diff --git a/LICENCE.md b/LICENCE.md new file mode 100644 index 0000000..e72bfdd --- /dev/null +++ b/LICENCE.md @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. We, the Free Software Foundation, use the +GNU General Public License for most of our software; it applies also to +any other work released this way by its authors. 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Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +state the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. \ No newline at end of file diff --git a/README.md b/README.md index 29bf3db..3a25086 100644 --- a/README.md +++ b/README.md @@ -91,8 +91,7 @@ https://github.com/user-attachments/assets/cd1cf6c3-3550-4b40-a5ad-6ffeced9316c ### Gnomonic projection -To run the 2D ./gradlew run2D --args='gnomonic' -model, run the command +To run the 2D Gnomonic projection model, run the command ```bash ./gradlew run2D --args='gnomonic' @@ -104,34 +103,34 @@ https://github.com/user-attachments/assets/23b0f337-2429-4373-aad7-e0cc986aa4b7 ### 0. Project Setup -- A . [How to Run the Project](docs/running-the-project.md) -- B . [How to contribute](.github/CONTRIBUTING.md) -- C . [What for?](docs/what_for.md) +- A. [How to Run the Project](docs/running-the-project.md) +- B. [How to contribute](.github/CONTRIBUTING.md) +- C. [What for?](docs/what_for.md) ### I. Foundations in Hyperbolic Geometry -- A . [Introduction](docs/I/introduction.md) -- B . [Poincaré Disk Model](docs/I/basic-mathematics-in-the-poincare-disk-model.md) -- C . [Isometries](docs/I/isometries.md) +- A. [Introduction](docs/I/introduction.md) +- B. [Poincaré Disk Model](docs/I/basic-mathematics-in-the-poincare-disk-model.md) +- C. [Isometries](docs/I/isometries.md) ### II. Tessellations -- A . [Introduction to Tessellation](docs/II/introduction_to_tesslation.md) -- B . [Coordinate System](docs/II/coordinates_system.md) -- C . [Implementation](docs/II/implementation.md) +- A. [Introduction to Tessellation](docs/II/introduction_to_tesslation.md) +- B. [Coordinate System](docs/II/coordinates_system.md) +- C. [Implementation](docs/II/implementation.md) ### III. 3D Rendering -- A . Ray-Caster Maze (WIP) -- B . [Visual effects](docs/III/3d-effects.md) +- A. Ray-Caster Maze (WIP) +- B. [Visual effects](docs/III/3d-effects.md) ### IV. In-Depth Explorations -- A . [Other Models](docs/IV/other_models.md) +- A. [Other Models](docs/IV/other_models.md) ## Licence -See all about our license [here](/LICENCE) +See all about our license [here](LICENCE.md) ![GPL3](https://upload.wikimedia.org/wikipedia/commons/c/cb/GPLv3_Logo_filled.png) diff --git a/docs/.nojekyll b/docs/.nojekyll new file mode 100644 index 0000000..8d1c8b6 --- /dev/null +++ b/docs/.nojekyll @@ -0,0 +1 @@ + diff --git a/docs/435248313-cd564d2c-b59d-4107-a9d4-a5095251b5a3.mp4 b/docs/435248313-cd564d2c-b59d-4107-a9d4-a5095251b5a3.mp4 new file mode 100644 index 0000000..18031b3 Binary files /dev/null and b/docs/435248313-cd564d2c-b59d-4107-a9d4-a5095251b5a3.mp4 differ diff --git a/docs/435471805-cd1cf6c3-3550-4b40-a5ad-6ffeced9316c.mp4 b/docs/435471805-cd1cf6c3-3550-4b40-a5ad-6ffeced9316c.mp4 new file mode 100644 index 0000000..dcd55da Binary files /dev/null and b/docs/435471805-cd1cf6c3-3550-4b40-a5ad-6ffeced9316c.mp4 differ diff --git a/docs/439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 b/docs/439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 new file mode 100644 index 0000000..33cd799 Binary files /dev/null and b/docs/439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 differ diff --git a/docs/441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 b/docs/441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 new file mode 100644 index 0000000..95ac2d2 Binary files /dev/null and b/docs/441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 differ diff --git a/docs/441708869-b18b1862-54cd-4e70-bc3e-eb668aba2c67.mp4 b/docs/441708869-b18b1862-54cd-4e70-bc3e-eb668aba2c67.mp4 new file mode 100644 index 0000000..be094ac Binary files /dev/null and b/docs/441708869-b18b1862-54cd-4e70-bc3e-eb668aba2c67.mp4 differ diff --git a/docs/441708927-bc754d07-b1c2-435d-b459-7e679d5f27de.mp4 b/docs/441708927-bc754d07-b1c2-435d-b459-7e679d5f27de.mp4 new file mode 100644 index 0000000..3fe8d4d Binary files /dev/null and b/docs/441708927-bc754d07-b1c2-435d-b459-7e679d5f27de.mp4 differ diff --git a/docs/I/429670801-fc13c232-8755-4ced-a09e-4cbd4d35e02d.mp4 b/docs/I/429670801-fc13c232-8755-4ced-a09e-4cbd4d35e02d.mp4 new file mode 100644 index 0000000..a4db247 Binary files /dev/null and b/docs/I/429670801-fc13c232-8755-4ced-a09e-4cbd4d35e02d.mp4 differ diff --git a/docs/I/430622602-9a24ac4c-7504-471e-b9ec-f49a3f9c79f5.mp4 b/docs/I/430622602-9a24ac4c-7504-471e-b9ec-f49a3f9c79f5.mp4 new file mode 100644 index 0000000..82aabd2 Binary files /dev/null and b/docs/I/430622602-9a24ac4c-7504-471e-b9ec-f49a3f9c79f5.mp4 differ diff --git a/docs/I/430623630-7b52a693-1928-4205-96b5-63fa361ec08e.mp4 b/docs/I/430623630-7b52a693-1928-4205-96b5-63fa361ec08e.mp4 new file mode 100644 index 0000000..8d0887b Binary files /dev/null and b/docs/I/430623630-7b52a693-1928-4205-96b5-63fa361ec08e.mp4 differ diff --git a/docs/I/430654353-43b8c25a-ea0f-447e-a6e8-42bb7ddf9f10.mp4 b/docs/I/430654353-43b8c25a-ea0f-447e-a6e8-42bb7ddf9f10.mp4 new file mode 100644 index 0000000..d332b12 Binary files /dev/null and b/docs/I/430654353-43b8c25a-ea0f-447e-a6e8-42bb7ddf9f10.mp4 differ diff --git a/docs/I/431992681-f39a0f90-59ad-4b11-a409-f35d7ea86962.mp4 b/docs/I/431992681-f39a0f90-59ad-4b11-a409-f35d7ea86962.mp4 new file mode 100644 index 0000000..37e88ca Binary files /dev/null and b/docs/I/431992681-f39a0f90-59ad-4b11-a409-f35d7ea86962.mp4 differ diff --git a/docs/I/433169788-c9113e5d-2f8a-4996-af72-3f9cad6f2782.mp4 b/docs/I/433169788-c9113e5d-2f8a-4996-af72-3f9cad6f2782.mp4 new file mode 100644 index 0000000..320698c Binary files /dev/null and b/docs/I/433169788-c9113e5d-2f8a-4996-af72-3f9cad6f2782.mp4 differ diff --git a/docs/I/433169799-b7bea3fe-10f0-4d41-838d-b4e75249307a.mp4 b/docs/I/433169799-b7bea3fe-10f0-4d41-838d-b4e75249307a.mp4 new file mode 100644 index 0000000..bddbcd3 Binary files /dev/null and b/docs/I/433169799-b7bea3fe-10f0-4d41-838d-b4e75249307a.mp4 differ diff --git a/docs/I/433169809-e2048917-90da-4aa3-92c3-97be560b9f47.mp4 b/docs/I/433169809-e2048917-90da-4aa3-92c3-97be560b9f47.mp4 new file mode 100644 index 0000000..843e210 Binary files /dev/null and b/docs/I/433169809-e2048917-90da-4aa3-92c3-97be560b9f47.mp4 differ diff --git