0
votes
0answers
72 views

3d game math problem

i'm very much new to 3d math operations. I know how to rotate 3d points certain degrees arbitrarily by any axis but we were given a strange problem to think on. I'll spare using actual numbers on ...
1
vote
1answer
132 views

Mouse click movement

I need to make realistic human movement (3D) using mouse click. Get mouse click point using Raycast. Smoothly Slerp to LookRotation. Move transform.forward. Everything works fine, except I have ...
0
votes
2answers
86 views

Quaternion Rotation Help

So I'm making a little engine with DirectX 11 and C++. (Some other help from other API's as well) DirectX has this function XMMatrixRotationQuaternion(XMVECTOR quaternion). I know nothing about this ...
0
votes
0answers
62 views

X, Y, Z rotation around camera

I'm making a 3d orthogonal-projected, game using painters' algorithm in java. I'm able to rotate the objects with incremental rotations (e.g. rotate all objects 10 degrees) using affine ...
0
votes
2answers
118 views

Why do we say things are rotated around the z-axis in a space graph?

I've embarked on a journey of game development. I need to learn lots of 3D terminology, since I want to make 3D games. I learned that X is to the right, Y is up, and Z is towards you. Then why when a ...
1
vote
3answers
225 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
290 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 ...
0
votes
3answers
147 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; ...
2
votes
1answer
708 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 ...
0
votes
1answer
434 views

LWJGL Camera Rotation Issues

I am quite new to LWJGL and OpenGL and I am trying to create an FPS camera. I had no problem with 2D stuff, so I decided to step things up and try and make some things in 3D. I have this 3D camera ...
4
votes
5answers
1k views

How to rotate an object around world aligned axes?

I have a Vector3 which has an euler angle for each axis. Usually, when I want to create a rotation matrix I will use functions such as D3DXMatrixRotationX passing the respective angle from my ...
0
votes
1answer
246 views

(XNA) 3D Model Rotation Angles

I'm currently in the process of making a 3d "semi" top down game, the camera comes in at a very high angle near 90 to show off the 3d models. I have a main character which can move in 4 axis (up, ...
0
votes
0answers
53 views

3D Box Collision Data Import

I'm trying to implement a collision system using oriented bounding boxes, using a center for the box, it's extents as a 3D Vector and a rotation matrix, which is all stuff I picked up online and seem ...
0
votes
0answers
242 views

JavaScript 3D space ship rotation

I am working with a fairly low-level JavaScript 3D API (not Three.js) which uses euler angles for rotation. In most cases, euler angles work quite well for doing things like aligning buildings, ...
1
vote
1answer
474 views

Correct rotation with Quaternion

I have some problems with a rotating marble. I've tried it with Matrix.CreateFromYawPitchRoll and Matrix.CreateRotation but there were some problems, I think it's due to the Gimbal lock effect. So, ...
1
vote
0answers
97 views

Rotate view matrix based on touch coordinates

I'm working on an Android game where I need to rotate the camera around the origin based on the user dragging their finger. My view matrix has initial position of sitting on the negative z and facing ...
1
vote
1answer
289 views

Rubik's cube array rotation

I'm about to make a 3D Rubik's cube based game in Flash AS3 and Away3d. I don't really know how to manage the 2D arrays of the Rubik's cube. For example, how do I rotate the corresponding arrays if ...
3
votes
1answer
249 views

Matrix represents same rotation with different euler angles

I have Transform component storing it's rotation as Quaternion. Transform has set/getEulerAngles (rotation order oy, ox, oz). I want to rotate object in any direction but while testing I get ...
0
votes
2answers
144 views

How to rotate one object around another moving object in 3-d?

i was wondering if anyone could give me some advice on how to rotate one object around another moving object. After a bit of googling i found some code on another website that worked perfectly but it ...
2
votes
1answer
242 views

Moving an object toward another object on sphere knowing their quaternions

I have a sphere centered in world origin. On the sphere surface I have two objects and I know their quaternions (rotation around sphere). Currently my movement works on Vector2 inputs (cannot change ...
2
votes
0answers
126 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 ...
1
vote
1answer
190 views

how to move the camera behind a model with the same angle? in XNA

I'm having difficulty moving my camera behind an object in a 3D world. I'd like to have two view modes: for fps (first person). external view behind the character (third person). I've searched the ...
7
votes
3answers
772 views

Routes on a sphere surface - Find geodesic?

I'm working with some friends on a browser based game where people can move on a 2D map. It's been almost 7 years and still people play this game so we are thinking of a way to give them something ...
3
votes
2answers
452 views

3D rotation matrices deform object while rotating

I'm writing a small 3D renderer (using an orthographic projection right now). I've run into some trouble with my 3D rotation matrices. They seem to squeeze my 3D object (a box primitive) at certain ...
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
2answers
4k 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 = ...
8
votes
2answers
353 views

Render 3d object to 2d surface (embedded system)

i am working on an embedded system of a sort, and in some free time i would like to test its drawing capabilities. System in question is ARM Cortex M3 microcontroller attached to EasyMX Stellaris ...
4
votes
1answer
2k views

Moving a rotated model in XNA

This seems like a simple problem with an equally simple solution that is invisible to me. I have a model that spawns at the origin and looks at my player model wherever it goes. I would like it to ...
2
votes
3answers
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 ...
5
votes
1answer
7k views

How to calculate a 3x3 rotation matrix from 2 direction vectors?

I've got 2 direction vectors, for the X axis and the Y axis of the object. How do I calculate the rotation matrix of the object using these?
2
votes
3answers
525 views

How should I model exact 90-degree rotations in 3D?

I'm familiar with quaternions... have used them in the past to model arbitrary rotations in 3D, as for a plane flying around with full pitch/yaw/roll freedom. Works great. Now I'm working on a 3D ...
2
votes
1answer
6k views

Rotating an object in OpenGL about it's centre

Im writing a game for which, one of the models are loaded from an .obj file. It's a model of a plane, and I want to rotate the propeller. The object file is broken into groups, and the propeller is ...
9
votes
3answers
660 views

Can I use quaternions to control an helicopter?

I'm trying to make a simplified helicopter (for the moment, it's a cube) simulation in 3D and I'm having some problems with rotation. An helicopter can rotate along the three axes : rotate on itself ...
1
vote
2answers
472 views

Rotating coordinate system

Lets say that you want to rotate simple cube around fixed point in center. Is it possible to use such coordinate system, that you need to use only sine and cosine in order to rotate? I have done ...