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
31 views

Given a rotated transform, get normalized (proper up, front) version

I am working on a game where you roll a wheel down the track. Now I am looking to implement a feature, where you could turn it left and right, but I cannot get the proper vectors through which to ...
2
votes
1answer
220 views

Problems with Raycasting Requirements

Im working on a script which kinda works like an Enemy AI. Its kinda like a detection system with requirements that are required to be met. This is a recent question i asked using my code Raycast ...
3
votes
4answers
82 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
vote
1answer
69 views

Rotating a 4D matrix about the Y axis with an X-Z vector

I should mention that I'm pretty new to Matrices and will probably need a layman's answer to my question. I have a 4D matrix which represents the rotation of an object in 3D space. I have a ...
1
vote
1answer
31 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
1answer
355 views

Controlling roll rotation when travelling along bezier curves

I am currently working on a curve implementation for use in Unity which includes an editor: The aim is to get an object to follow the path represented by the curve at a constant velocity. Currently ...
3
votes
2answers
89 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 ...
2
votes
1answer
60 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 ...
3
votes
2answers
1k views

Spritekit - gradually apply force vector in different direction (space ship turning)

I have a space ship that I'm applying a force vector to using a joystick for control. I would like this to smoothly fly around when I'm switching directions.. Exactly like minisquadron if you've ...
0
votes
3answers
161 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 ...
-2
votes
1answer
16 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
votes
0answers
37 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() { ...
0
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 ...
1
vote
2answers
913 views

Detecting walls or floors in pygame

I am trying to make bullets bounce of walls, but I can't figure out how to correctly do the collision detection. What I am currently doing is iterating through all the solid blocks and if the bullet ...
5
votes
2answers
5k views

How do I use the dot product to get an angle between two vectors?

I am learning to use normalized vectors in my games. I've learned that in order to know the angle between two vectors, I can use the dot product. This gives me a value between -1 and 1, where 1 ...
1
vote
2answers
26 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
63 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
votes
1answer
60 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, ...
3
votes
2answers
126 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 ...
0
votes
1answer
125 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
votes
1answer
102 views

Would Raycast suffice for a game clock based on sun position?

I need help with some logic in my script. I created a dynamic day/night cycle that works fine in itself, but I want to add a game clock that works off the initial position of the sun (Directional ...
1
vote
1answer
72 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 ...
0
votes
2answers
32 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 ...
9
votes
2answers
4k views

How do I determine if one polygon completely contains another?

I have 2 polygons. I know the vertex coordinates of both polygons. What's the best way to check if one is completely inside the other? For example, the algorithm should only recognize the black ...
0
votes
2answers
61 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 ...
0
votes
3answers
45 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 ...
0
votes
1answer
42 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 ...
-1
votes
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
122 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 ...
0
votes
2answers
39 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, ...
-1
votes
2answers
1k views

How does atan2 work when getting angle of a vector?

I know that atan2 gives me the absolute angle of any vector. But it doesn't give a value from 0 to 360 degrees. Instead, it gives a value (if I'm not mistaken), between 0 and 180, or between 0 and ...
0
votes
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 ...
0
votes
2answers
74 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 ...
1
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0answers
67 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 ...
1
vote
0answers
24 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 ...
3
votes
2answers
427 views

calculating torque from angular momentum considering inertia moment

so I am trying to determine exactly how much torque to apply to a 3d model to make it rotate at a particular rate. I apply force from the location of each engine on the craft so if one breaks the ...
6
votes
2answers
183 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 ...
1
vote
1answer
47 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 ...
0
votes
2answers
62 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 - ...
8
votes
2answers
4k views

How do I calculate collision response between a sphere and a plane?

I'm trying to create a simple 3D game and need to constrain the player within the limits of the game world. When the player hits the sides of the world I want the player's ship to bounce off slightly. ...
1
vote
1answer
46 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 ...
-2
votes
1answer
46 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 ...
2
votes
2answers
3k views

How can I find the perpendicular to a 2D vector?

I'm making a top down game where the player moves forwards towards the position of the mouse cursor. As part of the player's movement code, I need to determine a vector that is perpendicular to the ...
2
votes
1answer
89 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 ...
0
votes
0answers
62 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
42 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. ...
1
vote
1answer
77 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 ...
4
votes
2answers
178 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
82 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
101 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, ...