sovgvd / nodetello Goto Github PK

Hi @SovGVD

I've been combing through your repo trying to get something in JS to use the low-level packet API.

I had a question about this bit in your code:

// TODO... this string manipulation is soooo slow!
var tmp_roll     = "00000000000"+(parseInt(1024 + 660 * this.stickData.roll) & 0x07ff).toString(2); tmp_roll=tmp_roll.substr(-11);
var tmp_pitch    = "00000000000"+(parseInt(1024 + 660 * this.stickData.pitch) & 0x07ff).toString(2); tmp_pitch=tmp_pitch.substr(-11);
var tmp_throttle = "00000000000"+(parseInt(1024 + 660 * this.stickData.throttle) & 0x07ff).toString(2); tmp_throttle=tmp_throttle.substr(-11);
var tmp_yaw      = "00000000000"+(parseInt(1024 + 660 * this.stickData.yaw) & 0x07ff).toString(2); tmp_yaw=tmp_yaw.substr(-11);
//var tmp_boost    = "00000000000"+(parseInt(1024 + 660 * 0)).toString(2);

Why are you adding 11 0's and then substr'ing them right off immediately after?

I realise this is code ported from go & python and whatever else is out there, but I'm a bit confused about the stick position packets and that's the bit I need to get working :)

Cheers

Hi, when I ran node app.js on a Mac, I got:

Error: spawn mplayer ENOENT
    at Process.ChildProcess._handle.onexit (internal/child_process.js:238:19)
...

I solved this by installing mplayer (with brew install mplayer). Perhaps it might be worth mentioning this in the README in case others might come across it too?

The following code

is considered potentially dangerous because:

1. All numbers in JavaScript are represented as double¹, which means you can only have integers in the range [−2⁵³, +2⁵³],
2. (Most important) bitwise operators treat their operands as a sequence of 32 bits² and return a signed 32-bit integer³, so the code (fast << 44) | (yaw << 33) will not work as expected. (Actually, you can try 1 << 32 and see how it goes)

Since this code is used to control the drone, IMO it's really dangerous and may hurt users. How do you think?

Refs:

1. Number value - ECMAScript Latest Draft (ECMA-262)
2. Bitwise operators - MDN
3. The Left Shift Operator - ECMAScript Latest Draft (ECMA-262)

when I try to start the app.js with node app.js
the following error happens:

(node:25512) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead.
tello_control listening 0.0.0.0:51615
events.js:167
      throw er; // Unhandled 'error' event
      ^

Error: ENOENT: no such file or directory, open 'D:\nodetello\video\1535987841691.video.h264'
Emitted 'error' event at:
    at lazyFs.open (internal/fs/streams.js:273:12)
    at FSReqWrap.oncomplete (fs.js:139:20)

Hope to know if I am having an issue or not, any way to fix that? Thanks