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
104 views

Smooth anmiation with LibGDX

I want to move a enemy from its current position toward the mouse position in LibGDX. x, y - enemy position saveX, saveY - position where my enemy need to go(or mouse position saved at specific ...
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1answer
278 views

Unity: Rolling a ball around a spherical planet with forces

I'm trying to make a game in Unity where the player character is a ball (a sphere), and the game world is a planet (a very large sphere) that the ball can roll around on. The ball can be rolled in any ...
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1answer
817 views

How to move Vector2 along angle?

These are my Vector2's that I am using for this function. public Vector2 position = new Vector2(); public Vector2 velocity = new Vector2(); public Vector2 movement = new Vector2(); public Vector2 ...
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1answer
184 views

How do I make a sprite move to another position using vectors

Ok, so far I have made the sprite move to a mouse position. But I got a question, does anyone know how to make a sprite move by itself without the use of a mouseclick from Point a to point b using ...
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1answer
185 views

Spaceship acceleration for following waypoints

I'm creating a turn based space ship strategy game with simultaneous turn resolution similar to Steam Birds. After all the orders are given, the ships run through a real time simulation where they ...
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1answer
54 views

How to rotate vector A around another vector B?

Lets say I know what is directly above a turret. I also know where the turrets gun is currently pointing. I would like to know where will the turret's gun will point if I rotate it. I suppose I could ...
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3answers
984 views

How to move an object along a vector

Let's say I got an object A and object B in a 2D game. I create a vector leading from A to B. It's name is AB. How can I make A move along the vector AB and reach B? One way I was thinking of doing ...
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1answer
735 views

View to normal calculation in GLSL

Sorry for the terrible title, but I really cant think of anything better.. Suggestions welcome. I am trying to do something like showcased in this video: http://www.youtube.com/watch?v=CaTI2d0tQME ...
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1answer
2k views

Basic Car Movement, Converting 2D Vectors to 3D problems

I'm trying to follow this guys method for steering a basic car. Link. It's the first example I can sort of get my head around and I'm trying to convert it to a working 3D version. To get some scope, ...
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1answer
501 views

Converting 3 axis vectors to a rotation matrix [closed]

I am trying to get a rotation matrix (in 3dsmax) from 3 vectors that form an axis (all 3 vectors are aligned by 90 degrees each other) Somewhere I read that I could build a rotation matrix just by ...
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1answer
121 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 ...
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1answer
121 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 ...
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2answers
302 views

Billboarding + aligning with velocity direction

I'm working on a particle system where I'm orientating the billboard using the inverted orientation matrix of my camera. This works quite well and my quad are rotated correctly towards the camera. ...
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1answer
513 views

Transform 3d viewport vector to 2d vector

I am playing around with 3d transformations and came along an issue. I have a 3d vector already within the viewport and need to transform it to a 2d vector. (let's say my screen is 10x10) Does that ...
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1answer
344 views

How to prevent 2D camera rotation if it would violate the bounds of the camera?

I'm working on a Camera class and I have a rectangle field named Bounds that determines the bounds of the camera. I have it working for zooming and moving the camera so that the camera cannot exit its ...
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1answer
733 views

How do I get the vertical angle between 2 vectors?

So I'm modding a 3D game, my goal is to place a label on the screen pointing to the unit's direction. I'm getting the horizontal angle by projecting these vectors in a plane, like this: private ...
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1answer
197 views

Mesh to world vector translation

Suppose I have a world defined in typical OpenGL coords.. then the up vector defined for this space is (0,1,0). Now, if I load a model that is defined with (0,0,1) as its up vector, what are the ...
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1answer
49 views

How to transform Unity terrain coordinates

My map creator created some terrain in Unity, but all my scripts are based on the X-Y axis. Is there an easy and smart way to transform them into Z-Y, or do I have to change all the vector variables ...
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0answers
140 views

Aligning a gameObject to position and normal of another gameObject inside Unity

So I am instantiating a GameObject (the one with cities and trees in the image below) and trying to align it to a hex tiles on a Sphere. So after I instantiate the gameObject, I ray-cast to get it ...
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0answers
138 views

unity3d-Find angle between 3 vector3 points obtained from swipe

I was trying to find the angle between 3 vector3 points obtained from the screen swipe. The first vector3 point is the first touch position fp, the second is some intermediate touch ip and the third, ...
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1answer
512 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 ...
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0answers
106 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 ...
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1answer
466 views

Ball bouncing at a certain angle and efficiency computations [closed]

I would like to make a pong game with a small twist (for now). Every time the ball bounces off one of the paddles i want it to be under a certain angle (between a min and a max). I simply can't ...
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0answers
324 views

Calculate initial velocity of a 3d vector-based projectile

Okay, so I got a Projectile with 2 Vectors, position and velocity. I now want to calculate the initial velocity for it in order to reach a specific point on the map. Or actually, how high has the ...
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2answers
499 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 ...
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1answer
4k views

The normal vector to a plane ax+by+cz+d=0?

