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Bouyancy Tutorial Questions

Posted: Mon Feb 11, 2013 3:46 pm
by mortl66
Hello, I wanted to say first that your tutorials are really great. They help me with my Physics course.

I just have a few questions about the code, specifically, the values you use to set the objects in the code?

for example like :

Code: Select all

b2FixtureDef fd;
    fd.friction = 2.000000029802322e-01f;
    fd.restitution = 0.000000000000000e+00f;
    fd.density = 1.000000000000000e+00f;
    fd.isSensor = bool(0);
    fd.filter.categoryBits = uint16(1);
    fd.filter.maskBits = uint16(65535);
    fd.filter.groupIndex = int16(0);
    b2PolygonShape shape;
    b2Vec2 vs[8];
    vs[0].Set(2.000000000000000e+01f, -5.000000000000000e-01f);
    vs[1].Set(2.000000000000000e+01f, 5.000000000000000e-01f);
    vs[2].Set(-5.485061645507812e+01f, 5.000000000000000e-01f);
    vs[3].Set(-5.485061645507812e+01f, -5.000000000000000e-01f);
    shape.Set(vs, 4);

    fd.shape = &shape;

    bodies[1]->CreateFixture(&fd);
Also I haven't seen such notation for setting a bool.

Anyway thanks for the tutorials! Keep up the great work ^_^

Re: Bouyancy Tutorial Questions

Posted: Mon Feb 11, 2013 11:15 pm
by iforce2d
Is this from the .cpp file that gets included? As it says at the top of the file, that is generated from the RUBE editor. The actual source code used to make this 'dump' is just the b2World::Dump function that you can find in the Box2D source. It tries to output the values with as much precision as possible so that the scene can be reproduced without changes. About the bool(0) type setting, yeah, I had not seen that before either :)

Re: Bouyancy Tutorial Questions

Posted: Sun Feb 17, 2013 5:45 am
by mortl66
Yes it is and oh okay that make's sense ^_^. Thanks