5
votes
4answers
464 views

How do I convert from the global coordinate space to a local space?

Given an entity named EntityA, I want to define a local coordinate space, where the position of EntityA is the origin, its heading vector is the X axis, and the normal of the heading vector is the Y ...
2
votes
2answers
143 views

How do I convert screen coordinates to between -1 and 1?

I'm writing a function that allows me to click on my tiles. The origin for my tiles is the center, however, the mouse's origin is the top left. I need a way to transform my mouse coordinates into my ...
19
votes
3answers
915 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
68 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 ...
8
votes
4answers
3k 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 ...
3
votes
1answer
710 views

Spherical to Cartesian Coordinates

Well I'm reading the Frank's Luna DirectX10 book and, while I'm trying to understand the first demo, I found something that's not very clear at least for me. In the updateScene method, when I press A, ...
13
votes
1answer
405 views

Orthographic unit translation mismatch on grid (e.g. 64 pixels translates incorrectly)

I am looking for some insight into a small problem with unit translations on a grid. Update and Solved I solved my own issue. See below for details. Everything in this part of the post turned out to ...
4
votes
3answers
482 views

Convert point to its barymetric coordinates

I'm making a 2.5D game engine (in JavaScript) and I'm trying to get it to detect whether a block is under the cursor. This would be a simple task were it restricted to single-level isometric ...
2
votes
2answers
266 views

how to transform child elements position into a world position

I'm making a 2d space game in Javascript with canvas. In this game there's a bunch of spaceships, positioned in world space, with turrets, positioned relative to their parent ships. These objects also ...
1
vote
1answer
139 views

Map displacement transformation to texture space?

I am trying to displace geometry in object space without giving the appearance of texture warping. My idea is to displace the UV lookup by a relative amount to the geometry displacement. Any ...
2
votes
1answer
414 views

How to linearly transform vertices for large coordinate systems

Alright, so I'm working on a space game and well, I want it to have a lot of space! So I need a large coordinate system and for my rendering pipeline to not suffer from "vertex jittering" due to ...
2
votes
2answers
895 views

Converting from different handedness coordinate systems

I am currently porting a demo from XNA to DirectX which, as I understand it, both have coordinate systems with different handednesses. What are the things I need to bare in mind when converting ...
1
vote
3answers
126 views

Finding which side one point is from another point

I have a simple question I think, if point a is to the right of another point I a dirx to be 1, otherwise -1. Likewise for a diry var, if it's above the other point I want it to be -1 otherwise 1. ...
3
votes
3answers
716 views

Spot the difference game design help

I'm thinking of making a spot the difference game. But immediately I stumbled over a problem. I'm thinking of storing a "difference area" in the form of a x,y coordinate. However, because on a ...
3
votes
1answer
536 views

How do you get an object to orbit around a certain point on a 2d plane?

I had a concept for a game come to me this morning but I can't figure out how I'd go about implementing the movement. The general idea involves the left and right controls causing a sprite to go ...
2
votes
1answer
169 views

Integration of homogenous wave

I have a 2D matrix; each of its elements describes a homogenous coordinate in 3D wave (the values of wave coordinates are changed in time). The wave rendering is done with texture. I need to make an ...
3
votes
1answer
152 views

Coordinate based travel through multi-line path over elapsed time

I have implemented A* Path finding to decide the course of a sprite through multiple waypoints. I have done this for point A to point B locations but am having trouble with multiple waypoints, because ...
1
vote
1answer
166 views

Is there a memory read/write or performance difference when applying affine transformations on a movieclip rather basic elementary math

I am using Actionscript 3.0 to make games and I fall into the category of programmers who use ball.x+=5; ball.y+=5; in order to move a ball by 5 pixels horizontally and vertically. Well, now i seem ...
6
votes
5answers
4k views

Changing coordinate system from Z-up to Y-up

Blender's coordinate system is different from what I'm used to, in that Z points upwards instead of Y. What would be the simplest way of converting all the world data (so that all animations, texture ...
2
votes
1answer
349 views

Why isn't my world coordinate mapping back to the proper local coordinate?

I'm using XNA and am having a simple issue which I can't figure out. I'm just messing around and want to get a firm grasp of local/world space coordinates. Matrix rotateCharacter= ...