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

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XNA 3D cube rotation problem

I am new to game programming and still trying to clear up my basics. I am stuck with a problem and unable to resolve on my own knowledge. I am trying to rotate a 3d cube in MonoGame (Similar to XNA) ...
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1answer
311 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 ...
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2answers
93 views

Do I need to store a generic rotation point/radius for rotating around a point other than the origin for object transforms?

I'm having trouble implementing a non-origin point rotation. I have a class Transform that stores each component separately in three 3D vectors for position, scale, and rotation. This is fine for ...
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3answers
282 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 ...
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1answer
264 views

Repelling a rigidbody in the direction an object is rotating

Working in Unity, I have a game object which I rotate each frame, like so: void Update() { transform.Rotate(new Vector3(0, 1, 0) * speed * Time.deltaTime); } However, I'm running into problems ...
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1answer
360 views

libgdx rotation (animation, arrays) issues and help needed

well i am a noob at java and libgdx. i got the homing bullet working with the help of someone. now i am smashing my head as to how i can make it rotate so it faces the ball (which is the main ...
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2answers
124 views

what's wrong with my lookAt and move forward code?

so am still in the process of getting familiar with libGdx and one of the fun things i love to do is to make basics method for reusability on future projects, and for now am stacked on getting a ...
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0answers
30 views

How to rotate a trigger actor in UDK?

Working on a project and I need a trigger actor to detect a custom projectile type I've made. I would use a KActor with a TakeDamage event, but KActors despawn my projectiles. The issue is that I ...
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3answers
442 views

How to rotate a set of points on z = 0 plane in 3-D, preserving pairwise distances?

I have a set of points double n[] on the plane z = 0. And I have another set of points double[] m on the plane ax + by + cz + d = 0. Length of n is equal to length of m. Also, euclidean distance ...
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52 views

Issue with turntable rotation openGL

I am trying to implement turn table like rotation in my openGL app. In turn-table like rotation, z-axis is not supposed to roll. But in my app z-axis rolls like anything when I try to rotate the ...
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1answer
142 views

Can I have a fixed-angle sprite with a non-fixed-angle CircleCollider2D?

In Unity2D, can I have a fixed-angle sprite with a non-fixed-angle CircleCollider2D? I would like to move my character using the circle physics (without fixed-angle), but display him always as if he ...
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2answers
100 views

How can I find the difference between rotations represented as angles in [0, 360]?

What is the easiest way to find the difference between two 2D rotations/directions? I want to test if one rotation is within 10° of another. I would just subtract, but there are some problems ...
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1answer
746 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 ...
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33 views

Why the rotation matrix of X(θ1)Y(θ2)Z(θ3) can be viewed as extrinsic rotation of order ZYX and intrinsic order of XYZ?

As title, from wiki and OpenGL red book(7e) I found the expression v' = R_x * R_y * R_z * v can be viewed as Rotate vector v about local x axis, and y axis, finally z axis. Rotate vector v about ...
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1answer
83 views

Incomplete mesh using DrawIndexedPrimitives after rotating mesh

Through help on this site I was able to draw the triangles of an unrotated, nonscaled nontransformed mesh created in Blender and exported to OBJ, accurately imported through Assimp and rendered in XNA ...
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1answer
149 views

Bullets won't shoot out of barrel in top-down shooter

So I am working on a top down shoot and have been stumped on why my bullets refuse to come out of the barrel of the gun. I know about the rotation equation which is x2 = x * cos(theta) - y * ...
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0answers
138 views

Unity crashes completely when I rotate my objects [closed]

I've started my first tiny Unity project and after 20 minutes I run into a brick wall. My goal was to create a Android 2D game with falling polygons, that you have to click and they disappear. ...
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3answers
252 views

How do I disassemble a 3x3 transformation matrix into rotation and scaling matrices?

I have a transformation matrix that rotates and scales. Is there any easy way to disassemble it into the original rotation and scaling matrices? For instance: M = R * S; // I need f and h such that ...
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1answer
124 views

Unity - Quaternion - Rotate / Unrotate Error

I'm trying to unrotate a quaternion, aligning it with the axis, and then rotate it back to where it was originally. But with every iteration it seems to lose precision and just after 20 iterations the ...
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2answers
375 views

Matrix rotation wrong orientation LibGDX

I'm having a problem with matrix rotation in libgdx. I rotate it using the method matrix.rotate(Vector3 axis, float angle) but the rotation happens in the model orientation and I need it happens in ...
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1answer
95 views

Camera rotation around point, but without centering

Let's say i have the following: Point somewhere in space Camera with position and orientation (up, right, forward) I want to rotate camera around the point, but also keep this point in same place ...
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126 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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86 views

How do I get a sprite's angle after collision?

I'm using Cocos2d (version 3) and I want my hero sprite to be jostled around by incoming enemy sprites. The Chipmunk-based physics work, but I need some way to track the rotation of the sprite after a ...
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87 views

rotating sprite with quaternion in scenegraph

I have been trying to set up a scenegraph in XNA, which I then use to draw sprites in the correct places. It uses matrix transformations to accomplish this. So far, I got position and scale working ...
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36 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 ...
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35 views

How to find optimal perpendicular axis of rotation vector to draw arrows?

