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Keynote Presentation

My first keynote presentation, at the CAD'24 conference in Eger (Hungary). It is mostly based on our recent survey on multi-sided surface representations, and there are also a few slides on the interior control structure to be presented at SMI'24 in Detroit.

Last update: 2024.07.06.

Interior Control Structure for Multi-Sided Patches

A paper written for the SMI'24 conference, on how to create a unified control structure for complex multi-sided surfaces based on (a variation of) the medial axis of its curved domain. Published in Computers and Graphics (open access).

I also presented the ideas in this paper and the one from last year's SMI conference at the Dagstuhl geometric modeling conference.

Last update: 2024.06.07.

Acorn Model

A writeup on a fun side project: modeling an acorn-shaped container for phase change materials. I have also created a real test object with a filament-based 3D printer.

2024.11.18.: The first mass-produced model!

Last update: 2024.04.28.

Multi-Sided Survey and Other Papers

Our survey on genuine multi-sided patches is published, at last, in the Paul de Casteljau special issue of Computer Aided Geometric Design (open access).

We have also written two other papers for a local conference: one on the exact refinement of GB(S) patches, and another one on using quadratic GB patches to create a smooth interpolation of arbitrary topology (quad)meshes. (For the latter see also the associated code and my slides.)

Last update: 2024.04.10.

Kirigami Snowflake

Step-by-step instructions on making a paper snowflake from a rectangular piece of paper. Nothing new, I guess, but saves me the time looking it up on the net every year.

Last update: 2023.12.15.

Intuitive Interior Control for Multi-Sided Patches with Arbitrary Boundaries

A paper that was originally an idea written down in a four-line note. After presenting it at Curves & Surfaces, I have added a bit more stuff and finally it appears in (virtual) print.

It is published in the Computers-Aided Design and Applications journal; there is also a short version for the proceedings of the CAD'23 conference.

Last update: 2023.06.20.

Constrained Modeling of Multi-Sided Patches

Our newest paper written for the SMI'23 conference, on how to create ribbon surfaces and how to modify them using control vectors while retaining continuous connections to adjacent surfaces. Published in Computers and Graphics (open access). See some related slides here.

Last update: 2023.06.14.

Rainbow Snake Puzzle

My very own puzzle game in the style of the magnetic puzzles developed by SmartGames (also in text format). All supporting code for experimenting was written in Prolog, and the ImageMagick commands for creating the images were generated by AWK scripts. (The scales are generated by a hand-made 24x24 pixel pattern.)

There is also a list of all 92 solutions (only 26 of which are substantially different, because of symmetry), and the table of correspondences and solvability.

Last update: 2023.04.16.

Origami Envelope

An origami envelope made from A4 (or other 1:sqrt(2)) paper. The result has area 2 sqrt(2) / 16 ~ 0.24; the ratio of its edges is around 1.3. If you want to actually insert something, put it under the bottom flap after step 3.

Last update: 2023.03.13.

Tessellation of Zheng-Ball patches

A short paper on how to tessellate Zheng-Ball patches. See also my implementation.

Last update: 2023.02.06.

Thai Special Letters

Some letters in Thai occur in only a handful of common words. Here's a list of these rare letters, with a few words using them.

Last update: 2023.01.31.

Twisting Fold

A printable diagram (also in PDF) of Jun Maekawa's "boko-bako" (凹箱, or "concave box"), containing my favorite twisting fold. (Bold lines are mountain folds; the first step folds everything except the lines at the top.)

Last update: 2023.01.16.

Origami Cubes

My first (unit) origami design. There are many ways to make cubes without creases on the faces, there is e.g. John Montroll's from 1 square paper, or Miyuki Kawamura's from 6. This is one using 3 squares - it is so simple, that someone else must have done it before.

I have also done a 2-unit variation, originally asymmetric, but there is also a symmetric version using alternative steps.

Another 2-unit cube is folded from half-squares. It is somewhat small (the edges are 1/6 of the square's), but its surface area is 1/6 of that of the total used paper, which is comparable to the other ones (3-unit: 2/9, 2-unit: 3/16).

Finally, I have found a box - an open cube - also so simple that it must be already known. There are also step-by-step instructions (with some additional creases for simplicity). A perfectly matching lid can be made from a square of the same size. If you disregard the first two steps, the lid is just a variation on the box itself, where the base has edge length 1/2 instead of 1/3. This is a trade-off between height and volume: the lid-type variant has larger volume but smaller height; maximum volume is achieved when the base has edge length 2/3, but then the "walls" are a bit too low.

Last update: 2022.10.31.

Origami Pocket

A sturdy pocket for storing small things, made from A4 (or other 1:sqrt(2)) paper. The last step has 3 variations:

Last update: 2022.10.31.

Hybrid Patch

My presentation at the Curves & Surfaces conference (actually presented by M. Vaitkus, due to unforeseen circumstances). Multi-sided patches usually either have arbitrary boundary constraints (transfinite interpolation surfaces) or natural interior control (generalized Bézier patches), but not both - until now!

Last update: 2022.06.22.

Circular Parameterization

A fun presentation on the (somewhat strange) idea that you can actually use a simple circle as the domain for a multi-sided surface. The parameterization has all the good properties, and is suitable for cases with periodic boundaries. There is also actual Julia code supplied in the paper.

Last update: 2022.06.09.