a/docs/I/433268541-f230a181-cefe-4da6-aec3-966e8b1aa580.mp4 b/docs/I/433268541-f230a181-cefe-4da6-aec3-966e8b1aa580.mp4 new file mode 100644 index 0000000..93f70a6 Binary files /dev/null and b/docs/I/433268541-f230a181-cefe-4da6-aec3-966e8b1aa580.mp4 differ diff --git a/docs/I/basic-mathematics-in-the-poincare-disk-model.md b/docs/I/basic-mathematics-in-the-poincare-disk-model.md index 28a174d..7ced0d2 100644 --- a/docs/I/basic-mathematics-in-the-poincare-disk-model.md +++ b/docs/I/basic-mathematics-in-the-poincare-disk-model.md @@ -4,9 +4,11 @@ ### hyperboloid -In hyperbolic geometry, one elegant way to visualize non-Euclidean space is through the Poincaré disk model. This model can be derived from a higher-dimensional perspective by considering a [two-sheeted hyperboloid](https://en.wikipedia.org/wiki/Hyperboloid#Hyperboloid_of_two_sheets). By introducing an extra dimension, we can construct the [hyperboloid](https://en.wikipedia.org/wiki/Hyperboloid) where its equation typically takes the form : $$x^2 + y^2 - z^2 = -1$$ with one sheet (usually the upper one) representing the set of points with $z > 0$. +In hyperbolic geometry, one elegant way to visualize non-Euclidean space is through the Poincaré disk model. This model can be derived from a higher-dimensional perspective by considering a [two-sheeted hyperboloid](https://en.wikipedia.org/wiki/Hyperboloid#Hyperboloid_of_two_sheets). By introducing an extra dimension, we can construct the [hyperboloid](https://en.wikipedia.org/wiki/Hyperboloid) where its equation typically takes the form : %%x^2 + y^2 - z^2 = -1%% with one sheet (usually the upper one) representing the set of points with %%z > 0%%. -https://github.com/user-attachments/assets/fc13c232-8755-4ced-a09e-4cbd4d35e02d +![filename](429670801-fc13c232-8755-4ced-a09e-4cbd4d35e02d.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/fc13c232-8755-4ced-a09e-4cbd4d35e02d) ### Points @@ -20,14 +22,16 @@ $$H = \{ (a, b, c) \in \mathbb{R}^3 \mid a^2 + b^2 - c^2 = -1, \quad c > 0 \}.$$ The Poincaré disk model is given by the unit disk in the Euclidean plane: $$D = \{ (x, y) \in \mathbb{R}^2 \mid x^2 + y^2 < 1 \}$$ -The stereographic projection from the upper sheet of the hyperboloid model $H$ onto the Poincaré disk $D$ is defined as follows. Given a point $P(a, b, c) \in H $, the corresponding point $P'$ in the disk $D$ is: +The stereographic projection from the upper sheet of the hyperboloid model %%H%% onto the Poincaré disk %%D%% is defined as follows. Given a point %%P(a, b, c) \in H %%, the corresponding point %%P'%% in the disk %%D%% is: $$P' \left( x, y \right) = \left( \frac{a}{c+1}, \frac{b}{c+1} \right).$$ This establishes a map between the upper sheet of the hyperboloid and the unit disk. _A simple [Desmos](https://www.desmos.com/3d/nh9airbdob) example_ -https://github.com/user-attachments/assets/43b8c25a-ea0f-447e-a6e8-42bb7ddf9f10 +![filename2](430654353-43b8c25a-ea0f-447e-a6e8-42bb7ddf9f10.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/43b8c25a-ea0f-447e-a6e8-42bb7ddf9f10) ### Geodesies @@ -35,23 +39,27 @@ In general geometry, a [geodesic](https://en.wikipedia.org/wiki/Geodesic) is the The hyperbolic plane, because of this curvature, the shortest paths, or geodesics, are not straight lines in the usual sense but instead take specific forms depending on the model used to represent the hyperbolic plane. -https://github.com/user-attachments/assets/9a24ac4c-7504-471e-b9ec-f49a3f9c79f5 +![filename3](430622602-9a24ac4c-7504-471e-b9ec-f49a3f9c79f5.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/9a24ac4c-7504-471e-b9ec-f49a3f9c79f5) ### Circles Circles in the hyperbolic plane are also quite different from their Euclidean counterparts. A hyperbolic circle consists of all points at a fixed hyperbolic distance from a given center. However, due to the nature of hyperbolic distance, these circles often appear distorted in Euclidean representations of the hyperbolic plane. In the Poincaré disk model, hyperbolic circles resemble Euclidean circles but have different radii when measured with hyperbolic distance. The key difference is that the hyperbolic radius grows exponentially compared to the Euclidean radius. -https://github.com/user-attachments/assets/7b52a693-1928-4205-96b5-63fa361ec08e +![filename4](430623630-7b52a693-1928-4205-96b5-63fa361ec08e.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/7b52a693-1928-4205-96b5-63fa361ec08e) ## Geometry in the Poincaré disk model -The Poincaré disk model provides a conformal map of the hyperbolic plane onto the Euclidean unit disk $D={(x,y)∈R^2∣x^2+y^2<1}$. This means that while distances and straight lines (geodesics) are represented differently, angles between intersecting curves are preserved just as they are in the hyperbolic space itself. +The Poincaré disk model provides a conformal map of the hyperbolic plane onto the Euclidean unit disk %%D={(x,y)∈R^2∣x^2+y^2<1}%%. This means that while distances and straight lines (geodesics) are represented differently, angles between intersecting curves are preserved just as they are in the hyperbolic space itself. ### Hyperbolic Distance (Intuitive Notion) -One of the most striking features of the Poincaré disk is how it represents hyperbolic distance. Unlike the Euclidean plane where distance is uniform, in the Poincaré disk, distances become increasingly large as you approach the boundary circle ($x^2+y^2=1$). Imagine the disk as a map of an infinite world; the boundary circle represents "infinity." Moving from the center towards the edge requires exponentially more effort (or covers exponentially more hyperbolic distance) for the same Euclidean distance traveled on the map. +One of the most striking features of the Poincaré disk is how it represents hyperbolic distance. Unlike the Euclidean plane where distance is uniform, in the Poincaré disk, distances become increasingly large as you approach the boundary circle (%%x^2+y^2=1%%). Imagine the disk as a map of an infinite world; the boundary circle represents "infinity." Moving from the center towards the edge requires exponentially more effort (or covers exponentially more hyperbolic distance) for the same Euclidean distance traveled on the map. -For two points P1​ and P2​ inside the disk, the hyperbolic distance d(P1​,P2​) is not simply the Euclidean distance between them. The formula involves logarithms and depends on their positions relative to the center and the boundary. Intuitively, two points close to the boundary, even if they look close in the Euclidean sense