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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2answers
259 views

What is the camera direction vector for an isometric view?

What values correspond to a 3D vector for screen-normal from within an isometric game? It needs to be in game coordinates. It is a standard isometric where tiles are rotated 45 degrees and half ...
0
votes
0answers
190 views

Finding a normal vector

I'm trying to replace my old integer based movement and collision system with a vector system, because its more precise and more flexible. I want to implement wall sliding, such that if a player hits ...
1
vote
2answers
127 views

Twitchy sprite movement

I'm having an issue with sprite movement, and I'm not sure how to deal with it. When I set a destination for my player sprite (by clicking the screen), it sets the player moving in that direction. ...
3
votes
1answer
105 views

How to calculate where specular highlights converge with an anisotropic shader?

If you look at a rendering with an anisotropic shader applied you will notice that there are special spots on the 3D surface/mesh where the lights seems to converge, a point where a given vector ...
1
vote
1answer
118 views

Explaining vector problem

I'm trying to simulate a centipede game, and I'm doing the snake movement. I have seen that piece of code, but can't get it, I know it gets the different between the current, previou's nodes ...
14
votes
5answers
704 views

Can I simplify the inequality “distance(p1, p2) < distance(p1, p3)?”

I am working on some vector logic, so am asking: can I save processor time by simplifying this inequality: distance(vector1, vector2) < distance(vector1, vector3) I see that vector1 is repeated ...
0
votes
0answers
28 views

Move object forward based on it's direction(1D rotation) [duplicate]

I have 2D game where I want my object to move forward based on it's direction. This is what I've tried: position.x+=Math.Cos(rotation)*speed; position.y+=Math.Sin(rotation)*speed; However this ...
2
votes
1answer
216 views

How to correctly represent a bone system?

I'm currently representing my bone system as follows, in pseudocode: root = {} root.rot = v3(0,0,0) root.pos = v3(0,0,0) function create_child(parent,rot,length): child_bone = {} ...
0
votes
0answers
189 views

Space Strategy Ship Movement Math

This is similar to a question I asked a while ago, but I phrased it so terribly so might as well start over. I am trying to implement ship movement in 3D space, but confined to a 2D plane at y=0 (see ...
0
votes
2answers
205 views

How do I calculate speed given two xy vectors?

I have some code that returns the x and y linear velocities of a moving space ship. How can I combine these to give me total speed? x = self.player._box2dBody.GetLinearVelocity().x; y = ...
1
vote
1answer
172 views

How to simulate acceleration and then deceleration?

Currently I am only using deceleration. Here is how I do it I need to cover Vector(x,y) unit distance to reach B from A. I simply do - rendering loop-> position = A + Vector(x,y).scale(factor); ...
0
votes
1answer
97 views

2D vector to Quaternion

I have a 2D vector (with only X and Y), and my engine only supports orientation through Quaternions. How do I translate a 2D vector to a quaternion? The X and Y represent the direction (so X = 0 ...
2
votes
2answers
646 views

How to find the entity I'm looking at?

I am currently making a mod for Minecraft but I have come to a stop because I am lacking in some knowledge. I need to get data for the entity I am looking at, which I believe requires the use vectors, ...
-2
votes
1answer
84 views

2D Vector Compass Direction [duplicate]

Relating to this question; What's the best way of translating a 2D vector into the closest 8-way compass direction? My query is if this would work in the following order(below) and if so, how ...
3
votes
1answer
137 views

Moving sprite from one vector to the other

I'm developing a game where enemy can shoot bullets towards the player. I'm using 2 vector that is normalized later to determine where the bullets will go. Here is the code where enemy shoots: ...
5
votes
1answer
139 views

Vector Math question

Suppose I have two game object located at two Vector3s v1 and v2, respectively. If I wanted to locate a position between v1 ad v2, but 3 units away from v2, how would I manage that in terms of ...
1
vote
1answer
213 views

Calculating projectile velocity from moving object

I'm working on a top down space shooter and am having trouble with calculating/understanding the physics for projectiles launched from the space ship. The ships have a velocity vector and a turret ...
0
votes
2answers
133 views

Finding vectors with two points

We're are trying to get the direction of a projectile but we can't find out how For example: [1,1] will go SE [1,-1] will go NE [-1,-1] will go NW and [-1,1] will go SW we need an equation of ...
1
vote
1answer
172 views

When to use an Array vs When to use a Vector, when dealing with GameObjects?

