GLM is a C++ math library based on the GLSL language.

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OpenGL Arc-Ball Camera Yaw Pitch GLM::Rotate

I'm currently working on a small Voxel-Editor Project. In the editor, I plan on using an Arc-Ball camera which rotate around the model. My camera is currently working but in an odd way. I can't seem ...
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C++ Opengl rotation Rotating vector before transform still rotates around 0,0,0… In world position [duplicate]

So how should I get this to work in local position? (Ie, moving to 4,0,4 and rotating around 4,0,4 . (x,y,z)) Here is where I add models / verticies: glm::vec4 pos = glm::vec4(1.0); glm::mat4 ...
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Failed to understand how to use glm::unProject (OpenGL 4.3)

Situation: I use OpenGL 4.3, FreeGLUT 3.0, and GLM library. Let say i have a simple 2D object (a ball) and it moves accordingly to the simple equations: x = x_0 + v_0 * t * cosf(alpha); y = y_0 + ...
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67 views

How should I rotate vertices around the origin on the CPU?

I have tried using glm::rotate and such. glm::translate works fine, but rotate doesn't work (if I rotate before/after a translation). Here is my current setup: glm::vec4 Off = glm::vec4(0, 0, 0, 1); ...
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1answer
41 views

C++ Opengl transforming a glm::vec4 with a glm::mat4

Its easy enough doing it on the gpu via GLSL, but how would I do this in c++? When I try it gives me an error telling me I cant cast a glm::mat4 to float, Which makes sense, but how should I do it? ...
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1answer
45 views

Converting normalized device coordinates to world space coordinates flipping my sprites

I'm trying to convert my game's camera system to use world space coordinates rather than OpenGL's default normalized device coordinates, however in doing so my sprites are being rendered improperly as ...
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1answer
40 views

Shaders wont bind to the uniform block

I'm having an issue with interface block binding. Example shader: const char* vertexShader = "#version 330 core\n" "uniform globalMatrices" "{" " mat4 ...
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3answers
47 views

Storing component vectors to avoid matrix and quaternion inaccuracies?

I read that I "should really be storing the component vectors (rotation, translation, scale) in addition to the quaternion and matrix forms." The reason for this is that, over time, compound numerical ...
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1answer
80 views

Make Camera Look at point using a World transformation matrix?

Variants of this question might have been asked on this site, but none of the answers I found worked in my case. I am trying to make a Camera look at a point. The camera has a world transformation ...
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0answers
25 views

Formula for model matrix with mouse coordinates

I'm trying to create a simple OpenGL app where I can drag objects with the mouse. In its current state, I am able to do this, but the aspect ratio is off, so the object is moves faster or slower than ...
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1answer
92 views

Smooth matrix rotation

I have a coded a simple example for a matrix rotation. The example rotates a sphere around its center. The problem is that the rotation is not running perfectly smooth and I'm wondering why. Here is ...
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1answer
121 views

OpenGL 3.3+ Problem with ortho projection for UI/HUD

I have to a little bit of a problem with drawing HUD elements on top of my 3d world using a ortho projection. My 3D world keep getting render but there is nothing showing of my UI. I wrap the code ...
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1answer
92 views

Using glm to rotate the modelview matrix based on the cursor position

I am rendering a 3D model of an object, and I want the user to be able to rotate around that object by dragging the mouse. To do this, I want to use the cursor position to continually update the ...
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1answer
45 views

glm Z coordinates are flipped

I am trying to render a 3D model using OpenGL. And for the projection and transformation matrices, I am using glm. I've got my model on the screen and it works just like I intended it to; except one ...
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2answers
509 views

How to find the “up” direction of the view matrix, with GLM

Using OpenGL and the GLM matrix library, I want to translate my camera relative to the world coordinate system. This requires me to compute the necessary view matrix. To initialise the view matrix, I ...
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0answers
36 views

