Cover
 This is the archive Discourse for the Processing (ALPHA) software. Please visit the new Processing forum for current information.
 Processing 1.0 _ALPHA_    Programming Questions & Help    Programs (Moderators: fry, REAS)    Some Trig Help « Previous topic | Next topic »

 Pages: 1
 Author Topic: Some Trig Help  (Read 2162 times)
dlarrivee

 Some Trig Help « on: Apr 17th, 2005, 5:01pm »

I have a circle that I would like to draw a line from the center of, and make it go out to the edge of the circle, I'd like to be able to draw this line on all 360 degrees, but I'm not sure what to do, maybe someone who is good with trig and can viualize these things can help, here's what I have so far:

Code:
 int x, y, diam, rad; int edgex, edgey; int centerx, centery;   void setup() {   size(500, 500);   diam = 400;   rad = diam/2;   centerx = width/2;   centery = width/2;   x = centerx - rad;   y = centery - rad;   background(255); }   void loop() {   edgex = centerx;   edgey = centery - rad;       stroke(0);   ellipse(x, y, diam, diam);   stroke(255, 0, 0);   line(centerx, centery, edgex, edgey);   stroke(0);   //ellipse(x + 150/2, y + 150/2, diam - 150, diam - 150); }
alankilian

 Re: Some Trig Help « Reply #1 on: Apr 17th, 2005, 7:02pm »

I don't know anything about Java's trig routines, but here is something to get you started.

Make a variable "angle" that will count from 0 to 359
draw from (centerx,contery) to (edgex,edgey)
increment the variable angle by 45, 5, or 1 degrees.
loop.

Now, you will need to figure out of Java's sin and cos routines take a value of degrees or radians.

that you have sin(angle/(2*PI)) etc.

Let us know how it works out for you.
 « Last Edit: Apr 17th, 2005, 7:03pm by alankilian »
fry

 Re: Some Trig Help « Reply #2 on: Apr 17th, 2005, 9:47pm »

actually if you want to convert from degrees, just use:

mflux

 Re: Some Trig Help « Reply #3 on: Apr 17th, 2005, 10:30pm »

Code:

Hey Ben.
Correction: Isn't edgey supposed to be

since screen units of y counts downwards?
fry

 Re: Some Trig Help « Reply #4 on: Apr 18th, 2005, 1:55am »

oh, could be.. i was only commenting on the radians() stuff.. didn't look at the code closely.
dlarrivee

 Re: Some Trig Help « Reply #5 on: Apr 18th, 2005, 3:47am »

Wow, thanks alot. That works quite well!
 Pages: 1

 Forum Jump: ----------------------------- Discussion -----------------------------  - Community, Collaboration, Status   - Events, Publications, Propaganda   - General Processing Discussion ----------------------------- Programming Questions & Help -----------------------------  - Syntax => Programs   - Integration ----------------------------- Topics & Contributions -----------------------------  - Tools   - Responsive Form, Games   - Information Visualization   - Simulation, Artificial Life   - Tangible Computing   - Automated Systems   - Sound   - Video, Camera   - Beyond Categories ----------------------------- Suggestions -----------------------------  - Software Suggestions   - Website, Reference, Example Suggestions ----------------------------- Bugs -----------------------------  - Software Bugs   - Website, Reference, Example Bugs   - Bug Fixes, Implemented Suggestions ----------------------------- Teaching -----------------------------  - Course Blueprints   - Theory and Practice « Previous topic | Next topic »