A 2D array of numbers, symbols or expressions, arranged in rows and columns. Each row must have the same number of columns. The numbers, symbols or expressions themselves are called elements or entries.

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21 views

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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1answer
56 views

Convert transform from world to local space

I have a hierarchical node system. Given a world space transform, I need to obtain the transform for a specific node in local space. My Node class has the following method. public void ...
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1answer
40 views

Mode 7 in xna/monogame

I want achieve a view like Mode 7 from snes games where the closer textures get stretched out more and more far away textures look smaller. Something like this: What I have in my project at the ...
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1answer
356 views

libgdx - Box2d debug draw not correct

I have a problem where the bodies in my debug draw does not draw correctly, take a look: As you can see, there is some space between the dynamic body and the ground. I have checked the contact ...
2
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1answer
114 views

How can I approximate an “opening fan”-transformation?

Is there a way to—with matrices—transform something as if opening the image on a Japanese folding fan? Image from Wikimedia Commons. I'm at a loss of what to call it, so pointers towards avenues of ...
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2answers
51 views

Strange behavior with transformation matrix

I'm fairly new to transformation matrices. I'm using them to translate and rotate nodes and their child nodes. The following code works when applied once, but shows strange behavior when applied many ...
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2answers
1k 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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2answers
89 views

How to rotate camera using mouse?

I'm looking for a basic example of rotating camera using the mouse. the only problem is I'm not sure of how to rotating the camera around it target. should i do this by an algorithm or is there a ...
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1answer
165 views

Java OpenGL Perspective matrix not working

I'm trying to render a simple triangle with OpenGL in Java using LWJGL3. Everything is working great, but the projection matrix (perspective) is not working. In C++ I just used to apply the ...
2
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1answer
712 views

importing animations in Blender, weird rotations/locations

This is for the Blender 2.6 API. There are two problems: 1. When I import a single animation frame from my animation file to Blender, all bones look fine. But when I import multiple (all of the ...
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1answer
93 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 ...
2
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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
51 views

Rotating a 4D matrix about the Y axis with an X-Z vector

I should mention that I'm pretty new to Matrices and will probably need a layman's answer to my question. I have a 4D matrix which represents the rotation of an object in 3D space. I have a ...
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2answers
73 views

Rotation, what is the Matrix?

From a previous question, thank you very much by the way, but what on earth is the Matrix of? I'm very new to Mono/XNA and finding any meaningful documentation is practically impossible. point = ...
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1answer
38 views

Recap on how a camera works in 3d Space?

This may be marked as a duplicate, but I have been trouble thinking about a camera. I understand that there is a "camera transform," or view matrix. However, this is multiplied with every vertex in ...
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0answers
17 views

Rotate object from an origin using a transformation matrix

I'm making a project in lib GDX and I want to rotate an object by changing the transform matrix of the sprite batch to one that rotates an object rendered on screen a given number of degrees from a ...
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1answer
86 views

Rotate heading relative to agent's local space

I'm having a little trouble translating a point in my game's world space to an object's local space. I have a cannon in my game with a normalized heading vector that's always supposed to point in the ...
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2answers
977 views

How to do directional per fragment lighting in world space?

I am attempting to create a GLSL shader for simple, per-fragment directional light. So far, after following many tutorials, I have continually ran into the issue: my light is specified in world ...
4
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1answer
84 views

Do matrix manipulations for 3D graphics ever produce singular matrices?

A singular matrix is a matrix that cannot be inverted. The vecmath library, for example, throws a SingularMatrixException if you try to invert a singular matrix. I think I understand what singular ...
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0answers
10 views

Collision Hull not Transformed Correctly

My collision hulls aren't aligned after my "engine" digests them. I used Spine to create my content. So here is the hierarchical model of my bones. Where Root, LoadGame, NewGame, QuitGame, and ...
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1answer
44 views

What is more efficient: Using matrix translation to move a character, or using a vector/scalar?

In 2D or 3D, matrix transformations are used for rotation, scaling, and sheering. However, when it comes to movement, should I go out of my way to use and implement scalar/vector movement, or just ...
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1answer
44 views

Terminology for the way Transformation Matrix Data is treated

I recently asked a question at math stack exchange and realize a similar questions is more suited for this forum, but the original is here: ...
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0answers
87 views

OpenGL model transforms wrong on AMD GPU

I've been writing a program that uses OpenGL to display some simple 3D models (rays, cuboids, spheres and simple meshes). I am targeting the programmable pipeline in OpenGL 3.2. So far I have been ...
2
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1answer
389 views

What is the correct multiplication order for a 2D matrix?

I'm currently trying to create a camera and entity/model matrix for my 2D game similar to that of Unity3D. I've already tried to find answers to this question on stackoverflow/gamedev but i couldn't ...
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3answers
1k views

Should I use a world matrix?