I am calculating the normal vector to a plane ax+by+cz+d=0 According to the book: The normal vector N is often normalized to unit length because in that case the equation d = N ⋅Q + D gives the ...
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3answers
3k views

Scale a normalized 2D vector always to the same length

For any normalized 2D vector, except for ( 0, 0 ), how would I scale the vector to always be the same length? For example: int length = 10; vector v = vector( 0.1, 0.5 ); vector v2 = vector( 0.3, ...
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2answers
726 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 = ...
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2answers
163 views

How do I make a vector exactly reach a line?

Let's say a vector starts at Point P and points in the direction of v. How do I make sure that this vector exactly reaches the line? Its end should be exactly on the line, and not cross it.
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1answer
513 views

Vector reflect problem

I'm testing some vector reflection and I want to check what happens when a ball collides with a paddle. So if I have: Vector2 velocity = new Vector2(-5, 2); position_ball += velocity; if ...
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1answer
984 views

Determining and culling non-visible vertices

Ahoy! After posting my previous question on tile maps, i've been tinkering with an implementation i'm rather pleased with so far but would like to gather some more information about submitting ...
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2answers
154 views

Explaining vector math for a pendulum camera

I came across a code that I guess is doing a pendulum camera, that's the class name. I would like to know the math behind that. I would like also to know how to decipher those stuff in game math, ...
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3answers
115 views

How can I calculate force and acceleration?

I have problem of calculating the movement of the object. At the moment, I have a vectors calculated from the center of the screen minus the position of the object. direction vector = centerScreen ...
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2answers
441 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 ...
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3answers
1k views

Lerp vs Vector math: one better than the other?

In Unity3D (all versions, I believe), there is a static function for the Vector3D class called "lerp". It interpolates a point between two points a point, based off a provided percentage related to ...
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1answer
163 views

Vector2's static methods and the garbage collector

I discovered that Vector2's static methods return a different Vector2 from the parameters you give them and I'm under the impression that creating new objects and dereferencing old ones on this kind ...
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2answers
1k views

Calculating angle between two vectors to steer towards a target

I have been trying to implement a path following steering behaviour for AI in a 2D racing game. I have two vectors: futurePosition represents the predicted future position given the car's current ...
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1answer
47 views

What does it mean to cross a scalar with a vector in a 2D plane?

At the moment, I'm following this page to create a physics engine. As per that page, I need to cross angular velocity by a distance vector to get relative torque and such, but I'm not sure how (in a ...
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2answers
806 views

Rotate point by a direction vector

Given a vector, A, which represents a point, and a unit vector, B, which represents the looking direction, how would I rotate A so that B is the axis that's looked down on? Let's say the looking-axis ...
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1answer
56 views

Calculate slope for linear interpolated movement

I want to move rectangles to their targets the "smooth" way with linear interpolation. I hope this is right. float slope(float x1, float x2, float y1, float y2) { return std::abs((y2 - y1)) / ...
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1answer
30 views

Determining if a Point3D passed another

I have 2 points A and B in 3D space (say of type Point3D). B needs to travel towards A and then stop either when it reached or passed B. The direction between the two points is known (can be easily ...
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1answer
134 views

How do I find the angle between two 3D angles represented in this form?

I have two 3D angles, represented by [a1,a2] [a1,a2] where the a2 is < 180. My coordinates are represented as [X,Y,Z], where X,Y,Z are 64 bit ints (longs in my lang). My direction angles are ...
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1answer
137 views

What is wrong with my specular phong shading

I'm sorry if this should be placed on stackoverflow instead however seeing as this is graphics related I was hoping you guys could help me: I'm attempting to write a phong shader and currently working ...
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2answers
320 views

Using a vector to store multiple instances of a class

To warm up with SMFL, I am creating a simple Block Breaker game. For the blocks and balls, I would like to store them as "instances" in a vector so that they can be added/removed with ease. However, ...
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1answer
122 views

Creating a textured object infront of the current character in unity 3d

I've spent about half a day trying to get my head round this and i'm not having too much luck, essentially what I want to do is play an animation and then once the animation has finished create a flat ...
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1answer
81 views

How to modify normal vectors with a tranformation matrix

Transformation is quite simple when it comes to Position or Color of the vertex, for Position just multiply matrix * vector and for color just don't do anything, but my question now is: How to handle ...
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1answer
266 views

Circle-Rectangle collision velocity adjustment

I created my circle vs. rectangle method based on this algorithm: http://stackoverflow.com/questions/401847/circle-rectangle-collision-detection-intersection Currently, I have a dynamic ball with ...
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1answer
120 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 ...
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2answers
234 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 ...
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3answers
194 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 ...