
// Look for the magic number, throw an error if not found.
if (file.getS(4) !== "XBIN") {
throw "File ID does not match.";
}
if (file.get() !== 26) {
throw "File ID does not match.";
}
// Get the dimensions of the image...
this.width = file.get16();
this.height = file.get16();
// ... and the height of the font, if included.
this.fontHeight = file.get();
// Sanity check for the font height, throw an error if failed.
if (this.fontHeight === 0 || this.fontHeight > 32) {
throw "Illegal value for the font height (" + this.fontHeight + ").";
}
// Retrieve the flags.
flags = file.get();
// Check to see if a palette and font is included.
this.palette = ((flags & 1) === 1);
this.font = ((flags & 2) === 2);
// Sanity check for conflicting information in font settings.
if (this.fontHeight !== 16 && !this.font) {
throw "A non-standard font size was defined, but no font information was included with the file.";
}
// Check to see if the image data is <compressed>, if non-blink mode is set, <nonBlink>, and if 512 characters are included with the font data. <char512>.
this.compressed = ((flags & 4) === 4);
this.nonBlink = ((flags & 8) === 8);
this.char512 = ((flags & 16) === 16);
}
// Routine to decompress data found in an XBin <file>, which contains a Run-Length encoding scheme. Needs to know the current <width> and <height> of the image.
function uncompress(file, width, height) {
var uncompressed, p, repeatAttr, repeatChar, count;
// Initialize the data used to store the image, each text character has two bytes, one for the character code, and the other for the attribute.
uncompressed = new Uint8Array(width * height * 2);
i = 0;
while (i < uncompressed.length) {
p = file.get(); // <p>, the current code under inspection.
count = p & 63; // <count>, the times data is repeated
switch (p >> 6) { // Look at which RLE scheme to use
case 1: // Handle repeated character code.
for (repeatChar = file.get(), j = 0; j <= count; ++j) {
uncompressed[i++] = repeatChar;
uncompressed[i++] = file.get();
}
break;
case 2: // Handle repeated attributes.
for (repeatAttr = file.get(), j = 0; j <= count; ++j) {
uncompressed[i++] = file.get();
uncompressed[i++] = repeatAttr;
}
break;
case 3: // Handle repeated character code and attributes.
for (repeatChar = file.get(), repeatAttr = file.get(), j = 0; j <= count; ++j) {
uncompressed[i++] = repeatChar;
uncompressed[i++] = repeatAttr;
}
break;
default: // Handle no RLE.
for (j = 0; j <= count; ++j) {
uncompressed[i++] = file.get();
uncompressed[i++] = file.get();
}
}
}
return uncompressed; // Return the final, <uncompressed> data.
}
// Convert the bytes to a File() object, and reader the settings in the header, by calling XBinHeader().
file = new File(bytes);
header = new XBinHeader(file);
// If palette information is included, read it immediately after the header, if not, use the default palette used for BIN files.
if (header.palette) {
file.read(48);
}
// If font information is included, read it, if not, use the default 80x25 font.
if (header.font) {
file.read(header.fontHeight * 256);
}
// Fetch the image data, and uncompress if necessary.
imageData = header.compressed ? uncompress(file, header.width, header.height) : file.read(header.width * header.height * 2);
output = new Uint8Array(imageData.length / 2 * 3);
for (i = 0, j = 0; i < imageData.length; i += 2, j += 3) {
output[j] = imageData[i];
output[j + 1] = imageData[i + 1] & 15;
output[j + 2] = imageData[i + 1] >> 4;
}
return {
"width": header.width,
"height": header.height,
"data": output
};
}
function loadFile(file, callback, palette, codepage, noblink) {
var extension, reader;
extension = file.name.split(".").pop().toLowerCase();
reader = new FileReader();
reader.onload = function (data) {
switch (extension) {
case "png":
case "gif":
case "jpg":
case "jpeg":
loadImg(data.target.result, callback, palette, codepage, noblink);
break;
case "xb":
callback(loadXbin(new Uint8Array(data.target.result)));
break;
default:
callback(loadAnsi(new Uint8Array(data.target.result)));
}
};
switch (extension) {
case "png":
case "gif":
case "jpg":
case "jpeg":
reader.readAsDataURL(file);
break;
default:
reader.readAsArrayBuffer(file);
}
}
return {
"loadFile": loadFile
};
}());
