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Circle line-segment collision detection algorithm?
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(x - h)2 + (y - k)2 = r2
(h,k) = center of circle.
Note: We've simplified the problem to 2D here, the solution we get applies also in 3D
to get:
Expand
x2 - 2xh + h2 + y2 - 2yk + k2 - r2 = 0
Plug
x = ex + tdx
y = ey + tdy
( ex + tdx )2 - 2( ex + tdx )h + h2 +
( ey + tdy )2 - 2( ey + tdy ...
jquery save json data object in cookie
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Now there is already no need to use JSON.stringify explicitly. Just execute this line of code
$.cookie.json = true;
After that you can save any object in cookie, which will be automatically converted to JSON and back from ...
ruby send method passing multiple parameters
...method-name clashes”
Black also suggests wrapping calls to __send__ in if respond_to?(method_name).
if r.respond_to?(method_name)
puts r.__send__(method_name)
else
puts "#{r.to_s} doesn't respond to #{method_name}"
end
Ref: Black, David A. The well-grounded Rubyist. Manning, 2009. P.1...
Does ARC support dispatch queues?
...he short answer: YES, ARC retains and releases dispatch queues.
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage them.
If your deployment target is iOS 6...
python design patterns [closed]
... The third link is dead. Tried to find mirror but couldn't, If anybody has the correct link please add
– formatkaka
Oct 27 '16 at 12:40
1
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Should a return statement be inside or outside a lock?
...ideal, but I wouldn't bend the code out of shape just to achieve it... And if the alternative is declaring a local variable (outside the lock), initializing it (inside the lock) and then returning it (outside the lock), then I'd say that a simple "return foo" inside the lock is a lot simpler.
To sh...
Why return NotImplemented instead of raising NotImplementedError
...hould ask someone else to satisfy the operation. In the expression a == b, if a.__eq__(b) returns NotImplemented, then Python tries b.__eq__(a). If b knows enough to return True or False, then the expression can succeed. If it doesn't, then the runtime will fall back to the built-in behavior (which ...
What's the difference between echo, print, and print_r in PHP?
...ess the same; they are both language constructs that display strings. The differences are subtle: print has a return value of 1 so it can be used in expressions whereas echo has a void return type; echo can take multiple parameters, although such usage is rare; echo is slightly faster than print. (P...
Request Monitoring in Chrome
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I know this is an old thread but I thought I would chime in.
Chrome currently has a solution built in.
Use CTRL+SHIFT+I (or navigate to Current Page Control > Developer > Developer Tools. In the newer versions of C...
What is the most accurate way to retrieve a user's correct IP address in PHP?
...VER variables headers available for IP address retrieval. I was wondering if there is a general consensus as to how to most accurately retrieve a user's real IP address (well knowing no method is perfect) using said variables?
...