I understand that from other answers, Arrays and Vectors are the best choices. Many on SE claim that Linked Lists and Maps are bad for video game programming. I understand that for the most part, I ...
2
votes
0answers
134 views

Quaternion to direction vector - flipping

I've kinda solved this myself by adapting the Camera::setDirection code from OGRE to work for my need: Now I have the following code: Vector3 boneDir = getBoneWorldOrientation(mEntity, mHips) * ...
-1
votes
2answers
242 views

XNA Creating a directional vector from two other vectors

Could somebody please tell me what I'm missing? I have a scene where the camera is fixed in the sky looking down on a plane. On that plane is a 3D model. I want to move the 3D model in the direction ...
9
votes
4answers
856 views

How does normal mapping really work?

I'm trying to grasp the concept of normal mapping, but I'm confused by a few things. In short, I'm not sure whether a normal map is viewpoint dependent or not (i.e. whether you'll get a different ...
1
vote
2answers
449 views

Libgdx: Am I abusing Vector2? Is there a better way to do my position updates and rendering?

I'm simulating hair in a game. Currently I have a HairField object, which has a position defined by a Vector2. Each HairField has multiple Hair objects in a list, each with a position defined by a ...
0
votes
0answers
57 views

Rotation of a car? [duplicate]

I am working on a game. I want to rotate enemies car so that they face the player car and move to approach it. I tried couples of techniques and algorithm but did not get fruitful results. I want to ...
0
votes
1answer
82 views

Rotating sprites

I'm a beginner at making games, i'm currently only working in 2D using XNA. So far all of my games i've been using the following logic for sprite movement: if(left key pressed) sprite_x_position ...
1
vote
4answers
1k views

How to smoothly rotate a vector in a direction?

I'm looking for an easy way to achieve the following: Object A, B { Vector2D position; Vector2D orientation; } update(elapsed) { //rotate A's orientation in B's direction by x * elapsed ...
0
votes
1answer
192 views

Sharp DX Identity Matrix, Matrix.Forward vector pointing at negative Z

I'm trying to take a steady grip on Sharp DX. Already done some work like translating, scaling and rotating objects. Now i have to calculate the rotation matrix using only direction vector and ...
-1
votes
1answer
114 views

Optimization of Storage of Spells a Character Knows

I need to store which spells a character knows. While the game is executing I have them stored in a vector. Obviously storing this many values is either going to take a lot of computing to get the ...
8
votes
3answers
514 views

Collision detection problems using AABB's

I implemented a simple collision detection routine using AABB's between my main game sprite and various platforms (Please see code below). It works great, but I'm now introducing gravity to make my ...
-1
votes
2answers
114 views

JavaScript “Floats”, or ThreeJS wrong positioning? [closed]

I want to learn how to use Vectors with 3D. Here is a strange Error I have encountered today. Instead of stopping exactly on the other Cube, I get this: When I change the IF to (cube.position.y ...
4
votes
5answers
818 views

Implementing vector based movement in a 2d environment

Good evening. I apologize if the title is a bit vague, I really could not come up with anything better. I am currently reading a book called the nature of code and as a side project, I am working on ...
3
votes
2answers
155 views

What kind of projection is ScreenX=X/Z, ScreenY=Y/Z?

