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1. GIDEROS BOX2D SET VELOCITY OF OBJECT MOVIE
2. GIDEROS BOX2D SET VELOCITY OF OBJECT UPDATE
3. GIDEROS BOX2D SET VELOCITY OF OBJECT CODE

Here you are configuring a rectangle that's centered at local coordinates of (0, rectangle.height) and rotated about this center by rotation radians.

GIDEROS BOX2D SET VELOCITY OF OBJECT CODE

In your code example that reads as: tAsBox(rectangle.width*0.5f, // half width Void SetAsBox(float32 hx, float32 hy, const b2Vec2& center, float32 angle) / angle the rotation of the box in local coordinates. / center the center of the box in local coordinates. In the Box2D 2.3.2 C++ sources for the polygon shape you're using, is the following documentation that goes with this method: /// Build vertices to represent an oriented box. With these understandings and definitions, recognize that the third and fourth parameters to tAsBox are relative to the transformation of the body (the body's combined translation and rotation matrices) that the shape is associated with. Let's then agree to call this origin the local origin of that body, say that it's values are also (0, 0), and recognize that this local origin is relative to the world location of the body. Thus the origin of local coordinates is effectively the world location of the body the local coordinates are relative to. Specifically they're relative to the location returned by the b2Body::GetPosition() C++ method (which is given by the positional portion of the body's transformation). Local coordinates meanwhile, are coordinates that are relative to a Box2D body's location. For the sake of this answer though, lets agree to say that the world origin is at (0, 0) in the 2-D world space. But in another sense, that's just moving everything within the world over by the newOrigin amount and the origin is essentially still and always at (0, 0). In a sense, this origin can be shifted by calling the b2World::ShiftOrigin(const b2Vec2& newOrigin) C++ method. In Box2D the world origin is at location (0, 0). As cartesian coordinates, they have an origin. They're 2-D cartesian coordinate locations within an instance of a Box2D world. In Box2D 2.3.2, there is a notion of world coordinates and there is the notion of local coordinates.

GIDEROS BOX2D SET VELOCITY OF OBJECT MOVIE

To quote a line from a movie I love: "get specific Bob"! Seems like there's some confusion going on about what does what. Remember that you can't apply a force to a kinematic body but it can be translated and rotated. Kinematic bodies should be used only when necessary for an object to be manipulated through code. Static bodies are frozen and unaffected by outside physics, while dynamic bodies are affected by forces, gravity, angular momentum, etc. Kinematic bodies are the in-between of dynamic bodies and static bodies.

GIDEROS BOX2D SET VELOCITY OF OBJECT UPDATE

static! It should be very simple to update your code, just replace StaticBody with KinematicBody and then the objects should be moveable. To put it another way, kinematic bodies are very similar to static bodies, however, you can't translate, rotate, move, etc. "A kinematic body is an hybrid body which is not affected by forces and collisions like a static body but can moved with a linear velocity like a dynamic body." "A static body is a body which isn’t affected by world forces it does not react to collisions.

"A dynamic body is a body which is affected by world forces and react to collisions. Rotation * greesToRadians) // angle to radiansīodyDef.type = ī(rectangle.x, rectangle.y) // set the position Vector2(0f, rectangle.height), // new origin tAsBox(rectangle.width*0.5f, // half width My attempt : val rotation = 45f // rotation angle (in degree) How can I set the position from another origin, and rotating from this same origin ? (the upper left corner and not the center of the shape) I assume that the origin is used for the rotation, but not the position. (an offset is apply between the current position and the expected position) But then when I set the position, the body is not where it is supposed to be. Regarding the documentation, I can set origin using the setAsBox method. And origins of objects in this editor are in the left upper corner. Why ? Because I create bodies from TiledMapEditor object. I try to rotate a static body of a PolygonShape, from another origin, and set the position regarding this new origin.