#lang scribble/base
@(require racket scribble/core scribble/base scribble/html-properties)
@(require "defs_for-syntax.rkt" (for-syntax (planet amkhlv/bystroTeX/slides_for-syntax)))
@(require "defs.rkt" (planet amkhlv/bystroTeX/common) (planet amkhlv/bystroTeX/slides))
@(require (only-in db/base disconnect))
@; ---------------------------------------------------------------------------------------------------
@; User definitions:
@(define bystro-conf
(bystro (bystro-connect-to-server #f "127.0.0.1" 9749 "svg") ;(find-executable-path "amkhlv-java-formula.sh")
"formulas.sqlite" ; name for the database
"formulas" ; directory where to store the image files of formulas
25 ; formula size
(list 255 255 255) ; formula background color
(list 0 0 0) ; formula foreground color
2 ; automatic alignment adjustment
0 ; manual alignment adjustment
))
@(set-bystro-extension! bystro-conf "svg")
@; This controls the single page mode:
@(define singlepage-mode #f)
@(bystro-def-formula "formula-enormula-humongula!")
@; AND HOPEFULLY SOME CONTENT:
@title{BystroTeX}
Mathematical slides
using the @hyperlink["http://docs.racket-lang.org/scribble/"]{@tt{scribble}} markup system
Andrei Mikhailov, IFT UNESP
@bystro-toc[]
@slide["Inserting mathematical formulas into html slides" #:tag "MathFormulasInSlides" #:showtitle #t]{
We can insert @f{W(\phi)} as an inline formula, or a display formula:
@equation[#:label "Lagrangian" ]{
{\cal L} = \left(\partial_{\mu}\phi,\partial^{\mu}\phi\right) -
\left|\left| {\partial W(\phi)\over \partial\phi} \right|\right|^2
}
Or, formula in the box:
@longtbl[#:styless @'(((center) (right)))
@list[@list[@nested[@redbox["padding:36px;8px;0px;8px;"]{
@f{{\partial\phi\over\partial\sigma} = - {\partial W\over \partial \phi}}
}] @nested{@label{SolitonEquation}}]]]
If we need, we can also insert @f-4{x^2} shifted down,
or insert a shifted up and rescaled: @f+3+8{y^2}. @smaller{
@fsize+[-5]
We can also temporarily change the default size of the formulas. For example, this paragraph is
typeset using small font. The formula @f{yx^2} comes out smaller because we changed the default size.
After we restore the default size
@fsize=[]
@f{zx^2} is of the normal size. Some people like colored formulas:
@bystro-bg[255 200 200] @bystro-fg[0 0 250]
@f{\; l^2 = a^2 + b^2}
@bystro-bg[255 255 255] @bystro-fg[0 0 0]
}
See the @seclink["Syntax"]{syntax part} for more examples.
}
@after-pause{
@tabular[@list[@list[@para{
Besides the math-specific task of inserting formulas, many things can be done using
the @hyperlink["http://docs.racket-lang.org/scribble/"]{well documented} @tt{scribble} environment.
@linebreak[]
For example, one can include pictures, as illustrated. Flying kite could be an allegory for slide presentations.}
@smaller-2{@(image (string->path "snapshots/kite.png") #:scale 0.5)
@hyperlink["http://openclipart.org/detail/67597/child-with-a-kite-by-laobc"]{openclipart.org}}]]]
}
@remove-slide[]
@after-pause{
@clr["red"]{ Also supported pause and removal of slides.}
}
@slide["Jumping to references" #:tag "JumpingReferences" #:showtitle #t]{
Remember the formula (@ref{Lagrangian})? Clicking on
(@ref{Lagrangian}) brings you to that formula.
It is also possible to jump to a particular slide, for example
@seclink["Installation"]{jump to ``Installation''}.
Sometimes you might want to press the ``up'' link, which will bring you to the title page.
The title page has the list of contents, so you can jump to particular slides from there.
}
@slide["Installation Part I" #:tag "Installation" #:showtitle #t]{
BystroTeX consists of the frontend (Racket) and backend (Java). The Java part works
like a server. It is actually an HTTP server. It listens on some port on the @tt{localhost}.
We will start with @bold{setting up this server}.
First of all, you need to have installed @bold{Java 7 or 8} (because Java 6 will not work), including the JDK.
OpenJDK is OK. To verify that you have Java installed, type the commands:
@verb{
java -version
javac -version
}
They should say something like ``java version 1.7....'' and ``javac 1.7....''.
To install the server, you need the command called @tt{git}.
Execute the following commands:
@smaller{@tt{git clone https://github.com/amkhlv/latex2svg}}
@smaller{@tt{cd latex2svg}}
@smaller{@tt{./activator stage}}
This will take some time, as various libraries will have to be downloaded (and saved in @tt{~/.ivy2}).
After that, execute this command:
@smaller{@tt{target/universal/stage/bin/latex2svg -Dhttp.port=9749 -Dhttp.address=127.0.0.1}}
Now the server is running. Notice that we specified the option @smaller{@tt{-Dhttp.address=127.0.0.1}}. Therefore the server
is only listening on a local interface (the ``loopback''); @bold{it is not possible to connect to it from the outside}.
