# Latest

**URL:** https://discourse.processing.org/latest.md?no_subcategories=false&page=472

[Latest](https://discourse.processing.org/latest.md) · [Categories](https://discourse.processing.org/categories.md) · [Tags](https://discourse.processing.org/tags.md)

**Page:** 473

---

## [How to draw a Binary Tree?](https://discourse.processing.org/t/how-to-draw-a-binary-tree/12195)

<div class="topic-metadata">

**Author:** [@demsp](https://discourse.processing.org/u/demsp)\
**Replies:** 6\
**Last updated:** [June 21, 2019, 9:20pm UTC](https://discourse.processing.org/t/how-to-draw-a-binary-tree/12195 "2019-06-21T21:20:11Z")

</div>

This is an example of “Tree in Java”. Can i modify the Node\* class so that to draw the node like so class Node { int value; int x; // add x-coord int y; // add y-coord Node left; Node right; Node(int value, int x…

---

## [Retrieve data from google spreadsheet](https://discourse.processing.org/t/retrieve-data-from-google-spreadsheet/12230)

<div class="topic-metadata">

**Author:** [@jensemand](https://discourse.processing.org/u/jensemand)\
**Replies:** 1\
**Last updated:** [June 21, 2019, 8:21pm UTC](https://discourse.processing.org/t/retrieve-data-from-google-spreadsheet/12230 "2019-06-21T20:21:25Z")

</div>

Hi, I need to retrieve some data from google spreadsheet but i don’t know how i can get access to it

---

## [\[SOLVED\] PImage\[\] array inside class shows all images at once](https://discourse.processing.org/t/solved-pimage-array-inside-class-shows-all-images-at-once/12190)

<div class="topic-metadata">

**Author:** [@RealDwayneJ](https://discourse.processing.org/u/RealDwayneJ)\
**Replies:** 14\
**Last updated:** [June 21, 2019, 7:44pm UTC](https://discourse.processing.org/t/solved-pimage-array-inside-class-shows-all-images-at-once/12190 "2019-06-21T19:44:12Z")

</div>

Please note that this is just a portion of the full code. I made sure to isolate this portion only, with all its problems included. What it’s supposed to do: So, in the full code I have a program where you can hit a ce…

---

## [Array.length error](https://discourse.processing.org/t/array-length-error/12217)

<div class="topic-metadata">

**Author:** [@FlyingApple](https://discourse.processing.org/u/FlyingApple)\
**Replies:** 6\
**Last updated:** [June 21, 2019, 12:27pm UTC](https://discourse.processing.org/t/array-length-error/12217 "2019-06-21T12:27:45Z")

</div>

Whenever I do the array.length function I get the error "The global variable “length” does not exist. for (int i = 0; i \< walls.length; i++) { Wall wall = walls.get(i); wall.show(); } walls is an array of the…

---

## [Clip() flickering](https://discourse.processing.org/t/clip-flickering/12227)

<div class="topic-metadata">

**Author:** [@lsk](https://discourse.processing.org/u/lsk)\
**Replies:** 1\
**Last updated:** [June 21, 2019, 11:08am UTC](https://discourse.processing.org/t/clip-flickering/12227 "2019-06-21T11:08:57Z")

</div>

I want to create an effect, where I have 2 source images which are copied onto a destination image made up of n tiles and then slide the tiles to reveal the other image. The way I want to achieve this is by copying a ti…

---

## [Getting started with contribution: How to build from source?](https://discourse.processing.org/t/getting-started-with-contribution-how-to-build-from-source/3226)

<div class="topic-metadata">

**Author:** [@svr8](https://discourse.processing.org/u/svr8)\
**Replies:** 19\
**Last updated:** [June 21, 2019, 8:06am UTC](https://discourse.processing.org/t/getting-started-with-contribution-how-to-build-from-source/3226 "2019-06-21T08:06:36Z")

</div>

Hey! I want to build/run the source files given here: https://github.com/processing/processing. However, the github wiki page seems to be under development: https://github.com/processing/processing/wiki/Build-Instructio…

