A mathematical concept that can be used to express position, direction or velocity and which can simplify or outright trivialise spatial problems.
0
votes
1answer
28 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
0answers
15 views
How to unbind a sprite in an updating vector? LIBGDX framework [closed]
How to unbind an updating vector to a sprite? I am using Libgdx framework. here is my code
public class VectorSample extends GDX_TEST implements InputProcessor {
Texture ball,bullet,guider;
...
-1
votes
1answer
100 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 ...
7
votes
3answers
214 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 ...
0
votes
0answers
40 views
JavaScript “Floats”, or ThreeJS wrong positioning?
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
186 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
111 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
57 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
83 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
262 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
144 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
140 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
100 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
187 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
284 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 ...
4
votes
3answers
328 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 ...
0
votes
0answers
52 views
Uses for vector projection?
My previous question was solved by vector projection. Thus I spent some time studying it (Few helpful links: Interactive projection, short video and a longer video.).
There were plenty of sites that ...
1
vote
0answers
60 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
196 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
95 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
237 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
65 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
120 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
93 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
202 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
595 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 ...
0
votes
3answers
255 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 ...
2
votes
3answers
314 views
Oriented Bounding Box - How to?
I've been trying to write my own collision code, less because I want to, more because I want to understand its working.
To do this, i've been working off of the popular collision book i'm sure you've ...
0
votes
4answers
156 views
How much to modify yaw? XNA 4.0 [duplicate]
Heres a picture that explains better than my words can
For rotating an object I'm using quaternions.
CreateFromAxisAngle(vector3.Right,yaw)
Maybe this isn't how I should be doing it but I also ...
8
votes
3answers
447 views
Vector3 vs. Vector2 - performance, usage?
I'm currently playing around with XNA, and creating a simple 2D platformer. I was thinking of adding multiple layers to make it a little bit of challenge.
In stead of having a Vector2 for my ...
0
votes
1answer
117 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 ...
1
vote
1answer
87 views
Confusing with an articles wording on Clamping a Vector2
I have been reading an article on Collision Detection and how to resolve it.
http://www.wildbunny.co.uk/blog/2011/04/20/collision-detection-for-dummies/
In the section describing an AABB vs Circle, ...
-4
votes
2answers
159 views
enemy shooting towards FPS [closed]
WELL first of all I want you to see my game (its deployed on heroku cloud) :
http://still-escarpment-3701.herokuapp.com
(It takes almost 10 sec to load so please wait for couple of sec)
I have ...
2
votes
1answer
163 views
Min/Max of two vectors?
This seems like a simple question, but i'm having trouble searching the internet for it.
In XNA, during a collision detecting method, I would determin the minimum of some vectors.
// Get the minimum ...
0
votes
0answers
40 views
Transform a Screen Delta
I have a delta in screen coordinates that I want to transform to a 3d delta in world space.
The delta is in this case a movement across the (x,y) coordinates in screen space on the near projection ...
1
vote
1answer
279 views
Understanding math used to determine if vector is clockwise / counterclockwise from your vector
I'm reading Programming Game AI by Example by Mat Buckland. In the Math & Physics primer chapter there's a listing of the declaration of a class used to represent 2D vectors.
This class contains ...
-1
votes
3answers
322 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, ...
1
vote
2answers
183 views
convert orientation vec3 to a rotation matrix
I've got a normalized vec3 that represents an orientation.
Each frame of animation, an object's orientation changes slightly, so I add a delta vector to the orientation vector and then normalize to ...
3
votes
1answer
342 views
Raycasting tutorial / vector math question
I'm checking out this nice raycasting tutorial at http://lodev.org/cgtutor/raycasting.html and have a probably very simple math question.
In the DDA algorithm I'm having trouble understanding the ...
2
votes
3answers
521 views
Converting Degrees to X and Y Coordinate change
I am using a float positioning system in my game. IE float x,y,z
now I want to get the location of the mouse, then to fire an arrow to it.
X0 = the players X location
X1 = the mouse X location
Y0 = ...
1
vote
2answers
603 views
Line Intersection from parametric equation
I'm sure this question has been asked before. However, I'm trying to connect the dots by translating an equation on paper into an actual function. I thought It would be interesting to ask here instead ...
0
votes
1answer
89 views
Using NumPy arrays as 2D mathematical vectors?
Right now I'm using lists as position, velocity, and acceleration vectors in my game. Is that a better option than using NumPy's arrays (not the standard library's) as vectors (with float data ...
15
votes
7answers
520 views
Do I need a Point and a Vector object? Or just using a Vector object to represent a Point is ok?
Structuring the components of an engine that I am developing along with a friend (learning purposes), I came to this doubt.
Initially we had a Point constructor, like the following:
var Point = ...
1
vote
2answers
118 views
Determining if something is on the right or left side of an object?
I have a character in a 3D world which is facing an arbitrary direction on a flat plane, the player can click on the left or right side of the character and based on which side is clicked on a ...
0
votes
1answer
151 views
Tilting towards turn direction (for a motorbike)
I have a motorbike which moves along based on a direction vector, I set its forward direction to the direction it's moving.
What I'd like to also do with it is have the motorcycle tilt in the ...
1
vote
1answer
151 views
How do I get the axes for SAT collision detection
In SAT collision detection how do I calculate the axes for projection?
2
votes
1answer
167 views
How to shift a vector based on the rotation of another vector?
I’m learning 2D programming, so excuse my approximations, and please, don’t hesitate to correct me. I am just trying to fire a bullet from a player. I’m using HTML canvas (top left origin).
Here is a ...
3
votes
2answers
137 views
what does AngleVectors method in quake 3 source code does
I just downloaded quake 3 for learning purposes.
I know some of some linear algebra(basic vector math ie: dot,cross product).
However I can't decipher what below method does, I know what is yaw,pitch ...
0
votes
1answer
89 views
How to Draw texture between 2 Vector3
My scenario:
RTS combat style, 1 unit fires beam on another unit
My problem is i want to draw a flat texture between 2 Vector3 points. I have looked at various Billboarding styles but that doesn't ...
2
votes
1answer
160 views
Turning to face mouse
Given three points on the same Y plane;
A ship
A point along the ships heading
A mouse cursor
How can I find which direction and angle the mouse cursor is from the ships heading?
I have a limited ...
