A branch of mathematics concerned with questions of shape, size, relative position of figures, and the properties of space.

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-1
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2answers
68 views

Help with drawing a polygon with N sides [closed]

I am at university on my games development, and I have been given work to fill in an empty pixel plotter program using the methods they have supplied for it to teach us the algorithms used in 2 ...
0
votes
1answer
79 views

How could we use trigonometry for moving around a 3D World?

Well I have a question about geometry and 3-Dimensional player movement in general. I'm using Java, OpenGL and LWJGL. This is basically what I got: currentFrontSpeed: Is a float that contains the ...
1
vote
1answer
43 views

What is the best way to check for intersection of two bounding boxes, given a minimum and maximum Vector3 for each one

I have a BoundingBox object which holds two Vector3's (x, y, z), one for the minimum point and one for the maximum point. (-1.5 0 9 | 1.5 3 10) What is the best way to check for any intersection or ...
1
vote
1answer
48 views

How can I fade in 3D foliage smoothly?

Take a look at this picture: This is a picture of me diving down from a high height. As you can see, the world is a simple world with grass, snow, trees, etc. The problem here is the 3D foliage. If ...
0
votes
1answer
28 views

How to enforce touching within a ring shape?

I'd like to have the player moving the finger within the shaded ring: The game should be able to detect "out-of-boundary" events once the finger moves outside the ring. How can I accomplish this?
0
votes
1answer
60 views

What is the Z plane?

I am learning the basics of geometry shaders and I came across references to the "Z plane." It's pretty easy to visualize the X and Y planes, but where does the Z plane reside in Cartesian space? ...
3
votes
1answer
37 views

Vertex normals in the geometry shader using directx

I'm in directx 11 with the geometry shader. Is is possible to calculate vertex normals? Just one like segment per vertex? In the geometry shader? I did vertex normals per face, this is what I got, ...
1
vote
0answers
43 views

2d grid vision(eye sensor) for a neural network bot?

I have a 2d grid and neural network bots living above it. What is a good way to give them vision of tiles in front of them? Below I describe my idea that I don't know how to efficiently(or ...
4
votes
1answer
59 views

What is the fastest way of drawing simple, textured geomtries and keeping the depth test?

I'm looking for a fast way to draw simple 3D geometries - that will consist of up to 10 vertices. Each of them will have a texture (though varying between geometries). I also want to store the ...
4
votes
2answers
83 views

Generate Geodesic Sphere from Hex and Pentagons

I have two polygonal meshes, a hexagon and a pentagon (They are tiles in a strategy game). I want to use them to construct a geodesic sphere ...
5
votes
2answers
67 views

List cells in a 2D grid that belong in a sector / portion of a circle

Are there any algorithms to find out which cells in a 2D grid lie inside/is part of a slice of a circle - a pie slice shaped region? Essentially, as per image below, I need to list out all the green ...
0
votes
0answers
23 views

How to generate tangent and binormal(bitangent) of a triangle polygon mesh

I am currently using FBX sdk to acquire mesh information from obj and fbx files. However, not all meshes contain tangent and binormal(bitangent) information so I have to use the method ...
5
votes
0answers
66 views

Dual Contouring - Finding the feature point, normals off

I am following this tutorial to implement Dual Contouring http://www.sandboxie.com/misc/isosurf/isosurfaces.html My data source is a grid 16x16x16; I traverse this grid bottom to top, left to right, ...
2
votes
1answer
40 views

Finding vector from a vertex to a plane

I am trying to implement Dual Contouring, following serveral sources, mainly http://www.sandboxie.com/misc/isosurf/isosurfaces.html but now I want to implement finding the feature point as explained ...
5
votes
4answers
216 views

Creating force shields: the most efficient way of deforming/reshaping a simpler convex mesh so it envelopes a complex mesh?

So, the best way I can think of how to explain what I need is the following (images used here are just random images found trough google image search). What I am trying to create during run-time is ...
5
votes
1answer
124 views

Finding new position after collision with multiple colliders

What is the most accurate way to find the correct position to where a moving character should be re-positioned as a collision-resolution, after it has collided with multiple colliders? The figure ...
5
votes
2answers
88 views

How to find out the vertices of the polyhedron formed by the overlapping area of two rotated boxes?

