### Circle Drawing algorithm

Posted:

**January 23rd, 2013, 8:26 pm**Just going through lesson 11 on draw circle and paused it before chili implemented the full circle code.

I came up with my own code that draws a circle. I think it works by rotating the circle so there will be pixels write overlap.

Just messed around with it abit and it worked.

--Andy

I came up with my own code that draws a circle. I think it works by rotating the circle so there will be pixels write overlap.

Code: Select all

```
void D3DGraphics::DrawCircle( int cx, int cy, int rad, int r, int g, int b )
{
float radSqr = rad * rad;
for( int x = -rad; x <= rad; x++ )
{
int y = sqrt( radSqr - x*x ) + 0.5f;
PutPixel( cx + x , cy + y ,r,g,b);
PutPixel( cx + x ,(cy - y ) ,r,g,b);
PutPixel( cx + y , cy + x ,r,g,b);
PutPixel((cx - y), cy + x ,r,g,b);
}
}
```

--Andy