---

## [Creating a grid of toggle buttons](https://discourse.processing.org/t/creating-a-grid-of-toggle-buttons/12162)

<div class="topic-metadata">

**Author:** [@Col\_John\_Matrix](https://discourse.processing.org/u/Col_John_Matrix)\
**Replies:** 4\
**Last updated:** [June 21, 2019, 7:59am UTC](https://discourse.processing.org/t/creating-a-grid-of-toggle-buttons/12162 "2019-06-21T07:59:06Z")

</div>

Hello, I wish to create a GUI to control the ON/OFF state of an 8 by 8 array of LEDs. What I’d like the GUI to look like would be an 8 by 8 array of toggle buttons, one for each LED, to toggle each LED ON/OFF accordingl…

---

## [Threadsafe offscreen drawing?](https://discourse.processing.org/t/threadsafe-offscreen-drawing/12220)

<div class="topic-metadata">

**Author:** [@Rolf](https://discourse.processing.org/u/Rolf)\
**Replies:** 3\
**Last updated:** [June 21, 2019, 6:58am UTC](https://discourse.processing.org/t/threadsafe-offscreen-drawing/12220 "2019-06-21T06:58:36Z")

</div>

Here’s the idea I want to draw to a huge offscreen buffer usig thread(). Then I want to display the progress in the main window, in a scaled down size. Does not work, it displays the scaled down image, but only once t…

---

## [P5.js Object array of title names are not being recognized](https://discourse.processing.org/t/p5-js-object-array-of-title-names-are-not-being-recognized/12224)

<div class="topic-metadata">

**Author:** [@debxyz](https://discourse.processing.org/u/debxyz)\
**Replies:** 4\
**Last updated:** [June 21, 2019, 5:57am UTC](https://discourse.processing.org/t/p5-js-object-array-of-title-names-are-not-being-recognized/12224 "2019-06-21T05:57:05Z")

</div>

Before adding the stars I’m trying to figure out why the titles are not appearing on the book objects. I’m sure it’s a simple oversight on my part, but if anyone can help it is sincerely appreciated! var myBooks = \[ { …

---

## [Trouble with if statments](https://discourse.processing.org/t/trouble-with-if-statments/12210)

<div class="topic-metadata">

**Author:** [@Asterioapo](https://discourse.processing.org/u/Asterioapo)\
**Replies:** 2\
**Last updated:** [June 20, 2019, 11:55pm UTC](https://discourse.processing.org/t/trouble-with-if-statments/12210 "2019-06-20T23:55:43Z")

</div>

Quite new to Processing and am trying to create a sort of create a character program where you chose options for them. I can get the options to cycle but am struggling to figure out the code to use so that if i press a k…

---

## [Rotating an image in the direction of the mouse](https://discourse.processing.org/t/rotating-an-image-in-the-direction-of-the-mouse/12211)

<div class="topic-metadata">

**Author:** [@marcholman23](https://discourse.processing.org/u/marcholman23)\
**Replies:** 2\
**Last updated:** [June 20, 2019, 5:33pm UTC](https://discourse.processing.org/t/rotating-an-image-in-the-direction-of-the-mouse/12211 "2019-06-20T17:33:37Z")

</div>

Hi, I would greatly appreciate it if somebody could correct my code. I want to maintain object orientation. The program is intended simply to rotate a car image in the direction of the mouse. class Car { PVector l…

---

## [Unique icon while exporting signed pakage\[Android\]](https://discourse.processing.org/t/unique-icon-while-exporting-signed-pakage-android/5915)

<div class="topic-metadata">

**Author:** [@manhnt](https://discourse.processing.org/u/manhnt)\
**Replies:** 18\
**Last updated:** [June 20, 2019, 3:44pm UTC](https://discourse.processing.org/t/unique-icon-while-exporting-signed-pakage-android/5915 "2019-06-20T15:44:35Z")

</div>

I got this error while exporting my package:\[Image below\] I know this error but don’t know how to solve it. Please tell me step-by-step how to do this!:no\_mouth::thinking::thinking:

