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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5
votes
2answers
489 views

Is a dynamic enviroment map using pincushion curvilinear perspective projection possible?

I'm wondering if it is possible to generate a dynamic spherical environment map using a single frame render using a pincushion curvilinear perspective projection matrix (phew, that's a mouthful)? ...
4
votes
2answers
382 views

How can I manually construct a right-handed orthographic projection matrix?

I need the formula to create a orthographic projection matrix. I am using GLM math libary and DirectX11. The reason I cannot use GLM to create it is because the NDC spaces are different between DX11 ...
1
vote
0answers
197 views

How should matrix-based Parallax Scrolling work?

The question is at the end, as it requires a bit of context. I'm not sure if my understanding, my code, or LibGDX's ParallaxCamera is wrong. LibGDX's ParallaxCamera uses Matrix4s to achieve a ...
1
vote
1answer
82 views

How do I combine matrix transformation with non-uniform screen scaling in Flash?

I'm using a Flash transformation matrix for affine transformation. I have a rectangular image being rotated and scaled (in 2D). There are two sets of scaling variables, ScreenScaleX and ScreenScaleY, ...
0
votes
1answer
119 views

Find world matrix

I'm making my first 3D-game with XNA (MonoGame) and have come to a point where I wish to add a crosshair for the player. To do this I need the on-screen coordinates of the location where my fighter ...
2
votes
1answer
158 views

What types of matrices are needed for game and graphics programming?

I am writing a 3D math library for general game development and want to know what type of Matrix classes I should include. Is just a 4x4 matrix enough, or must I provide 3x4 and dedicated rotational ...
0
votes
1answer
296 views

How are 2D transformation matrices applied to their targets?

I understand mathematically how transformation matrices work, in that a transformation matrix multiplied by a vector results in a new vector, and we use the matrices for rotation, translation, etc. I ...
0
votes
1answer
120 views

Blender animation to XNA distortion bug

I followed the instructions on the following video: http://www.youtube.com/watch?v=SissgQ0IXvk I'm using XNA 4.0 and Blender 2.69 I export the model with animation to a .FBX file. The animation is ...
3
votes
2answers
297 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 ...
1
vote
1answer
63 views

How can I transform a Point2f with a matrix on Android?

I'm developing for Android and I'm using the android.renderscript.Matrix3f class to do some calculations. What I need to do now is to now is to do something like mat.tranform(pointIn, pointOut); So ...
1
vote
1answer
81 views

Matrix transformation

I have to find components of a matrix for 3D transformation. I have a first system in which transformations are made by multiplying: M1 = Scale x Rotation x Translation. I want to have the same ...
-3
votes
1answer
68 views

projection and matrices [closed]

Many games do just fine with two projections, that can be represented by a matrix (orthographic and linear perspective). But what about projections that can't be represented by a matrix? Can you ...
0
votes
1answer
136 views

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) ...
1
vote
1answer
387 views

How do I create a camera?

I am trying to create a generic camera class for a game engine, which works for different types of cameras (Orbital, GDoF, FPS), but I have no idea how to go about it. I have read about quaternions ...
1
vote
1answer
110 views

projection / view matrix: the object is bigger than it should and depth does not affect vertices [closed]

I'm currently trying to write a C 3D software rendering engine from scratch just for fun and to have an insight on what OpenGL does behind the scene and what 90's programmers had to do on DOS. I have ...
4
votes
3answers
560 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 ...
1
vote
1answer
3k views

OpenGL - Calculating camera view matrix

Problem I am calculating the model, view and projection matrices independently to be used in my shader as follows: gl_Position = projection * view * model * vec4(in_Position, 1.0); When I try to ...
1
vote
2answers
560 views

Drawing cube in SharpDX, wrong perspective

I want to draw a cube. This is what i currently have: As you can see, the perspective is VERY wrong. The the size in the z-direction is too small and the difference between the front and back size ...
3
votes
1answer
315 views

How to achieve cavalier projection using OpenGL fixed pipeline?

I want to make a quick demo program showing a cube, or a user loaded model, rotating in screen rendered with one of three projections: perspective, isometric and cavalier. Using the fixed pipeline, ...
4
votes
1answer
358 views

What are the performance and size tradeoffs of Eigen::Transform versus Eigen::Matrix4f?

We finished migrating from DirectXMath to the Eigen math libraries for our 3D-Game Engine last week for portability reasons. After implementing transformations with matrices as we know them, we found ...
3
votes
3answers
920 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 ...
2
votes
1answer
609 views

How do I check why is no output on screen?

I'm using OpenGL 3.3+, and I'm trying to create an orthographic projection to draw on screen. I have the model data in a buffer: X Y 0, 0 50, 100 100, 0 And I create my Model-View-Projection ...
0
votes
1answer
84 views

Scaling/Rotating triangle

I have a Triangle class and a list of triangles representing my 3D model shape. When I update the position, the rotation or the scale of my model, I also want my triangles list to be updated. I ...
0
votes
2answers
2k views

GLSL: can i use matrix transformation functions in vertex shader?

I have a working OpenGL code where i render a terrain with some trees. I am doing all the matrix mathematics on the client side. Because of which the frame rate of my app is very low, around 25-30 ...
5
votes
1answer
434 views

apply non-hierarchial transforms to hierarchial skeleton?

I use Blender3D, but the answer might not API-exclusive. I have some matrices I need to assign to PoseBones. The resulting pose looks fine when there is no bone hierarchy (parenting) and messed up ...
2
votes
1answer
105 views

Issues with 2D Body/Limb system [closed]

In my game I have programmed Body and Limb classes. The Body is guaranteed to have an origin in the center of its sprite. The Body class has a List of children Limbs, each with their own offset. Every ...
1
vote
2answers
63 views

Copying rotation between matrices

I have a transformed Matrix A and an another transformed Matrix B. How can I COPY the rotation of Matrix B to Matrix A?
1
vote
1answer
304 views

How to rotate vertices of 2D shape using a transform matrix?

