Question

I have two objects in a game, which for this purpose can be considered points on a 2d plane, but I use Vector3s because the game itself is 3d.

I have a game camera which I want to align perpendicularly (also on the plane) to the two objects, so that they are both in view of the camera. Due to the nature of the game, the objects could be in any imaginable configuration of positions, so the directional vector between them could have any direction.

Part1: How do I get the perpendicular angle from the two positional vectors?

I have:

Vector3 object1Position; // x and z are relevant
Vector3 object2Position;

I need:

float cameraEulerAngleY;

Part2: Now, because of the way the game’s assets are modelled, I want to only allow the camera to view within a 180 degree ‘cone’. So if the camera passes a certain point, it should use the exact opposite position the above math might produce.

An image is attached of what I need, the circles are the objects, the box is the camera.

I hope this post is clear and you guys won’t burn me alive for being total rubbish at vector math 😛

greetings,
Draknir

Answer 1

You’ll need to specify a distance from the object line, and an up vector:

Vector3 center = 0.5 * (object2position + object2position)
Vector3 vec12 = object2position - object1position

Vector3 normal = Cross(vec12, up)
normal.Normalize()
Vector3 offset = distance * normal

Vector3 cameraA = center + offset
Vector3 cameraB = center - offset
< choose which camera position you want >

Instead of using Euler angles, you should probably use something like LookAt() to orient your camera.