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
661 views

How to rotate an object to face another in Unity?

I'm having an issue where I can't seem to rotate my bullet appropriately whenever I spawn one. I currently have a capsule prefab I am testing with. I spawn it with the following code. ...
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1answer
107 views

Averaging normals, or tangents

I am using a library to load an obj but it doest compute the tangets for each vertex, which I need for normal mapping and pom. I computed my tangets, and bitangents, everything appears to be fine, but ...
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1answer
38 views

Vector magnitude in orientation

First, a quick overview of my problem: I have a game entity which has a quaternion to represent its rotation/orientation. It also has a 3D vector in world space for its linear velocity. From the ...
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2answers
94 views

How to get the normal that points *out* of a polygon

In 2D, each vector (x, y) has two normals: (-y, x) and (y, -x), pointing in opposite directions. Say I have a polygon and for each of it's edges I need to get the normal pointing outwards. In the ...
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2answers
292 views

Adding an angle variance to a 3d vector

I am converting a particle emitter from 2d to 3d. In the 2d system the original coder used a random angle variance and added it to the angle. So it would be something like: thisAngle = emitterAngle ...
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1answer
140 views

3D vector graphics - maintaining correct Z 'length'

So I'm trying to build myself a 3D display 'engine', or whatever it ought to be called. I've been experimenting with PyGame, as it's familiar to me. In a way this has almost been more an excuse to ...
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2answers
151 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. ...
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1answer
583 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); ...
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1answer
443 views

How do I get the axes for SAT collision detection

In SAT collision detection how do I calculate the axes for projection?
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1answer
746 views

how can i get rotation vector from matrix4x4 in xna?

i want to get rotation vector from matrix to realize some parent-children system for models. Matrix bonePos = link.Bone.Transform * World; Matrix m = Matrix.CreateTranslation(link.Offset) * ...
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1answer
276 views

Viewport.Unproject - Checking if a model intersects a large sprite

Let's say I have a sprite, drawn like this: spriteBatch.Draw(levelCannons[i].texture, levelCannons[i].position, null, alpha, levelCannons[i].rotation, Vector2.Zero, scale, SpriteEffects.None, 0); ...
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1answer
2k views

Vector movement in space type game (Mouse rotation)

I'm having an issue with my movement in my 'game' prototype. It's basically not working and admittedly my knowledge with vectors is lacking. The issue I'm running into is that the ship won't move in ...
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1answer
595 views

Trouble with SAT style vector projection in C#/XNA

Simply put I'm having a hard time working out how to work with XNA's Vector2 types while maintaining spatial considerations. I'm working with separating axis theorem and trying to project vectors onto ...
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1answer
168 views

Moving in an arc using Vector3

I'm trying to get this object to move right across the screen until it gets close to the center and arc down smoothly into a straight downward movement. Here's what I've tried: if (position.X < ...
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1answer
293 views

XNA - Incorrect Mouse Ray?

I have the following code: Vector3 nearSource = new Vector3(mState.X, mState.Y, 0.0f); Vector3 farSource = new Vector3(mState.X, mState.Y, 3.0f); Vector3 nearPoint = ...
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1answer
129 views

How should I update vectors, et cetera, in a time-based fashion?

I'm trying to write something I believe is straightforward but wanted to check that I'm doing it right. All I want is to update the position of a 2D sprite based an acceleration and velocity. I'm ...
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1answer
253 views

What can I use to generate 2d vector graphics as a list of coordinates?

I am working on a game that uses simple 2d vector graphics. I want a tool that will let me visually draw things like arbitrary polygons by placing points. A perfect tool would present a grid that I ...
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1answer
39 views

Unable to achieve two finger panning

I'm looking to achieve a two finger smooth pan system in my project. However, the code below does not work, any interaction with the screen doesn't change to position of the camera. I am unsure where ...
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2answers
68 views

How can I calculate the orthographic projection needed to encompass an object with arbitrary rotation?

So I need to set up the dimensions of a orthographic projection that will encompass the entirety of a bounding box when viewed from any arbitrary position. That's an eye (programmer art); and the ...
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1answer
57 views

LibGDX/Java - Trying to find the vector from one object to another

I want to add springs in my game that work like the ones in sonic - i.e. if you can't get over an obstacle you have to hit a spring which sends the main character flying towards another spring that ...
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1answer
134 views

Raycast Flashing problem

Can anyone tell me what is wrong with me code? If you can see, whenever the player is in range of the raycast, the enemy turns red. But for some reason, even when the player has meet the requirement ...
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1answer
153 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
386 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
1k 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
362 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
57 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
2k 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
945 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
756 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
123 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
127 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
368 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
538 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
350 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
784 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
37 views

Rotate an objects velocity

I have a collision system (in 3D but for the purpose of the question assume 2D) where I want to calculate the new velocity (stored as a vector) after a collision. What I have is the velocity of the ...
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0answers
37 views

Find camera coordinate of vanishing point

Given a vector and a camera (position, angle, up vector, field of view, etc), how would I find the vanishing point of the vector in camera space?
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1answer
138 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 ...
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1answer
127 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
259 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
191 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
892 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
115 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
475 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
350 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
670 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
4k 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, ...