I am drawing lines on the screen. Each line has a point (x,y,z) and a direction (u,v,w). I want to draw arrow heads on these lines, like two lines that start from (x,y,z) and leave at a 15 degree ...
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85 views

GLM Rotating Combining Multiple Quaternions?

I have a camera which I want to control with my mouse. I want the mouse to control the pitch and yaw of the camera but not the roll. To avoid loss of significance, I am storing the quaternions for ...
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3answers
159 views

OpenGL: glRotatef cause performance drop while rotating -x and -y

I have made a rotating cube and I got some performance drops while using two glRotatef calls. So basically this code is giving me 80FPS: //code 1 GLrotate_x += 0.4f; GLrotate_y += 0.4f; ...
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1answer
250 views

How can I restrict the rotation of an object to a subset of axes using quaternions?

I've got a question about quaternions in my WebGL application. How can I rotate an object only around two axes? For example, how can I exclude/nullify rotation about the Y axis? The problem is that ...
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1answer
709 views

Unity objects not rotating around pivot point

Suddenly, for some reason, objects in the unity editor started rotating around their center of gravity (at least that's what I think is going on) instead of their pivot point. I tried placing the ...
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1answer
299 views

How to translate swipe gestures into rotations?

I am making a snake game. I want to rotate my snake in the direction specified by swiping on the screen, the directions are limited to orthogonals (90 degree increments). It's an android game. Can ...
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1answer
728 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 ...
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1answer
139 views

libgdx get rotated sprite coords points

I would like to get the position of each edge of a sprite when he has been rotated. I have no idea how to do it, I made a image to explain it. I would like to get the X and Y position of each Red ...
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1answer
150 views

JavaScript: Rotating a canvas around its center for a 2D sidescroller

I've been making a 2D sidescrolling game using JavaScript and HTML. The game is set in space, where the player character can fly around (Up, Down, Left and Right keys) and rotate the world around him ...
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0answers
87 views

Rotating SpriteBatch clockwise [closed]

I have developed a 2D game that looks great on the Android. Now I want to make it cross-platform. For this I need to literally rotate everything when it is on desktop. I tried to do that by rotating ...
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1answer
57 views

Rotating image around a given point

Im trying to simulate shadows in a 2d RPG, So far I can make the shadows but i cant blit them properly, Im trying to rotate them according to where the "sun" is (just a position) I have looked at ...
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0answers
31 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: ...
4
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1answer
266 views

How do I make a cube move by rolling?

I am learning jMonkeyEngine by making some small games with it. I have a simple rectangular cube that I want the player to be able to roll around the game world. When he presses the arrow keys, the ...
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1answer
755 views

OpenGL ES object rotation around z axis

I have an object on my screen which is presented rotated and panned, But i have 2 problems regarding the z axis rotations. It's a bit tricky to explain so i uploaded 2 videos to describe each problem. ...
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1answer
198 views

Bounding Box in Monogame for mouse picking

Hello guys so I'm implementing this mouse manager to be able to pick up objects. My application uses mainly textured quads in 3d space. I'm using bounding boxes in monogame to do so, however my ...
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1answer
450 views

How do I determine the look-at vector of a free-look camera?

I'm trying to create a free-look camera with DirectX 10. I've figured out how to get the directions for forward and back and left to right. However, I don't know how to rotate the look-at vector of ...
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313 views

Andengine Rotate Wheel with fast acceleration

I have a Wheel sprite and i am rotating it using Physics RevoluteJointDef. Its rotating. But problem is how i can make wheel to start moving fast. It took the speed after sometime like real. // ...
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221 views

Spin wheel with gesture in Andengine

I want to implement Fortune wheel in Andengine. The wheel would start spinning based on the speed of a finger fling. Then it would stop slowly like real Fortune wheel. What I am able to do now is to ...
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0answers
21 views

How do I scale and rotate around different points in Libgdx? [duplicate]

I'm using a SpriteBatcher to rotate and scale a TextureRegion in libGDX. I'd like to rotate the texture around an origin outside of the region, but have the texture scaled around the region's center. ...
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1answer
66 views

How to spin an object on its own axis?

I'm trying to spin up my own 3D vector graphics engine, so I'd like to do this without an existing library. And I don't seem to be able to find the math for the correct approach in rotating an object ...
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1answer
550 views

How to get plane rotation by known normal vector

I have a FPP quaternion Camera and Plane with known normal vector. I want to find the orientation of this Plane so I can replace it to the Camera orientation to put the camera forward vector to a ...
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4answers
171 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 ...
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0answers
126 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() ...
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1answer
46 views

Find out which way to rotate based on current rotation and final rotation [duplicate]

I have one object that I want to rotate to a certain angle with 'smooth' rotation. I looked up on how to solve that and I came up with this: enter image description here But how do I know in what ...
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1answer
365 views

Rotating a GameObject around its center

I'm trying to rotate a GameObject that consists of several cubes around its center of gravity on an axis. When using transform.Rotate(), it rotates around its pivot point (as shown in picture 1) and ...