SFML community forums

Help => General => Topic started by: David on May 30, 2011, 09:27:37 pm

Title: Help with collision!
Post by: David on May 30, 2011, 09:27:37 pm

I got the linkage to work, but got a little problem with the collision itself.

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       if (Collision::BoundingBoxTest(const sf::Shape& Main, const sf::Shape& Ground)){
            gravity *= -1;
        }

Gave me:

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"error: expected primary-expression before 'const'"

I'm not that good at using references, seeing that there's one there.

Title: Help with collision!
Post by: Tank on May 30, 2011, 10:04:38 pm

You're mixing a function declaration with an actual call.

Declaration:

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bool Collision::BoundingBoxTest(const sf::Shape& Main, const sf::Shape& Ground);

Call:

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Collision::BoundingBoxTest( main_shape, ground_shape );

Whereas main_shape and ground_shape are both sf::Shape objects that get automagically referenced (due to the function's signature).

Maybe start with a beginner's C++ book, it's rather basic knowledge.

Title: Help with collision!
Post by: David on May 30, 2011, 10:44:01 pm

I already tried that earlier and got this:

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error: no matching function for call to 'Collision::BoundingBoxTest(sf::Shape&, sf::Shape&)'|

Title: Help with collision!
Post by: Xander314 on May 31, 2011, 12:18:58 am

I just looked at the page for sf::Collision. It accepts two references to sf::Sprite, not two references to sf::Shape, hence the error - the compiler tells you that there is

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no matching function for call to 'Collision::BoundingBoxTest(sf::Shape&, sf::Shape&)
because there is no such function.

See here: http://www.sfml-dev.org/wiki/en/sources/simple_collision_detection

Your other code is not solving the problem, merely masking it with a more fundamental problem.

EDIT:

Quote

Maybe start with a beginner's C++ book, it's rather basic knowledge.

If you don't want to buy a book:
http://www.cplusplus.com/doc/tutorial/