A mathematical concept that can be used to express position, direction or velocity and which can simplify or outright trivialise spatial problems.

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1answer
50 views

Shooting Projectiles

I am using cocos2D-x and am trying to achieve the effect of enemies going past and shooting projectiles at the player who is moving around the screen. I am using the code below, which is based on this ...
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1answer
45 views

Simulating elastic ball collisions quickly escalates to disaster

I'm trying to learn HTML canvas and was working on a basic physical simulation, where a number of balls are drawn and set in motion, and the program simulates them colliding and bouncing off the walls ...
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1answer
54 views

Getting the Right Vector from the Forward Vector

I'm currently working on a small Camera (ArcBall) and I finally am starting to understand how it will work. I will first create a basic View Matrix using a LookAt function. Then, I will send the ...
4
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0answers
97 views

Implementing proportional navigation in 3D

Good afternoon guys, a = N * λ' * V is the formula for the commanded acceleration required to hit the target, where N is the proportionality constant, λ' is the change in line of sight and V is ...
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0answers
9 views

Correcting Vectrosity wire frame line normals

Current Setup This is my current scene, you can see that as the sphere rotates it looks like at the edges(90 degrees) to our normal you see the lines fine but dead on the almost disappear. Grid ...
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2answers
64 views

How do I handle parallel lines when looking for intersections?

I'm using the following method to determine the intersection point of two vector2: public static Vector2 LineIntersectionPoint(Vector2 startPoint1, Vector2 endPoint1, Vector2 startPoint2, Vector2 ...
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1answer
27 views

How to rotate a triangle to look at a point?

Lets say I have a triangle defined by 3 vertices and a center point, how do I rotate the triangle so its normal is looking at a specified point?
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1answer
26 views

Position of an object relative to another in a 2D plane

I have two objects, A and B, each of them has a set of coordinates (x,y). How do I understand where is A in relation to B's position? If I where to just check each coordinates I could do it like ...
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4answers
83 views

Get perpendicular vector from another vector

I should clarify that I understand there is an infinite amount of 'perpendicular' vectors in 3D space. I am creating an electricity effect, and to do this the ability to have any number of ...
0
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1answer
48 views

Convert a modified Transform.forward to world space

I am trying to make an electricity system, where it is given the start and end points and it works out a random sequence of points in the rough direction of the end point. These points are set as ...
3
votes
4answers
119 views

How to get the closest “visible” object from my “player”?

I'm using Unity 3d and i have to accomplish the following task: get the closest "visible" object to my player in forward direction. It is a sort of radar. I don't know where to start. Any advice ...
1
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1answer
36 views

Smoothing a rotation vector

I am currently using OpenCV to track the face of a person. With this I extract the feature points and calculate the objects heads pose by applying the "solvePnP" function. This function gives me a ...
3
votes
2answers
91 views

Why does transforming a Vector3 by a Quaternion result in reversed Z?

I'm trying to transform the vector (1, 0, 0) by an orientation unit quaternion, which in XNA should be: Vector3 v = Vector3.Transform(Vector3.Right, Orientation); But this results in the Z value ...
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1answer
17 views

how can i take the value of a vector 3 from a liste of vector 3 [closed]

foreach (Vector3 posit in position){ if (ang){ float a = Random.Range (0.0f, 60.0f); //Vector3 p1= new Vector3((position[i-1].x)+(ra*cos(a)),0.0f,(position[i-1].z)+(ra*Sin(a))); ...
0
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0answers
44 views

Dot product not working as expected

Recently I am learning dot product, While below code works from Unity's documentation, http://docs.unity3d.com/ScriptReference/Vector3.Dot.html public Transform other; void Update() { ...
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votes
1answer
32 views

Limit Quaternion/vector3 axe in a certain interval

I have some trouble to understand, and handle Quaternion and Vector3. I'm improving the tutorial Tank of Unity: EDIT: Because a video explain so much better, there is a link to the 30 secondes video ...
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2answers
28 views

Translating a world position to an array position

Lets keep this simple, so, assuming I have an array like this ... var array = new bool[10,10,10]; .. and then I have a start and end vector3 ... var start = new Vector3(-21,-21,-21); var end = new ...
2
votes
1answer
65 views

Should I Include the W-component of a vector when calculating it's length or dot product?