---

## [Real newb having a NullPointerException. Help wanted](https://discourse.processing.org/t/real-newb-having-a-nullpointerexception-help-wanted/12206)

<div class="topic-metadata">

**Author:** [@MNeumann](https://discourse.processing.org/u/MNeumann)\
**Replies:** 1\
**Last updated:** [June 20, 2019, 3:26pm UTC](https://discourse.processing.org/t/real-newb-having-a-nullpointerexception-help-wanted/12206 "2019-06-20T15:26:45Z")

</div>

As the title suggests, I’m real new to Processing (read: Two weeks in), and I’m having a NullPointerException when trying to do make a maze game for a final project. The issue is occuring on line 216 if(potentialxpos \> …

---

## [Receiving MIDI from Ableton but can't visualise it](https://discourse.processing.org/t/receiving-midi-from-ableton-but-cant-visualise-it/12204)

<div class="topic-metadata">

**Author:** [@Michalis](https://discourse.processing.org/u/Michalis)\
**Replies:** 0\
**Last updated:** [June 20, 2019, 2:30pm UTC](https://discourse.processing.org/t/receiving-midi-from-ableton-but-cant-visualise-it/12204 "2019-06-20T14:30:47Z")

</div>

Hello, I’m having trouble using the MIDI data I receive using The MidiBus. The problem is that I can’t use the data I receive; in example to create a shape. All I’m getting is a square displayed only 1 time and that’s a…

---

## [Input Field and Button not working in android mobile](https://discourse.processing.org/t/input-field-and-button-not-working-in-android-mobile/12203)

<div class="topic-metadata">

**Author:** [@Kabir](https://discourse.processing.org/u/Kabir)\
**Replies:** 0\
**Last updated:** [June 20, 2019, 2:00pm UTC](https://discourse.processing.org/t/input-field-and-button-not-working-in-android-mobile/12203 "2019-06-20T14:00:59Z")

</div>

I made a github page of my p5.js sketches. Some of my programs required text input from the user. So I used createInput() and createButton() function like in this one https://road-coders.github.io/Factorial/index.html. I…

---

## [GSOC 2019: pyp5js - Enable Python3 with p5.js](https://discourse.processing.org/t/gsoc-2019-pyp5js-enable-python3-with-p5-js/11465)

<div class="topic-metadata">

**Author:** [@berin](https://discourse.processing.org/u/berin)\
**Replies:** 4\
**Last updated:** [June 20, 2019, 1:50pm UTC](https://discourse.processing.org/t/gsoc-2019-pyp5js-enable-python3-with-p5-js/11465 "2019-06-20T13:50:16Z")

</div>

Hello from Brazil! Me and Alexandre Villares have been talking for a while about how we could use Python 3 with Processing. Unfortunately, it seems we’re in a dead end when it comes to Processing.py supporting Python 3 …

---

## [How can i move the right rectangle using the up and down keys](https://discourse.processing.org/t/how-can-i-move-the-right-rectangle-using-the-up-and-down-keys/12201)

<div class="topic-metadata">

**Author:** [@joey\_2002](https://discourse.processing.org/u/joey_2002)\
**Replies:** 1\
**Last updated:** [June 20, 2019, 12:12pm UTC](https://discourse.processing.org/t/how-can-i-move-the-right-rectangle-using-the-up-and-down-keys/12201 "2019-06-20T12:12:37Z")

</div>

i’ve started like two days ago and i cant figure out how top move things using the keys. this is what i got so far a bit messy but it works. int x = 320; int y = 240; int dx = +10; int dy = -5; int rx = 600; int …

---

## [Set a path to different data folder](https://discourse.processing.org/t/set-a-path-to-different-data-folder/12021)

<div class="topic-metadata">

**Author:** [@OptOut](https://discourse.processing.org/u/OptOut)\
**Replies:** 3\
**Last updated:** [June 20, 2019, 10:20am UTC](https://discourse.processing.org/t/set-a-path-to-different-data-folder/12021 "2019-06-20T10:20:49Z")

</div>

Hi everybody, I have two different sets of images that I need to keep separate. I have one set of images in the regular data folder. I am selecting these images by putting them in an array PImage\[\] images = new PImage\[…

