Computer geometry is a branch of computer science devoted to the study of algorithms which can be stated in terms of geometry.
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3answers
123 views
Check if 2 rectangles fit in another one, given their length and height
I was very intrigued with the manner to solve this problem. The program needs to know if 2 rectangles fit in another one, considering the lines of the 2 rectangles are always parallel to the other one'...
6
votes
2answers
94 views
Rectangle-segment collision detection
I am working with C++ and SDL, hoping to create a game later. I am implementing the collision detection between rectangles and segments.
I found this (NateS user's solution) about line-rectangle ...
5
votes
2answers
76 views
Grouping rectangles horizontally and vertically
As you can see the below code for each method is that same, except for the properties it uses. For example X vs Y and ...
5
votes
1answer
77 views
High performance triangle - axis aligned bounding box clipping
Implementation of a Robust (i.e. with a finite plane thickness) Sutherland–Hodgman algorithm for clipping polygons against an axis-aligned bounding box. I use the following code only for clipping ...
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0answers
31 views
Shortest bitonic tour
This a solution to the shortest bitonic tour using dynamic programming. Bitonic tour starts at the leftmost point then goes strictly rightward to the rightmost point and finally strictly leftward to ...
1
vote
0answers
39 views
Get vertical acceleration from rotation vector and accelerometer values
My goal here is to calculate the acceleration towards the ground, which I call "vertical acceleration". This seems to be working OK for the most part, except when there is a lot of rotation going on ...
2
votes
2answers
38 views
Find the best path amongst N random points
For an application with a graphical canvas, I want to generate N points. But then I want to link those points, and I want to find the best path through those points.
I wanted to use a dynamic ...
3
votes
0answers
61 views
Computing intersection of 2D infinite lines
I wrote a small program to compute intersection of 2D infinite lines using Boost Geometry
A line is defined by two points in Line class. The ...
1
vote
1answer
35 views
Find cells crossed by a line
This method find cells that are crossed by line A-B and adds them to one vector.
I have got some duplicates here and some lines of code are very similiar but they differ in one variable. Should this ...
4
votes
1answer
92 views
Perimeter of a polygon given its vertices
I recently completed this code challenge so just looking for some feedback on my code. The task is to read polygon coordinates from a file and calculate the perimeter, I was provided with a script ...
10
votes
1answer
112 views
Template class for Andrew's Monotone Chain Algorithm Convex Hull
This is my first attempt at writing a template class. I am implementing Andrew's Monotone Chain algorithm, as described here to calculate a 2D Convex Hull. Since this is my first try at templates, I ...
2
votes
1answer
55 views
Create a rotation matrix [closed]
I adapted this piece of code from a math book for game developers and the result is correct albeit with slight floating point errors.
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8
votes
2answers
829 views
Point inside Polygon check
I have written a method to determine whether a Vector2 lies inside a polygon or outside of it. The polygon is defined by an array of clockwise vertices, p[]. It returns true if the point is inside, ...
3
votes
2answers
85 views
Striped closed poly-line
I'm working on class Striped_polyline which represents a closed poly-line filled with equidistant horizontal lines1:
stripedpoly.cpp:
...
7
votes
3answers
306 views
Given a set of points and pairs of lines, count the number of points that are between the pairs of lines
This is a contest problem. The entire description is here.
In resume:
The question gives a point simulating a light explosion that always has a negative x coordinate, a set of pairs line segments on ...
8
votes
1answer
275 views
Count number of isosceles triangles in a set of points
Given a set of points, what is the number of isosceles triangles that can be formed with the combinations of all points in the set?
It is certain that 3 collinear points never exists in the set.
<...
4
votes
1answer
158 views
Project Euler 91 (via HackerRank): Right triangles with integer coordinates
This is my code to solve HackerRank's version of Project Euler Problem 91: on an N × N grid, find the number of possible right triangles where one vertex is (0, 0) and the other two vertices are ...
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3answers
843 views
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0answers
38 views
Scale geometry based on distance between 2 vertices - follow-up
Edit: Changes I made from previous script:
Reformatted lines of code to be more readable and correct for Python
Created individual functions for items that were previously crammed into singe ...
7
votes
2answers
186 views
Finding the maximum pairwise difference in a collection of colors
Note that this problem is equivalent to finding the longest line segment defined by any two points in a collection of 3D coordinates, which may be an easier way to visualize the problem, and is almost ...
6
votes
0answers
148 views
Graham scan implementation in Haskell
It looks like this is a really classical question, but I'd like to ask it one more time as all those solutions look quite long and complicated for me (maybe because I am dumb :) )
So this is a Graham ...
8
votes
1answer
466 views
Drawing circles with triangles
As pyglet has no in-built method to return a vertex list of circle, I had to build one myself. This is a critical piece of code that I will use very frequently. I need it to be of very fine ...
3
votes
1answer
72 views
Remove “lines” from a 2D vec
I have some code here that I am very unhappy with. The task I am trying to accomplish is this.
Given a 2d vec like this:
[[0 2 0] [1 3 5] [3 3 0]]
which can ...
6
votes
2answers
683 views
Python Trig Calculator
It's big, it's ugly, but it should work. My question is: how could I have implemented the "typeselection" function so it is less repetitive? Any tips on other improvements in coding style are welcomed ...