within the disk, can be very far apart in terms of hyperbolic distance. +For two points %%P_1%%​ and %%P_2%%​ inside the disk, the hyperbolic distance %%d(P_1​,P_2​)%% is not simply the Euclidean distance between them. The formula involves logarithms and depends on their positions relative to the center and the boundary. Intuitively, two points close to the boundary, even if they look close in the Euclidean sense within the disk, can be very far apart in terms of hyperbolic distance. Understanding the reason for this formula is not necessary: @@ -66,11 +74,13 @@ $$ In hyperbolic geometry, geodesics are the paths of shortest distance between two points. In the Poincaré disk model, these paths are not Euclidean straight lines (unless they pass through the center of the disk). Instead, geodesics take two forms: - Diameters: Any straight line segment that passes through the center of the disk (i.e., a diameter) represents a hyperbolic geodesic. -- Circular Arcs Orthogonal to the Boundary: Any arc of a Euclidean circle that intersects the boundary circle ($x^2+y^2=1$) at a right angle (90 degrees) represents a hyperbolic geodesic. +- Circular Arcs Orthogonal to the Boundary: Any arc of a Euclidean circle that intersects the boundary circle (%%x^2+y^2=1%%) at a right angle (90 degrees) represents a hyperbolic geodesic. + +The circular arcs orthogonal to the boundary can be described by two reals a and b such that the circle is equal to %%x^2+y^2+a.x+b.y=0%% -The circular arcs orthogonal to the boundary can be described by two reals a and b such that the circle is equal to $x^2+y^2+a.x+b.y=0$ +![filename5](431992681-f39a0f90-59ad-4b11-a409-f35d7ea86962.mp4 ':include :type=iframe') -https://github.com/user-attachments/assets/f39a0f90-59ad-4b11-a409-f35d7ea86962 +[Source](https://github.com/user-attachments/assets/f39a0f90-59ad-4b11-a409-f35d7ea86962) ### Circles (Brief Mention) diff --git a/docs/disk.svg b/docs/I/disk.svg similarity index 100% rename from docs/disk.svg rename to docs/I/disk.svg diff --git a/docs/I/introduction.md b/docs/I/introduction.md index f5d425e..b08206d 100644 --- a/docs/I/introduction.md +++ b/docs/I/introduction.md @@ -1,4 +1,4 @@ -# introduction +# Introduction ## Introduction to Euclidean Geometry & Beyond @@ -28,7 +28,9 @@ tool: [the Poincaré disk model](https://en.wikipedia.org/wiki/Poincar%C3%A9_dis ## The Poincaré disk model -![poincaré disk model](/docs/disk.svg) +
+ +
In the [Poincaré disk](https://en.wikipedia.org/wiki/Poincar%C3%A9_disk_model), the entire infinite hyperbolic plane is compressed into the interior of a circle. But there’s a catch—the edge of the circle represents points at infinity. Just diff --git a/docs/I/isometries.md b/docs/I/isometries.md index 19b57a8..a170660 100644 --- a/docs/I/isometries.md +++ b/docs/I/isometries.md @@ -2,7 +2,7 @@ ## Euclidean Isometry -A **Euclidean [isometry](https://en.wikipedia.org/wiki/Isometry)** is a transformation of the Euclidean space that preserves distances between all points. In other words, if you have a map $f: \mathbb{R}^n \to \mathbb{R}^n$, it is an isometry if, for every pair of points $x$ and $y$ in the space, the distance between $x$ and $y$ is exactly the same as the distance between $f(x)$ and $f(y)$; mathematically, +A **Euclidean [isometry](https://en.wikipedia.org/wiki/Isometry)** is a transformation of the Euclidean space that preserves distances between all points. In other words, if you have a map %%f: \mathbb{R}^n \to \mathbb{R}^n%%, it is an isometry if, for every pair of points %%x%% and %%y%% in the space, the distance between %%x%% and %%y%% is exactly the same as the distance between %%f(x)%% and %%f(y)%%; mathematically, $$d(f(x), f(y)) = d(x, y).$$ @@ -12,31 +12,39 @@ The consequence of this property is that the overall shape, size, and angles of - **[Rotations]():** Turning the figure around a fixed center while keeping the distances from the center the same. - **[Reflections]():** Flipping the figure over a line (in the plane) or a plane (in space) such that the mirror image is congruent to the original. -https://github.com/user-attachments/assets/f230a181-cefe-4da6-aec3-966e8b1aa580 +![filename](433268541-f230a181-cefe-4da6-aec3-966e8b1aa580.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/f230a181-cefe-4da6-aec3-966e8b1aa580) Together, these transformations form the Euclidean group, which encompasses all the symmetries of Euclidean space. ## Non-Euclidean Isometries – An Intuitive Overview > [!IMPORTANT] -> It is useful to understand the key concepts of complex numbers and their geometric interpretation. For more information, see the [Complex Numbers](/docs/complex_numbers.md) page. +> It is useful to understand the key concepts of complex numbers and their geometric interpretation. For more information, see the [Complex Numbers](complex_numbers.md) page. In non-Euclidean geometries, the notion of an isometry retains the essential idea of distance preservation, but it adapts to the underlying curved space. In particular, the isometries of hyperbolic space differ from those of Euclidean and spherical space in the following ways: -- **Hyperbolic Translations:** In hyperbolic space, the concept of a translation differs from the Euclidean case. Instead of sliding along a straight line in flat space, hyperbolic translations move points along geodesics in a manner that preserves the hyperbolic distance. Mathematically, a hyperbolic translation function can be written as a [Mobius transformation](https://en.wikipedia.org/wiki/M%C3%B6bius_transformation) of the form $f(z) = \frac{z - a}{1 - \overline{a} z}$, where $a$ is a [complex number](https://en.wikipedia.org/wiki/Complex_number). +- **Hyperbolic Translations:** In hyperbolic space, the concept of a translation differs from the Euclidean case. Instead of sliding along a straight line in flat space, hyperbolic translations move points along geodesics in a manner that preserves the hyperbolic distance. Mathematically, a hyperbolic translation function can be written as a [Mobius transformation](https://en.wikipedia.org/wiki/M%C3%B6bius_transformation) of the form %%f(z) = \frac{z - a}{1 - \overline{a} z}%%, where %%a%% is a [complex number](https://en.wikipedia.org/wiki/Complex_number). + +![filename2](433169788-c9113e5d-2f8a-4996-af72-3f9cad6f2782.mp4 ':include :type=iframe') -https://github.com/user-attachments/assets/c9113e5d-2f8a-4996-af72-3f9cad6f2782 +[Source](https://github.com/user-attachments/assets/c9113e5d-2f8a-4996-af72-3f9cad6f2782) -- **Rotations:** Around