What is the most efficient way for finding out the vertices of the polyhedron formed by the overlapping area of two rotated 3D boxes? If it is still confusing what I mean by "polyhedron formed ...
8
votes
4answers
542 views

How do I efficiently check if a point is inside a rotated rectangle?

Part for the sake of optimization, part for learning purposes, I will dare to ask: How can I most efficiently check whether a 2D point P is inside a 2D rotated rectangle XYZW, using C# or C++? ...
5
votes
2answers
740 views

Is there an efficient way to identify in which run-time generated room a character is, in a non-grid 3D environment? How?

Here is what I am trying to implement. I wrote a script that allows the player to place walls during run-time, in non grid-based 3D environment (walls can be diagonal with rotation ...
1
vote
0answers
93 views

Most efficient way to calculate angle between two line-segments that do not necessarily touch each other

Although I found answers on calculating angles from vectors, I didn't find a specific way to calculate angles between line-segments that do not necessarily touch each other (I say "not necessarily ...
2
votes
1answer
61 views

Realistic angular velocity for rolling sphere in Unity 5.1

I'm trying to make a small 2D game with a rolling ball/sphere using Unity 5.1, but if find the angular velocity of the ball weird. On this first image (http://imgur.com/8wBoGms), you can see the ...
2
votes
2answers
107 views

Most efficient way to get the world position of the 8 vertexes of a Box Collider (C#)

What I am looking for is the most efficient way to get the world position of the 8 vertexes of the Box Collider of a freely rotated Gameobject. I cannot use collider.bounds since object is rotated, ...
1
vote
0answers
40 views

Detecting the two Vector3 that determine the bottom-edge of the side of a box-collider that had collision (with C#)

So, I understand that plenty of questions have been posted on how to detect which side of a Box Collider had collision. However, what I am trying to achieve is a little different. I want to find out, ...
1
vote
0answers
59 views

Calculating Minimum Translation Vector in Separating Axis Theorem based algorithm

In the 2D SAT collision determination algorithm, you project the convex polygons onto each potential separating axis. Supposing the polygons intersect, from what I understand, the axis for which the ...
0
votes
2answers
73 views

Optimal way to find point D that lays at the perpendicular line between point A and line BC

I am trying to write a script in C# to find the position of point D in 2D space in a specific scenario. I know the (X,Y) position of point A, which never happens to be on the line that contains the ...
1
vote
3answers
120 views

What's the most efficient way to find the position of a point in relation to corners of a rectangle despite rectangle's scale

I am struggling to achieve the following with C# (in Unity). I need to find the position of the points that lay at a given distance (let's say 1m) from the corners of a rectangle, in a way that the ...
4
votes
2answers
113 views

How to properly rotate towards a local point in Unity C#? (a local LookAt)

I am having a nightmare trying to make a child object rotate towards a given point of its parent object, similar to what is possible at the world level when using LookAt. The problem is that most ...
2
votes
0answers
69 views

Rotate perspective camera to align screen width to procedural object's width (Unity, C#)

I give up. After much trying and searching, I have to say I was unable to achieve the following task, for which I must call for your wise advice. In my current Unity 5 application (using C#), there ...
0
votes
0answers
23 views

Drawing shapes within a rectangle area

I am working on a Objective-c project where I need to draw multiple rectangle shapes inside a rectangle area like the attached image. Basically calculating CGPoints inside the CGRect. Thanks in ...
0
votes
0answers
54 views

Project 2d click/touch onto 3d plane

I have a 3d scene that contains an infinite plane that is NOT parallel to the camera (so every screen coordinate corresponds to a point on this plane- in other words, there are no possible invalid ...
9
votes
4answers
216 views

How do I interpolate around a rectangle?