Image reference for the question: (image from the CG tutorial) The D3D9 API got us used to world matrices. However, if you use world matrices, then you have to do an extra matrix multiply in the ...
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1answer
30 views

Last Row of the perspective projection matrix

Could you explain to me what is the purpose of -1 in the last row of the gl_projection matrix? And how it affects the perspective division step ?
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1answer
45 views

How can I get projected coordinates of vertex on screen

I want to check picking for faces and for that I need projected X Y coordinates of my vertexes in -1 to 1 range: For that I multiply my vertex array with matrices and then get projected triangle ...
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1answer
54 views

Cumulative transformation matrices for hierarchical object transformations

I'm having a small issue with my design for hierarchical 3D objects. I'll try to sum things up concisely. Every object has a vector3 for its position, scale, and rotation, as well as a std::vector of ...
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0answers
27 views

Tweening back from arbitrary 3D rotation in javascript

I'm using a 3D javascript library to rotate the vertex of a 3D object with a classic 3x3 matrix, to an arbitrary angle in the 3D space, as depicted in the image below. For example, a first ...
10
votes
6answers
7k 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 ...
2
votes
1answer
36 views

Change value of uniform for each VAO

I've heard from several sources that it's a better approach to pass the model matrix to a shader via a uniform rather than an attribute. I also know that the idea of a uniform is, that it has the ...
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1answer
59 views

Applying Transformation Matrices to VBOs in OpenGL

So I've recently tried to add Vertex Buffer Object Matrix transformation to an OpenGL engine I'm working on. I could go about this by applying the matrix to a copy of each vertex individually, but ...
0
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1answer
139 views

change position/orientation of a bone using assimp

I have been using assimp to import rigged models and animations. I followed this tutorial for skeletal animation and I have got it done properly. The part that I am trying to do now is to orient a ...
6
votes
1answer
285 views

How can I convert OBJ data into CSS3D transformations?

I want to convert the data in a 3D .obj file (vertices, normals, faces) to CSS3D (width, height, rotateX,Y,Z and/or similar transforms). I found a bunch of formulae and what-not, but 3D isn't my ...
4
votes
1answer
512 views

Tetris: 2D Rotation Matrix?

I'm creating a Tetris clone right now. I've got the tiles of tetromino stored as an std::array<tile, 4>. Each tile holds its (x,y) coordinates relative to the piece. For example, the t-block ...
4
votes
3answers
5k views

Inverting matrix in HLSL

I've got an object in HLSL and I'm using hardware instancing to render multiple copies. But I've come a bit of a cropper when it comes to the vertex normals. Currently I am not using normal mapping ...
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0answers
69 views

Matrix transform from one coordinate system to another

I have been beating my head against the wall for weeks on this and it is time I just break down and ask for help. I need to move a 3D camera from an in house system into Unreal 4. The two use ...
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0answers
31 views

Is it normal in skeletal animation to NOT consider the translation component in bone transform matrices?

I'm using assimp to load a model, and DirectX11 and DirectX ToolKit to render it. In the document of DirectXTK's IEffectSkinning, it says: As an optimization, SkinnedEffect and DGSLEffect assume ...
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1answer
92 views

Why would this scaling matrix have no effect?

To draw a simple model using the DirectXTk, I'm doing the following. It all works perfectly, draws correct, and so on. Except changing the scaling factor makes NO difference, and I can't figure out ...
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votes
1answer
212 views

THREE.JS: why is the rotation only applied on the last axis used?

my function: function rotateAroundWorldAxis2(object, radians1, radians2) { object.rotWorldMatrix.makeRotationX(radians1).makeRotationZ(radians2); // object.rotWorldMatrix; ...
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0answers
57 views

Scaling geometry in an orthographic view

I'm having trouble understanding the results I'm getting from some of my matrix transformations. I've got an orthographic projection, and am drawing 2D circles on the screen. There is a camera matrix, ...
1
vote
3answers
68 views

How much to roll Z to make horizon level

I've got a flying camera with some arbitrary rotation. (It also has a translation, but that's not important.) It's flying along its local Z axis, traveling in some direction over the ground with ...
4
votes
1answer
295 views

Projecting onto different size screens by cropping

I am building a phone application which will display a shape on screen. The shape should look the same on different screen sizes. I Decided the best way to do this is to show more of the background on ...
2
votes
1answer
252 views

Rotation going wrong

I'm calculating matrices by hand. Translations are fine: void Translate (float x, float y, float z, float[4][4] m) { Identity (m); m[3][0] = x; m[3][1] = y; m[3][2] = z; } If ...
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1answer
53 views

How to transform a matrix's local space position into another's local space

When looking at an example to learn how to do per pixel collision, I came across this: // Calculate a matrix which transforms from A's local space into // world space and then into B's local space ...
3
votes
2answers
4k views

calculate new vertex position given a transform matrix?

How can I get the new position of my vertex given a 4x4 transform matrix or simply 9 floats (positionX, positionY, positionZ, rotationH, rotationP, rotationR, scaleX, scaleY, scaleZ)? Usually I can ...
0
votes
1answer
128 views

XNA 2D rotation Matrix offset/origin

I'm currently struggling with finding the offset for my original camera translation after I have applied a rotation for it. transform = Matrix.CreateScale(new Vector3(1, 0.75f, 1)) ...
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1answer
54 views

Camera (pole cam) implementation problem

In my project I have simple scene graph to render whole scene and Bullet physics SDK to provide physics simulation. Each rendered object is represented as scene node. Camera always has target and ...
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2answers
85 views

Problematic cameraposition (Eye = (0,0,0), at=(0,-2,0) and up = (0,1,0))?

I am taking a course in computergraphics and we talk a lot about OpenGL and the math you need to do everything OpenGL does "by hand". A Question which was asked in an old exam (I am preparing at the ...
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0answers
44 views

Rotation matrix is being inconsistent with pitch and roll

I'm calculating the rotation matrix for a turret when it's at an angle in Javascript. I have XYZ co-ords for the turret and target with X being 90 degrees right, Y being straight ahead and Z being ...