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[kamac]

Hey. I am trying to draw a rounded rect. so i have to drive four halfs of circle, in correct corners.

First, i am drawing a basic circle using
r*cos(n) for x
r*sin(n) for y

So, i have a loop. ( C++ )

Code:

for(float n=0.0;n<3.0;n += 0.1)
{
sf::Shape p = sf::Shape::Line(
sf::Vector2f(dist*cos(n)+x+dist-1,dist*sin(n)+y+dist-1),
sf::Vector2f(dist*cos(n+1)+x+dist-1,dist*sin(n+1)+y+dist-1),1.0f,
sf::Color(0,0,0));
App.Draw(p);
}

Where dist = 10.

Any ideas how to draw only 1/4 of the circle? (Currently the upper-left one)

[Claw]

You're currently looping from 0.0 to 3.0, if that renders a full circle try going from 0.0 to 0.75 for a quarter.

[kamac]

Ouch. By the way, sorry wrong category. Should be technical.

You're currently looping from 0.0 to 3.0, if that renders a full circle try going from 0.0 to 0.75 for a quarter.

I'll try.

[Claw]

I'm sort of guessing, I didn't run through the maths but generally a circle will be drawn in segments, so as long as those segments are being created in sequence (ie. not skipping and coming back to them later or something weird) then it should be that simple

[Noah!]

Aw man, and I was so excited to meet up with you guys and draw circle segments...

Anyway, the way I would do it is by making a polygon and filling in the points from there, like this: (apologies, untested code!)

Code:

sf::Shape p;
p.AddPoint(x,y); // center point is important!
for (float n = 0.0; n < 1.57; n += 0.1) {
p.AddPoint(x + (cos(n) * dist), y + (sin(n) * dist));
}
App.Draw(p);

This way, you can build the shape once, and then all subsequent actions can be performed on just the one object!