# Processing

**URL:** https://discourse.processing.org/c/processing/6.md?no_subcategories=false&page=314

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

**Page:** 315

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## [Problem with movement of ball and its speed](https://discourse.processing.org/t/problem-with-movement-of-ball-and-its-speed/9229)

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**Author:** [@Michalis](https://discourse.processing.org/u/Michalis)\
**Replies:** 3\
**Last updated:** [March 16, 2019, 4:18pm UTC](https://discourse.processing.org/t/problem-with-movement-of-ball-and-its-speed/9229 "2019-03-16T16:18:09Z")

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Hello, I’m really new to Processing and programming in general so I’m having some hard time to realize my project. I’m kinda lost right now and I’d really appreciate some help. So, I’m having this code, in which I want …

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## [Help needed "the function add does not exist"](https://discourse.processing.org/t/help-needed-the-function-add-does-not-exist/9329)

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**Author:** [@Qualitykittenpainter](https://discourse.processing.org/u/Qualitykittenpainter)\
**Replies:** 3\
**Last updated:** [March 16, 2019, 11:13am UTC](https://discourse.processing.org/t/help-needed-the-function-add-does-not-exist/9329 "2019-03-16T11:13:14Z")

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Hi there, I’am trying to make a animation with animals increasing in number. But i run in to an error :frowning: i now have one animal that is increasing in number ( katten) . but i want the “paarden” to do the same. …

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## [Trigonometry help--find third point of the triangle](https://discourse.processing.org/t/trigonometry-help-find-third-point-of-the-triangle/9127)

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**Author:** [@cras](https://discourse.processing.org/u/cras)\
**Replies:** 16\
**Last updated:** [March 15, 2019, 10:35pm UTC](https://discourse.processing.org/t/trigonometry-help-find-third-point-of-the-triangle/9127 "2019-03-15T22:35:28Z")

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It’s been a few too many years since I took geometry, so I’ve been beating my head against what should be a simple problem :grimacing:. The goal, illustrated by the test sketch, is to calculate the 3rd point of a triang…

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## [Mapping an image onto a torus](https://discourse.processing.org/t/mapping-an-image-onto-a-torus/9289)

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**Author:** [@pblancos](https://discourse.processing.org/u/pblancos)\
**Replies:** 2\
**Last updated:** [March 15, 2019, 8:03pm UTC](https://discourse.processing.org/t/mapping-an-image-onto-a-torus/9289 "2019-03-15T20:03:41Z")

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I would like to create same as image in this article. Map the world onto a torus by using GLSL shader. I tried, but my sketch empty. How to do?

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## [Problem making dissapair the Space Invaders enemys](https://discourse.processing.org/t/problem-making-dissapair-the-space-invaders-enemys/9332)

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**Author:** [@wakonero](https://discourse.processing.org/u/wakonero)\
**Replies:** 1\
**Last updated:** [March 15, 2019, 7:46pm UTC](https://discourse.processing.org/t/problem-making-dissapair-the-space-invaders-enemys/9332 "2019-03-15T19:46:36Z")

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Hello there! Im making a space invaders games, but im stuck trying to make dissapear the enemys of an a Array when they collision with the bullet, because i dont know how to number every enemy in the array to disapear.…

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## [Where to place certain values in a chart code](https://discourse.processing.org/t/where-to-place-certain-values-in-a-chart-code/8749)

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**Author:** [@Floralvxins](https://discourse.processing.org/u/Floralvxins)\
**Replies:** 5\
**Last updated:** [February 27, 2019, 8:38am UTC](https://discourse.processing.org/t/where-to-place-certain-values-in-a-chart-code/8749 "2019-02-27T08:38:53Z")

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I’m having a bit of confusion on understanding just simple placement of my data. I’m making a pie chart based off of a data set so I know I have to plug them into where it says diameter and such but can someone help clar…

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## [Wrapping a sentence, around a circle, letter by letter](https://discourse.processing.org/t/wrapping-a-sentence-around-a-circle-letter-by-letter/9056)

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**Author:** [@DM\_Slippin](https://discourse.processing.org/u/DM_Slippin)\
**Replies:** 20\
**Last updated:** [March 15, 2019, 12:45am UTC](https://discourse.processing.org/t/wrapping-a-sentence-around-a-circle-letter-by-letter/9056 "2019-03-15T00:45:56Z")

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Hi there! To cut to the chase, today I’ve signed up and submitted my code to hopefully have some answers pertaining to a project I’ve been working on. For a rundown of what I was trying for, I wanted to take a quote an…

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## [Interesting(?) type coercion](https://discourse.processing.org/t/interesting-type-coercion/9248)