The reason I'm asking this is because I saw an implementation which did it that way but I don't quiet understand it. I mean, usually I want to get the distance between two points in 3d space and if W ...
0
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1answer
68 views

Player position not updating when referenced in seperate class?

In my player class I have my players position set to update when you tap the directional keys, that works fine, but when I access my Players position variables, in my projectile class constructor, ...
1
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1answer
81 views

How to clamp a direction vector within a direction pyramid?

In 2D you can specific an angle range such as [-45 to +45] and clamp a 2D direction vector within that angle range. I want to have something similar for 3D. I want to specify the allowed directional ...
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3answers
196 views

How to calculate the closing speed of two objects

I have the 2D positions and 2D velocity vectors of two objects. How do I calculate the closing velocity ? I want to get the closing speed. Think of one jet tracks another jet with radar and you want ...
0
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2answers
33 views

Object has its heading stored as Euler angles. After it makes a turn, how do I calculate the new angles?

Assume said object is an aircraft. I store three angles (in degrees) that describe where it's headed: yaw, pitch and roll - in that order. Let's say the plane is flying vertically, upwards. The angles ...
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2answers
64 views

How does this math behind converting angles to vectors work?

I calculated the vectors of my yaw and pitch successfully. Even tho it works fine, I can't seem to understand how the math works exactly. Could someone (graphically / demonstratively) explain me this ...
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3answers
47 views

Velocity Relative To A Vector

So I have a velocity vector b in world space and I have a "pointing" vector a in world space. I need to know how to make the velocity vector to be relative to the "pointing" vector. Better explanation ...
-1
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1answer
41 views

How do I get a vector from an angle?

I want a ship to move forward in the direction it's facing when you press the up key, but I don't know how to get a normalized vector from the angle the ship is facing. Can someone show me what code ...
0
votes
1answer
50 views

Getting vector relative to other vector in rotating object

So I have a rotating object a. It is rotating at non-constant speed around it's local x axis. It is parented to object b. When the object a rotates, it's local x axis stays facing the same direction ...
0
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1answer
149 views

How do you build a rotation matrix from a normalized vector?

I'm trying to find the correct way to build a rotation matrix from a unit vector. I have two arbitrary points in space (p1 and p2), and I'm trying to create the vertices for a rectangle to span ...
0
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2answers
42 views

Get vector3 position of Cursor on a fixed 2D plane within a 3D scene

How is it possible to get a cursors X and Y Location relative to the scene planes rather than using co-ordinates based upon pixels of screen height and width? I have the start of a very basic game, ...
0
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0answers
32 views

What Is Vector Math? [duplicate]

Okay so I was wondering, what exactly is "Vector Math"? I was wondering if I needed to know physics for game development, and most people said you just need to understand the basics, but they said ...
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0answers
77 views

Euler angles to directional vector

I wanted to implement a directional light system in my game, and instead of passing the direction to the light, I chose to use an angle, and only later convert it to a directional vector, so it is a ...
0
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2answers
79 views

Moving a ship forward from rotation

I am making a simple space simulator, where the player can control a ship using 2 controls, one for pitch and one for bank. The ship is properly rotated but I cannot figure out how to make the ship ...
3
votes
2answers
140 views

Vector math to calculate the rotation and drift of a tectonic plate?

I've been following the excellent Experilous procedural planet generation post, trying to recreate it in Java using libGDX. My planet is simpler, as it lacks any distortion of the mesh. It's just ...
1
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0answers
28 views

Movement for Box2D Bodies

I'm having trouble wrapping my head around something that should be relatively simple. I'm making a breakout clone using LibGDX and Box2D. I'm also using the Ashley ECS. For movement with bodies, I ...
1
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1answer
49 views

find Vector2 libgdx

I need to get coorinates of red point. Coordinates are just for example, it would be better to see the common formula. Found code like this, but it gains wrong result.() Vector2 o = new ...
6
votes
2answers
215 views

How to apply friction vector to acceleration in top-down 2D game?

