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

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464 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 ...
2
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1answer
155 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 ...
2
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1answer
146 views

Rotation independent rotation

I came up with some cube rotating, but I could not make it smooth and easy to use because as the cube turned - the keys that handle the turning changed their purpose. Link to demo. The demo rotation ...
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2answers
6k views

Rotate sphere in Javascript / three.js while moving along x/z plane

I have a sphere/ball in three.js which I want to "roll" around on the x/z plane. For the z axis I could simply do this no matter what the current x and y rotation is: sphere.roll_z = ...
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2answers
4k views

Rotation matrix derived from quaternion is opposite of expected direction

When I calculate a rotation matrix from a quaternion, it seems to be in the opposite direction. For instance: For a rotation of +45 degrees about the Y-axis, I would expect to get the following ...
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1answer
533 views

Finding a suitable axis-angle to avoid gimbal lock

In OpenGL the camera faces the -z axis with the +y axis pointing up. I am using quaternions to represent the orientation of my objects (which works well) and am trying to do the same for the camera. I ...
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1answer
2k views

How can I create my mesh so that textures applied to it are NOT rotated 90 degrees in Unity 3D?

I'm trying a really simple test in Unity 3D. I want to render a texture on the simplest plane possible. So, I've created a two-triangle plane in Blender, then imported it into Unity. From there, I ...
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1answer
746 views

Image spinning in c#

I'm currently in the process of making a top-down shooter for my programming class, and one idea I had, but don't exactly know how to implement is image rotation in order to spin the object ...
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1answer
2k views

XNA - Use Mouse To Rotate & Arrow Keys To Scroll A Linearly Wrapped Texture:

Using XNA I'm working on my first, relatively simple, videogame for the PC. At the moment my game window is 1024 X 768 and I have a 'Starfield' linearly wrapped background texture 1280 X 1280 in ...
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1answer
4k views

2d tank movement and turret solution

I'm making a simple top-down tank game on the ipad where the user controls the movement of the tank with the left "joystick" and the rotation of the turret with the right one. I've spent several hours ...
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2answers
200 views

Can't figure get the conversion from cartesian to spherical(“polar”) correctly for my orbiting camera

The two angles from the polar coordinate system are defined as hRotation and vRotation This is how they are converted from polar to cartesian: // Get the distance between the object and the ...
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1answer
82 views

Given a 3d goal point and a turn rate in radius, find max speed to reach goal

I'm working on a 3d space sim with AI agents flying ships through space. I am trying to get them to follow a waypoint path nicely, which involves figuring out how fast they can be travelling and still ...
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1answer
21 views

Finding specific coordinates on a rotating line

I'm currently working on a mobile game which mainly consists of a rotating line and a ball. The line rotates 0.500 degrees clockwise around its center every frame. The ball is at first positioned in ...
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1answer
137 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
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1answer
83 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: ...
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1answer
88 views

Problem with Rotation - C#/XNA

I have a projecile(Hook) and the tail of the projectile(yellow balls) TailProjectile class draws a ball at the exact position of the projectile(hook) and let it there until the projectile ends I'd ...
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1answer
277 views

How to rotate an object along its trajectory path?

I have a missile launcher that uses initial velocity for the trajectory. I edit the launch angle from the editor, and then the script calculates the initial velocity required to land the missile to ...
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2answers
97 views

Combining two independent rotations relative to the world frame

I am implementing a mouse rotation which works by accumulating the X-Y delta between frames to yaw and pitch rotation angles. The problem is that I wish rotations to be independent of each other. But ...
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1answer
177 views

Get quaternion between two objects on sphere

In a planetary gravity environment objects are represented in the following way: struct object { struct quaternion quat; // quaternion to represent the rotation between the object and the center ...
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1answer
157 views

How can I trigger an event each time the rotation of my rigidbody2D is at a given value?

I would like to trigger an event each time my rigidbody2D is at a particular value. The event should only be triggered once for each given value per complete object revolution. Initial attempts at ...
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1answer
906 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
602 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 ...
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2answers
466 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 ...
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1answer
3k 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 ...
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1answer
880 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 ...
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1answer
66 views

Euler adjustments between two quaternions

I have two quaternions, q1 and q2. If my object's current rotation is at q1, but I need to get it to q2, what would be the process to figure out how much rotation I apply to x, y, and z in order to ...
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51 views

Rotating kinematic object around a moving point Box2D

I'm new at Box2D and I am making a simple game where you control the rotation of the maze and the gravity leads the ball to the exit. The game looks like: The problem: I want to rotate the maze, ...
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88 views

smoothly recenter view over time

I'm currently using the Google Cardboard SDK for Unity to build a fighter pilot simulator. What I'm currently trying to do is recenter the view(CardboardHead) smoothly over time when the user looks ...
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1answer
260 views

In UE4, how do I turn my character's body together with the camera?

I made a simple punch animation in Blender and exported it into Unreal Engine 4. In-game, the character appeared from a 3rd-person perspective, but I made it look like first-person by adjusting the ...
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1answer
101 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: ...
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0answers
273 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 ...
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0answers
44 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: ...
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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 ...
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4answers
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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). ...
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2k 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 ...
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1answer
184 views

How do I ADD gravitation to a rotation matrix?

I have ported the Matlab script from https://instruct1.cit.cornell.edu/courses/bionb441/LSystem/ to POV-Ray and everything works fine (although I'm not quite sure why). To navigate a "turtle" through ...
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1answer
2k 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, ...
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295 views

How to set object's / node's absolute rotation correctly?

Usually when I want to rotate an object/node in my Ogre scene I call the node's rotate() method. That rotates the node locally relative to it's current rotation. So for example, when I start with 0 ...
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0answers
147 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 ...
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779 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 ...
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1answer
504 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] ...
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3answers
5k 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 ...
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vote
1answer
1k 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 ...
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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 ...
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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 ...
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3answers
979 views

How to rotate to a target position over time

I know how to do rotations to vectors, but how do I rotate over time? For instance say I made a function RotateTo(vec2 iPosition, float iTime); so it rotates to iPosition over iTime - how would ...
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5answers
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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 ...
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vote
1answer
9k 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 ...
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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 ...
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3answers
1k 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 ...