Quaternion camera in 3D space with Pitch and Yaw

I am having trouble implementing a quaternion camera that can fly freely in 3D space with only Pitch and Yaw rotations. It works fine except when you look up or down and then try to look left or ...
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1answer
92 views

issue with ray/physics collision detection

All, I am trying to pick object using ray collision and bullet physics I am initializing my projection and view matrix only once, here is the code projectionMatrix = glm::perspective(90.0f, 4.0f ...
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0answers
107 views

Transformed Vertices have wrong Z Axis

For quite some time I've been working on my open 3D game engine, to learn how this stuff works. You can see the full codebase relating to my problem here on GitHub. I'm using an OpenGL 3.3 Core ...
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2answers
1k views

How can I set up an intuitive perspective projection/view matrix combination in OpenGL, using GLM?

Could anyone help me set up an intuitive perspective camera matrix using OpenGL and the GLM library? By "intuitive" I mean that I want the camera to be looking at the middle of the screen down the -Z ...
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0answers
109 views

Frustum Culling is incorrect

I have checked the other posts on here, but haven't found a suitable answer. I'm trying to implement frustum culling using the Gribb-Hartmann technique, but am running into a strange issue where ...
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2answers
1k views

Rotating an object with quaternion

I have a question in regards to using quaternions for the rotation of my graphics object. I have a Transform class which has the following constructor with default parameters: Transform(const ...
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483 views

OpenGL - Arcball camera rotation

I'm implementing arcball camera rotation, whereby a camera is looking at a coordinate and rotates around it in the x-axis or the y-axis such that the camera is circulating around it; the y-axis will ...
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1answer
173 views

Directional lights (not) rotating with camera (opposite problem)

I am trying to implement a shader for directional lights correctly, but I am bit confused as to why it works when it shouldn't and vice versa. People usually encounter problem with lights changing ...
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2answers
986 views

Weird GLM perspective problems with my 2D Game

I am trying to create the graphics system of a 2D game using OpenGL 3.3. To help me in this task I am using the GLM math libraries. However I am having some trouble. When my objects (for now they ...
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1answer
2k views

glm direction vector rotation

I'm working on a flight simulator, but I'm stuck with my airplane orientation. I tried some things but noone worked correctly. This is what I have : To be able to move it and roll it around himself, ...
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1answer
505 views

Compute billboard rotation

I'm trying to compute a matrix to have object always facing the camera. For the moment, my result look pretty good, the problem is that my original billboard scale isn't preserved (Every billboard ...
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1answer
730 views

How to calculate directional light frustum from camera frustum

I'm playing around with OpenGL for a few weeks now. For the following screenshot I picked the glm::ortho values for my lightsource by trial and error. There are two directional light sources with ...
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2answers
352 views

GLM/OpenGL: How Can I Prevent Vector Magnitude From Increasing While Rotating Bones in Skeletal Rig?

ANSWER AT THE BOTTOM OF THIS QUESTION I have been reading tutorials, articles, questions on StackExchange and books all with the subject of skeletal rigging. I have boiled my program down to just the ...
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0answers
150 views

OpenGL/GLM Camera

I want to make a camera that can freely look and walk on X/Z plane and rotate 360 degrees. I'm using OpenGL and the lookAt function from the GLM library to create the view matrix. I've looked through ...
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1answer
1k views

OpenGL - have object follow mouse

I want to have an object follow around my mouse on the screen in OpenGL. (I am also using GLEW, GLFW, and GLM). The best idea I've come up with is: Get the coordinates within the window with ...
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1answer
186 views

Making particles accelerate toward a mouse point

I'm currently working on a particle simulation program that makes pixels move towards a mouse point continually accelerating, but i'm running into some math issues. Currently my particle will ...
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139 views

Bounding box center after transformation - want degree values for GUI

Similar to my previous question, I have a bounding box that I have transformed and scaled. Now, I want to get its center by doing this operation and store this value. bbCenter = glm::vec3(bbMin_x + ...
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255 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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1answer
1k views

How Extract Frustum Planes from Clip Coordinates?