a fixed point, you can rotate figures similarly to Euclidean rotations, but the way distances and angles behave is governed by the hyperbolic metric. These rotations preserve the structure and distance relationships as defined in the hyperbolic model. Mathematically, a hyperbolic rotation function can be written as a [Mobius transformation](https://en.wikipedia.org/wiki/M%C3%B6bius_transformation) of the form $f(z) = e^{i \theta} z$, where $\theta$ is the angle of rotation. +- **Rotations:** Around a fixed point, you can rotate figures similarly to Euclidean rotations, but the way distances and angles behave is governed by the hyperbolic metric. These rotations preserve the structure and distance relationships as defined in the hyperbolic model. Mathematically, a hyperbolic rotation function can be written as a [Mobius transformation](https://en.wikipedia.org/wiki/M%C3%B6bius_transformation) of the form %%f(z) = e^{i \theta} z%%, where %%\theta%% is the angle of rotation. -https://github.com/user-attachments/assets/b7bea3fe-10f0-4d41-838d-b4e75249307a +![filename3](433169799-b7bea3fe-10f0-4d41-838d-b4e75249307a.mp4 ':include :type=iframe') -- **Reflections and Glide Reflections:** Just like in Euclidean geometry, hyperbolic geometry allows for reflections across geodesic lines and combinations of reflections and translations (glide reflections), all while preserving the hyperbolic distances. Mathematically, a reflection function can be written as a [inverse function](https://en.wikipedia.org/wiki/Inversive_geometry) with respect to the euclidean circle that represents the geodesic line. We have, where $R$ is the radius of the circle and $(x_0, y_0)$ is the center of the circle, $(x, y)$ is the point of reflection and $(f(x), g(y))$ is the reflected point. +[Source](https://github.com/user-attachments/assets/b7bea3fe-10f0-4d41-838d-b4e75249307a) + +- **Reflections and Glide Reflections:** Just like in Euclidean geometry, hyperbolic geometry allows for reflections across geodesic lines and combinations of reflections and translations (glide reflections), all while preserving the hyperbolic distances. Mathematically, a reflection function can be written as a [inverse function](https://en.wikipedia.org/wiki/Inversive_geometry) with respect to the euclidean circle that represents the geodesic line. We have, where %%R%% is the radius of the circle and %%(x_0, y_0)%% is the center of the circle, %%(x, y)%% is the point of reflection and %%(f(x), g(y))%% is the reflected point. $$f(x) = x_0 + \frac{R^2 (x - x_0)}{(x - x_0)^2 + (y - y_0)^2}$$ $$g(y) = y_0 + \frac{R^2 (y - y_0)}{(x - x_0)^2 + (y - y_0)^2}$$ -https://github.com/user-attachments/assets/e2048917-90da-4aa3-92c3-97be560b9f47 +![filename4](433169809-e2048917-90da-4aa3-92c3-97be560b9f47.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/e2048917-90da-4aa3-92c3-97be560b9f47) Intuitively, hyperbolic isometries are all the “symmetry moves” that you can apply without altering the intrinsic geometry of a hyperbolic plane—no stretching or shrinking occurs, only repositioning within the framework of hyperbolic distance. 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In a Euclidean tiling, a discrete coordinate system is rather straightforward (see [discrete coordinate systems for plane tilings](https://duriansoftware.com/joe/discrete-coordinate-systems-for-plane-tilings)). However, for a hyperbolic tiling, the problem is more complex. Interestingly, I found no existing documentation online on this subject, so I developed my own system. @@ -12,7 +12,9 @@ In a Euclidean tiling, a discrete coordinate system is rather straightforward (s 2. **Determining Neighboring Tile Directions:** Once the initial orientation is set, we can, for instance, define the direction to reach the immediately adjacent left tile. The rule applied here is: the “upward” direction corresponds to the edge directly in front of the incoming edge. By repeatedly applying this rule, we can assign a direction to every neighboring tile in the tiling. -![coordinates](https://github.com/user-attachments/assets/747fc1ee-0ace-44b0-91a4-5bda74878908) +![coordinates](434903652-747fc1ee-0ace-44b0-91a4-5bda74878908.png) + +[Source](https://github.com/user-attachments/assets/747fc1ee-0ace-44b0-91a4-5bda74878908) Below is a brief example that demonstrates how to build a list of directions, and how the order of these directions is crucial. In this system, the sequence "Forward, Right" is not equivalent to "Right, Forward." @@ -61,7 +63,9 @@ The simplification rule for `Y'` is: This rule is applied recursively and removes unnecessary steps, helping reduce the sequence to a canonical form. -![backward_destruction](https://github.com/user-attachments/assets/0c6d03f6-2ab0-410f-8416-bdcc3971b1f9) +![backward_destruction](434905579-0c6d03f6-2ab0-410f-8416-bdcc3971b1f9.png) + +[Source](https://github.com/user-attachments/assets/0c6d03f6-2ab0-410f-8416-bdcc3971b1f9) ### Rule 2: Repeated Direction Merging @@ -80,7 +84,9 @@ Examples: These rewrites not only reduce the number of steps but also stabilize the orientation for further simplification. -![repeated_direction_merging](https://github.com/user-attachments/assets/dffaf00a-2c80-49a1-a035-26a4b012f2f2) +![repeated_direction_merging](434906904-dffaf00a-2c80-49a1-a035-26a4b012f2f2.png) + +[Source](https://github.com/user-attachments/assets/dffaf00a-2c80-49a1-a035-26a4b012f2f2) ### Rule 3: LF Pattern Transformation @@ -98,7 +104,9 @@ X.clockwise + (Left + Forward) * n + Left + Y.clockwise This transformation reorients the structure and reinterprets the motion path in a cleaner, mirrored format. -![lf_pattern_transformation](https://github.com/user-attachments/assets/02f86a1b-40c2-4969-b8f0-8ceca6b20691) +![lf_pattern_transformation](434907959-02f86a1b-40c2-4969-b8f0-8ceca6b20691.png) + +[Source](https://github.com/user-attachments/assets/02f86a1b-40c2-4969-b8f0-8ceca6b20691) ### Holonomy diff --git a/docs/II/implementation.md b/docs/II/implementation.md index 6ce2d6b..cb488dd 100644 --- a/docs/II/implementation.md +++ b/docs/II/implementation.md @@ -1,23 +1,23 @@ # Implementation -In this chapter, we describe the implementation of a hyperbolic tiling system in Java. We explore how to combine [isometries](../I/isometries.md), a [coordinate system](./coordinates_system.md), and some fundamental mathematical tools to construct a dynamic and interactive 2D representation of hyperbolic space. +In this chapter, we describe the implementation of a hyperbolic