I'm making a top-down view 2D RPG game, meaning the player can move in any direction on a 2D plane, and I'm trying to implement a somewhat realistic non-orthogonal acceleration/friction physics model ...
0
votes
2answers
69 views

How to convert velocity (Vector) to m/s (Scalar)

I have a variable called velocity which I get from a dynamic body in Box2D. It is the velocity of a pirate ship and when I add torque to the ship I want that to be proportional to the speed (m/s - ...
1
vote
1answer
56 views

Should I store local forward/right/up vector or calculate when necessary?

I'm working on an object picking and translation/rotation/scale gizmos system in my engine where you select objects and perform transformations on them in a 3d editor-like fashion (e.g. Blender) In ...
0
votes
1answer
149 views

How to rotate a triangle towards the point in Qt?

I have an issue with items rotating. I have a point and a triangle which needs to be rotated with its apex point towards the taregt point. The right side of the picture represents how it is should to ...
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votes
1answer
52 views

how to set in vector float x y coordinates [closed]

i am use eclipse java android i am try to projectile trajectory in my game like angry birds example here ...
0
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0answers
65 views

How to get the angle an object is travelling at

I'm trying to figure out how to get the angle an object is moving at, but have ran into a few problems. My player object is moved by rotating the entity left and right by using the left and right ...
1
vote
1answer
43 views

Vector out of range (Batch rendering & opengl)

So ive (tried to) implement a batch rendering system, and at the for loop the error pops up and I'm not shure what ive done wrong. Any suggestions to improve the system would be much appreciated. ...
2
votes
1answer
93 views

Ball's velocity vector, reflect against a point

I need to calculate the new velocity vector when the ball collides with one of the paddle's corners. Let d be the velocity vector of the ball, r the target velocity vector and n the surface normal ...
1
vote
1answer
86 views

How to calculate a vector for multi-axis rotations from sphere coordinates?

I'm working on a SceneKit project in iOS, trying to rotate a sphere (representing a planet) so that a point at a given longitude/latitude coordinate is facing "forward" (i.e. that point moves to the ...
2
votes
1answer
73 views

Find your value between four values in a grid based on distance, Unity

Please note: Originally posted in stack overflow, redirected due to nature of problem. I am making a procedural mesh game. I am trying to calculate the temperature for the player's current chunk by ...
4
votes
2answers
189 views

Movement with Vector Math

After reading This SO post on Vectors, I'm still pretty confused on how to use vectors to move my entities at any angle. The SO post assumes only 90 degree angles: if up pressed: direction = ...
1
vote
1answer
83 views

How to make an enemy projectile head to the player's position with constant speed

How can I dynamically set the movement speed of the X and Y of the projectile so that it moves at a constant speed when the projectile heads at the player's position? I know this has something to do ...
3
votes
4answers
114 views

Intersection of a Line and a Rectangle

I have to calculate the intersection of a line segment (represented by 2 points) with a rectangle. For example: Axis aligned rectangle corners: (0, 0) (100, 100) Point 1: (50, 50) Point 2: (50, ...
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1answer
59 views

Moving vector shooting at other moving vector

The following code creates an accurate shot to be made at a moving target from a stationary position. (ie a tower or non-moving vector). It works GREAT, but I need it to consider the movement of the ...
2
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0answers
31 views

Weird warping with per-vertex normals

I've had this little problem for a while now, where for some reason my calculations for per-vertex normals results in a weird distortion or warping, skewing my lighting, shading, and reflection ...
2
votes
1answer
66 views

How do I create a rocket projectile that is “dropped”, then accelerates toward the enemy?

I'm making an Asteroids-like game. I've successfully implemented linear bullets. Now I want to add some rocket-styled bullets, with a certain flight path: The rockets should be "dropped" back first, ...