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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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
65 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
52 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
95 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
67 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
43 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
88 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
189 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
83 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
114 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, ...
7
votes
1answer
139 views

Path following with Asteroids-like movement. Time to complete path

I'm currently learning about how to do this, but it's best to post the problem beforehand. (posting on Physics and GameDev, as you guys know your math) It's quite difficult to explain. This specific ...
0
votes
1answer
49 views

Space of Tangent and Bitangent Vectors

I have a really simple question I cannot be sure about the answer. What is the space of tangent (T), and bitangent (B) vectors when we calculate them using vertex positions, and texture coordinates?
-1
votes
1answer
60 views

Moving vector shooting at other moving vector

The following code creates an accurate shot to be made at a moving target from a stationary position. (ie a tower or non-moving vector). It works GREAT, but I need it to consider the movement of the ...
16
votes
5answers
9k views

Do I need the 'w' component in my Vector class?

Assume you're writing matrix code that handles rotation, translation etc for 3d space. Now the transformation matrices have to be 4x4 to fit the translation component in. However, you don't actually ...
1
vote
2answers
88 views

Calculating the vector to catch a falling object

I have two objects in a three dimensional world. One is a ballistic projectile: that is, it is free-falling with some known gravitational acceleration. The other is a catcher that travels with ...
6
votes
4answers
2k views

How do I restrict the movement of a point to within a radius of another?

I have a situation where a sprite's center point needs to be constrained within a certain boundary in 2D space. The boundary is circular, so the sprite is constrained within a radius. This radius is ...
2
votes
0answers
32 views

Weird warping with per-vertex normals

I've had this little problem for a while now, where for some reason my calculations for per-vertex normals results in a weird distortion or warping, skewing my lighting, shading, and reflection ...
2
votes
1answer
66 views

How do I create a rocket projectile that is “dropped”, then accelerates toward the enemy?

I'm making an Asteroids-like game. I've successfully implemented linear bullets. Now I want to add some rocket-styled bullets, with a certain flight path: The rockets should be "dropped" back first, ...
1
vote
1answer
51 views

How to find if an object is facing another object given position and direction as separate vectors

I found a very helpful post about exactly what I need here. It uses dot products to which is what I'm specifically looking for. It talks about players facing monsters basically. They give a helpful ...
0
votes
1answer
51 views

In unity, how do I rotate a vector in relation to the player?

I am making a radar script in a unity FPS game project I am making for class. I already have a working example of a radar script that works in relation to the player's position. However the rotation ...
0
votes
1answer
246 views

Unity3d - Transform rotation(angle) help

Im trying to rotate an object 90 degrees to the left but instead of rotating straight left it rotates 270 degrees to the right. Here's the part of the code which controls the rotation: ...
1
vote
2answers
77 views

Clamp view direction vector to nearest axis

In JMonkeyEngine, given any view direction Vector3f instance, I'd like to get a new vector facing the nearest x or z axis (positive or negative), with y set to 0. For example [-0.99915564, ...
0
votes
1answer
45 views

Camera will not move between given points, stuck at first given point

[EDIT: Working code added] [Original question] I'm putting together a "raid cam" or "overview cam" for a given map in my shooter for an observing player to use to fly down a given preset path (to ...
0
votes
1answer
50 views

Direct3D - Get screen coordinates for printing multiple text elements

I have a function that I use to print text PrintText(char* text) that stores the text to a vector, which is then displayed if the vector is not empty. I'm trying to figure out how can I correctly ...
0
votes
4answers
247 views

How to check distance between two different vectors?

So I have a very basic racing game, where I would like the car to stop once it hits the finish line. Respectively when the distance between the car and the finish line hits or goes under 0 the car ...
1
vote
3answers
217 views

2D Rendering Based On Y Coordinates

I'm trying to build an RPG worldbuilder. I have seperate classes for images. Like this. Object1::Object1(int x, int y, CSDL_Setup *sdl_set, int *p_CamX, int *p_CamY) { X_pos = x; Y_pos = y; ...
1
vote
1answer
69 views

scrolling ruining bullet physics

the code below is the bullet class for my shooter game in pygame. as you can see if you run the full game (https://github.com/hailfire006/economy_game/blob/master/shooter_game.py) the code works ...
2
votes
1answer
159 views

Unity 3D - Rotate towards object with random offsets

Title is a little confusing, but let me explain: I want to make the enemies look at the player, and shoot at him, with random precision, meaning that one time the enemy will shoot a little bit to the ...
1
vote
3answers
829 views