---

## [Calling selectFolder() using Thread()](https://discourse.processing.org/t/calling-selectfolder-using-thread/12177)

<div class="topic-metadata">

**Author:** [@tribblesontoast](https://discourse.processing.org/u/tribblesontoast)\
**Replies:** 5\
**Last updated:** [June 20, 2019, 1:37am UTC](https://discourse.processing.org/t/calling-selectfolder-using-thread/12177 "2019-06-20T01:37:34Z")

</div>

Hi, I’m getting data (approx 200,000 data points) I have generated from a text file, when the selectFolder method fires the callback and runs my method to process it, the program is of course locked into this course of …

---

## [Is this a bug, if statement validation Djikstra](https://discourse.processing.org/t/is-this-a-bug-if-statement-validation-djikstra/12184)

<div class="topic-metadata">

**Author:** [@paulgoux](https://discourse.processing.org/u/paulgoux)\
**Replies:** 7\
**Last updated:** [June 19, 2019, 9:21pm UTC](https://discourse.processing.org/t/is-this-a-bug-if-statement-validation-djikstra/12184 "2019-06-19T21:21:40Z")

</div>

I’m coding a djiktsra search algorithm however I wanted to improve the last bit my programs algorithm and again run into some if statement issues, not sure if this is a bug or not. https://editor.p5js.org/paulgoux/sketc…

---

## [Serial cannot be resolved to a type](https://discourse.processing.org/t/serial-cannot-be-resolved-to-a-type/12167)

<div class="topic-metadata">

**Author:** [@VernH](https://discourse.processing.org/u/VernH)\
**Replies:** 3\
**Last updated:** [June 19, 2019, 6:10pm UTC](https://discourse.processing.org/t/serial-cannot-be-resolved-to-a-type/12167 "2019-06-19T18:10:40Z")

</div>

I have a program that uses processing to communicate with and Arduino. I have downlaoaded Processing and installed core 3.5.3 (and all other jars) into eclipse on Windows 8.1. I have import processing.serial.\* but then w…

---

## [Moving a Vehicle](https://discourse.processing.org/t/moving-a-vehicle/12107)

<div class="topic-metadata">

**Author:** [@marcholman23](https://discourse.processing.org/u/marcholman23)\
**Replies:** 7\
**Last updated:** [June 19, 2019, 4:26pm UTC](https://discourse.processing.org/t/moving-a-vehicle/12107 "2019-06-19T16:26:15Z")

</div>

Hi, I’m trying to create a program that allows the user to move a car with the up down right and left arrow keys. I want the up and down keys to accelerate backwards and forwards. I want the left and right keys to con…

---

## [Avoid 'clunky' sketch/framerate](https://discourse.processing.org/t/avoid-clunky-sketch-framerate/12041)

<div class="topic-metadata">

**Author:** [@OptOut](https://discourse.processing.org/u/OptOut)\
**Replies:** 24\
**Last updated:** [June 19, 2019, 4:10pm UTC](https://discourse.processing.org/t/avoid-clunky-sketch-framerate/12041 "2019-06-19T16:10:42Z")

</div>

Hi everybody, I am currently working on a project where I have an image wall 5 x 5 grid. The project selects and display random images from data folder after each iteration. I have hacked together a working demo over t…

---

## [Hover color change](https://discourse.processing.org/t/hover-color-change/12169)

<div class="topic-metadata">

**Author:** [@srishtiverma](https://discourse.processing.org/u/srishtiverma)\
**Replies:** 3\
**Last updated:** [June 19, 2019, 3:04pm UTC](https://discourse.processing.org/t/hover-color-change/12169 "2019-06-19T15:04:19Z")

</div>

Hello! I’m a Processing beginner. Trying to make (a few) circles and rectangles in the 100 pixel radius of the mouse coordinates change color (and maybe even move, once I have the color change down) It says “b cannot b…

---

## [\[REPORTED\] PMatrix3D cannot be cast to PMatrix2D](https://discourse.processing.org/t/reported-pmatrix3d-cannot-be-cast-to-pmatrix2d/7779)