I want to make a fancy animation where a point travels around a rectangle. I want to find the point's position at a time t. The rectangle is given by X, Y, Width and Height. Is there an algorithm ...
1
vote
1answer
100 views

Sliding DOOM style collision resolution against arbitrary 2D geometry

I've been working on a HTML5 canvas raycasting engine for the web browser, with the end goal of making a simple FPS game in the style of the early 90s. The engine sits somewhere between Wolfenstein 3D ...
0
votes
0answers
33 views

boost/geometry replacement in Java/for the JVM (Destructable Box2D terrain)

I'd like to reimplement https://github.com/seemk/DestructibleBox2D in Java. The main problem is finding an adequate replacement for the boost/geometry library. Any ideas?
0
votes
0answers
38 views

3D Picking: Doesn't Work Consistently

I'm trying to implement a 3D picking function that at the moment simply calculates the ray being sent from the camera after the user clicks the mouse on the window. It kind of works well when the ...
0
votes
2answers
115 views

Rotate coordinates back after rotating game context (geometry)

To achieve something similar to the image below using HTML5 canvas one can simply write the following: var TO_RADIANS = 0.0174532925; context.translate(30, 20); context.rotate(30 * TO_RADIANS); ...
0
votes
0answers
27 views

Making a node map with PNG alpha channels

I currently creating a 2d game that requires the usage of boats that travel from one country to another. The countries are individual objects with there own png. Nehow I've got the original map of the ...
2
votes
2answers
71 views

Detect collision that happen between frames, between slices of moving, rotating circles?

To detect a collision between two circles, we check if the distance between their centers is smaller than the sum of their radii. To detect a collision between a slice (in this case half) of a circle ...
-1
votes
1answer
81 views

Why is this unity camera moving in weird directions?

I have the following script public class CameraScript : MonoBehaviour { public bool AllowZoom; public float zoom; public float Speed; Transform board; void Start(){ ...
3
votes
1answer
325 views

How can I mask this CanvasRenderer?

I'm creating a text box that allows for selectable text, based off of Unity's InputField. An issue I am now facing is that the selection highlight does not respond to masks (The parent has a mask, but ...
0
votes
2answers
61 views

Calculate land center on grid

I have a grid based game. The main map is 2d array with land ids, something like this (here are 2 lands on the map, one formed where the 1's are and one formed by where the 2's are): [ 1 , 2 , 2 ] [ ...
0
votes
0answers
180 views

Taking a 2D slice of a 3D volume

I have a regular 3D polygon and I'd like to display 2D slices of it. What is the best way to achieve this? (Preferrably in OpenGL, but a general algorithm/tecnique would be good as well). I've ...
0
votes
1answer
84 views

Is there a way of moving the transform of an object relative to it's geometry

I have a number of objects (mostly prefabs) that have their transform origin in inconvienient places such as about 1 unit to the left of the actual geometry or somewhere inside an object where it's ...
1
vote
1answer
72 views

Ortho projection of 3D points with a vector

I have 3D points and I need to make an 2D orthographic projection of them onto a plane that is defined by the origin and a normal n. The meaning of this is basically looking at the points from the top ...
4
votes
1answer
118 views

Suboptimal A* Pathfinding Solution Example using Manhattan Distance Heuristic

I believe using an overestimating heuristic with A* is not guaranteed to find the shortest path. Assuming an agent can travel as a bird using euclidean distances, the manhattan distance provides just ...
36
votes
9answers
6k views

How can I quantify a drawn line's straightness?

I'm working on a game which requires players to draw a line from a point A(x1,y1) to the other point B(x2,y2) on the screen of an Android device. I want to find how well that drawing fits to a ...
0
votes
2answers
153 views

Outline of plane slice of arbitrary object

How would you extract the outline of a shape from slicing a plane through an arbitrary object? Note: This is related to my Unity Answers question, but not exactly the same.
0
votes
1answer
282 views

Rotate Object Towards Direction in 2D

For my RTS game's physics engine, I'm trying to find out a clever way to make a unit face the direction it's moving in. Given a Vector2d direction of movement (its normalized velocity), how can I ...
1
vote
1answer
41 views

Maya 2015 Collada mesh transforms not applied

I am trying to load a dae (Collada) model into my 3d engine. The problem is they export the vertices and transforms seperately. So in Maya 2015 it looks like this In the game engine I have it simply ...
2
votes
1answer
105 views

Mapping Coplanar Vertices in 3D space on to a 2D Plane

Say I have a plane specified by a normal vector and point on the plane. I want to specify a 2-D co-ordinate system that lies 'across' the plane, and then use that to find the 2-dimensional distance ...
0
votes
2answers
209 views

Moving OBB vs. triangle intersection test

Requirements: to write a test function that, given a moving OBB (oriented bounding box) and a triangle, returns true whenever the OBB hits the triangle. The OBB is described by its half extents (h1, ...