}
@slide["Installation Part II" #:tag "Installation2" #:showtitle #t]{
Now comes the frontend.
You should start with installing @hyperlink["http://racket-lang.org/"]{@tt{Racket}} on your computer.
For example, on @tt{Debian} you should issue this command @bold{@clr["red"]{as root:}}
@verb{
aptitude install racket
}
This command will install the @tt{Racket} environment on your computer. Now we are ready to
install @tt{bystroTeX}.
There are two methods of installation:
@table-of-contents[]
@smaller{Comments @bold{for Windows users}:}
@itemlist[
@item{@smaller{Install @seclink["FromGitHub"]{from GitHub}}}
@item{@smaller{You will have to manually install the @tt{dll} for the @tt{sqlite3}, please consult the Google}}
]
@section{Installation from Planet}
Execute this command @bold{@clr["red"]{as a normal user}} (i.e. @bold{@clr["red"]{not}} root):
@verb{
racket -e '(require (planet amkhlv/bystroTeX/slides_setup))'
}
This command will take some time, because it has to download and compile things.
It will talk back to you, asking some questions and giving further instructions.
During the installation you will be asked to choose a folder
where a sample slide presentation will be stored.
After the installation, @spn[attn]{go to that sample folder}.
@section[#:tag "FromGitHub"]{Installation from GitHub}
The second method of @tt{bystroTeX} installation is to install directly from its @tt{git} repository.
I usually set up a ``development link'', this way I can do changes in the repository and they are
immediately in effect. This is done as follows: @bold{@clr["red"]{as a normal user}} (i.e. @bold{@clr["red"]{not}} root),
exectute:
@smaller{@tt{git clone https://github.com/amkhlv/amkhlv}}
@smaller{@tt{cd amkhlv}}
@smaller{@tt{raco planet link amkhlv bystroTeX.plt 7 1 bystroTeX/}}
With this method of installation, the sample folder ends up in in @tt{bystroTeX/example-slides}
Now @spn[attn]{go to that sample folder}:
@smaller{@tt{cd bystroTeX/example-slides}}
}
@slide["Sample presentation" #:tag "SamplePresentation" #:showtitle #t]{
You should find that the sample folder contains (at least) the following files:
@tbl[#:orient 'hor @list[@list[@larger["Filename"] @larger["purpose"]]
@list[@tt{slides-manual.scrbl} "main source file"]
@list[@tt{defs.rkt} "additional definitions"]
@list[@tt{defs_for-syntax.rkt} "syntax preferences"]
@list[@tt{slide.css} "style of the regular slide"]
@list[@tt{slide-title.css} "style of the title slide"]
@list[@tt{misc.css} "various elements of style"]
]]
The command to actually ``build'' the slideshow is:
@verb|{
scribble --htmls slides-manual.scrbl
}|
This command may take some time when you run it for the first time. There are two possible
outcomes:
@itemlist[#:style 'ordered
@item{If something goes wrong, see the @seclink["Troubleshooting"]{Troubleshooting section}.}
@item{If the command succeeds, it will generate the @tt{html} files in the new folder called @tt{slides-manual}.}
]
Then you can view it in @tt{Firefox}:
@verb|{
firefox slides-manual/index.html
}|
}
@slide["Adjusting fontsizes, width and other style" #:tag "AdjustCSS" #:showtitle #t]{
Most of things are done in 2 @tt{css} files, @tt{slide.css} and @tt{slide-title.css}.
The first file is for the regular slide, and the second for the titlepage.
@smaller-2{@bold{@clr["red"]{Note}}:
I am talking about the files in the root of the sample folder. When you
@seclink["SamplePresentation"]{compile}, they get copied into the subfolder
@tt{slides-manual/index.html}. Everything in that subfolder (in particular @tt{css} files)
is auto-generated. Therefore, you should not edit anything there!
}
How to figure out which element of the slide corresponds to which section of the @tt{css} file?
Firefox has the ``style inspector'' tool which reveals names.
It is activated by pressing @tt{Ctrl-Shift-I}.
If you press on the ``style'' tab, it will even show you from which line of the @tt{css} file
came this or that element on the page! @smaller-2{(To turn it off press @tt{Ctrl-Shift-I} again.)}
Notice that the width is controlled by the @tt{width} parameter of @tt{.maincolumn}.
}
@slide["Will it fit on the projector screen?" #:tag "FitProjector" #:showtitle #t]{
This is a very important question. Before giving a talk, try to figure out the projector resolution.
(I think most of them are 1024x768.) I once got the projector replaced just before my talk,
so I found myself trying to @seclink["AdjustCSS"]{edit the .css files} right in front of the audience.
@smaller-2{(Nice exercise!)}
Linux has a command called @tt{xte}, which can position the mouse cursor at a given point
on the screen. For example:
@verb|{
xte 'mousemove 1024 768'
}|
Maybe this can be used to check if your slide will fit.
The easiest way to adjust the width of the slide is by using the @tt{width}
parameter of @tt{.maincolumn}.