Coons Patch Generalizations

A talk I have given at the CSF conference on generalized barycentric coordinates in Ascona, Switzerland. This nicely summarizes my previous work, including the C0 Coons, Composite ribbon, Midpoint, Midpoint Coons, Generalized Coons patches. There is also a technical report with roughly the same contents.

Last update: 2022.06.04.

What Does It All Mean?

An (unofficial) Hungarian translation of Thomas Nagel's introduction to interesting philosophical questions, for the 13th birthday of my goddaughter.

Last update: 2022.05.15.

Hebrew Memos

All the words I have learned from the (Japanese) textbook "CD Express Modern Hebrew" (by Keiko Yamada) and all the dialogues from the book. Also some grammar notes (in Hungarian). About using the dictionary file, see the snippet page.

Last update: 2022.05.12.

Prolog Book

A book version of my Prolog lessons largely based on the first part of Ivan Bratko's wonderful Prolog Programming for Artificial Intelligence.

You can also download the example code.

Clone the repository with Git:

git clone https://github.com/salvipeter/prolog-konyv.git
Last update: 2022.03.27.

French Words

All the words I learned from the classic (1938) Teach Yourself French textbook (with meanings in Hungarian). Also here are all the readings from the book.

Last update: 2022.02.28.

Bézier Extraction Matrices

A short memo on how to use Bézier extraction matrices. See also my implementation.

Last update: 2022.02.04.

Bézier Proximity Curves

A paper on a simple method to generate a class of proximity curves in standard Bézier representation. See also my testbed environment.

Last update: 2022.02.03.

Tcl Memos

Some memos I've taken while reading the Tcl manual.

Last update: 2022.01.27.

Mesh Approximation with I-Patches

A sequel to our I-patch paper, this time using this implicit surface representation to approximate triangle meshes, with adaptive refinement.

It is published in the Computers-Aided Design and Applications journal; there is also a short version for the proceedings of the CAD'21 conference.

I also gave a talk about both papers at the Dagstuhl Geometric Modeling seminar.

Last update: 2022.01.22.

Yoruba Notes

Some grammar notes I took while learning Yoruba. There is also a list of words (and also dialogues/sentences) from Colloquial Yoruba (Schleicher) and the wonderful (but very difficult) Teach Yourself Yoruba (Rowlands). All the above is in Hungarian.

Last update: 2022.01.07.

Programming for Hedgehogs

A paper showing how homoiconicity is (almost) the only thing you need to have a great programming language. There is no novelty here, but I wanted to write a Common Lisp tutorial, and this seemed to be a nice topic. It also provided an opportunity to line up some of my favorite books (mostly, but not exclusively, on programming).

Last update: 2021.12.29.

Shape Operator

A summary of some important facts about the shape operator and the embedded Weingarten map, both in the context of parametric and implicit surfaces.

Last update: 2021.11.10.

Generalized B-spline Patches

Our new paper on the extension of the Curved Domain Bézier patches to B-spline boundaries, published in the Computer Aided Geometric Design journal.

Last update: 2021.06.09.

Prolog Lessons

A short series of lessons on Prolog and general programming, which I wrote for a friend of mine (in Hungarian). Largely based on the first part of Ivan Bratko's wonderful Prolog Programming for Artificial Intelligence, but also contains some other interesting extended examples.

Clone the repository with Git:

git clone https://github.com/salvipeter/prolog-leckek.git
Last update: 2021.05.29.

εκ-curves

A paper written in cooperation with K.T. Miura & co., about an extension of κ-curves (see also my implementation in Julia). After a failed attempt at SIGGRAPH Asia, it is now published open access in The Visual Computer journal; on the homepage there is also a demo video with my narration. And it is my first paper with a photo!

Last update: 2021.05.19.

Plants, Grammars, Automata and Beavers

I tried to sum up a few interesting topics in generative grammar & automata theory (in Hungarian), also including Prolog code for simulating Turing machines, and generating plants with Lindenmayer systems.

Read the HTML or get the latest MarkDown source with Git:

git clone https://github.com/salvipeter/formalis.git
Last update: 2021.04.07.

BibTeX

Correct BibTeX entries for my publications.

Clone the repository with Git:

git clone https://github.com/salvipeter/bibtex.git
Last update: 2021.03.03.

WAIT'21 Papers

Two new papers for the WAIT conference. The first one is on how to edit the interior of transfinite interpolation surfaces using displacement blends, See also my sample implementation.

The second paper is about generating good quality meshes for implicit surfaces, using my C0 Coons patch. (The latter one is a spin-off of our latest work on I-patches.)

Last update: 2021.02.01.

Nim Memos

Some memos I've taken while reading the Nim manual.

Last update: 2020.12.09.

Thai Words

All the words I learned from the Japanese textbook "New Express Plus Thai" (with meanings in Hungarian). Also here are all the dialogues from the book.

Added the words from "Teach Yourself Thai" by D. Smyth.

Added the words from "Colloquial Thai" by J. Moore & S. Rodchue.

Last update: 2020.09.10.

Persian Poems

A collection of Persian quatrains that I translated into metric Hungarian verse. Transliterations of the poems are also provided. The poems are taken from a wide range of poets, from the 10th to the 20th century.

This booklet also contains an introduction to Persian pronounciation, and the basics of metric poetry, as well as a few biographic notes on the poets.

Last update: 2020.06.10.

CAD Conversion of Multi-Sided Surfaces

At last we were able to publish our paper on how to convert various multi-sided patches into rational Bézier form, with a special emphasis on the quality of the generated control net.

It is published in the Computers-Aided Design and Applications journal; there is also a short version for the proceedings of the CAD'20 conference.