tiling system in Java. We explore how to combine [isometries](I/isometries.md), a [coordinate system](II/coordinates_system.md), and some fundamental mathematical tools to construct a dynamic and interactive 2D representation of hyperbolic space. ## Overview -Hyperbolic space allows infinitely many types of tessellations. However, for a given `{p,q}` tessellation — where `p` is the number of polygon sides and `q` is the number of polygons meeting at each vertex — all such tilings must be of consistent size and shape. +Hyperbolic space allows infinitely many types of tessellations. However, for a given %%\{p,q\}%% tessellation — where %%p%% is the number of polygon sides and %%q%% is the number of polygons meeting at each vertex — all such tilings must be of consistent size and shape. -We model the hyperbolic plane within a Euclidean coordinate system by embedding it in a unit disk. The center of this disk is denoted as $C_\infty$, and all transformations (rotations, translations) are applied relative to this center. +We model the hyperbolic plane within a Euclidean coordinate system by embedding it in a unit disk. The center of this disk is denoted as %%C_\infty%%, and all transformations (rotations, translations) are applied relative to this center. ## Tile Initialization -We begin by constructing the initial tile (a quadrilateral, for simplicity) centered at $C_\infty$. This tile is defined by: +We begin by constructing the initial tile (a quadrilateral, for simplicity) centered at %%C_\infty%%. This tile is defined by: - **4 vertices**: the corners of the polygon in Euclidean coordinates, - **a list of directions**: which define neighboring tiles. These two elements are stored in a structure we call a _chunk_. -To compute the distance from the center $C_\infty$ to a vertex of the central polygon, we use the following formula: +To compute the distance from the center %%C_\infty%% to a vertex of the central polygon, we use the following formula: $$ d = \sqrt{\frac{\tan\left(\frac{\pi}{2} - \frac{\pi}{q}\right) - \tan\left(\frac{\pi}{p}\right)}{\tan\left(\frac{\pi}{2} - \frac{\pi}{q}\right) + \tan\left(\frac{\pi}{p}\right)}} @@ -95,7 +95,7 @@ To render the hyperbolic tiling beyond the central tile, we need to generate all The generation of neighbors is done iteratively by expanding layers of adjacency around the center. Each chunk has a fixed number of sides (in our case, four), and each side corresponds to a possible direction toward a neighboring chunk. -To find a neighboring chunk in a given direction, we use **reflection**. This operation is covered in the [isometries](../I/isometries.md) chapter: each edge of a polygon defines a mirror line. Reflecting the tile across this line gives the adjacent tile in that direction. By repeating this process across different edges and tiles, we can navigate the infinite structure of hyperbolic space. +To find a neighboring chunk in a given direction, we use **reflection**. This operation is covered in the [isometries](I/isometries.md) chapter: each edge of a polygon defines a mirror line. Reflecting the tile across this line gives the adjacent tile in that direction. By repeating this process across different edges and tiles, we can navigate the infinite structure of hyperbolic space. ### Neighbor Expansion by Depth diff --git a/docs/II/introduction_to_tesslation.md b/docs/II/introduction_to_tesslation.md index 282bcb4..35aa888 100644 --- a/docs/II/introduction_to_tesslation.md +++ b/docs/II/introduction_to_tesslation.md @@ -8,28 +8,32 @@ A **Euclidean paving** is a way of subdividing a flat, two-dimensional Euclidean To describe a regular tiling, we use two parameters: -- $p$: the number of sides of each polygon, -- $q$: the number of polygons meeting at a vertex. +- %%p%%: the number of sides of each polygon, +- %%q%%: the number of polygons meeting at a vertex. -This gives us the notation **{p, q}**, commonly used to describe tilings. +This gives us the notation %%\{p, q\}%%, commonly used to describe tilings. ### Example: Hexagonal Tiling -In a **hexagonal tiling**, each tile is a regular hexagon ($p = 6$), and three hexagons meet at each vertex ($q = 3$). This gives us the notation **{6, 3}**. +In a **hexagonal tiling**, each tile is a regular hexagon (%%p = 6%%), and three hexagons meet at each vertex (%%q = 3%%). This gives us the notation %%\{6, 3\}%%. -![Hexagonal tiling](https://upload.wikimedia.org/wikipedia/commons/7/72/Hexagon_Tiling.svg) +![Hexagonal tiling](Hexagon_Tiling.svg) + +[Source](https://upload.wikimedia.org/wikipedia/commons/7/72/Hexagon_Tiling.svg) By the way, if you're working with hexagonal grids in programming, check out my Rust library called [**hexing**](https://github.com/cocosol007/hexing), which provides tools for manipulating hexagonal tilings efficiently. ### Example: Triangular Tiling -Here, the tiles are equilateral triangles ($p = 3$), and six triangles meet at each vertex ($q = 6$). This tiling is represented as **{3, 6}**. +Here, the tiles are equilateral triangles (%%p = 3%%), and six triangles meet at each vertex (%%q = 6%%). This tiling is represented as %%\{3, 6\}%%. + +![Triangle tiling](Triangle_Tiling.svg) -![Triangle tiling](https://upload.wikimedia.org/wikipedia/commons/2/23/Triangle_Tiling.svg) +[Source](https://upload.wikimedia.org/wikipedia/commons/2/23/Triangle_Tiling.svg) ### Example: Square Tiling -The most familiar one: squares with four meeting at each vertex, so $p = 4$, $q = 4$, written as **{4, 4}**. +The most familiar one: squares with four meeting at each vertex, so %%p = 4%%, %%q = 4%%, written as %%\{4, 4\}%%. --- @@ -37,13 +41,13 @@ The most familiar one: squares with four meeting at each vertex, so $p = 4$, $q For a tiling to work in the **Euclidean plane**, the internal angles around each vertex must add up to exactly 360°. This requirement leads to a simple formula: -$\frac{1}{p} + \frac{1}{q} = \frac{1}{2}$ +$$\frac{1}{p} + \frac{1}{q} = \frac{1}{2}$$ Solving this, we find that **only three regular tilings** are possible in the Euclidean plane: -- {3, 6} — triangle tiling -- {4, 4} — square tiling -- {6, 3} — hexagonal tiling +- %%\{3, 6\}%% — triangle tiling +- %%\{4, 4\}%% — square tiling +- %%\{6, 3\}%% — hexagonal tiling --- @@ -55,7 +59,7 @@ In **hyperbolic geometry**, the space is curved negatively—think of a saddle s In hyperbolic tilings, the angle sum around a point can be _less than_ 360°, which changes our condition to: -$\frac{1}{p} + \frac{1}{q} < \frac{1}{2}$ +$$\frac{1}{p} + \frac{1}{q} < \frac{1}{2}$$ This small difference opens up a vast new world: **infinitely many** regular tilings are possible in hyperbolic space! @@ -63,10 +67,16 @@ This small difference opens up a vast new world: **infinitely many** regular til Here are a few beautiful examples of hyperbolic tilings: -![37](https://github.com/user-attachments/assets/bccb3abc-a63c-4961-b86e-a9816b00ca78) +![pic1](434410550-bccb3abc-a63c-4961-b86e-a9816b00ca78.jpg) + +[Source](https://github.com/user-attachments/assets/bccb3abc-a63c-4961-b86e-a9816b00ca78) + +![pic2](434410575-10625ba6-19bf-43cd-b392-66276e57fa71.jpg) + +[Source](https://github.com/user-attachments/assets/10625ba6-19bf-43cd-b392-66276e57fa71) -![45](https://github.com/user-attachments/assets/10625ba6-19bf-43cd-b392-66276e57fa71) +![pic3](434410589-a48dc8f4-4bfb-434d-95e9-a9ad505794ee.jpg) -![73](https://github.com/user-attachments/assets/a48dc8f4-4bfb-434d-95e9-a9ad505794ee) +[Source](https://github.com/user-attachments/assets/a48dc8f4-4bfb-434d-95e9-a9ad505794ee) -You can play with these and generate your own using [this interactive site](https://www.malinc.se/noneuclidean/en/poincaretiling.php). Choose different values for $p$ and $q$ and explore how hyperbolic tilings behave! +You can play with these and generate your own using [this interactive site](https://www.malinc.se/noneuclidean/en/poincaretiling.php). Choose different values for %%p%% and %%q%% and explore how hyperbolic tilings behave! diff --git a/docs/III/3d-effects.md b/docs/III/3d-effects.md index 0a47922..667c993 100644 --- a/docs/III/3d-effects.md +++ b/docs/III/3d-effects.md @@ -1,6 +1,8 @@ # Understanding 3D Visual Effects in Hyperbolic Geometry -https://github.com/user-attachments/assets/5156987d-9099-42a6-9bd4-1a86abcd819e +![file](441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/5156987d-9099-42a6-9bd4-1a86abcd819e) In the 3D rendering engine, two striking visual effects consistently appear when the viewpoint moves: an apparent **rotation during lateral movement**, and a **zooming effect when moving forward**. While these phenomena may seem strange to an observer used to Euclidean geometry, they arise naturally from the fundamental properties of hyperbolic space. diff --git a/docs/III/441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 b/docs/III/441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 new file mode 100644 index 0000000..95ac2d2 Binary files /dev/null and b/docs/III/441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 differ diff --git a/docs/IV/439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 b/docs/IV/439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 new file mode 100644 index 0000000..33cd799 Binary files /dev/null and b/docs/IV/439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 differ diff --git a/docs/IV/Poincare_halfplane_heptagonal_hb.svg b/docs/IV/Poincare_halfplane_heptagonal_hb.svg new file mode 100644 index 0000000..48fa17c --- /dev/null +++ b/docs/IV/Poincare_halfplane_heptagonal_hb.svg @@ -0,0 +1,2820 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + 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+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/docs/IV/other_models.md b/docs/IV/other_models.md index 5efd561..ead17d6 100644 --- a/docs/IV/other_models.md +++ b/docs/IV/other_models.md @@ -4,11 +4,12 @@ Another important representation of the hyperbolic plane is the **[Beltrami–Klein model](https://en.wikipedia.org/wiki/Beltrami%E2%80%93Klein_model)**, also known as the projective model of hyperbolic geometry. Unlike the Poincaré disk model, the Beltrami–Klein model is not [conformal](https://en.wikipedia.org/wiki/Conformal_map), meaning it does not preserve angles. However, it offers other advantages, particularly in how it represents geodesics. -In one of the [earlier chapters](I\basic-mathematics-in-the-poincare-disk-model.md), we introduced the Poincaré disk model, derived by projecting the upper sheet of a two-sheeted [hyperboloid](https://en.wikipedia.org/wiki/Hyperboloid) onto the unit disk in the plane $z = 0$. The Beltrami–Klein model is constructed in a similar way, but instead of projecting onto the plane $z = 0$, we project the upper sheet of the hyperboloid onto the plane $z = 1$. This subtle change leads to a model with distinct geometric properties. +In one of the [earlier chapters](I/basic-mathematics-in-the-poincare-disk-model.md), we introduced the Poincaré disk model, derived by projecting the upper sheet of a two-sheeted [hyperboloid](https://en.wikipedia.org/wiki/Hyperboloid) onto the unit disk in the plane %%z = 0%%. The Beltrami–Klein model is constructed in a similar way, but instead of projecting onto the plane %%z = 0%%, we project the upper sheet of the hyperboloid onto the plane %%z = 1%%. This subtle change leads to a model with distinct geometric properties. This [animation](https://www.youtube.com/watch?v=9D9AAcbflbU) illustrates the relationship between the Beltrami–Klein and the Poincaré disk models beautifully. You can also observe the differences between the two models in the image below: + ![alt text](image.png) ### Key Characteristics @@ -25,12 +26,12 @@ This is in contrast to the Poincaré disk model, which **is conformal**, preserv One of the convenient features of these two models is that it's easy to **convert a point from the Poincaré disk model to the Beltrami–Klein model**, and vice versa. Let: -- $\mathbf{p} = (p_x, p_y)$ be the coordinates of a point in the Poincaré disk model, with $\|\mathbf{p}\| < 1$. -- $\mathbf{k} = (k_x, k_y)$ be the coordinates of a point in the Beltrami–Klein model, with $\|\mathbf{k}\| < 1$. +- %%\mathbf{p} = (p_x, p_y)%% be the coordinates of a point in the Poincaré disk model, with %%\|\mathbf{p}\| < 1%%. +- %%\mathbf{k} = (k_x, k_y)%% be the coordinates of a point in the Beltrami–Klein model, with %%\|\mathbf{k}\| < 1%%. #### From Poincaré to Beltrami–Klein -The mapping $\mathbf{p} \mapsto \mathbf{k}$ is given by: +The mapping %%\mathbf{p} \mapsto \mathbf{k}%% is given by: $$\mathbf{k} = \frac{2\,\mathbf{p}}{1 + \|\mathbf{p}\|^2}.$$ @@ -38,7 +39,7 @@ This formula ensures that points in the Poincaré disk are sent to corresponding #### From Beltrami–Klein to Poincaré -Conversely, the mapping $\mathbf{k} \mapsto \mathbf{p}$ is: +Conversely, the mapping %%\mathbf{k} \mapsto \mathbf{p}%% is: $$\mathbf{p} = \frac{\mathbf{k}}{1 + \sqrt{1 - \|\mathbf{k}\|^2}}.