Numeric representation of the location of an entity in the game space. There are multiple forms of coordinate systems to cater to a variety of methods to map position.

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1answer
49 views

drawing line using angle

code below make enemy move towards player. //Calculate Distance formula double xDiff = player.x - enemy.x; double yDiff = player.y - enemy.y; double dist = Math.sqrt(xDiff * xDiff + ...
0
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1answer
276 views

isometric coordinates issue: (0,0) and (5,5) are flipped?

I am having an issue with the isometric coordinates. When I enter the coordinates (5,5), the character should be at the bottom corner of the tile, but it is at the top corner, (5,5) and (0,0) look ...
1
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1answer
205 views

What is the purpose of inertial space and what are its uses?

I'm currently reading about left-handed and right-handed coordinate systems when working with 3D and it's all very fascinating. These systems are made up of world space, object space, and inertial ...
2
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1answer
173 views

Is it bad-practice using left-handed coordinate system in OpenGL eye-space?

In the engine I am currently programming I want to use a left-handed coordinate system for eye-space instead of the glFrustum standard right-handed one. Is that in anyway considered bad practice?
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3answers
3k views

Spherical coordinate from cartesian coordinate

I am implementing a type for Ogre 3D rendering engine to provide spherical coordinates. So far everything is working fine, until I try to build spherical coordinates from a cartesian vector. Here is ...
2
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2answers
168 views

What's the rationale for different coordinates systems?

Could someone explain to me why Blender and other 3D modeling apps switch axes? If I export model with Blender, then exporters do following things for the same model: The 3DS format applies this ...
0
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1answer
106 views

How can I solve for the game's world coordinates?

I've used 3DReaperDX to get a obj file, the header information are shown as follows: #AR=2.00606, FOV=45.09583(height), Xscale:0.83290, Yscale:0.41519, Zscale:1.0 ...
0
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2answers
127 views

Need to know the origin and coordinates for 2d texture and 2d/3d vertices in webgl

Long story short, I know my coordinates are off and I believe my indices might be off. I'm trying to render a simple 2d rectangle with a texture in webgl here's the code I have for the vbo/ibo: ...
0
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1answer
122 views

How can I plot points and generate a list of coordinates?

I'm trying to make a game which involves drawing a map. I drew out such a map, with coordinates, in a pixel art program: Now I would like to get all the coordinate points of the black squares. I ...
0
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1answer
234 views

What does “Poser-like” mean?

The Wavefront OBJ exporter of 3DSMax says it can flip YZ axis. Claiming this is "Poser-like". What does this mean? And what is the exact transformation if we decide to flip? Is it simply this? x ...
20
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3answers
986 views

What's so different/complicated/useful about vectors?

Forgive me if this isn't considered a real question, but it is something I am genuinely confused about. I constantly hear other game developers talk about how using vectors are very useful, but also ...
0
votes
1answer
457 views

Importing an object from Blender into a scene, rotation on X axis?

This is my situation: I save the scene with blender no export with any processing steps. Blender has x right y up -z into the scene for the view coordinates (OpenGL) I have x right y up -z into ...
1
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0answers
463 views

c++ opengl unproject not working [duplicate]

first of all, sorry for the bad english. I need to convert my mouse coordinates to world coordinates, I'm trying to use the glm unproject method. 1280x720 is the size of the window, It's hard coded ...
1
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0answers
143 views

How can I convert between float3 and float2 in HLSL?

I want to offload some 3D calculations to the GPU without raising my requirements to DX10. Specifically, I am generating densities in 64x64x64 3D blocks, which fit nicely into 512x512 2D textures. I ...
1
vote
1answer
216 views

Cartesian Coordinates & Layout [duplicate]

The way cartesian coordinations are presented and used is kinda confusing. When working with 2D the vertical axis is Y, though when working with 3D the vertical axis is Z and Y becomes the "depth" ...
4
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1answer
192 views

Can you help me solve the paradox that has confused me about the glViewport and glOrtho functions?

suppose that I have an image that I want to apply as a texture on a geometry (at time we don't consider texture mapping but this image has a certain width and height here it is a 512x512 image) I want ...
0
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0answers
231 views

How do I find the rotation point given a touch anchor, new position and new rotation?