See also the related tensor conversion snippet, and the narrated presentation.

Last update: 2020.05.25.

Implicit surfaces

Our new paper submitted to the SMI 2020 conference, which shows how a classic implicit surface representation, the I-patch, can be used for non-trivial modeling tasks, including setback vertex blends and polyhedral design.

It is published in the Computers & Graphics journal; see also the related implicit fitting snippet.

Last update: 2020.05.19.

Tajik Keyboard Layout for Emacs

An Emacs implementation of the Tajik YQUKEN keyboard layout (a modification of the cyrillic JCUKEN layout). There is also a version for IBus-m17n, put it in your ~/.m17n.d/ directory. You may also need to un-blacklist it in /usr/share/ibus-m17n/default.xml, by adding the following snippet at the end:

	<engine>
		<name>m17n:tg:kbd</name>
		<rank>1</rank>
	</engine>
Last update: 2020.05.19.

VT100 Control Sequences

A memo on the VT100 control sequences for my students, with which you can (i) clear the screen, (ii) move the cursor, (iii) change the formatting/colors. X11-specific window-controlling sequences are also touched upon. (In Hungarian.)

Last update: 2020.05.15.

YINSH Board

PostScript YINSH board printable on A4 paper (also in PDF). Print two copies and glue them together. Pieces should have a radius of less than a half inch (~1.3 cm).

Last update: 2020.03.30.

Battle Sheep

Board tile cut-outs for Battle Sheep (a.k.a. Splits), in PostScript and PDF format.

Last update: 2020.03.16.

Curved Domain Bézier Patches

Our new paper on the extension of Concave Generalized Bézier patches to curved domains, published in the Computer Aided Geometric Design journal.

Last update: 2020.02.27.

Books that Make You Smarter

A list (and minimal introduction) of some of my favourite books on programming, sorted by programming language.

Download it in Org-mode text or in HTML.

Last update: 2020.02.09.

C0 Coons Patch

A (very) short paper on the multi-sided generalization of the C0 Coons patch. It draws on the same idea as the CR patch, but does not need normal information at the boundaries. A simple, lightweight patch when C0 continuity with adjacent patches is sufficient. See also my sample implementation.

Last update: 2020.01.30.

Catchup Board

A "dual" Catchup board printable on A4 paper (also in PDF). The size is just right to play with Go stones (triangle edges are 1" long), but you will need smaller markers for the scoring track. The game is played by two players with black and white Go stones. The rules are simple:

Last update: 2019.12.28.

3-sided Dice

There are dice of various number of sides. But is there a 3-sided die? The answer is YES! My original idea was that it should have 3 faces, and should be symmetrical. The intersection of three spheres is like that. Place the center of the spheres on the vertices of an equilateral triangle, and make their radii somewhat larger than the side of the triangle (how much larger depends on how "fat" you want the die to be).

Then I found out that there are 3-sided dice in existence, but they have more than 2 faces: these can be constructed as the intersection of three planes (an extruded equilateral triangle) with a sphere.

I have printed both model types (with supports, without supports), the conclusion is that my design rolls better when fat, but the other design rolls even better.

Last update: 2019.11.26.

Dara Board

Dara is a Nigerian board game similar to Nine Men's Morris (but much more complex). Variations of it are played throughout West Africa. I have summarized the rules, and created a simple A4 PostScript board (also in PDF). It is the perfect size to play with checkers pieces.

Last update: 2019.10.23.

DVONN Boards

PostScript DVONN boards printable on A4 paper:

I use the last one scaled 1:sqrt(2); it can be printed on two A4 sheets with this half-board (EPS, PDF), the result looks like this

Last update: 2019.10.06.

Thai Transliteration

My transliteration system for Thai. It only uses normal ASCII letters, but gives back the exact sounds (including tones).

Last update: 2019.10.05.

Origami Octahedron

A simple regular octahedron foldable from half of any 1:sqrt(2) sized paper (e.g. A- and B-series).

Last update: 2019.09.28.

Gyges Board

A simple EPS board (also in PDF) for the Gyges board game. Each square is about 3 cm wide, so stacked checkers can be used as pieces. Also, here are the rules summarized in English and in Hungarian.

Last update: 2019.09.06.

Thai Script

All the letters of the Thai alphabet with different styles (fonts), and a useful two-page summary at the end (in Hungarian).

Last update: 2019.08.13.

Marrakech Set

A simple EPS board for the Marrakech board game. Each square is about 2.5 cm wide, so the carpets should be 2.5cm x 5cm, you can make 18 of them from a standard 15cm square origami paper. Also, here are the rules summarized in Hungarian.

See two photos of my travel Marrakech set: the box and while playing. (Money is represented by black & white discs from a paper Go set; Assam is a Shogi pawn.)

Last update: 2019.06.21.

Sanskrit Memos

My notes on Sanskrit grammar I took while working through The Cambridge Introduction to Sanskrit (in Hungarian). Also, there is a vocabulary of all the words appearing in the book; and I have compiled a list of errors.

Last update: 2019.06.20.

Origami Tetrahedra

A simple regular tetrahedron foldable from any 1:sqrt(2) sized paper (e.g. A- and B-series), and a right angle tetrahedron foldable from half of a square.

If you take 4 of the right angle tetrahedra, and one regular tetrahedron, you can also build a cube! The smaller sides of the papers should have a ratio of 1:sqrt(3), so if you fold the right angle tetrahedra from a paper of size (1,2), the regular tetrahedron should be folded from a paper of size (sqrt(3),sqrt(6)).

