On Monday, 13 July 2015 at 16:11:03 UTC, codenstuff wrote:
I've been using Dgame framework for simple simulations.
I need moving object to be aligned to their velocity vectors.
How is it possible to do that using Dgame?
I see that shape object has setRotation and setRotationCenter.
Not sure how to use these to achieve the effect. I realize that
default is rotation around origin. This causes objects to drift
over time.
Sample code
struct GameObject {
Point **position;
// array of pointers to object points
Point *acceleration;
Point *velocity;
double max_speed;
double max_force;
}
shape = new Shape(Geometry.Quads,
Vertex(object.position[0].x, object.position[0].y),
Vertex(object.position[1].x, object.position[1].y),
Vertex(object.position[2].x, object.position[2].y),
Vertex(object.position[3].x, object.position[3].y))
// rotate shape to face velocity here
shape.move(object.velocity.x, object.velocity.y);
This is not really a game development forum but here you go:
auto rads = atan2(object.velocity.y, object.velocity.x); //
returns radians
auto degs = angle * (180.0f / PI); // convert to degrees
shape.rotate(degs);
I suggest you store velocity as a Vector2f to avoid later
confusion.
It is really useful to learn basic linear algebra, and
trigonometry as a game developer - you will be needing these
tools on a daily basis.
