Rotation is the circular movement of an object around a specific axis.

learn more… | top users | synonyms

2
votes
1answer
533 views

Three.js camera turning leftside right

In Three.js I am trying to implement an orbiting camera can be rotated around the x and the y axis. I am using these two functions: function rotateX(rot) { var x = camera.position.x, ...
2
votes
2answers
570 views

How do I apply 2 rotations about different points to a single primitive using OpenGL

I'm working on a 2D top-down shooter game that has a rotation feature like Realm Of The Mad God such that if you press e the camera rotates around the character in a clockwise direction and q rotates ...
2
votes
2answers
453 views

Rotating a 2D Skeleton

I am currently implementing a 2D skeleton system in C# with XNA, but got stuck in how I would rotate the bones around a skeleton's axis. A basic algorithm that I have figured out already would ...
2
votes
2answers
1k views

Rotating a child shape relative to its parent's orientation

When rotating a shape using a quaternion value I also wish rotate its child shape. The parent and child shapes both start with different orientations but their relative orientations should always be ...
2
votes
1answer
2k views

Flip rotation matrix

I'm doing character control with kinect. I need to mirror the joint orientation because the character faces the player. Somehow by Googling through internet I've done it and everything works very ...
2
votes
1answer
788 views

Positioning a 2D image after rotation

Using SDL_gfx's rotozoomSurface function to rotate a 38x58 sprite....naturally when it rotates it creates a new surface with a new size, and the rotation isn't going around the center point. I am ...
2
votes
2answers
2k views

Weird rotation problem

I'm creating a simple tank game. No matter what I do, the turret keeps facing the target with it's side. I just can't figure out how to turn it 90 degrees in Y once so it faces it correctly. I've ...
2
votes
0answers
27 views

3D 3-axes rotation into 3D 2-axes rotation

Hello everyone and thanks in advance to anyone who'll help me through this ! I am currently working on the Kinect V2 (for XBox One) to interact with an avatar. I'd like to use the rotation quaternion ...
2
votes
1answer
100 views

OpenGL 2.1 rotation , Gimball lock

I'm working on a little app for a school project , which should be manipulating 3D objects. And i'm stuck with the rotation , as i'm facing what i think is called the gimball lock ? here's a video I ...
2
votes
1answer
65 views

Increment grid by rotation

I'm currently working on a grid for snapping objects side by side. My current script is working fine, but only for game objects which haven't been rotated. Here is an example video of the problem: ...
2
votes
0answers
220 views

Quaternion - rotating rigidBody to particular angle over time

Using Bullet Physics. There's a rigid body that is rotated. For some delta-time I need to rotate that body to have rotation of (0, y, 0) - keep the old y value rotation but reset x and z. The ...
2
votes
0answers
34 views

Xna 4 Model Rotation with inertia not working as expected with variable updates

I am trying to rotate a model with inertia damping with the keyboard. The code works great with a fixed time step but it doesn't behave the same with a variable update frequency. Update method: ...
2
votes
0answers
54 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 ...
2
votes
4answers
900 views

How to set speed of circular motion

Edit 2 - clarification Just to clarify, the issue I have at the moment is how I specify a time (in seconds) for a complete revolution to occur. My delta is fixed and is 1/ticks per second (1/60). ...
2
votes
0answers
1k views

Arcball 3D camera

I have checked multiple threads before posting, but i havent been able to figure this one out. Ok so i have been following this tutorial, but im not using glm, ive been implementing everything up ...
2
votes
1answer
1k views

Problem using glm::lookat

I am trying to rotate a sprite so it is always facing a 3D camera. Object GLfloat vertexData[] = { // X Y Z U V 0.0f, 0.8f, 0.0f, 0.5f, 1.0f, -0.8f,-0.8f, 0.0f, ...
2
votes
0answers
143 views

Pitch (X-axis) rotation problem [closed]

Situation: From a first person perspective (camera position) I want to be able to grab an object and have it fixed to the center center of the screen while looking up-down (pitch) and looking ...
2
votes
0answers
674 views