There is an alternative version of the right angle tetrahedron, foldable from a square paper. For the above construction to work, the smaller side of the regular tetrahedron should be 3-sqrt(3).

Last update: 2019.05.29.

Curriculum Vitae

My CV in European (EuroPass) and in Hungarian format.

Last update: 2019.03.08.

S-patch Papers

Two papers related to S-patches, both presented at local conferences: G1 hole filling with S-patches made easy (KÉPAF'19), which also has a nice poster (also in SVG), and On the CAD-compatible conversion of S-patches (WAIT'19), with slides.

See also the related biharmonic S-patch snippet.

Last update: 2019.02.20.

Bridge Bidding System

The conventions of our SAYC-based bidding system (in Hungarian), converted from reStructured Text format, with internal links for easy browsing.

Get the latest source with Git:

git clone https://github.com/salvipeter/dosszioz.git
Last update: 2018.12.28.

Vietnamese Alphabet

A short memo on the spelling and pronunciation of Vietnamese (in Hungarian). Also in HTML format.

Last update: 2018.12.01.

XiguaQi Board

A board for playing XiguaQi. This is a simple two-player game where players move their pieces along the lines to adjacent intersections. Initially the 6-6 pieces are on the lower (upper) half of the board, with the points of the central circle left empty. When a piece or a group of pieces has nowhere to go, it is removed from the board. The player who has less than 3 pieces loses.

Last update: 2018.11.27.

Bagh-chal Rule Variations

A short memo comparing different bagh-chal rules, including: Fox & Geese, Asalto, Catch the Hare and a few others.

There are also (minimal) printable boards for Bagh-chal and Fox & Geese / Asalto. The PDF versions can be downloaded here: Bagh-chal, Fox & Geese (no diagonals), Fox & Geese, Asalto.

For 16 Musashi I host a board I found on the internet - and also here are two paintings where it is played by children and by women.

Fanorona is a different kind of game, but uses a similar board, so I made the required modifications (EPS, PDF).

Last update: 2018.11.13.

Functional Programming Language Based on Combinatory Logic

I tried to organize my thoughts on functional programming languages, and wrote a memo/tutorial (in Hungarian) on how to create a very basic language based on combinatory logic.

Read the HTML or get the latest MarkDown source with Git:

git clone https://github.com/salvipeter/programnyelv.git
Last update: 2018.09.22.

Square Kufic Designs

Random Arabic phrases wrapped into a geometric design of Kufic script. The PBM files are just bitmaps, the larger PNGs also show the same phrase unwrapped and in standard (Naskh) script.

Open SesamePBMPNG
Time is Like a SwordPBMPNG
(my name)PBMPNG / Color PNG / Seal (password-protected)
(my wife's name)SVGPNG
Thank YouPBMPNG
KebabPBMPNG
Kufic ScriptPBMPNG
Merry ChristmasPBMPNG / Paper-cut
Indonesian LanguagePBM / Dotless versionPNG
FatimaPBMPNG

Last update: 2018.07.30.

Moroccan Mathematics

A (very) short presentation on Moroccan mathematics (in Arabic). This was a task for completing the Advanced 1 MSA course in Qalam wa Lawh, Rabat.

Last update: 2018.07.03.

Moroccan Arabic

A memo (in Hungarian) of the most important differences between the Moroccan dialect of Arabic and the "common denominator" spoken language (e.g. the one taught in Arabic Today).

Download it in Org-mode text or in HTML.

Last update: 2018.06.23.

Maximum Entropy

A short summary on the maximum entropy principle and its use for generalized barycentric coordinates (in Hungarian). See also my implementation.

Last update: 2018.06.16.

Concave Generalized Bézier Patches

Our new paper on the concave extension of Generalized Bézier patches, published in the Computers & Graphics journal, and presented at SMI 2018, winning best paper.

Last update: 2018.06.11.

Persian in 30 Pages

As an exercise, I have tried to write up a 30-page introduction to Persian grammar (in Hungarian), covering (almost) all the basic constructions, along with some worked out example texts. The goal was to create a document that can be read and understood with no previous knowledge of the language.

Download the PDF or get the latest LyX source with Git:

git clone https://github.com/salvipeter/gyorstalpalo.git
Last update: 2018.04.29.

Enhanced Generalized Bézier Patches

We have published a paper about enhancements and fixes of Generalized Bézier patches in the "In memoriam Gerald Farin" special issue of the CAGD journal.

I have also presented the results at the GMP 2018 conference.

Last update: 2018.04.12.

A Discrete Curve

A memo on how I found out the continuous representation of a discrete curve I used to doodle when I was a kid (in Hungarian). [Note that, while similar, this is not an astroid: drawing an astroid requires the "falling" line segment to be of constant length.]

Last update: 2018.03.10.

Urdu Poetry Primer

A two-page summary of the basics of Urdu poetry, concentrating on prosody and the ghazal form (in Hungarian).

Last update: 2018.01.19.

Turkish Memos

My notes on Turkish grammar I took while working through Lewis' Teach Yourself Turkish (in Hungarian). Also, there is a vocabulary of all the words appearing in the book.

Last update: 2018.01.04.

