# Tagged Questions

32 views

### Unity 2D angular velocity center [duplicate]

I try to add angular velocity to my GameObject with this command: rigidbody2D.angularVelocity = Random.value * tumble; All works, but I want center of velocity be in the center of my rigidbody, but ...
32 views

### XNA 2D Stencil Buffer Rotation

I am currently working on a 2d game related to planets and am trying to get a stencil buffer working with rotation. I currently have a stencil buffer found from another related answer but it refuses ...
159 views

### Calculate turn rate between xy and target xy on a moving sprite with variable speed

My First question on here so be kind... I am writing an aerodrome simulator in as2, I need to calculate a turn rate between 2 points so that the aircraft turns nicely. I have tried a few things but ...
101 views

### LWJGL Rotating is moving

I am trying to rotate my QUAD even just a little bit. I have read pages like http://www.java-gaming.org/topics/lwjgl-tutorial-series-moving-and-rotating-triangle/30679/view.html In my render() ...
52 views

### How should I model rotation caused by bounce friction? [duplicate]

In my Java2D simulation, I have a disc which, when it bounces off the boundary of a 2D region, begins to rotate, as if it had gotten some spin from the wall. I'm having trouble relating the ...
199 views

### How to make bullets follow a rotating sinewave pattern

I am trying to replicate the wave gun from Super Metroid where the bullets fly along a sine wave path. The cool part is that you can shoot in 8 directions and the bullet still follows the sine as if ...
615 views

### How do I make an object face the mouse position, but only on one plane?

I want a game object to turn and look towards where the mouse was clicked (in world space). It works well when considering all 3 dimensions, but I really only care for the plane formed by the x and z ...
133 views

### How do I rotate a bounding box together with a sprite?

I have a game object with a sprite that can rotate. It's a rectangle. I need its bounding box to rotate with it. How do I make sure that they can both rotate, but they're always both at the same ...
51 views

### Draw object to screen without being affected by rotation / zooming [duplicate]

I have a 2D game, with a camera that follows the main player. In the game the camera may also rotate the view around the player / zoom in or out on the player. Let's say I want to add a mini-map to ...
75 views

### Angluar movement

I'm making a little game where you are a spaceship and you fly around in 2d using the A and D key to rotate and the W key to accelerate. Now my problem is if i turn my ship it doesn't go into the ...
587 views

### Rotating object around moving object/player in 2D

I am trying to implement a camera which rotates around the world around the player. I have found many solutions online to the task of rotating an object about the origin, or about an arbitrary point. ...
1k views

### Rotate image around a specified origin

I'm trying to rotate my Turret.png (small Gunhead with a laser in front) towards the mouses location on the screen. I tried just using my method for rotating projectiles towards the next step on their ...
422 views

### Java moving image to where it is facing

I am trying to make an Asteroids type game. I searched and tried everything to move an image along its angle (as radiant). Using my knowledge of trigonometry I made the following calculation: x += ...
150 views

### Rotate 2d sprite towards pointer

I'm using Crafty.js and am trying to point a sprite towards the mouse pointer. I have a function for getting the degree between two points and I'm pretty sure it works mathematically (I have it under ...
2k views

### How to smoothly rotate a vector in a direction?

I'm looking for an easy way to achieve the following: Object A, B { Vector2D position; Vector2D orientation; } update(elapsed) { //rotate A's orientation in B's direction by x * elapsed ...
363 views

### How do I make an arrow line up with a bow when rotating them?

I am trying to create a bow and arrow animation in which the player can drag downwards to increase the bow strength (see the image) and release it to hit a target. I can't get the arrow to align ...
279 views

### Grouping surfaces in pygame to get an object with two movement points

I would like to create a simple tank using pygame. One would drive the tank by controlling he velocities of two caterpillar tracks. They should be the two single movement points of the vehicle. I'm ...
379 views

### How to make a stack stable? Need help for an explicit resting contact scheme (2-dimensional)

Previously, I struggle with the sequential impulse-based method I developed. Thanks to jedediah referring me to this paper, I managed to rebuild the codes and implement the simultaneous impulse based ...
1k views

### Rotating 2D Object

Well I am trying to learn openGL and want to make a triangle move one unit (0.1) everytime I press one of the keyboard arrows. However i want the triangle to turn first pointing the direction where i ...
536 views

### Rotating multiple points at once in 2D

I currently have an editor that creates shapes out of (X, Y) coordinates and then triangulate that to make up a shape of those points. What will I have to do to rotate all of those points ...
3k views

### How do I rotate a sprite so that it is 'pointing' in the direction it is moving?

I have a sprite, e.g a missile, heading in a certain direction (using a velocity vector). How do I figure out its how much to rotate it so that it gets drawn 'pointing' in the direction it is ...
406 views

### Joystick example problem for android 2D

I've searched all over the web for an answer to this, and there are simular topics but nothing works for me, and I have no Idea why. I just want to move my sprite using a joystick, since I'm useless ...
582 views

### Rotating Sprite around Y-Axis (2D)

I'm going to be creating a game soon, and part of it involves spinning sprites. The sprites will be spinning around the Y-Axis (imagine a spinning plate on top of a stick, where the stick stands up ...
799 views

### Matrix rotation of a rectangle to “face” a given point in 2d

Suppose you have a rectangle centered at point (0, 0) and now I want to rotate it such that it is facing the point (100, 100), how would I do this purely with matrix math? To give some more specifics ...
569 views

### Passing an objects rotation down through its children

In my topdown 2d game you have a player with a sword, like an old Zelda game. The sword is a seperate entity, and its collision box "rotates" around the player like an orbit, but always follows the ...
2k views

### Can I use SpriteBatch when drawing sprites on a rotating 3D plane

I'd like to have my plane of sprites rotate similarly as in this game (YouTube Video). So basically, everything is drawn in 2D, but the 2D plane is then "rotated in 3D" (or camera is rotated). When ...
3k views

### Rotation of images in Slick2D

I have have a rotation problem in the Slick2d library, the image is just not rotating (ie I set a rotation but no result is shown). Here is the rotation code: if (input.IsKeyDown(Input.KEY_LEFT)) { ...
822 views

### Is it better to track rotation with a vector or a float?

In XNA, you can see that to draw a rotated sprite with SpriteBatch, you'll need a float describing the angle in radians. I'm used to making games in OpenGL. I just want a rapid prototyping ...
931 views

### How can I make a sprite move in the direction it's facing using radians?

I am using PGELua for the PlaystationPortable. I would just like to know how to make a 2D sprite move in the direction that the sprite is facing. When the sprite is blitted to the screen it should ...
762 views

### I need help with 2D collision response (of stacking rotating polygons, with friction and gravity, for a game)

Hi I am looking for suggestions on how to write a collision response for game programming purpose (so not a scientific simulation). I am dealing with 2D polygons that are rotating, and I want them to ...
2k views

### Calculating the rotational force of a 2D sprite

I am wondering if someone has an elegant way of calculating the following scenario. I have an object of (n) number of squares, random shapes, but we will pretend they are all rectangles. We are ...