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votes
2answers
378 views
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5answers
291 views
Segment Intersection — Failing on Unknown Edge Cases
I was recently at a programming competition. One of the problems was to determine whether two line segments are parallel, intersect, or do not intersect.
For all of the test cases I ran, my solution ...
4
votes
1answer
225 views
Implementing Mitchell's best candidate algorithm
I have written an implementation of Mitchell's best candidate algorithm. Mitchell’s best-candidate algorithm generates a new random sample by creating k candidate samples and picking the best of k. ...
7
votes
1answer
1k views
Line segment to circle collision algorithm
I've written a function (in Python 3) which computes if a line segment (constraint) and a circle (body) collide, and returns the point of intersection (closest point to the centre of the circle):
<...
2
votes
2answers
154 views
Find non duplicate Triangle Triplets from a list of given numbers- version 3
It is a continuation of my previous question:
Find non duplicateTriangle Triplets from a list of given numbers
After I realized triplet structure using less space than ...
4
votes
1answer
80 views
Distance between angles as points
This code calculates the distance between angles, particularly for n-tuples of angles. One example where this situation occurs is as follows:
I'm using a 2 arms, one 6 degree of freedom and the other ...
2
votes
1answer
108 views
Find non duplicateTriangle Triplets from a list of given numbers
I implemented an O(N^2) algorithmic solution but not sure it is better than my previous implementation Find Triangle Triplets from a list of given numbers
in case of performance. I adapted almost ...
4
votes
1answer
206 views
Find Triangle Triplets from a list of given numbers
If a triplet of segments A, B and C are triangle triplets if and only
if
A + B > C
A + C > B
B + C > A
Is there a better implementation for this problem?
...
2
votes
0answers
591 views
fftshift implementation for OpenCV
I'm trying to implement fftshift from matlab for OpenCV. Can you please review the correctness of my algorithm? Have I missed something? Also, is there a better and faster way to do it?
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vote
2answers
67 views
Lazy properties for the angle and length of a line segment
The code below shows the pattern I use to manage properties in my classes when I have the following requirements:
Some properties are slow to calculate and are rarely used, so I want them to be lazy
...
3
votes
1answer
167 views
Scale object based on distance between 2 vertices
I made this script so that I can scale objects for 3D printing from Maya.
I had fun making it and I'm sure it could be cleaned up or improved. If it can be cleaned up please let me know.
...
2
votes
2answers
151 views
Comparing triangles using Java 8 streams
I'm trying to get more familiar with Java 8 streams as they seem to be very powerful (and shorter), so I rewrote a method to use streams. However I'm not very satisfied with it and would like some ...
6
votes
2answers
292 views
Speeding up 2D shadow algorithm
I wrote a class to represent a set of lights in a 2D game that raycast in order to find shadows. The draw method does a lot of calculations and takes a lot of time. Mainly, the adding of areas and ...
4
votes
2answers
128 views
Implementation of Graham Scan algorithm in Haskell
Here is an implementation of Graham Scan algorithm for computing the convex hull of a finite set of points:
...
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votes
3answers
208 views
Line passing the most number of points
Given points on a two dimensional graph, find a line that passes the most number of points.
Any comments please?
...
6
votes
1answer
116 views
Use of static factory methods for vectors and matrices library
I've been working on a Java-based mathematics library focusing on vectors and matrices. I plan to use it for an important upcoming project, so the classes are analogous to data types available in GLSL ...
4
votes
1answer
131 views
Tested cartesian plane utility
I am starting to explore automated testing of code, so I decided to write some trivial code about the cartesian plane and test it. I am particularly interested in automated testing conventions and ...
4
votes
2answers
401 views
Cubic “bezier” curve of grade n
This is code I wrote for calculating bezier curves as quickly and RAM efficiently as possible.
I would like to know if there are faster ways to optimize anything, because I am very new to C++ and ...
3
votes
0answers
136 views
Graphical editor with geometric intersection
If it is possible I would like some comments on the overall style of the program. It feels like I am writing the whole program as one big script and I'm not sure how to break it down into several ...
3
votes
1answer
192 views
Ray→plane and ray→quad intersection
This checks the intersection between a Ray and a Plane and between a Ray and a ...
2
votes
2answers
445 views
Haversine formula in SQL
This is an implementation of the Haversine formula in Microsoft Transact SQL.
How can I simplify the function?
...
6
votes
2answers
158 views
Quaternion rotations and preparing matrices for a shader
I am implementing an OpenGL ES 2.0 renderer in c. I want to use quaternions for rotations. Please take a look at the way I am implementing the rotation math. Everything looks as expected when the ...
6
votes
1answer
60 views
'Tis the season for gift-wrapping
When reviewing a Graham scan convex hull algorithm implementation, I wrote the following function in an answer:
...
7
votes
3answers
238 views
Checking for intersection points
The aim of the program is to find those points which comes under the intersection of at least 2 circles.(space is a 1000x1000 matrix)
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8
votes
1answer
2k views
Jarvis's March Convex Hull
I'm more concerned about the coding best practices and how it's written here than the actual algorithm and math. I'm concerned about stack constraints, passing arguments,..etc. If there is anything ...
4
votes
1answer
281 views
Generate sample coordinates inside a Polygon
I have a Polygon named as poly. I attempted to randomly select 5 coordinate points that lies inside the polygon.
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