I've got an Cocos2d layer which anchorPoint, position and rotation (according to http://www.qcmat.com/understanding-anchorpoint-in-cocos2d/) vary when the pinch zoom gestures. Everything works fine. ...
10
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2answers
464 views

World Bounds - (0, Size) or (-HalfSize, HalfSize)?

When creating a game space in which to move, draw and collide objects, is it better to have the (0,0) point, or the (0,0,0) point, be in the very center of your space, such that the bounds of the ...
0
votes
1answer
74 views

Get rotate angle using a formula

I am developing a game that is being played on a board with the top first tile having the coordinates [0,0], the next one has [0,1], second row has [1,0]... and so on (most likely this would be a ...
1
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2answers
402 views

What am I missing? (Converting 2D mouse coords to 3D space)

I'm making a networked game which has a birds-eye view and I'm trying to convert the 2D mouse coordinates into 3D space. Right now I have a perfectly flat grid and it intends to remain perfectly flat, ...
1
vote
0answers
120 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 ...
2
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2answers
173 views

Calculating specific coordinate along a path

Let's say I have a path comprised of a sequence of points that are connect by lines and arcs. The entire path has some specific length. Let's call that length 100. What would be the mechanism to ...
2
votes
1answer
189 views

Texturing spherical terrain, seemingly arbitrary distortion

I'm using this algorithm to find texture coordinates on a sphere: Wikipedia UV Coordinates I get the famous seam due to the wrong interpolation, but I also get odd distortions on certain points on ...
4
votes
1answer
604 views

2d coordinates vs x/y screen positioning

I have a 2d top-down view tile map game, that generates random color tiles (water colors) as you move the character. I've been positioning elements on screen using the x/y coords (finding a way to ...
0
votes
1answer
74 views

Getting correct direction of the Car [duplicate]

I am building a car racing game using the coordinate system in which I have enemies's cars and the player cars. I want to ask that what is the best way to find the the direction of enemies's cars so ...
1
vote
2answers
663 views

Converting hexagon grid coordinate system

As I have been building on a RTS game based on hexagon grid built in javascript. I stumbled across a problem regarding the coordinate system. Have been trying to implement a A-star system to find ...
1
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1answer
108 views

How to handle scaled aspect ratio multiplayer player coordinates

I'm building a cross platform multiplayer game. I'm using pixel graphics and starting at a small 256x144 16:9 aspect ratio That gets scaled up to larger 16:9 resolutions. The graphics look ok however ...
5
votes
1answer
243 views

How to flip coordinate system in Pyglet?

Is there any way I can flip the coordinate system in Pyglet vertically so that y = 0 is at the top of the screen and a higher y value is closer to the bottom? It is really confusing trying to use ...
1
vote
1answer
573 views

How can I convert screen coordinates to world coordinates on the floor (when the y component = 0)?

I am using the Irrlicht Engine and would like to convert the coordinates of the mouse on the screen to the floor of my world. I am currently trying to use getRayFromScreenCoordinates() which ...
-2
votes
3answers
113 views

Check for obstacle [closed]

Programming language: Pseudocode In my program there will be (among others) two variables, called varX and varY. They will have only positive values, but they may be of varying length. They will ...
3
votes
1answer
554 views

Choosing the correct isometric character facing direction

I am currently building a 3D game presented from a 2D isometric viewpoint. The 3D coordinates start at the top left corner of the screen with x and y increasing towards the right and bottom edges ...
1
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0answers
115 views

Rotate Points with Object in world space

I posted this in the original stack overflow then realized that a game-dev specific one exists. I am working on personal project that requires me to have 4 points surrounding an object (1 at each of ...
-2
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1answer
242 views

Game Editor - When screen is clicked, how do you identify what coordinate you clicked?

This is a follow-up to my earlier question: Game Editor - When screen is clicked, how do you identify which object that is clicked? Something I've noticed is that picking only calculates a ray and ...
2
votes
2answers
443 views

Why does handedness matter at all?