Arabic Today

I have recently bought the 2nd edition of "Arabic Today" (by John Mace), which is a unique Arabic textbook, as it first teaches the colloquial language, then moves on to the written language (normally it is the other way around). I have found this approach very nice, as the colloquial language does not impose such a burden on the learner, and the transition is also quite easy, using the short pronunciation as a base. The spoken language the book teaches is a kind of common educated language that is not specific to any one region, and can be used anywhere in the Arab world.

The book does have its faults - there are no translation exercises, and the audio is worthless (apart form the first three lessons, only some exercises have recordings). Also, it focuses on business/media vocabulary a bit too much for my taste. Still, it is the best textbook I know of.

You can find all the words (with Hungarian translations). I have found quite a few misprints and a few omissions, so I wrote up an errata (in English).

Last update: 2017.12.06.

Metres of the Poems in Faces of Love

A list of the metres of all poems in the book Faces of Love (a compilation of Persian poetry by three Shirazi poets, translated by Dick Davis). The metres are given also using Elwell-Sutton's numbering system.

Last update: 2017.09.15.

Midpoint Coons Patch

A fusion of two earlier patches (MP and GC), the Midpoint Coons patch boasts computational efficiency and interior control. Read all about it in our paper for the WAIT'17 conference. Also there is a nice set of slides (with a Star Trek reference).

Last update: 2017.01.31.

Introduction to Persian

I have worked trough all exercises in the 4th edition of "An Introduction to Persian" (by W. M. Thackston), which was a very nice experience. You can find all the words in the vocabulary lists (with Hungarian translations). I have bought the key for this textbook, but found that it had quite a lot of misprints and a few omissions, so I wrote up an errata containing all errors and typos I have found.

Last update: 2017.01.24.

Rust Memos

Some memos I've taken while reading the Rust manual.

Last update: 2016.12.29.

Hindi/Urdu Verb Forms

A table of Hindi and Urdu verb forms (in Hungarian).

Last update: 2016.11.22.

Interview

At the end of my 1-year stay in Hamamatsu, the Suzuki Foundation made a short interview with me about my research, life in Japan etc. (in Japanese).

Last update: 2016.09.12.

Log-Aesthetic Curves

A short review presentation on aesthetic curve representations, focusing on log-aesthetic curves.

Last update: 2016.07.28.

Fitting Generalized Bézier Surfaces

My first rejected paper! It was a short submission to the Pacific Graphics 2016 conference. While it does not have much theoretical contribution, I think it still does a good job as a technical report, so it deserves its place here.

The paper was polished a bit and re-submitted to a small local conference at our university (WAIT 2018). Thus the original version is removed.

Last update: 2016.07.21.

Midpoint Patch

Another new paper, this time for the bi-annual Hungarian conference, contrasting multi-sided representations with fullness control, and also introducing a very nice transfinite formulation, which we call the midpoint patch.

Last update: 2016.02.26.

Generalized Bézier Patches

A new paper on the multi-sided generalization of Bézier patches is accepted to the Eurographics 2016 conference, so it will be published in the Computer Graphics Forum journal.

I have already created some slides for the presentation.

Last update: 2016.02.02.

Koranic Arabic

I have worked trough all exercises of "An Introduction to Koranic and Classical Arabic" (by W. M. Thackston), which was a very nice experience. These are all the words in the vocabulary lists (with Hungarian translations). I have bought the key for this textbook, but found that it had quite a lot of errors, even though most exercises used sentences or passages from the Koran or from hadith literature, so I wrote up an errata containing all errors and typos I have found.

Last update: 2015.11.18.

Julia Memos

Some memos I've taken while reading the Julia manual.

Last update: 2015.10.30.

Bayesian Statistics Notes

A memo of the methods in the book "Introduction to Bayesian Statistics".

Last update: 2015.10.15.

Poems in "Chinese through Poetry"

I have collected all poems in "Chinese through Poetry", using simplified characters (TXT, PDF), and also all characters in the vocabularies. There is also a list of errors I've found.

Last update: 2015.10.03.

Italian Memos

All the words I have learned from the classic "Teach Yourself Italian" by K. Speight. There are also some grammar notes. About using the dictionary file, see the snippet page.

Last update: 2015.09.13.

DIY Love Letter

Printable cards for Seiji Kanai's Love Letter game in Hungarian and in English.

Last update: 2015.04.11.

Checkers/Draughts Rule Variations

A short memo comparing different checkers rules: Russian checkers (shashki), English draughts, tournament (or pool) checkers and international checkers.

There is also a minimal printable shashki board for A4 paper using 1 inch squares (EPS source).

2017.12.20.: A board with numbers is also available (PDF, EPS).

Last update: 2015.04.03.

Vim Memo

I'm a believer of Emacs, but every now and then I have to use the EviL editor. This is a brief guide on the essentials of movement and editing in vi/vim.

Here is the original Org mode file, and the generated HTML.

Last update: 2015.03.17.

Indonesian in 20 Pages

As an exercise, I've tried to write up a 20-page introduction to Indonesian grammar (in Hungarian), covering (almost) all the basic constructions, along with a worked out example text. The goal was to create a document that can be read and understood with no previous knowledge of the language.

Download the PDF or get the latest LyX source with Git:

git clone https://github.com/salvipeter/gyorstalpalo.git
Last update: 2015.02.13.

n-Patch Comparison and Poster

A comparison between the generalized Coons patch and our version of the Gregory patch was presented at the 10th Conference of the Hungarian Association for Image Processing and Pattern Recognition. This paper was accepted as a poster (PDF, Scribus) displayed on a fullHD display.

Last update: 2015.01.30.