$$ @@ -58,20 +59,22 @@ This model is [conformal](https://en.wikipedia.org/wiki/Conformal_map), like the ### Key Characteristics -![example](https://en.wikipedia.org/wiki/Poincar%C3%A9_half-plane_model#/media/File:Poincare_halfplane_heptagonal_hb.svg) +![pic](Poincare_halfplane_heptagonal_hb.svg) + +[Source](https://en.wikipedia.org/wiki/Poincar%C3%A9_half-plane_model#/media/File:Poincare_halfplane_heptagonal_hb.svg) - **Geodesics** in the half-plane model are either: - **Vertical straight lines**, or - - **Semicircles** centered on the x-axis (i.e., with their centers on the boundary \$y = 0\$). + - **Semicircles** centered on the x-axis (i.e., with their centers on the boundary %%y = 0%%). - **Hyperbolic distances** are different from Euclidean distances. The infinitesimal hyperbolic metric is given by: $$ds^2 = \frac{dx^2 + dy^2}{y^2},$$ - meaning that distances increase rapidly as one moves closer to the boundary at \$y = 0\$. + meaning that distances increase rapidly as one moves closer to the boundary at %%y = 0%%. -- The boundary \$y = 0\$ is **not part of the hyperbolic plane**, but represents "points at infinity," much like the boundary circle in the Poincaré disk model. +- The boundary %%y = 0%% is **not part of the hyperbolic plane**, but represents "points at infinity," much like the boundary circle in the Poincaré disk model. ### Conversion from the Disk Model @@ -79,7 +82,7 @@ There exists a Möbius transformation that maps the Poincaré disk model to the $$z \mapsto i \cdot \frac{1 + z}{1 - z},$$ -where $z \in \mathbb{C}$, representing a point in the unit disk. This transformation preserves angles and maps the unit circle (disk boundary) to the real line (the boundary of the upper half-plane), while the interior of the disk maps to the upper half-plane. +where %%z \in \mathbb{C}%%, representing a point in the unit disk. This transformation preserves angles and maps the unit circle (disk boundary) to the real line (the boundary of the upper half-plane), while the interior of the disk maps to the upper half-plane. ## Gnomonic Projection Model @@ -87,4 +90,6 @@ The **[gnomonic projection model](https://en.wikipedia.org/wiki/Gnomonic_project I don't find a lot of documentation on this model online, but I have a [website](https://geometricolor.wordpress.com/2018/11/04/various-projections-of-hyperbolic-kaleidoscopic-images/) that might help. -https://github.com/user-attachments/assets/23b0f337-2429-4373-aad7-e0cc986aa4b7 +![file](439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/23b0f337-2429-4373-aad7-e0cc986aa4b7) diff --git a/docs/LICENCE b/docs/LICENCE new file mode 100644 index 0000000..e72bfdd --- /dev/null +++ b/docs/LICENCE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. \ No newline at end of file diff --git a/docs/README.md b/docs/README.md new file mode 100644 index 0000000..7f9bd31 --- /dev/null +++ b/docs/README.md @@ -0,0 +1,162 @@ + + +
+ +[![Contributors][contributors-shield]][contributors-url] +[![Forks][forks-shield]][forks-url] +[![Stargazers][stars-shield]][stars-url] +[![Issues][issues-shield]][issues-url] +[![License][license-shield]][license-url] + +
+ + +
+
+ +

+
+ A Non-Euclidean Rendering Engine. +

+
+ +--- + +**Hyper** is an experimental engine for visualizing **non-Euclidean geometry**, starting with the **Hyperbolic 2D Plane** and extending into hybrid 3D space. It renders an infinite world, offering an educational, interactive view of **hyperbolic tilings** and **maze algorithms**. + +## Quickstart + +Clone the repository + +```bash +git clone https://github.com/cocosol007/hyper.git +cd hyper +``` + +### 3D + +To run the 3D view, run the command + +```bash +./gradlew run +``` + +![filename](441708765-5156987d-9099-42a6-9bd4-1a86abcd819e.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/5156987d-9099-42a6-9bd4-1a86abcd819e) + +#### 3D Klein model + +To run the 3D Klein model view, run the command + +```bash +./gradlew run --args="klein" +``` + +![filename2](441708869-b18b1862-54cd-4e70-bc3e-eb668aba2c67.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/b18b1862-54cd-4e70-bc3e-eb668aba2c67) + +#### 3D Gnomonic model + +To run the 3D Gnomonic model view, run the command + +```bash +./gradlew run --args="gnomonic" +``` + +![filename3](441708927-bc754d07-b1c2-435d-b459-7e679d5f27de.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/bc754d07-b1c2-435d-b459-7e679d5f27de) + +#### Ray-Caster Maze + +To run the RayCaster maze, run the command + +```bash +./gradlew runRayCaster +``` + +![filename4](435248313-cd564d2c-b59d-4107-a9d4-a5095251b5a3.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/cd564d2c-b59d-4107-a9d4-a5095251b5a3) + +### Poincaré and Beltrami–Klein disk model + +To run the 2D Poicaré disk model, run the command + +```bash +./gradlew run2D --args='poincare' +``` + +To run the 2D Klein model, run the command + +```bash +./gradlew run2D --args='Klein' +``` + +![filename5](435471805-cd1cf6c3-3550-4b40-a5ad-6ffeced9316c.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/cd1cf6c3-3550-4b40-a5ad-6ffeced9316c) + +### Gnomonic projection + +To run the 2D Gnomonic projection model, run the command + +```bash +./gradlew run2D --args='gnomonic' +``` + +![filename6](439980796-23b0f337-2429-4373-aad7-e0cc986aa4b7.mp4 ':include :type=iframe') + +[Source](https://github.com/user-attachments/assets/23b0f337-2429-4373-aad7-e0cc986aa4b7) + +## Documentation + +### 0. Project Setup + +- A. [How to Run the Project](running-the-project.md) +- B. [How to contribute](.github/CONTRIBUTING.md) +- C. [What for?](what_for.md) + +### I. Foundations in Hyperbolic Geometry + +- A. [Introduction](I/introduction.md) +- B. [Poincaré Disk Model](I/basic-mathematics-in-the-poincare-disk-model.md) +- C. [Isometries](I/isometries.md) + +### II. Tessellations + +- A. [Introduction to Tessellation](II/introduction_to_tesslation.md) +- B. [Coordinate System](II/coordinates_system.md) +- C. [Implementation](II/implementation.md) + +### III. 3D Rendering + +- A. Ray-Caster Maze (WIP) +- B. [Visual effects](III/3d-effects.md) + +### IV. In-Depth Explorations + +- A. [Other Models](IV/other_models.md) + +## Licence + +See all about our license [here](LICENCE.md) + +![GPL3](https://upload.wikimedia.org/wikipedia/commons/c/cb/GPLv3_Logo_filled.png) + +## Contributors + +[![Contributeurs](https://contrib.rocks/image?repo=cocosol007/hyper)](https://github.com/cocosol007/hyper/graphs/contributors) + +[contributors-shield]: https://img.shields.io/github/contributors/cocosol007/hyper.svg?style=for-the-badge +[contributors-url]: https://github.com/cocosol007/hyper/graphs/contributors +[forks-shield]: https://img.shields.io/github/forks/cocosol007/hyper.svg?style=for-the-badge +[forks-url]: https://github.com/cocosol007/hyper/network/members +[stars-shield]: https://img.shields.io/github/stars/cocosol007/hyper.svg?style=for-the-badge +[stars-url]: https://github.com/cocosol007/hyper/stargazers +[issues-shield]: https://img.shields.io/github/issues/cocosol007/hyper.svg?style=for-the-badge +[issues-url]: https://github.com/cocosol007/hyper/issues +[license-shield]: https://img.shields.io/github/license/cocosol007/hyper.svg?style=for-the-badge +[license-url]: https://github.com/cocosol007/hyper/blob/main/LICENCE diff --git a/docs/_coverpage.md b/docs/_coverpage.md new file mode 100644 index 0000000..0707d4d --- /dev/null +++ b/docs/_coverpage.md @@ -0,0 +1,4 @@ + + +> A Non-Euclidean Rendering Engine. + diff --git a/docs/_navbar.md b/docs/_navbar.md new file mode 100644 index 0000000..27441b3 --- /dev/null +++ b/docs/_navbar.md @@ -0,0 +1,28 @@ + + +* [Home](README.md) +* [O. Project Setup](running-the-project.md) + + * [A. How to Run the Project](running-the-project.md) + * [B. How to contribute](.github/CONTRIBUTING.md) + * [C. What for?](what_for.md) + +* [I. Foundations in Hyperbolic Geometry](I/introduction.md) + + * [A. Introduction](I/introduction.md) + * [B. Poincaré Disk Model](I/basic-mathematics-in-the-poincare-disk-model.md) + * [C. Isometries](I/isometries.md) + +* [II. Tessellations](II/introduction_to_tesslation.md) + + * [A. Introduction to Tessellation](II/introduction_to_tesslation.md) + * [B. Coordinate System](II/coordinates_system.md) + * [C. Implementation](II/implementation.md) + +* [III. 3D Rendering](III/3d-effects.md) + + * [B. Visual effects](III/3d-effects.md) + +* [IV. In-Depth Explorations](IV/other_models.md) + + * [A. Other Models](IV/other_models.md) \ No newline at end of file diff --git a/docs/complex_numbers.md b/docs/complex_numbers.md index 1fa5e56..9e9500b 100644 --- a/docs/complex_numbers.md +++ b/docs/complex_numbers.md @@ -4,28 +4,28 @@ Complex numbers are a fundamental tool in mathematics, allowing us to extend the ## Definition -A complex number is a number of the form $a + bi$, where $a$ and $b$ are real numbers and $i$ is the imaginary unit, which satisfies $i^2 = -1$. The real part of the complex number is $a$, and the imaginary part is $b$. +A complex number is a number of the form %%a + bi%%, where %%a%% and %%b%% are real numbers and %%i%% is the imaginary unit, which satisfies %%i^2 = -1%%. The real part of the complex number is %%a%%, and the imaginary part is %%b%%. ## Properties Complex numbers have many useful properties, including: -- **Addition**: Complex numbers can be added by adding the real and imaginary parts separately: $(a + bi) + (c + di) = (a + c) + (b + d)i$. -- **Multiplication**: Complex numbers can be multiplied by multiplying the real and imaginary parts separately, and then combining the results: $(a + bi) \times (c + di) = (ac - bd) + (ad + bc)i$. -- **Conjugation**: The complex conjugate of a complex number $a + bi$ is $a - bi$, which is obtained by changing the sign of the imaginary part. +- **Addition**: Complex numbers can be added by adding the real and imaginary parts separately: %%(a + bi) + (c + di) = (a + c) + (b + d)i%%. +- **Multiplication**: Complex numbers can be multiplied by multiplying the real and imaginary parts separately, and then combining the results: %%(a + bi) \times (c + di) = (ac - bd) + (ad + bc)i%%. +- **Conjugation**: The complex conjugate of a complex number %%a + bi%% is %%a - bi%%, which is obtained by changing the sign of the imaginary part. ## Geometry Complex numbers have a natural connection to geometry, as they can be used to represent points and vectors in the complex plane. In particular, complex numbers can be used to: -- **Represent points**: A point in the complex plane can be represented by a complex number $a + bi$, where $a$ is the x-coordinate and $b$ is the y-coordinate. +- **Represent points**: A point in the complex plane can be represented by a complex number %%a + bi%%, where %%a%% is the x-coordinate and %%b%% is the y-coordinate. - **Perform rotations**: Multiplying a complex number by a complex number of modulus 1 (i.e. a unit complex number) rotates the point in the complex plane by the angle of the unit complex number. - **Perform translations**: Adding a complex number to another complex number translates the point in the complex plane by the amount of the added complex number. Two other properties of complex numbers are useful in geometry: -- **Modulus**: The modulus of a complex number $a + bi$ is its distance from the origin in the complex plane, and is given by $|a + bi| = \sqrt{a^2 + b^2}$. -- **Argument**: The argument of a complex number $a + bi$ is the angle between the real and imaginary parts, and is given by $\arg(a + bi) = \tan^{-1}(\frac{b}{a})$. +- **Modulus**: The modulus of a complex number %%a + bi%% is its distance from the origin in the complex plane, and is given by %%|a + bi| = \sqrt{a^2 + b^2}%%. +- **Argument**: The argument of a complex number %%a + bi%% is the angle between the real and imaginary parts, and is given by %%\arg(a + bi) = \tan^{-1}(\frac{b}{a})%%. -> [!note] +> Note: > For a better representation of complex numbers, see a well explained [youtube video](https://www.youtube.com/watch?v=HrvEkftPZpw). diff --git a/docs/index.html b/docs/index.html new file mode 100644 index 0000000..65cb51f --- /dev/null +++ b/docs/index.html @@ -0,0 +1,50 @@ + + + + + + + + + + + + + + +
+ + + + + + + + + + + + + + + + + + diff --git a/docs/running-the-project.md b/docs/running-the-project.md index 2529828..fee116a 100644 --- a/docs/running-the-project.md +++ b/docs/running-the-project.md @@ -10,12 +10,12 @@ Before starting, make sure you have: ## Installation 1. **Clone the project** - ```sh + ```bash git clone https://github.com/CoCoSol007/hyper.git cd hyper ``` 2. **Grant execution permission to the Gradle wrapper (Linux/Mac)** - ```sh + ```bash chmod +x gradlew ``` @@ -24,7 +24,7 @@ Before starting, make sure you have: ### Using the Gradle Wrapper (recommended) - **On Linux/Mac**: - ```sh + ```bash ./gradlew run ``` - **On Windows**: @@ -36,21 +36,21 @@ Before starting, make sure you have: You can use the command: -```sh +```bash gradle run ``` ## Other Useful Commands - **Build the project**: - ```sh + ```bash ./gradlew build ``` - **Clean generated files**: - ```sh + ```bash ./gradlew clean ``` - **Run tests**: - ```sh + ```bash ./gradlew test ```