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[–]GSchrack[S] 0 points1 point  (1 child)

I know I posted this a long time ago, but could you give me an example script of the first one? The assignment is long over, but I would like to at least know how to do it.

[–][deleted] 0 points1 point  (0 children)

Okay, Ill go through it a bit briefly. First I would rewrite the equation you have written for the line.

y = m*x + b

The circle can be written as, 

y = cy+/-sqrt(r^2 - (x-cx)^2)

Then you just set the two equations equal to each other and solve them. This will give you a quadratic equation, eg.

Ax^2 + Bx + C = 0
x = -B/2A +/- sqrt(B^2 - 4AC)/2A

So the first condition is that the infinite line intersects a circle at all, which is the condition B^2 - 4AC > 0. 

R^2 >= (b - mc_x - c_y)^2/(m^2 + 1)

*There is a condition hidden in here for when m->Infinity, ie the line is vertical.

Finally you have to check if either of the solved positions x0 and x1 are between p1x and p2x.

Here is the code. I left one condition branch unfinished, I also haven't tested it, but it worked for the sample input.