Hindi Memos

All the words I have learned from "Teach Yourself Beginner's Hindi" (R. Snell), "Teach Yourself Hindi" (R. Snell), and "Living Language Hindi" (M. Bhat) - the latter lists containing only the words not appearing in the previous ones. There are also some grammar notes. About using the dictionary file, see the snippet page.

Last update: 2014.12.31.

Elementary Bridge Techniques

A summary of some elementary Contract Bridge techniques (in Hungarian): trump play, notrump play, and defensive leads and signals.

Last update: 2014.12.22.

Spanish Memos

All the words I have learned from the classic "Teach Yourself Spanish" by N. S. Wilson. There are also some grammar notes. About using the dictionary file, see the snippet page.

Last update: 2014.10.25.

G2 Surface Interpolation

A new paper on creating G2 Gregory patches over a curve network. It was presented at the Pacific Graphic 2014 Conference in Seoul, and it is published in the Computer Graphics Forum journal. A (less polished) previous version was presented at the Seventh Hungarian Conference on Computer Graphics and Geometry, 2014.

Last update: 2014.10.13.

My Favourite Knots

A list of my favourite knots, mostly found in Geoffrey Budworth's wonderful "The Knot Book" (and of course in the Ashley Book of Knots).

Last update: 2014.09.29.

Ribbon-based Transfinite Surfaces

After two years and three revisions, at last our paper is published in the Computer Aided Geometric Design journal.

Note: I have also presented this work at the GMP'15 conference in Lugano.

Last update: 2014.08.05.

Advanced Bridge Techniques

A summary of some advanced Contract Bridge techniques (elimination, throw-in, squeeze, trump/grand coup, Bath coup, Deschapelles coup) illustrated with examples (in Hungarian).

Get it in plain text or in PDF format.

Last update: 2014.07.28.

Hindi Numbers

A logical summary of how numbers are built up in Hindi.

Last update: 2014.06.11.

Persian Memos

All the words I have learned from "Teach Yourself Modern Persian" - both the wonderful 1971 version by John Mace, and the awful 2004 version by N. Farzad, the latter list containing only the words not appearing in the first. There are also some grammar notes. About using the dictionary file, see the snippet page.

Added the words from "An Introduction to Persian" by W. M. Thackston.

Last update: 2014.01.31.

Origami Introduction

I've done an origami workshop at an Asia-related event, and also created some slides to introduce the main concepts (in Hungarian).

Last update: 2014.01.29.

Korean Memos

These are my Korean wordlists. I have tried to learn Korean from quite a few books. The first was Teach Yourself Korean (M. Vincent & J. Yeon), then came the Elementary & Continuing Korean (R. King & J. Yeon), then I found the nice website of Sogang University, which included a few courses. I've also taken some grammar notes.

It was only much later when I realized that Korean is very easy to learn through Japanese. So I bought 文法をしっかり学ぶ韓国語 and 前田式韓国語中級文法トレーニング, and started it all over again (wordlist, grammar notes). About using the dictionary file, see the snippet page.

Last update: 2014.01.15.

IMA 2013 Conference Paper

Our paper "Transfinite surface interpolation over specific curvenet configurations" at the 14th IMA Conference on Mathematics of Surfaces.

Last update: 2013.09.17.

SCIM (and Emacs) Input Method Tables

A Greek (which is a port of the modified Emacs greek-babel input method), a Latin (that contains diacritical marks), a Russian (which is a port of the Emacs transliterated cyrillic input method), a Turkish (which is a prefix translation of the Emacs turkish-postfix input method - another Emacs input method mimics the (non-modified) characters of the Turkish Q layout), a Persian (which is a translation of the Emacs farsi-isiri-9147 input method), an Arabic, implementing the standard layout (image from Wikipaedia), and two Hungarian tables for the Smart Common Input Method (SCIM). Place these files in ~/.scim/user-tables, and don't forget to edit the icon path in the txt files. There is also an Emacs port of the SCIM JyutPing (Cantonese Big5) input method, and a postfix Yoruba input method for Emacs (not yet translated to SCIM).

Last update: 2013.12.28.

Go & the Japanese Language

My lecture on the game of go and the Japanese language, presented at the Japan Foundation office in Budapest. I have also created a 9x9 PostScript board for the students (also in PDF and with wood background), and one twice as large for the whiteboard using 40mm magnets (also in PDF).

Added: a 5x5 PostScript board for goro problem solving (also in PDF).

Added: a template for recording go games (碁罫紙) (19x19, A4 size).

Last update: 2013.07.15.

More Papers on Transfinite Surface Interpolation

Two recent papers: a longer one presented at the Hungarian KÉPAF 2013 conference, and a short paper for Eurographics 2013.

Last update: 2013.05.20.

Wedding Invitation

Our invitation card created in Scribus. There is also another version for our wedding party in Japan with an RSVP card.

Last update: 2013.03.21.

PhD Dissertation

My PhD dissertation on "Fair Curves and Surfaces", along with its synopsis (in English and in Hungarian), and the theses booklet (in English and in Hungarian). The main results are also illustrated in the (Hungarian) slides that I presented at the defense of my dissertation.

Last update: 2012.12.14.

Transfinite Surface Interpolation with Interior Control

A paper that will be published in the Graphical Models journal.

Last update: 2012.04.26.

New Papers on Transfinite Surface Interpolation

Two papers we've written for the Sixth Hungarian Conference on Computer Graphics and Geometry, 2012: 3D Shape Design Using Curve Networks with Ribbons, and New Schemes for Multi-sided Transfinite Surface Interpolation.

