Transformation in game development is usually refers to linear algebra operations on points, vectors and matrices.

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2answers
90 views

Translating an object in the rotation direction

I am creating a graphical scene with OpenGL and SDL, and I'm running into a problem in regards to translating an object in its rotation direction. Each of the graphical objects in the scene has a ...
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1answer
403 views

How can I create a 2D camera with upscaling and translation?

I've computed a Viewport that is fair in size (a proper aspect ratio to the given device) and then I calculate my ScaleMatrix like so: scaleMatrix = Matrix.CreateScale( (float) ...
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0answers
81 views

How to work with edge Texture [duplicate]

Im not sure if i use the right terms, but im not able to find something to start with. Im trying to develop a little HTML5 game. I have a ground with a texture and now I want to make a surrounding ...
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3answers
381 views

Inverting matrix then decomposing gives different quaternion than decomposing then inverting the quat

I'm getting different signs when I convert a matrix to quaternion and invert that, versus when I invert a matrix and then get the quaternion from it: Quaternion a = Quaternion.Invert(getRotation(m)); ...
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3answers
2k views

In Maya how do I convert trans, rot, scale data to a 4 x 4 transformation matrix?

I have been given the following Maya camera data: trans X: 1.542 trans y: 3.319 trans z: -1.821 rot X: 117.882 rot Y: 2.189 rot Z: 154.074 scale X: 1 scale Y: 1 scale Z: 1 What is the ...
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2answers
50 views

Translating Objects in Worldspace

Given the worldspace coordinates of a collection of arbitrarily positioned objects, how do I translate them while preserving their relative placement? For instance, I have a table and a few bowls that ...
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1answer
10k views

How can I translate a game object towards a position?

I am instantiating my game objects (spheres) through scripts. I want my spheres to move from one location to another. but I don't know how to do this. Update is called once per frame. Is that what I ...
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1answer
181 views

Deformation of Sphere using Transformations

I have a graphic related question. I need to have a transformation matrix that I have no idea about what it is. The problem is to create right image from the right sphere. I created those images in ...
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1answer
45 views

How to compute the forward, up and right vectors from a single quaternion?

Given a quaternion float x, y, z, w; How does one the forward, up and right vector from a single quaternion? vec3 up; vec3 forward; vec3 right; quat_get_all_axis(&quat, &up, &forward, ...
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1answer
43 views

Camera world matrix to view matrix

I've been working on a game engine and I model every object in my scene graph as an "entity" this includes my camera. My camera therefore has a position and rotation in world space and at the moment ...
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2answers
326 views

How can I make EaselJS' skew behave like canvas'?

The skew property of a bitmap in EaselJS (given as angle) rotates the image such that it also flattens. I'd like to skew it without "squashing" it, as canvas does. JSFiddles, to demonstrate: Canvas ...
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1answer
125 views

How can I make an attached gameobject behave correctly on character flip?

I have a character that on start-up is equipped with another gameobject/prefab as a weapon, attaching it to a hand. void Start() { handFront = transform.Find ...
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1answer
65 views

changing coordinate system

I'm currently trying to transform a system by scaling it on x and y axis and have some uncertainty. I have the general concept that scaling works as such: My original box has corners at (0, 0) and ...
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1answer
330 views

Canvas isometric translations to integer coordinates

I'm creating a canvas based game with an isometric playing board. I use the following transformations to get my square tiles to render on the screen: 'applyViewportTransformation' : function() { ...
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2answers
2k views

Render rotated rectangle inside other rectangle bounds using Libgdx

I have this code to generate a red rectangle inside a grey rectangle: new Rectangle(grey_rectangle_position_x, Game.SCREEN_HEIGHT/2-Rectangle.height/2,0); This code makes the following: Now, I ...
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1answer
998 views

Translating local to global coordinates in ARToolkit / OpenGL

Ok, so I've tried reading over the other questions and something's just not clicking for me. I am working on an augmented reality application using ARToolkit, however it should just be straight ...
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1answer
117 views

How to constrain axis-angle rotation?

I have a problem where I'm performing an axis-angle rotation and am trying to constrain my rotations. Specifically I have a skeleton (model/mesh with rig, transforms are hierarchy parented to pelvis ...
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1answer
28 views

Error in plane transformation

I have a bunch of coplanar points, who sit on plane P. I want to translate the plane to Q with the points upon. Here is what I do: I take three points from P, say a, b, c. Their centroid is denoted ...
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1answer
73 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, ...
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1answer
70 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 ...
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2answers
110 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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1answer
279 views

How to project spherical coordinates to canvas

I have objects with coordinates in a spherical coordinate system (altitude alt and azmiuth az). I want to project those to my canvas with a given size (128 x 128 pixels²) and resolution (about 6 ...
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1answer
259 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 ...
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1answer
142 views

How to make child transforms honor parent origin

I'm working on a 2D transform system that has the following requirements: Transforms can have children Transforms have anchor points/origins that offset them Children should honor the parent's ...
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1answer
88 views

Picking problem with rotated view matrix

I have picking code that works, if my view matrix has no rotation (only translation). Now If I rotate my camera, picking goes to hell. I cant find whats wrong My code: ...
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1answer
244 views

How can shears/reflections/enlargements be represented by 4x4 matrices? [closed]

I understand that 4x4 matrices can represent transformations on a 3d point (represented as x, y, z, w) Eg, a translation is [1 0 0 0] [0 1 0 0] [0 0 1 0] [x y z 1] where x, y and z are the amount ...
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1answer
228 views

How to calculate the Screen Position of a bounding sphere/box?