I'm having some problems with my Frustum Culling and I want to debug it, so I'm trying to render it's planes, to see exatly the Frustum. But I'm using the Clip Coordinates to do the culling (like ...
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1answer
469 views

Build unity like Transform class [closed]

I am building a Unity-like Transform class. This is my header file: #include "Common.h" struct Transform { public: Transform(); void Translate(float x, float y, float z); ...
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1answer
1k views

Skeletal animation with Assimp and glm

I'm trying to implement skeletal animation using assimp and glm. Everything seems to work, except for rotations. This is the code I use when packing assimp data into my own engine's format. I THINK ...
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1answer
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problem using glm::lookAt and glm::perspective

I'm trying to change the code from the 22th tutorial at http://ogldev.atspace.co.uk/, using the GLM library, but the result seems wrong. The problem is shown in the below picture: While it should be: ...
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1answer
3k views

glm quaternion camera rotating on wrong axis

I'm trying to get my camera implemented with a glm::quat used to store the rotation. However, whenever I do circles with the mouse, the camera rotates along the axis I am viewing (i.e. I think it's ...
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1answer
376 views

Why do these quaterion multiplications produce different results?

I am trying to use quaterions to modify the camera direction vector. This code works perfectly: glm::quat temp1 = glm::normalize( glm::quat((GLfloat)( -Input1.MouseMove.x * mouse_sens * time_step), ...
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1answer
4k views

Combining rotation,scaling around a pivot with translation into a matrix

In short: I need to combine rotation (in the form of a quaternion), scaling around a pivot point along with translation into a transformation matrix. The long: I am trying to implement a proprietary ...
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115 views

Determining axis to rotate around

I'm trying to implement a free-look third person camera (using glm). I know that the general transformation is newCameraPosition = translate(lookatPoint) * rotation(angle,axis) * ...
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2answers
380 views

What ways are there for making vector types available in scripting?

I use Google V8 engine to embed Javascript into my game for scripting. As interface to my native code, I already registered some C++ functions to the scripting context. In the native code, I make ...
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2answers
9k views

Rotating an object when the center in not the origin - opengl

I'm beginning with GLSL and I learning the basic, I am using glm to do the matrix calculations at this point everthing ok,the problem is how I can move the origin to the center of my object, not the ...
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1answer
372 views

Trying to convert as3 Matrix to C++ glm matrix

I am trying to convert a library called DragonBones to C++ Opengl which allows you to use Flash based skeletal animation. I'm almost done but I am running into a problem. I am trying to transform the ...
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1answer
678 views

How can I remove the view and projection matrix from ray position to get only the ray model?

I've got a little problem with my picking module and I need your help. I have a method to project a ray from the camera to a fixed point when I click somewhere. The computed ray looks good, it go to ...
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1answer
101 views

Get the address of a matrix in GLM library

Is there a way to get the address of a matrix from a GLM matrix? I'm using opengl 4 and glm library though I can't seem to find anything, which might help.
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1answer
299 views

How to rotate camera around some point?

I have screen with dimensions: 800x600. The object that I want to rotate around is located at (400,300, -50) - center of the screen. Orthogonal projection: Near plan - 0.1f, far plane - 1000.0f left - ...
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1answer
762 views

Rotating and Translating a Node in Horde3D with Matrices and Quaternions

I have been trying to learn how to use the Horde3D rendering engine for the past couple of days, and so far I have managed to learn a decent amount and integrate Bullet Physics with it as well. My ...
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2answers
2k views

Texture mapping issue in my Wavefront *.obj parser

I wrote a simple *.obj parser reading read vertices, texcoords and normals. But when I draw a model the texture isn't mapped correctly. I have already tried uv.y = 1.0f - uv.y to get inverted Y axis ...
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1answer
1k views

Picking 3D with OpenGL ES 2

I'm trying to implement picking in my framework but I don't understand how I can do this. I'm working with: OpenGL ES 2. GLM mathematic library. What I have understand, picking can be made with ...