I have also given a talk on the latter topic at the International Workshop on New Trends in Applied Geometry held in Gazzada, Italy.

Last update: 2012.02.18.

My PGP Key

This is my public key for anyone who wants to send me secure data. You can import it to your keyring using GnuPG with gpg --import peter-salvi.pgp.

PGP Fingerprint: F069 3534 5174 7418 F532 5FD2 CF7A 4AA7 B89A BC28

GTalk/OTR Fingerprint: 01904A6A 78CB8BCB DDBEA30B E0274B8F FBBA3D95

ICQ/OTR Fingerprint: 4502CD10 404F82BC 89E4E9F3 10BDDB91 5B3B4264

MSN/OTR Fingerprint: EC68BEF1 DDB9319E B87D0B35 DF17EEA2 200DA5FE

Last update: 2011.10.13.

Transfinite Surface Interpolation over Irregular n-sided Domains

A paper we've written for the SPM2011 conference. It will be published in the CAD journal.

Last update: 2011.10.01.

Swahili in 20 Pages

As an exercise, I've tried to write up a 20-page introduction to Swahili grammar (in Hungarian), covering (almost) all the basic constructions, along with a worked out example text. The goal was to create a document that can be read and understood with no previous knowledge of the language.

Download the PDF (there is also a cheat sheet), or get the latest LyX source with Git:

git clone https://github.com/salvipeter/gyorstalpalo.git
Last update: 2011.07.30.

Configuring Gamepads under Linux

A description on configuring my cheap Kraun gamepad to work under Linux. It involves downloading various tools, hacking a kernel module and patching the SDL library - all in a day's work for a programmer!

Last update: 2011.05.08.

Swahili Memos

All the words I have learned from "Colloquial Swahili" (D. McGrath & L. Marten) and those I have learned from "Teach Yourself Swahili" (J. Russell) and those from "Living Language Swahili" (Kh. Mohamed & A. Mazrui), containing only the words not appearing in the previous lists. There are also some grammar notes. About using the dictionary file, see the snippet page.

2010.02.24.: The word list of "Colloquial Swahili" is complete.

2010.04.24.: The word list of "Teach Yourself Swahili" is complete.

2011.05.05.: The word list of "Living Language Swahili" is complete.

Last update: 2011.05.05.

Cantonese Words

All the words I have learned from "Colloquial Cantonese" (Keith S.T. Tong & Gregory James), along with Hungarian meanings and chinese characters (also in HTML version). There is another list in text or in HTML for "Teach Yourself Cantonese" (H. Baker & P. Ho), containing only the words not appearing in the first list. About using the dictionary files, see the snippet page.

2009.11.22.: The word list of "Colloquial Cantonese" is complete.

2011.03.24.: The word list of "Teach Yourself Cantonese" is complete.

Last update: 2011.03.24.

Indonesian Memos

All the words I have learned from "Teach Yourself Indonesian" (Ch. Bymes & E. Nyimas) and some grammar notes. About using the dictionary file, see the snippet page.

2011.02.07.: The word list of "Teach Yourself Indonesian" is complete.

Last update: 2011.02.07.

Arabic Memos

All the words I have learned and some grammar notes (HTML) I took (in Hungarian) while learning from "Teach Yourself Arabic" (J. R. Smart) and other sources, such as "Arabic - An Essential Grammar" (Faruk Abu-Chacra) and "A New Arabic Grammar of the Written Language" (J. A. Haywood & H. M. Nahmad). The words file also has a pattern search feature (written in Emacs Lisp).

Another ASCII-based dictionary contains all the words from the book "Teach Yourself Gulf Arabic" (J. Smart & F. Altorfer).

There is also yet another dictionary based on the words from the series العربية بين يديك (Arabic Between Your Hands). About using the dictionary file, see the snippet page.

Counting may be the most complex part of the Arabic language. Here is a short (Hungarian) memo with a few examples (also in HTML).

Last update: 2010.12.11.

What Makes a Programming Language Comfortable?

A few thoughts on what are the prerequisites for a comfortable programming language. Of course all of this is very subjective.

Last update: 2010.08.16.

Constrained Fairing of Freeform Surfaces

A paper I've written for the Fifth Hungarian Conference on Computer Graphics and Geometry, 2010 and the slides I've presented. It was also rewritten as a short paper for the SPM2010 conference (there is also a longer version).

Last update: 2010.05.28.

Installing VimClojure

A memo on how to install VimClojure.

Last update: 2010.04.06.

Scripting with CLISP

A memo on how to setup CLISP for writing scripts, along with a short example.

Last update: 2009.12.15.

Wubi - Pinyin Dictionary

A list that contains every (1-character) wubi code and maps them to their corresponding chinese character and pronounciation (in pinyin). There is a version with Unicode accents, and a two-column PDF.

This dictionary is automatically generated from the data files of my Wubi Practice program and the tonepy input method in Emacs.

Last update: 2009.11.09.

Compilation in Clojure

A memo on how to compile Clojure programs into JAR files.

Last update: 2009.06.06.

Fairing Posters

Two posters about my research, created with Scribus. Available in Scribus (first, second), EPS (first, second) and JPG (first, second) file formats.

Last update: 2009.05.20.