Synopsis: What I have is an object rendered on the screen. I need to calculate the top-left / bottom-right of it's location on the screen in Screen Coordinates. Explanation: The object is ...
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1answer
183 views

Proper approach to handle transformation matrix and extract its components

Basically I have a Transformation component object with following structure(pseudo): TransformComponent{ Vec3 position; Vec3 rotation; //in euler angles Vec3 scale; Mat4 worldMatrix; ...
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1answer
225 views

SimpleOpenNI: Check if user hand is in specific area on image

Concerning our Microsoft Kinect project, we need some help. We control a robot with our movements tracked by the Kinect sensor. We display the depth image of the Kinect sensor on our screen, so we ...
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1answer
162 views

Orthogonal projection and world transform

I'm reading about projection matrix. Needs of perspective projection is obvious, but I'm not sure about orthogonal projection. Because orthogonal projection effect looks possible with only world ...
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1answer
520 views

Transform 3d viewport vector to 2d vector

I am playing around with 3d transformations and came along an issue. I have a 3d vector already within the viewport and need to transform it to a 2d vector. (let's say my screen is 10x10) Does that ...
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1answer
258 views

How do I draw shape distortion with a Texture2D in XNA?

Say I have a rectangular Texture2D object in XNA, and I draw it on the screen. How can I animate it so it slowly changes to a trapezoid shape, and then to a pentagon, etc. I have no idea what this ...
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0answers
46 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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0answers
40 views

How do I create a view matrix directly from a quaternion and a position vector?

Given a quaternionic camera such that: typedef struct { vector3 upReference; vector3 rightReference; vector3 forwardReference; vector3 position; quaternion orientation; ...
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1answer
506 views

2D Matrix Transformation (with a Player and Ground)

I have a simple game that I'm trying to do for learning purposes, but Matrices are a bit hard, especially in DirectX. I currently have a tilesystem that renders tiles at the screen and a character ...
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1answer
639 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
272 views

World to Pixel Transformation

My objects have a location in world coordinates (basically 1.0f is a meter). If I simply draw my objects using their world coordinates, each meter will correspond to a pixel. Obviously that's not what ...
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2answers
230 views

OpenGL: Transformations

I'm not sure if I correctly understand 3D transformations in OpenGL. Let's assume I'm using the typical matrix stack. It seems like you move the world X units over, drop in a bag of verts (a mesh) ...
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1answer
145 views

coordinate transformation

I have two coordinate systems, like so How can I transform a point on the one of the coordinate system to other ? Pxyz = M . Px'y'z' what is M ?
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1answer
296 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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2answers
253 views

Keep Mini map static after rotating / zooming with camera

Hi I am making a 2D game, where the Camera is able to rotate / zoom in or out on the camera focus (the player usually). However my game also contains a mini-map, and so far whenever I have to rotate ...
0
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1answer
104 views

Last Matrix operation ignored?

I have 2 methods, one to rotate my Quad and one to flip it (using scaleM), they are as follows: (Note, all values in these methods have been properly defined). If I call just one, they work as ...
0
votes
1answer
1k views

Interpolating a player between two 2D points?

I would like a player to be able to move in a direction smoothly, whilst sticking to a fixed grid. Much like in Pokemon, how the player can move, but when the key is pressed and released quickly, they ...
0
votes
1answer
741 views

Rotation of Rectangle along Y-axis transformed to parallelogram

After the rotation of a rectangular view along the Y-axis, about its center, transformed into parallelogram, how do I get the rotated parallelogram coordinates? By Y-axis, I mean perpendicular to the ...
0
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1answer
583 views

Optimizing hierarchical transform

I'm transforming objects in 3D space by transforming each vector with the object's 4x4 transform matrix. In order to achieve hierarchical transform, I transform the child by its own matrix, and then ...
0
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1answer
33 views

Inline-Building a World (SRT) Matrix

Currently, to construct a world matrix, I have the following code: return FromScale(scale) * rotation.RotMatrix * FromTranslation(translation); However, this is constructing three matrices, and ...
0
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2answers
124 views

Transform translation relative to world space

What is common algorithm for translating a transform matrix relative to world space axis? E.g. Matrix M is representing some local space. When I want to translate M relative to it's own local axis, I ...
0
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1answer
77 views

How to change Vectors due to change in it's dependent Base Vector?

PLOT : I have been developing a game where the player falls down on Y axis and the camera is a Top-Down view camera. The camera, player (main character in the game) movements etc. have all been ...
0
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2answers
391 views

3d vertex translated onto 2d viewport

I have a spherical world defined by simple trigonometric functions to create triangles that are relatively similar in size and shape throughout. What I want to be able to do is use mouse input to ...
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1answer
45 views

How to force a translation to go through an exact point?

I have a camera object with a script that will whether translate it with a set speed, or stop it. I also have 7 "checkpoints", where there are 7 different quads, who will stop the camera whenever the ...