I'm really trying to understand this from a mathematical viewpoint. After all, numbers are numbers, the chirality or handedness depends on how one interprets it. Say I've three basis vectors x (1, 0, ...
0
votes
1answer
470 views

Ways to “invert Z-axis” in shader-based core-profile OpenGL?

In my hobbyist shader-based (non-FFP) GL (3.2+ core) "engine", everything in world-space and model-space is by design "left-handed" (and to stay that way), so X-axis goes from -1 ("left") to 1 ...
0
votes
2answers
1k views

How do I calculate the z-coordinate for a perspective-camera in 2D?

I'm new to LibGDX and trying to use DecalBatch with PerspectiveCamera, simply to have Z-coordinate for my sprites, as SpriteBatch does not offer that. However, I don't know how to calculate the ...
5
votes
3answers
3k views

Mapping 3D object coordinates to 2D screen coordinates with perspective projection

Sort of following on from where this person was in their topic: Matrix for 2D perspective What I have at the moment is a transformation matrix that's defined as follows: http://pastebin.com/GM6BhP0R ...
1
vote
3answers
3k views

What is the Box2D coordinates system?

I know that for Box2d I need to translate pixels to meters which is easy peasy. However my problem is what is the orientation of Box2D coordinates system? Is this the same as screen one (right += x, ...
1
vote
1answer
499 views

In 2d game logic, should I use pixels or world coordinates?

Currently in my game I handle the logic (collisions, movement) using pixels but I find it very limiting espiecially when thinking about variable speed. For example Box2D requires you to use ...
1
vote
0answers
432 views

Converting motionevent.getx and motionevent.gety to pixel or Object coordinates in the view

I am trying to draw buttons using OpenGL I have added a Gesture Listener for the GLSurface View now i have motionevent when ever the user touches. My question is how can i convert motionevent.getx and ...
3
votes
1answer
164 views

Calibration of a 6 DOF tracking device

Setting: In our facility we have a 3D laboratory with 3 large displays (two edge-to-edge on orthogonal walls, one on the ground, also edge-to-edge). Its primary use-case is exploring 3D virtual ...
1
vote
1answer
238 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 ...
1
vote
1answer
144 views

Blender 2.6: Move Mesh to X Coordinate of Another Mesh

An example: There are two planes A and B with the following median points: ( X | Y | Z ) M_A ( 3 | 2 | 2 ) M_B ( 6 | 1 | 1 ) Now I want to move the plane A on the X-axis to the X coordinate ...
13
votes
4answers
4k views

Why is Y up in many Games?

I learned at school that the z-axis is up. It is the same in modeling software like Blender. However in many games the y-axis is up. What is reason?
3
votes
1answer
354 views

Coordinates on the top left corner or center of the tile

I'm setting up a tile system where every tile has x and y coordinates. Right now I assume that the top left corner of the tile is positioned on it's coordinate on the screen, x = tileX * tileWidth and ...
9
votes
4answers
4k views

Staggered Isometric Map: Calculate map coordinates for point on screen

I know there are already a lot of resources about this, but I haven't found one that matches my coordinate system and I'm having massive trouble adjusting any of those solutions to my needs. What I ...
0
votes
1answer
295 views

Curiosity on any Smartphones that Run on Android 2.3.3 with Different Screen Reoslution

I have a question regarding about any smartphones that run only in Android 2.3.3. Is the size of screen or the screen resolution is always HVGA or does it have capable of running this OS (Android ...
2
votes
1answer
223 views

Coordinate spaces and transformation matrices

I'm trying to get an object from object space, into projected space using these intermediate matrices: The first matrix (I) is the one that transforms from object space into inertial space, but since ...
1
vote
1answer
92 views

XNA 3D coordinates seem off

I'm going through a book, and the example it gave me seems like is should work, but when I try and implement it, it falls short. My Camera class takes three vectors in to generate View and Projection ...
1
vote
1answer
352 views

Precise Touch Screen Dragging Issue: Trouble Aligning with the Finger due to Different Screen Resolution

Please, I need your help. I'm trying to make a game that will drag-n-drop a sprite/image while my finger follows precisely with the image without being offset. When I'm trying on a 900x1280 (in X ...