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**Author:** [@saintrain](https://discourse.processing.org/u/saintrain)\
**Replies:** 4\
**Last updated:** [March 14, 2019, 11:58pm UTC](https://discourse.processing.org/t/interesting-type-coercion/9248 "2019-03-14T23:58:53Z")

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Hi! Starting with int framePer = floor(1000./frameRate), bgTO = 1000; // \<- this is not interesting This is ok: int dClr = floor(255\*framePer/bgTO); // \<- expected This fails with a ‘can’t f…

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## [Example 5-7 ~ BOUNCING COLOR ~ in Dan Shiffman book](https://discourse.processing.org/t/example-5-7-bouncing-color-in-dan-shiffman-book/9309)

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**Author:** [@debxyz](https://discourse.processing.org/u/debxyz)\
**Replies:** 2\
**Last updated:** [March 14, 2019, 9:43pm UTC](https://discourse.processing.org/t/example-5-7-bouncing-color-in-dan-shiffman-book/9309 "2019-03-14T21:43:54Z")

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When I run the code below (from Shiffman, p87, example 5-7, the color gradates back and forth only once. Why doesn’t it endlessly bounce back and forth? I thought if the “if” statement included an " = \* -1" this would …

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## [Expanding circles, how do I do it?](https://discourse.processing.org/t/expanding-circles-how-do-i-do-it/9305)

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**Author:** [@fraxinus](https://discourse.processing.org/u/fraxinus)\
**Replies:** 8\
**Last updated:** [March 14, 2019, 8:05pm UTC](https://discourse.processing.org/t/expanding-circles-how-do-i-do-it/9305 "2019-03-14T20:05:26Z")

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How do I make a circle that starts as a dot and then keeps getting bigger until it disappears? Also then, how would I have more circles continuously appearing from that same point one after the other so I get what looks…

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## [How to check if an Array was defined?](https://discourse.processing.org/t/how-to-check-if-an-array-was-defined/9297)

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**Author:** [@Schred](https://discourse.processing.org/u/Schred)\
**Replies:** 2\
**Last updated:** [March 14, 2019, 4:48pm UTC](https://discourse.processing.org/t/how-to-check-if-an-array-was-defined/9297 "2019-03-14T16:48:24Z")

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Hi! So I have this String Array in my little programm called allData and it is defined by allData = saveStrings(URL);. But what if there’s no wifi connection on the device? The programm will crash instantly, because I u…

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## [Processing to Socket.Io on Unubo](https://discourse.processing.org/t/processing-to-socket-io-on-unubo/9182)

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**Author:** [@Quillbert1](https://discourse.processing.org/u/Quillbert1)\
**Replies:** 4\
**Last updated:** [March 14, 2019, 4:35pm UTC](https://discourse.processing.org/t/processing-to-socket-io-on-unubo/9182 "2019-03-14T16:35:13Z")

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Hi, I have a socket.io app hosted on a website called Unubo (paint.unubo.cloud), and when I try to connect to it using the Websockets library for processing, I get this error: onError(UpgradeException: Didn't switch pro…

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## [Threading on image processing](https://discourse.processing.org/t/threading-on-image-processing/8439)

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**Author:** [@doni](https://discourse.processing.org/u/doni)\
**Replies:** 3\
**Last updated:** [March 14, 2019, 12:45pm UTC](https://discourse.processing.org/t/threading-on-image-processing/8439 "2019-03-14T12:45:20Z")

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hi i try to add another thread to improve fps or might be rendering process but my code do not succed import processing.video.\*; Capture video; void setup() { size(640, 480); // Uses the default video input, see t…

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## [A Circle tile instead of square one](https://discourse.processing.org/t/a-circle-tile-instead-of-square-one/9140)

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**Author:** [@l3ehfar](https://discourse.processing.org/u/l3ehfar)\
**Replies:** 4\
**Last updated:** [March 14, 2019, 7:36am UTC](https://discourse.processing.org/t/a-circle-tile-instead-of-square-one/9140 "2019-03-14T07:36:30Z")

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here’s my hexagonal tiling in a square shape, I would like to convert the square shape into a circle one, can anyone help me? float unitSize = 15; float eqTriH = 0.8660254; int w = 600; int h = 600; int cellsX = int(w/(…

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## [AES - Login algorithm](https://discourse.processing.org/t/aes-login-algorithm/8951)

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**Author:** [@GWAK](https://discourse.processing.org/u/GWAK)\
**Replies:** 5\
**Last updated:** [March 14, 2019, 2:35am UTC](https://discourse.processing.org/t/aes-login-algorithm/8951 "2019-03-14T02:35:12Z")

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Hi. I want to create a login system, not a different one. How would you not have a sample code created through a security algorithm? Please help me.