I have an existing class which transforms 3D vectors and projects them on a 2D plane (Camera). The code is all written in C without help from an external library. To project a single vector (X,Y,Z) ...
2
votes
1answer
137 views

front and back face detection

I am trying to implement a dynamic shadow system for a 2d game using this tutorial : ...
0
votes
3answers
132 views

Keeping raycast on the same level

I want my raycast to end at certain height(red line). But as the game is 3D and the camera rotates I can't use a fixed magnitude. What I thought was a stroke of genius, I figured I'd project the ...
3
votes
3answers
775 views

Tetris - Rotations using Linear Algebra (Rotation Matrices)

I'm making Tetris in Java and am at the point of rotations... Originally I was hardcoding each rotation: if (direction.equals("right")) { if (shape.equals("Bar")) { if ...
4
votes
2answers
213 views

Getting an angle in degrees from north

This may have been asked already, but I was unable to find it, because I don't really know what I'm looking for. I drew a picture: I need theta. I've seen various solutions using Vector.Dot, and ...
0
votes
2answers
283 views

Asteroids Movement

I have been making an asteroids clone, in C#. However, the ship's movement is... not quite right. My plan is this: there is a speed, and two directions, namely the direction the ship is facing ...
2
votes
2answers
406 views

Relative cam movement and momentum on arbitrary surface

I have been working on a game for quite long, think sonic classic physics in 3D or tony hawk psx, with unity3D. However I'm stuck at the most fundamental aspect of movement. The requirement is that I ...
2
votes
1answer
443 views

2D Top down acceleration vector

I have been wanting to solve the issue of movement once and for all... with all that I have learnt and read through, should be a piece of cake one would have thought... , seems it isn't. Having ...
4
votes
1answer
445 views

Why game engines usually don't offer a vector3.rotate method? [closed]

Game engines like Three.js, Ogre3d and Unity3d often don't provide a default rotate method on their vector class. You usually have to do something like: rotated = vector.applyQuaternion( new ...
7
votes
3answers
3k views

What are normal, tangent and binormal vectors and how are they used?

I would like to find out the following information: What are they? Example usage in game development (the area they are used in) About the following vector types: Normal Tangent Binormal A ...
1
vote
0answers
93 views

Rotate Points with Object in world space

I posted this in the original stack overflow then realized that a game-dev specific one exists. I am working on personal project that requires me to have 4 points surrounding an object (1 at each of ...
3
votes
3answers
802 views

Getting correct angles between Vector3s

I'm working on a project where you can draw lines between points. You select one point and drag the mouse onto another point and a line is drawn between them. The line itself is a 3d object which is ...
5
votes
1answer
247 views

Rotating plane to be parallel to given normal via change of basis

I have two planes and their respective normals. I would like to rotate the second plane, planeB, so that it is parallel to the first, planeA. To do this, I am using a change of basis to rotate each ...
2
votes
2answers
323 views

Why does handedness matter at all?

I'm really trying to understand this from a mathematical viewpoint. After all, numbers are numbers, the chirality or handedness depends on how one interprets it. Say I've three basis vectors x (1, 0, ...
0
votes
1answer
73 views

How to change Vectors due to change in it's dependent Base Vector?

PLOT : I have been developing a game where the player falls down on Y axis and the camera is a Top-Down view camera. The camera, player (main character in the game) movements etc. have all been ...
0
votes
1answer
162 views

Character movement relative to cursor position

I want my top-down shooter character to move towards the mouse when pressing the up arrow and strafe relative at right angles to it when pressing the left and right arrow keys. I can't figure out how ...
1
vote
1answer
111 views

Movement constrained to the faces of a cube

The basic setup I'm working with is a cube rendered in-Engine (Panda3d, although I only am looking for a generalized solution) as well as a 2d square on one face of the cube. The eventual outcome I'm ...
2
votes
1answer
330 views

Shooting Bullets Around a Sphere

I currently have a ship that can orbit around a sphere freely controlled by a joystick. There is a separate joystick that controls the gun and starts shooting when it is touched. Right now the ...
7
votes
7answers
1k views

What's the best way of translating a 2D vector into the closest 8-way compass direction?

If you have a 2D vector expressed as x and y, what's a good way of translating that into the closest compass direction? e.g. x:+1, y:+1 => NE x:0, y:+3 => N x:+10, y:-2 => E // closest ...