Ancient Greek Memos

All the words I have learned and some grammar notes (HTML) I took (in Hungarian) while learning from "Introduction to Attic Greek" (D. J. Mastronarde). This table contains sample words for practicing every declension and conjugation I (should) know (there is a filled version here, and also in PDF format). There is also a list of my solutions to the exercises of the book "Homeric Greek - A Book for Beginners" (C. Pharr). About using the dictionary file, see the snippet page.

Note: The Homeric Greek exercises are temporarily suspended.

Last update: 2008.12.26.

Mahjong Rules

A short memo (in Hungarian) on the rules of Chinese and Japanese mahjong, containing the most important words in both languages (also with romaji for Japanese).

Download it in TXT or in HTML.

Last update: 2008.11.18.

Slides on the ICFP'08 Contest

The slides of the presentation I've given on the ICFP'08 programming contest with my friend 黄涧石 at a Lisp seminar in Tokyo.

Download in English (PPT, PDF) or in Japanese (PPT, PDF).

Last update: 2008.11.17.

Cybook Thumbnails

I've created a few (four-gray) thumbnails for some books I've uploaded to my Cybook, using this snippet.

Last update: 2008.10.25.

Anime Ratings

A more-or-less complete list of anime titles I've seen, with a four-scale (very subjective) rating system.

Last update: 2008.10.23.

SVG Images

Well, it's SVG, which is a markup language, so it's text in a way :). There is an Emacs logo (100dpi PNG), the famous FailWhale (100dpi PNG) and a character from the anime series Honey and Clover called Yamada (100dpi PNG).

Last update: 2008.09.25.

Latin Memos

All the words (html) I have learned and some grammar notes (html) (in Hungarian). There is also a list of my solutions (html) to the exercises of the book "Latin for Beginners" (B. L. D'Ooge). About using the dictionary file, see the snippet page.

2008.07.04.: The answer list is now complete.

Last update: 2008.07.04.

C++ Slides

These were my "slides" for two C++ classes I gave. The first is about templates (exercises, solutions), and the second is about STL (exercises, solutions).

Last update: 2008.07.03.

OpenGL Memos

These memos are to help me remember how can I do different things with OpenGL: rotation, zoom and pan in a perspective view; NURBS surface textures; maybe more to come later.

There is also a utility to generate isophote textures.

Last update: 2008.06.30.

Essential Program list

List of the (mostly open-source) programs I frequently use.

Last update: 2008.04.14.

Fast and Local Fairing of B-Spline Curves and Surfaces

A paper I've written for the GMP 2008 conference held in Hangzhou, China. Also presented in a shorter form at the annual meeting of the Japan Society for Precision Engineering.

Last update: 2008.04.10.

Emacs Challenge

An attempt to create an enjoyable 'test yourself' quiz for Emacs users. There are only a few (basic) tasks for the moment.

There is also an answer list for my personal use.

Last update: 2008.04.05.

German Memos

All the words I have learned and some grammar notes (in Hungarian). About using the dictionary file, see the snippet page.

Last update: 2008.03.12.

When to Use Which Language?

A short note to remind myself when to use which programming language / library.

Last update: 2008.02.14.

Russian Memos

All the words I have learned and some grammar notes (in Hungarian). About using the dictionary file, see the snippet page.

Last update: 2008.01.24.

Autotools

A memo for using Autoconf/Automake.

Last update: 2007.12.21.

Music Scores

I sometimes jot down the melodies in my head - movie themes and songs, mainly. These scores were created with Lilypond; I've uploaded the source files I still have, too.

Composer Title Image Source Sound
Liu Song-bai Chun Xiao png ly
Naozumi Yamamoto Fighting Elegy Theme png ly midi
Qi Yu Ganlanshu png ly
John Williams Harry Potter Theme png ly
? JR Signal at Takada no Baba png ly
Loituma The famous Leekspin Song png ly midi
Li Chun-bo Loulan Xinniang png ly
? Misaki no toudai png ly midi
? Fragment of a repeating Naruto theme png ly midi
Tchaikovsky A few measures from (maybe) the
overture of Romeo and Juliet
png ly
? Rudolph the Red-Nosed Reindeer png ly
Li Chun-bo Xiao Fang png ly
Li Chun-bo Yi feng jiashu png ly
Deng Li-jun Yueliang daibiao wo de xin png ly

Last update: 2007.10.19.

CLOS Slides

Some slides (in Hungarian) about CLOS and the conditions system in Common Lisp, written for a class at university. Largely based on Peter Seibel's talk at Google TechTalks, also his wonderful book "Practical Common Lisp" and some other sources.

Available in OpenOffice and PDF file formats. There is also an archive of the examples I have shown during the presentation.

Last update: 2007.09.28.

Local Fairing of Freeform Curves and Surfaces

A paper I've written for the Third Hungarian Conference on Computer Graphics and Geometry, 2005.

Last update: 2007.04.13.

Master's Thesis

My master's thesis at the Eötvös Loránd University (also in PDF).

Last update: 2007.04.13.

Movie list

Some movies I like.

Last update: 2007.04.13.

Translations

Timed Hungarian translation of the Rurouni Kenshin OVA in SubStation Alpha format.

Last update: 2007.04.13.

Classical Japanese Conjugation

Classical Japanese conjugation tables in Hungarian.

Last update: 2007.04.13.

Emacs Beginner's Guide

Emacs basics in English and in Hungarian.

Last update: 2007.04.13.

Interactive Fiction Walkthroughs

Walkthroughs for Dunnet and Hunter, in Darkness.

See more information at Baf's Guide.

Last update: 2007.04.13.

Copyright (C) 2007-2024 Peter Salvi