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## [Need Help Understanding Code (Gravity)](https://discourse.processing.org/t/need-help-understanding-code-gravity/9217)

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**Author:** [@gaggiatoraya](https://discourse.processing.org/u/gaggiatoraya)\
**Replies:** 3\
**Last updated:** [March 13, 2019, 9:00pm UTC](https://discourse.processing.org/t/need-help-understanding-code-gravity/9217 "2019-03-13T21:00:09Z")

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I’m fairly new to processing and while attempting to code Gravity into my assignment I came across a template for coding gravity and acceleration. The problem is im not sure what the point of the last line y=height is. f…

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## [Image processing, find coordinates in an image](https://discourse.processing.org/t/image-processing-find-coordinates-in-an-image/9235)

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**Author:** [@Daniel\_Kamel](https://discourse.processing.org/u/Daniel_Kamel)\
**Replies:** 4\
**Last updated:** [March 13, 2019, 7:11pm UTC](https://discourse.processing.org/t/image-processing-find-coordinates-in-an-image/9235 "2019-03-13T19:11:22Z")

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Hello everyone, I’m new to image processing so any help would be appreciated, I have an image with 2 red lines in it(the image only contains those 2 lines with a black or white background), what method or algorithm would…

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## [Rotating an object based upon mouse position](https://discourse.processing.org/t/rotating-an-object-based-upon-mouse-position/9236)

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**Author:** [@P1505](https://discourse.processing.org/u/P1505)\
**Replies:** 3\
**Last updated:** [March 13, 2019, 9:12am UTC](https://discourse.processing.org/t/rotating-an-object-based-upon-mouse-position/9236 "2019-03-13T09:12:33Z")

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Hi all. I have a couple of questions I’m stumped on. I’m trying to make a basic dial control, where rotation outputs a +1 or -1 so I can update a number on the screen. Before I get to that though I’m struggling with the…

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## [If two objects touch](https://discourse.processing.org/t/if-two-objects-touch/8876)

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**Author:** [@LordCacops](https://discourse.processing.org/u/LordCacops)\
**Replies:** 3\
**Last updated:** [March 12, 2019, 9:11pm UTC](https://discourse.processing.org/t/if-two-objects-touch/8876 "2019-03-12T21:11:51Z")

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Hello. I have objects in an array list. They are rectangular, but more complex than single rectangles. They are collections of rectangles. I want something to happen if two of these “Animal” objects touch. If these were…

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## [Check direction for a object](https://discourse.processing.org/t/check-direction-for-a-object/9139)

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**Author:** [@vincentstrebelle](https://discourse.processing.org/u/vincentstrebelle)\
**Replies:** 8\
**Last updated:** [March 12, 2019, 8:39pm UTC](https://discourse.processing.org/t/check-direction-for-a-object/9139 "2019-03-12T20:39:27Z")

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Hi, i wonder how to check and know the diretions (left,right,up and down) for an object in motion. Here is the exemple from Daniel Shiffman: Vehicle v; boolean debug = true; float d = 25; void setup() { size(640, …

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## [Assistance with reformattin issue](https://discourse.processing.org/t/assistance-with-reformattin-issue/9163)

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**Author:** [@NationalRex22](https://discourse.processing.org/u/NationalRex22)\
**Replies:** 1\
**Last updated:** [March 12, 2019, 5:18pm UTC](https://discourse.processing.org/t/assistance-with-reformattin-issue/9163 "2019-03-12T17:18:43Z")

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Hello, I’m writing to request a bit of assistance related to changing fonts for a couple words. For example, what I’m trying to accomplish is switching an inline font, Palatino Lynotype, for a web page’s title (located …

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## [More GameControlPlus Woes!](https://discourse.processing.org/t/more-gamecontrolplus-woes/9020)

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**Author:** [@alan856](https://discourse.processing.org/u/alan856)\
**Replies:** 3\
**Last updated:** [March 12, 2019, 5:03pm UTC](https://discourse.processing.org/t/more-gamecontrolplus-woes/9020 "2019-03-12T17:03:35Z")

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Still trying to get the custom joystick working. Have a test test Processing script to access it but the returned data does not change. Here is the setup: Arduino Micro reading pots via Joystick library The Arduino is…

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## [Problem with keypressed](https://discourse.processing.org/t/problem-with-keypressed/9225)

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**Author:** [@yonjukyu](https://discourse.processing.org/u/yonjukyu)\
**Replies:** 2\
**Last updated:** [March 12, 2019, 4:10pm UTC](https://discourse.processing.org/t/problem-with-keypressed/9225 "2019-03-12T16:10:02Z")

