line-rectangle collision detection

Question

I have one line (two point (x,y) (x1,y1)) and a rectangle with focus point (rx,ry). I need help to find out collision point between line and rectangle, an example in C++ will be help.

Answer 1

I don't see how you can represent a rectangle with just a "focus point". You'll need either the two corner points or one corner point with a width/height/rotation set of data.

However, once you have a rectangle, I would simply break it down into four lines and do the intercept checks between each of those four lines and the line you want to check against.

Doing a search on SO for "line intersection" turns up numerous questions, including this one, which seems promising. In fact, searching for "line rectangle intersection" gives you this one, which seems to be exactly what you're after.