Line Segment Circle Intersection

Question

I am trying to determine the point at which a line segment intersect a circle. For example, given any point between P0 and P3 (And also assuming that you know the radius),

Answer 1

Go for this code..its save the time

private boolean circleLineIntersect(float x1, float y1, float x2, float y2, float cx, float cy, float cr ) {
      float dx = x2 - x1;
      float dy = y2 - y1;
      float a = dx * dx + dy * dy;
      float b = 2 * (dx * (x1 - cx) + dy * (y1 - cy));
      float c = cx * cx + cy * cy;
      c += x1 * x1 + y1 * y1;
      c -= 2 * (cx * x1 + cy * y1);
      c -= cr * cr;
      float bb4ac = b * b - 4 * a * c;

         // return false  No collision
         // return true Collision
      return bb4ac >= 0;
    }