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Index › Programming Questions & Help › Programs › Rotate->Vertex->Rotate->Vertex...
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Rotate->Vertex->Rotate->Vertex... (Read 684 times)
tokyorose
Rotate->Vertex->Rotate->Vertex...
Mar 16th, 2007, 12:35am  
Can someone give me a hand with my first program.

I'm trying to make an N-Gon but something seems to be failing.

int winSize = 500;

void setup()
{
 size(winSize, winSize);
 stroke(102);
 smooth();
 frameRate(30);
}

void draw()
{
background(0);
stroke(127);
fill(77);
float numSides = 6.0;

translate(100,100);

 beginShape();
 for(int i = 0; i<numSides; i++)
 {
   rotate((i / numSides) * 6.28318);
   vertex(0, 10);
 }
 endShape();  
}
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eskimoblood
Re: Rotate->Vertex->Rotate->Vertex...
Reply #1 - Mar 16th, 2007, 8:22am  
As all points of your ngon lie on a circle, you have to create points with the same angle on a circle. So you have divide TWO_PI (thats 360 degree) by your sideNum and multiply by your i in the for-loop.

Quote:


int winSize = 500;

void setup()  
{
 size(winSize, winSize);
 smooth();
 stroke(127);
 fill(77);
}

void draw()  
{
 background(250);

 int numSides = 4;
 float rad=100; //the radius of your ngon
 translate(100,100);

 beginShape();
 for(int i = 0; i<numSides; i++)
 {
   float x=cos(TWO_PI/numSides*i)*rad;
   float y=sin(TWO_PI/numSides*i)*rad;
   vertex(x, y);
 }
 endShape();
}
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Andreas Köberle {eskimoblood}
222550793  
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