Rotation of viewplatform in Java3D

I have just started with Java3D programming. I thought I had built up some basic intuition about how the scene graph works, but something that should work, does not work. I made a simple program for ...
2
votes
1answer
441 views

Programmatically determine UVs by rotating a plane along X axis

I'm having a math brainfart while trying to solve what might be a simple problem. I've got a plane in 3d space (it's actually the face of a 10-sided die): Coordinates [x,y,z]: Point_top = [0,0,1] ...
2
votes
3answers
4k views

LWJGL glRotatef() without rotating axes?

Okay so, I noticed when you rotate around an axis, say you do this: glRotatef(90.0f, 1.0f, 0.0f, 0.0f); That will rotate things 90 degrees around the x-axis. However, it also sort of rotates the y ...
1
vote
1answer
938 views

How to get a point to the left/right of a vector

I have a position vector of a point in space and a quaternion for it's rotation. What i'm trying to calculate is a point too the left and a point to the right. I have the position and ...
1
vote
2answers
3k views

XNA advanced rotation 3D

I'm able to rotate any model with any angle I want, where I can not rotate my model around a given point. e.g: My model rotates from the origin assigned in its .fpx file. I want it to rotate related ...
1
vote
3answers
412 views

Inverting matrix then decomposing gives different quaternion than decomposing then inverting the quat

I'm getting different signs when I convert a matrix to quaternion and invert that, versus when I invert a matrix and then get the quaternion from it: Quaternion a = Quaternion.Invert(getRotation(m)); ...
1
vote
2answers
1k views

Transformation order when dealing with Meshes

I have created a player model out of primitive types. To do this I have created a Model class and Component (mesh) class. Each model consists of one or more components my problems start when you have ...
1
vote
5answers
2k views

how to rotate enemy to face player? [duplicate]

Okay so i havebeen rotating my enemy to face the player using float targetrotation = Math.Atan2(playerpos-enemypos); enemy.rotation = targetrotation; (<this line of code i want to change) This ...
1
vote
1answer
1k views

Scene graph in Unity3D

I was wondering if any scene graph-like mechanism is implemented into Unity3D? For example if I have a GameObject, can I add child cubes to it so when I rotate the parent GameObject, the siblings will ...
1
vote
3answers
808 views

Rotation matrix for a 3D vector

I have a direction vector on which I have to apply some rotation to align it to positive z-axis. To use Matrix.CreateRotationX(angle) of XNA, I need the angle for which I'd have to compute cos or tan ...
1
vote
2answers
1k views

“Align” a rotation to a direction

Good day all. I have a 3d object with a random rotation. I can express that object's rotation both through a quaternion or through an euler rotation. Then I have a vector3 normal that I get from a ...
1
vote
2answers
858 views

Matrix Rotation with three Angles

I want to rotate a form with three given angles fo each of the three axis. But the GLM rotation function takes only one angle and a vector as arguments. How can I convert between both formats?
1
vote
1answer
8k views

Rotate to a set degree then stop Unity [closed]

I'm trying to make an object rotate up on the Y axis 90 degrees, then stop. I've got the rotating up bit working fine, it's getting it to stop once it hits 90. Some of the things I've tried include ...
1
vote
1answer
64 views

Why is the camera tilting around the z axis when I only specified x and y?

My goal is to program a camera to point towards the mouse cursor. I attached the following script to the Main Camera. using UnityEngine; using System.Collections; public class CameraController : ...
1
vote
1answer
197 views

How to rotate object not from it's center point but from it's another point?