<div class="topic-metadata">

**Author:** [@BennyHacker](https://discourse.processing.org/u/BennyHacker)\
**Replies:** 3\
**Last updated:** [June 18, 2019, 4:21pm UTC](https://discourse.processing.org/t/reported-pmatrix3d-cannot-be-cast-to-pmatrix2d/7779 "2019-06-18T16:21:31Z")

</div>

Hello forum I’ve run into an unexpected exception while trying to rotate a PShape in the Z axis, even though it works fine in the X and Y axis. Has anyone else gotten this problem? It only started happening after instal…

---

## [P5.js in React Native](https://discourse.processing.org/t/p5-js-in-react-native/12181)

<div class="topic-metadata">

**Author:** [@boyswan](https://discourse.processing.org/u/boyswan)\
**Replies:** 2\
**Last updated:** [June 19, 2019, 2:16pm UTC](https://discourse.processing.org/t/p5-js-in-react-native/12181 "2019-06-19T14:16:52Z")

</div>

Has anyone successfully got p5.js (instanced mode) working in React Native? I’ve stumbled across this which works, however it’s using processing.js rather than p5. The main issue I’m struggling with is p5’s browser/win…

---

## [Syphone - no JSyphon in java.library.path](https://discourse.processing.org/t/syphone-no-jsyphon-in-java-library-path/12160)

<div class="topic-metadata">

**Author:** [@DiscoErgoSum](https://discourse.processing.org/u/DiscoErgoSum)\
**Replies:** 2\
**Last updated:** [June 19, 2019, 2:12pm UTC](https://discourse.processing.org/t/syphone-no-jsyphon-in-java-library-path/12160 "2019-06-19T14:12:39Z")

</div>

Hi, I use Intellij to write my processing code. In my current project I like to use Syphone and it don’t will be work. The processing IDEA this thing works perfectly. I found some solutions but there won’t work. What I…

---

## [Save Data from Arduino to .txt with Processing](https://discourse.processing.org/t/save-data-from-arduino-to-txt-with-processing/12144)

<div class="topic-metadata">

**Author:** [@arpe](https://discourse.processing.org/u/arpe)\
**Replies:** 7\
**Last updated:** [June 19, 2019, 1:57pm UTC](https://discourse.processing.org/t/save-data-from-arduino-to-txt-with-processing/12144 "2019-06-19T13:57:13Z")

</div>

Hi, I’m trying to save my sensor data from the Arduino in a text-file with Processing. Now I really struggle with the Code for Processing. All I want is to save several data from the Arduino into .txt. With my actual Co…

---

## [ThrustMaster Joystick with Game Control Plus?](https://discourse.processing.org/t/thrustmaster-joystick-with-game-control-plus/12038)

<div class="topic-metadata">

**Author:** [@plux](https://discourse.processing.org/u/plux)\
**Replies:** 2\
**Last updated:** [June 19, 2019, 1:43pm UTC](https://discourse.processing.org/t/thrustmaster-joystick-with-game-control-plus/12038 "2019-06-19T13:43:03Z")

</div>

Hi, apologize for the very silly type of questions but I need to buy a Joystick and before I do that I need to make sure it actually works with Processing (otherwise my uni won’t buy it ). I was looking at this ThrustM…

---

## [Double to float](https://discourse.processing.org/t/double-to-float/12178)

<div class="topic-metadata">

**Author:** [@programmingNoob](https://discourse.processing.org/u/programmingNoob)\
**Replies:** 2\
**Last updated:** [June 19, 2019, 11:52am UTC](https://discourse.processing.org/t/double-to-float/12178 "2019-06-19T11:52:02Z")

</div>

I’m having issues with finding total velocity instead of having xVelocity and yVelocity. Would the correct strategy be to find the square root of the squares added, like with hypotenuses, or some other strategy? Here’s m…

[Previous page](https://discourse.processing.org/latest.md?no_subcategories=false&page=471)

[Next page](https://discourse.processing.org/latest.md?no_subcategories=false&page=473)