add ansiimage and overlay image. fixes chjj#153.

lib/widgets/ansiimage.js

@@ -0,0 +1,144 @@
+/**
+ * ansiimage.js - render PNGS/GIFS as ANSI
+ * Copyright (c) 2013-2015, Christopher Jeffrey and contributors (MIT License).
+ * https://github.com/chjj/blessed
+ */
+
+/**
+ * Modules
+ */
+
+var cp = require('child_process')
+  , path = require('path')
+  , fs = require('fs');
+
+var helpers = require('../helpers');
+var colors = require('../colors');
+
+var Node = require('./node');
+var Box = require('./box');
+
+var tng = require('../../vendor/tng');
+
+/**
+ * ANSIImage
+ */
+
+function ANSIImage(options) {
+  var self = this;
+
+  if (!(this instanceof Node)) {
+    return new ANSIImage(options);
+  }
+
+  options = options || {};
+  options.shrink = true;
+
+  Box.call(this, options);
+
+  this.scale = this.options.scale || 1.0;
+  this.options.animate = this.options.animate !== false;
+  this._noFill = true;
+
+  if (this.options.file) {
+    this.setImage(this.options.file);
+  }
+
+  this.screen.on('prerender', function() {
+    var lpos = self.lpos;
+    if (!lpos) return;
+    // prevent image from blending with itself if there are alpha channels
+    self.screen.clearRegion(lpos.xi, lpos.xl, lpos.yi, lpos.yl);
+  });
+}
+
+ANSIImage.prototype.__proto__ = Box.prototype;
+
+ANSIImage.prototype.type = 'ansiimage';
+
+ANSIImage.curl = function(url) {
+  try {
+    return cp.execFileSync('curl',
+      ['-s', '-A', '', url],
+      { stdio: ['ignore', 'pipe', 'ignore'] });
+  } catch (e) {
+    ;
+  }
+  try {
+    return cp.execFileSync('wget',
+      ['-U', '', '-O', '-', url],
+      { stdio: ['ignore', 'pipe', 'ignore'] });
+  } catch (e) {
+    ;
+  }
+  throw new Error('curl or wget failed.');
+};
+
+ANSIImage.prototype.setImage = function(file) {
+  var self = this;
+  this.file = typeof file === 'string' ? file : null;
+  if (/^https?:/.test(file)) {
+    file = ANSIImage.curl(file);
+  }
+  var width = this.position.width;
+  var height = this.position.height;
+  if (width != null) {
+    width = this.width;
+  }
+  if (height != null) {
+    height = this.height;
+  }
+  try {
+    this.setContent('');
+    this.img = tng(file, {
+      colors: colors,
+      width: width,
+      height: height,
+      scale: this.scale,
+      ascii: this.options.ascii,
+      speed: this.options.speed,
+      filename: this.file
+    });
+    if (width == null || height == null) {
+      this.width = this.img.cellmap[0].length;
+      this.height = this.img.cellmap.length;
+    }
+    if (this.img.frames && this.options.animate) {
+      this.img.play(function(bmp, cellmap) {
+        self.cellmap = cellmap;
+        self.screen.render();
+      });
+    } else {
+      self.cellmap = self.img.cellmap;
+    }
+  } catch (e) {
+    this.setContent('Image Error: ' + e.message);
+    this.img = null;
+    this.cellmap = null;
+  }
+};
+
+ANSIImage.prototype.clearImage = function() {
+  this.setContent('');
+  this.img = null;
+  this.cellmap = null;
+};
+
+ANSIImage.prototype.render = function() {
+  var self = this;
+
+  var coords = this._render();
+  if (!coords) return;
+
+  if (this.img) {
+    this.img.renderElement(this.cellmap, this);
+  }
+
+  return coords;
+};
+
+/**
+ * Expose
+ */
+
+module.exports = ANSIImage;