I am new in unity and I am developing a game where I want to rotate my object I try this code for it. if(Input.GetMouseButton(0)){ if(Input.GetMouseButtonDown(0)){ ...
1
vote
2answers
2k views

LibGdx sprite rotation vs Box2D physics rotation problem

LibGdx sprite rotation vs Box2D physics rotation problem Tearing my hair out on this one. I am an experienced software developer, but very new to LibGdx and Box2D development. I am writing a game ...
1
vote
1answer
2k views

Movement and rotation of bodies in top down game

We are developing a 2D top down game with libgdx using the included box2d as physics engine. We don't want our bodies to accelerate but to instantly move with the wanted velocity. The bodies are ...
1
vote
1answer
1k views

Rotate triangle so that its tip points in the direction of the point on the screen that we last touched

OpenGL ES - Android. Hello all, I am unable to rotate the triangle accordingly in such a way that its tip always points to my finger. What i did : Constructed a triangle in by GL.GL_TRIANGLES. Added ...
1
vote
3answers
238 views

Projectile Rotation During Flight (Tank Game)

I have a tank firing projectiles into the air. I want the projectiles to be rotated relative to their position along their flight path. See the diagram I drew in the image below. At any given point ...
1
vote
2answers
60 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 ...
1
vote
1answer
56 views

Rotating a square rendered on a Bitmap

I'm writing a Software Renderer for fun/learning. Basically, it's just a giant array of integers which contain hexadecimal values (representing colour) that are rendered to the screen.... int ...
1
vote
2answers
576 views

What torque should I apply in Bullet to maintain a vertical orientation?

I have a RigidBody in Bullet. Each frame, I want to apply torque to correct its orientation toward an upright position (i.e. near-zero pitch and roll). I know its angular velocity and orientation. ...
1
vote
1answer
1k views

Libgdx Do a fixed rotation for orthographic camera

Im trying to rotate my orthographic camera in the render loop to a fixed angle, but I can only make the camera spin with the code I got: in the create OrthographicCamera camera = new ...
1
vote
2answers
271 views

Detecting collision of two sprites that can rotate [duplicate]

I have a problem with collision detection in a 2D Java game. Normally, what I would do is create a getBounds() method for an object that can collide with other objects. This method would return a new ...
1
vote
1answer
297 views

Sprite rotation

I'm using OpenGL and people suggest using glRotate for sprite rotation, but I find that strange. My problem with it is that it rotates the whole matrix, which sort of screws up all my collision ...
1
vote
1answer
959 views

Need to translate a Rotation Matrix to Rotation y, x, z OpenGL & Jitter for 3D Game

I am using the Jitter Physics engine which gives a rotation matrix: M11 M12 M13 M21 M22 M23 M21 M32 M33 And I need it so OpenGL can use it for rotation GL.Rotate(xr, 1, 0, 0) GL.Rotate(yr, 0, 1, ...
1
vote
1answer
3k views

Rotate an object around a point in Ogre3D [duplicate]

Possible Duplicate: How can I rotate about an arbitrary point in 3D (instead of the origin)? I am new to 3D programming and I have been using Ogre3D lately to get a grasp of it. What I am ...
1
vote
1answer
562 views

Detecting pixels in a rotated Texture2D in XNA?

I know things similar to this have been posted, but I'm still trying to find a good solution... I'm drawing Texture2D objects on the ground in my game, and for Mouse-Over or targeting methods, I'm ...
1
vote
1answer
568 views

Rotating a cube using jBullet collisions

How would one go about rotating/flipping a cube with the physics of jBullet? Here is my Draw method for my cube object: public void Draw() { // center point posX, posY, posZ float ...
1
vote
3answers
1k views

XNA create differences in enemies

I created an enemy class for my game. It works well, except for one dilemma. When I spawn more than one enemy, eventually they begin to "overlap" and look like one enemy. I was wondering if anyone had ...
1
vote
2answers
987 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 ...
1
vote
1answer
2k views

Move an object by rotation AS3

I am currently trying to move an object (a square) around the stage in 2D space. Think Cuboid but in 2D platformer space, and vertical walls as well as the ground. The idea is that during each ...
1
vote
1answer
87 views

Determine which face of a cube is facing the camera

I have a Cube with a unique color for each face. I made a script where I can swipe and rotate the Cube in increments of 90 degrees in each direction. what's the best way to determine which face of a ...