Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
circle algorithm question
#1
Let's say I have a circle. The center has (x, y) coordinates (0, 0).

How do I determine the (x, y) coordinates of n points around the circumference of the circle spaced equally apart (along the circumference), assuming we start at a point (0, r), r being the radius?

Thanks....
Peace cannot be obtained without war. Why? If there is already peace, it is unnecessary for war. If there is no peace, there is already war."

Visit www.neobasic.net to see rubbish in all its finest.
Reply
#2
Like this?

Code:
#define PI 3.141592

dim as double radians
dim as integer cx, cy, r, numPoints, px, py

screen 14

cx=150
cy=120
r=100
numPoints=10

for radians=0 to PI*2 step PI*2/numPoints
    px=cx+cos(radians)*r
    py=cy-sin(radians)*r
    pset(px,py)
    'or save coordinates here
    'subtract cx and cy from px and py respectively to get
    'coordinates relatively from (0, 0)
next radians

sleep
url=http://www.copy-pasta.com]CopyPasta[/url] - FilePasta
Reply
#3
This (basically the same as Zap's heheh)?

Code:
#define PI 3.141592

dim as double radians
dim as integer angle, r, px, py

screenres 640, 480

angle = 30
r=100
numPoints=10

Do
    
    radians = angle * 3.14/180

    px = r * cos(radians)
    py = r * sin(radians)
    
    Line (320, 240)-(320 + px, 240 + py)
    
    Print PX, PY
    
    Angle += 30
    
Loop until angle > 360
sleep
Reply
#4
Thanks guys!

I needed this for a custom scenario in a Microsoft game called Rise of Legends, btw.
Peace cannot be obtained without war. Why? If there is already peace, it is unnecessary for war. If there is no peace, there is already war."

Visit www.neobasic.net to see rubbish in all its finest.
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)