初始化

uni_modules/UniDevTools/node_modules/pngjs/lib/png.js

@@ -0,0 +1,173 @@
+'use strict';
+
+var util = require('util');
+var Stream = require('stream');
+var Parser = require('./parser-async');
+var Packer = require('./packer-async');
+var PNGSync = require('./png-sync');
+
+
+var PNG = exports.PNG = function(options) {
+  Stream.call(this);
+
+  options = options || {}; // eslint-disable-line no-param-reassign
+
+  // coerce pixel dimensions to integers (also coerces undefined -> 0):
+  this.width = options.width | 0;
+  this.height = options.height | 0;
+
+  this.data = this.width > 0 && this.height > 0 ?
+    new Buffer(4 * this.width * this.height) : null;
+
+  if (options.fill && this.data) {
+    this.data.fill(0);
+  }
+
+  this.gamma = 0;
+  this.readable = this.writable = true;
+
+  this._parser = new Parser(options);
+
+  this._parser.on('error', this.emit.bind(this, 'error'));
+  this._parser.on('close', this._handleClose.bind(this));
+  this._parser.on('metadata', this._metadata.bind(this));
+  this._parser.on('gamma', this._gamma.bind(this));
+  this._parser.on('parsed', function(data) {
+    this.data = data;
+    this.emit('parsed', data);
+  }.bind(this));
+
+  this._packer = new Packer(options);
+  this._packer.on('data', this.emit.bind(this, 'data'));
+  this._packer.on('end', this.emit.bind(this, 'end'));
+  this._parser.on('close', this._handleClose.bind(this));
+  this._packer.on('error', this.emit.bind(this, 'error'));
+
+};
+util.inherits(PNG, Stream);
+
+PNG.sync = PNGSync;
+
+PNG.prototype.pack = function() {
+
+  if (!this.data || !this.data.length) {
+    this.emit('error', 'No data provided');
+    return this;
+  }
+
+  process.nextTick(function() {
+    this._packer.pack(this.data, this.width, this.height, this.gamma);
+  }.bind(this));
+
+  return this;
+};
+
+
+PNG.prototype.parse = function(data, callback) {
+
+  if (callback) {
+    var onParsed, onError;
+
+    onParsed = function(parsedData) {
+      this.removeListener('error', onError);
+
+      this.data = parsedData;
+      callback(null, this);
+    }.bind(this);
+
+    onError = function(err) {
+      this.removeListener('parsed', onParsed);
+
+      callback(err, null);
+    }.bind(this);
+
+    this.once('parsed', onParsed);
+    this.once('error', onError);
+  }
+
+  this.end(data);
+  return this;
+};
+
+PNG.prototype.write = function(data) {
+  this._parser.write(data);
+  return true;
+};
+
+PNG.prototype.end = function(data) {
+  this._parser.end(data);
+};
+
+PNG.prototype._metadata = function(metadata) {
+  this.width = metadata.width;
+  this.height = metadata.height;
+
+  this.emit('metadata', metadata);
+};
+
+PNG.prototype._gamma = function(gamma) {
+  this.gamma = gamma;
+};
+
+PNG.prototype._handleClose = function() {
+  if (!this._parser.writable && !this._packer.readable) {
+    this.emit('close');
+  }
+};
+
+
+PNG.bitblt = function(src, dst, srcX, srcY, width, height, deltaX, deltaY) { // eslint-disable-line max-params
+  // coerce pixel dimensions to integers (also coerces undefined -> 0):
+  /* eslint-disable no-param-reassign */
+  srcX |= 0;
+  srcY |= 0;
+  width |= 0;
+  height |= 0;
+  deltaX |= 0;
+  deltaY |= 0;
+  /* eslint-enable no-param-reassign */
+
+  if (srcX > src.width || srcY > src.height || srcX + width > src.width || srcY + height > src.height) {
+    throw new Error('bitblt reading outside image');
+  }
+
+  if (deltaX > dst.width || deltaY > dst.height || deltaX + width > dst.width || deltaY + height > dst.height) {
+    throw new Error('bitblt writing outside image');
+  }
+
+  for (var y = 0; y < height; y++) {
+    src.data.copy(dst.data,
+      ((deltaY + y) * dst.width + deltaX) << 2,
+      ((srcY + y) * src.width + srcX) << 2,
+      ((srcY + y) * src.width + srcX + width) << 2
+    );
+  }
+};
+
+
+PNG.prototype.bitblt = function(dst, srcX, srcY, width, height, deltaX, deltaY) { // eslint-disable-line max-params
+
+  PNG.bitblt(this, dst, srcX, srcY, width, height, deltaX, deltaY);
+  return this;
+};
+
+PNG.adjustGamma = function(src) {
+  if (src.gamma) {
+    for (var y = 0; y < src.height; y++) {
+      for (var x = 0; x < src.width; x++) {
+        var idx = (src.width * y + x) << 2;
+
+        for (var i = 0; i < 3; i++) {
+          var sample = src.data[idx + i] / 255;
+          sample = Math.pow(sample, 1 / 2.2 / src.gamma);
+          src.data[idx + i] = Math.round(sample * 255);
+        }
+      }
+    }
+    src.gamma = 0;
+  }
+};
+
+PNG.prototype.adjustGamma = function() {
+  PNG.adjustGamma(this);
+};