Create random polygon shapes

I want to make a random shape made out of points. I want the points to create a polygon shape. Is there a clever way to create a random shape like this? Im thinking going throug X points and giving ...
1
vote
2answers
210 views

Unity 3D - Confine a gun rotation within certain degrees

I am having troubles making my gun rotate up and down, and have limits, for example, I want the down limit to be 0 degrees, and the up limit to be 90 degrees. Currently I can't figure out how to ...
2
votes
3answers
155 views

Unity - Check if object is facing Vector3 coordinates

I am having a hard time figuring this out, I want to have objects that move around randomly, and when they get new coordinates to move towards, face them, and then move. Here's explained: Target ...
1
vote
1answer
168 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 ...
0
votes
0answers
35 views

Finding vectors to create an inner border for a mesh

I'm looking to create an inner border for generated polygons, which function as provinces in my game. As an example: I have the outer black vectors, that I use to generate the mesh for the ...
2
votes
1answer
96 views

How to calculate if a point is contained in rectangular camera viewport with rotation?

I am working with my camera, and am trying to improve it so that I can calculate if a world point is on screen, taking rotation into account. Currently, my camera rectangle is calculated as so: ...
1
vote
1answer
64 views

libgdx Vector.cpy question

Why do people use this: public void set(Vector2 v) { this.vector2 = v.cpy(); } insted of just using: public void set(Vector2 v) { this.vector2 = v; } What I don't know that I should ...
0
votes
1answer
2k views

Unity3D Get object size in order to be used in Vector3 coordinates

I have a plane in Unity in 3D project, and I want to get its boundaries so I can use them in random function for getting Vector3 coordinates. Currently I am trying like this GameObject ground; void ...
-1
votes
2answers
73 views

How to get a pleasant path accelerating to a point

I am having trouble moving an object to a target position with a maximum acceleration limit. If i just accelerate towards the target the object will fly in a doughnut a few times before hitting the ...
3
votes
1answer
58 views

Finding coordinate in radius

Hello i have two points (Vector3) A and B. And have a radius r How can i find a coords of point P in a circle by angle?
0
votes
0answers
34 views

Making a node map with PNG alpha channels

I currently creating a 2d game that requires the usage of boats that travel from one country to another. The countries are individual objects with there own png. Nehow I've got the original map of the ...
2
votes
1answer
4k views

Adding 2D vector movement with rotation applied

I am trying to apply a slight sine wave movement to objects that float around the screen to make them a little more interesting. I would like to apply this to the objects so that they oscillate from ...
5
votes
3answers
2k views

What is a direction vector and why should it be normalized?

I've been trying to get the hang of vectors and I read Wolfire's blog about linear algebra and I seem to understand most stuff except when it comes to storing a direction as a vector and using it by ...
-2
votes
2answers
125 views

In XNA, how do I make a sprite move towards another?

I am making a shoot-em-up with a player-controlled sprite with a gun: I have most of the game working, but I have gotten to the point where I need to load in the enemy characters and make them move ...
1
vote
1answer
50 views

Why can't CSS Sprites handle vectors?

Almost all the documentation available either says that "sprites are bitmaps" or that "css sprites must be bitmaps". Is there a specific reason for this? Is it, in fact possible to create a css sprite ...
0
votes
0answers
198 views

how to move an object to the mouse in Java

I have just recently started using Java, literally 2 days ago, and I have run into an issue. While I have been easily able to figure out most of the syntax and methods, because I have used multiple ...
1
vote
2answers
89 views

Malformed/Pixelated Vertex Normals

I am trying to generate vertex normals for a given triangles/vertices list with the following code: **BASE METHOD:** private void CalculateNormals() { for (Int32 i = 0; i < m_Meshes.Count; ...
2
votes
1answer
62 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 ...
0
votes
1answer
749 views

Unable to stop navmeshagent for rotation before moving

I'm trying to get the NavMeshAgent to rotate before calculating a path and proceed walking. I stumbled upon a thread that said this can be done by manually rotating the object first. However, I am ...
0
votes
1answer
70 views

Unable to get object to rotate to looked position?

I'm trying to get an object to smoothly rotate towards a clicked point in my terrain. However, my code only yields jittery movements in the other direction. Any help will be greatly appreciated. ...
0
votes
1answer
128 views

Working but flawed bullet spread (vector math)

I'm trying to implement random bullet spread into my game, and I've managed something that works, but is consistently flawed. The spread doesn't vary depending on the distance the mouse is from the ...