I am making a top-down 2D game and am currently working on implementing improved collision using SAT. I programmed a Shape class with a Vector2 center that is its position in world space. On top of ...
2
votes
2answers
274 views

Frustum culling based on MVP matrix?

Tutorials on the internet usually say to extract plane data from MVP (model view projection) matrix (or VP?) and then test the bouding volume against each of the frustum planes. I've thought of a ...
1
vote
2answers
704 views

What dimensions should you use for a perspective projection frustum?

What dimensions should you use for a perspective projection frustum? Initially I created a perspective matrix based on the width and height of the screen, with a calculated zNear value based on a ...
2
votes
2answers
164 views

How to use camera transformation without depending on (1,-1) scale during spriteBatch.draw()

I am creating a 2D platformer type game in XNA. I currently have a camera object, with a position/rotation/zoomlevel that I use to generate a transformation matrix to pass to SpriteBatch.Begin(). ...
0
votes
0answers
41 views

XNA - Link between Create Rotations matrices

A friend of mine have been coding some rotations on my XNA project, but the order of the matrices rotation are not good. Some are of form : Matrix.CreateRotationZ(1.21f) * ...
0
votes
3answers
284 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; ...
1
vote
1answer
816 views

Converting 3 axis vectors to a rotation matrix [closed]

I am trying to get a rotation matrix (in 3dsmax) from 3 vectors that form an axis (all 3 vectors are aligned by 90 degrees each other) Somewhere I read that I could build a rotation matrix just by ...
0
votes
0answers
81 views

Matrix Translate Camera has some sort of spiky movement

public class Camera2D { private Vector2 _position; protected float _viewportHeight; protected float _viewportWidth; public Vector2 ScreenCenter; protected Being _unit; // the sprite camera is ...
0
votes
1answer
277 views

Distorted LookAt When Looking Up or Down?

I have a weird problem and I have no idea what's going on with it. Recently started doing some OpenGL programming, going pretty well, hit some rough spots but worked my way through them and otherwise ...
2
votes
1answer
656 views

The correct way to transform a ray with a matrix?

Playing with XNA Triangle Picking Sample I found out that it does not work well if you scale the world matrix of the objects you want to pick. When I dug into the implementation I found this comment ...
0
votes
1answer
540 views

First person camera world matrix issue (in THREE.js and webGL)

I'm trying to create a Portal-like effect in webGL using THREE.js. I have two scenes connected by a pair of portals. The view of the 2nd scene in rendered inside the 1st portal using stencils and ...
2
votes
2answers
42 views

Derive direction in which a spot light emites its light from a projection matrix

First of all, sorry if my question sounds too basic or even makes no sense. I'm new with game development I'm working with HPL1Engine, specifically, the lights parts. I need to know the direction in ...
0
votes
1answer
827 views

XNA 2D Camera, zoom into player

My 2D camera follows the character fine without any zooming. However, when I tried adding a zoom feature using the Matrix.CreateScale(), the camera no longer follows the character properly. public ...
2
votes
1answer
112 views

Minimal Projection Matrix

i hope you can help me. I'm currently stuck at the creation process for projection matrices used by shadow maps. The problem is the following: I got the spot/directional light ...
0
votes
1answer
940 views

Screen space decals, converting world to decal space

I'm trying to do screen space deferred decals following the presentation made by Pope Kim about SSDs in WH40K: Space Marine (link). I've gotten to the point where I can render a decal if the bounding ...
0
votes
0answers
64 views

“Blinking” graphical bug when rotating shadow matrix

So, we have implemented Krypton shadows into our code for our 2D game, and it's working beautifully. Only issue is that we're running into a bizarre graphical bug when rotating the shadows with the ...
6
votes
0answers
337 views

Rotation pitch/yaw reverse problems when picking a tile (2.5D) [closed]

Set-up: 3D world, isometric sprite rendering (4 fixed angles). This transform matrix is used as camera: _transform = Matrix.CreateRotationZ(Roll) * ...
0
votes
3answers
397 views

How can I properly rotate a 2D vector in the “flipped” XNA client space?

In my 2d XNA game, because SpriteBatch treats world space as client space and has positive Y axis down and negative up, I've built my game's world space with that coordinate system too. However, I've ...
2
votes
1answer
204 views

Finding out the “width” and “height” of my screen after projection added

In a 2d game, doing collisions with the edges of your screen is easy. Your textures are a 1:1 mapping of your screen resolution because your verities are too.. if your x position is > than ( screen ...
0
votes
1answer
2k views

Trouble with Collada bones

I have a Collada file with a rigged mesh. I've read the node tags in the library_visual_scenes tag and extracted the matrix for each node and stored everything in a hierarchical bone structure. My ...
1
vote
3answers
3k views

Replace glTranslatef and glRotatef with matrixes

I'm not an opengl expert, and, as a novice, I prefer to practice a little bit with the old opengl just to be sure to understand correctly the basic concept of computer graphics before deal with ...
2
votes
2answers
195 views

Why translation uses multiplication and not addition? [closed]

To translate an object from (x, y, z) to (a + x, b + y, c + z) it's done using: OK, that's cool, but why would we multiply in the first place when we can add the two matrices directly as: ...
0
votes
1answer
147 views

How can I adjust the UVs of my quad so my texture isn't flipped?

My sprite geometry is reversed using matrix so that it is in the XZ plane. This results in the image used for the sprite to also be reversed, which I don't want: (source : ...