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hello i want to make my “rect” moove when i press “LEFT” but with this code the rect is mooving even if nothin is pressed. (i used keyreleased because i want to press many keys at the same time) what’s wrong??: int x …

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## [loadShape() throwing error when loading svg](https://discourse.processing.org/t/loadshape-throwing-error-when-loading-svg/9223)

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**Author:** [@charly4710](https://discourse.processing.org/u/charly4710)\
**Replies:** 1\
**Last updated:** [March 12, 2019, 10:29am UTC](https://discourse.processing.org/t/loadshape-throwing-error-when-loading-svg/9223 "2019-03-12T10:29:03Z")

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Hi, I struggle with loadshape() when loading certain svg files. the files are created in icograms.com, and are perfectly readable in browsers and in inkscape. parsed: m,51.4,41.9,c,0,.1,-.1.2,-.2.1,s,-.2,-.2,-.2,-.4.1…

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## [RuntimeException](https://discourse.processing.org/t/runtimeexception/9219)

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**Author:** [@WowMG](https://discourse.processing.org/u/WowMG)\
**Replies:** 1\
**Last updated:** [March 12, 2019, 7:22am UTC](https://discourse.processing.org/t/runtimeexception/9219 "2019-03-12T07:22:06Z")

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Hi, I’m getting this error. Can anyone tell me what it means? RuntimeException: Expected a ',' or '}'

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## [Help with my homework!](https://discourse.processing.org/t/help-with-my-homework/9211)

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**Author:** [@xlotg](https://discourse.processing.org/u/xlotg)\
**Replies:** 1\
**Last updated:** [March 12, 2019, 1:56am UTC](https://discourse.processing.org/t/help-with-my-homework/9211 "2019-03-12T01:56:46Z")

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I have to create a game where “balloons” float up the screen and when you click them they disappear. I’m having trouble making them disappear on mouse press and don’t know how to do this. Keep it simple please! Balloon\[…

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## [Steering Behaviors - Obstacle Avoidance](https://discourse.processing.org/t/steering-behaviors-obstacle-avoidance/3899)

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**Author:** [@Sarah](https://discourse.processing.org/u/Sarah)\
**Replies:** 14\
**Last updated:** [March 11, 2019, 7:32pm UTC](https://discourse.processing.org/t/steering-behaviors-obstacle-avoidance/3899 "2019-03-11T19:32:02Z")

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Hi, Recently I’ve been trying to implement Craig Reynolds steering behaviors into my program, and as I’ve come up to obstacle avoidance, I’ve found it difficult to replicate his example. (Video of what I’m trying to mak…

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## [How to display German letters in Processing?](https://discourse.processing.org/t/how-to-display-german-letters-in-processing/9198)

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**Author:** [@Schred](https://discourse.processing.org/u/Schred)\
**Replies:** 2\
**Last updated:** [March 11, 2019, 5:31pm UTC](https://discourse.processing.org/t/how-to-display-german-letters-in-processing/9198 "2019-03-11T17:31:51Z")

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Hi! So I don’t know if anyone here had that problem before, but I was wondering how I could display the German letters “ö, ö, ü” in Processing. Every font that could display those letters in word could not do that in P…

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## [G4P Question - Create / hide second screen](https://discourse.processing.org/t/g4p-question-create-hide-second-screen/9132)

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**Author:** [@WyattStorch](https://discourse.processing.org/u/WyattStorch)\
**Replies:** 7\
**Last updated:** [March 11, 2019, 4:44pm UTC](https://discourse.processing.org/t/g4p-question-create-hide-second-screen/9132 "2019-03-11T16:44:59Z")

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@quark I apologize in advance for my newbiness. I’m using Processing 3.5.3, G4P V4.2.1, and GUI Builder 4.3 in Windows 7 64 bit. I love your utility but in my newbiness I’m having a devil of a time trying to figure it o…

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## [Traffic Simulation based on the Wolfram Rule 184](https://discourse.processing.org/t/traffic-simulation-based-on-the-wolfram-rule-184/9109)

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**Author:** [@RomanKot](https://discourse.processing.org/u/RomanKot)\
**Replies:** 6\
**Last updated:** [March 11, 2019, 3:12pm UTC](https://discourse.processing.org/t/traffic-simulation-based-on-the-wolfram-rule-184/9109 "2019-03-11T15:12:47Z")

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Why do we need noStroke() here? The code is based on an example from Examples library. Why can I not change the width of rect()? int\[\] cells; int generation; void setup() { size(640, 360); background(255); cells…

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