# Tagged Questions

A mathematical concept that can be used to express position, direction or velocity and which can simplify or outright trivialise spatial problems.

204 views

### How to rotate a triangle towards the point in Qt?

I have an issue with items rotating. I have a point and a triangle which needs to be rotated with its apex point towards the taregt point. The right side of the picture represents how it is should to ...
66 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 http://blog.gemserk.com/2012/07/03/drawing-a-projectile-trajectory-like-angry-birds-using-...
82 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 ...
44 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. (It'...
109 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 ...
115 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 {...
92 views

### Find your value between four values in a grid based on distance, Unity

Please note: Originally posted in stack overflow, redirected due to nature of problem. I am making a procedural mesh game. I am trying to calculate the temperature for the player's current chunk by ...
224 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 = ...
89 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 ...
143 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, ...
62 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 ...
33 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 passes....
68 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, ...
57 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 ...
93 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 ...
55 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 ...
75 views

### Rotating a 4D matrix about the Y axis with an X-Z vector

I should mention that I'm pretty new to Matrices and will probably need a layman's answer to my question. I have a 4D matrix which represents the rotation of an object in 3D space. I have a ...
290 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: ...
80 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....
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 ...
617 views

### calculating torque from angular momentum considering inertia moment

so I am trying to determine exactly how much torque to apply to a 3d model to make it rotate at a particular rate. I apply force from the location of each engine on the craft so if one breaks the ...
54 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 ...
51 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?
142 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 ...
238 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; ...
170 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 ...
70 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 ...
235 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 ...
188 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 ...
112 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: ...
66 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 know?...
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 ...
59 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?
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 ...
53 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 ...
103 views

### Would Raycast suffice for a game clock based on sun position?

I need help with some logic in my script. I created a dynamic day/night cycle that works fine in itself, but I want to add a game clock that works off the initial position of the sun (Directional ...
239 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 ...
91 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; ++...
69 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 ...
873 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 ...
84 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. ...
139 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 ...
48 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 ...
70 views

### How do I convert two vectors into a bounding box with 8 vertices?

I created two vectors named bboxmin and bboxmax using the functions vector3 applymin_xyz() and vector3 applymax_xyz(). How do I convert them to 8 vertices,so I can test cull with them?
69 views

### Controlling the movement of player by sprite using Mouse

I want to move the player by pressing down on the mouse and moving around by dragging. The player won't move to the position of the mouse. Instead it should be relative to the players current position....
135 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 ...
208 views

### Endless Running Game - Changing Lane Function in JAVA

I am developing a kind of vertical endless running game, where the character has 4 possible lanes to be in. I am using libGDX and want the character to change lanes by adding a horizontal velocity to ...
312 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 ...