@smaller{
Alternatively, you can change the font sizes. If you do decide to change the font sizes, you
might also need to adjust the formula size in the headers of the @tt{.scrbl} file, and
perhaps in the @tt|--{@fsize[]}--| function.
}
}
@slide["Basic syntax" #:tag "Syntax" #:showtitle #t]{
You might want to read @hyperlink["http://docs.racket-lang.org/scribble/reader.html"]{basic Scribble documentation},
but it should not be necessary. Just look at the source file and proceed by analogy.
Also have a look at the ``docs'' link @hyperlink["http://planet.racket-lang.org/display.ss?package=bystroTeX.plt&owner=amkhlv"]{on PLaneT}.
More examples can be found @hyperlink["https://github.com/amkhlv/dgcm"]{here}.
@table-of-contents[]
@section{Simple formulas}
To insert formula @f{x^2/y^2}, type:
@verb|{@f{x^2/y^2}}|
Curly brackets inside are usually not a problem: for @f{y_{ij}} just type
@verb|{@f{y_{ij}}}|
it works. If however something goes wrong, you might want to use better protection:
@verb|---{@f|{y_{ij}}| or even @f|-{y_{ij}}-| }---|
@div[comment]{Whether you need to use @tt|{@f|-{...}-|}|, or @tt|{@f{...}}| is enough, depends on
the structure of parentheses inside your formula. @bold{If parentheses are well-balanced} then
@tt|{@f{...}}| is enough. If not, then better protection is needed. For example, if the formula
is: @f-4|{v = \left\{\begin{array}{l} u \mbox{ if } u \geq 0 \cr -u \mbox{ if } u < 0\end{array}\right.}|,
then you absolutely need to use @tt|{@f|-{...}-|}|, since the @f|{\{}| is unbalanced}
There is also the display-style @tt|--{@equation{...}}--| which allows formula labeling using
@tt|--{@equation[#:tag "FormulaName"]{...}}--|.
It is also possible to manually align the formulas, for example
@tt|--{@f+4{x^2}}--| produces @f+4{x^2} and @tt|--{@f-7{x^2}}--| gives @f-7{x^2}.
There is also zoomed @tt|--{@f+0+7{x^2}}--| which gives @f+0+7{x^2} and zoom
with align @tt|--{@f-5+7{x^2}}--| which gives @f-5+7{x^2}.
The command @tt|--{@fsize[20]}--| changes the formula size to 20pt, the command @tt|--{@fsize[]}--|
or equivalently @tt|--{@fsize=[]}--|
returns back to the previous size (but you can not nest them, there is not stack of sizes).
Actually I recommend to use instead the command @tt|--{@fsize+[5]}--| which changes the
size relatively to the base size. This will scale better if you will have to suddenly
@seclink["FitProjector"]{change the resolution} 3 minutes before your talk.
To decrease the size, use @tt|--{@fsize+[@-[5]]}--| or equivalently @tt|--{@(fsize+ (- 5))}--|.
Both @tt|{@fsize[]}| and @tt|{@fsize+[]}| have an optional second argument, which modifies
the vertical base alignment.
@section{Multiline formulas}
Example:
@verb|{
@align[r.l
@list[
@f{{2\over 1 - x^2} = } @f{1+x+x^2 + \ldots +}
]@list[
"" @f{1-x+x^2- \ldots}
]
]
}|
produces:
@align[r.l
@list[
@f{{2\over 1 - x^2} = } @f{1+x+x^2 + \ldots +}
]@list[
"" @f{1-x+x^2- \ldots}
]
]
The only problem is, there is a small alignment defect. To fix it, do this:
@verb|{
@align[r.l
@list[
@f{{2\over 1 - x^2} = } @v+[3 @f{1+x+x^2 + \ldots +}]
]@list[
"" @f{1-x+x^2- \ldots}
]
]
}|
@align[r.l
@list[
@f{{2\over 1 - x^2} = } @v+[3 @f{1+x+x^2 + \ldots +}]
]@list[
"" @f{1-x+x^2- \ldots}
]
]
Notice that in the first line stands the symbol "r.l" which defines the alignment (right, then left). The "v+" is a padding,
it serves for vertical adjustment, see the
@hyperlink["http://planet.racket-lang.org/package-source/amkhlv/bystroTeX.plt/6/3/planet-docs/manual/index.html"]{manual page}.
The numbered version of the same formula will be
@verb|{
@align[r.l.n
@list[
@f{{2\over 1 - x^2} = } @v+[3 @f{1+x+x^2 + \ldots +}] ""
]@list[
"" @f{1-x+x^2- \ldots} @label{SumOfGeometricProgressions}
]
]
}|
@align[r.l.n
@list[
@f{{2\over 1 - x^2} = } @v+[3 @f{1+x+x^2 + \ldots +}] ""
]@list[
"" @f{1-x+x^2- \ldots} @label{SumOfGeometricProgressions}
]
]
Notice that the alignment symbol is now r.l.n, we added letter n for the number. The function @tt|{@label[]}| is defined in the slides’ header.
@section{Fun with Unicode}
To get @f{A\otimes B} just type: @tt|{@f{A⊗B}}|. In other words, we can use the Unicode symbol ⊗ instead of @tt{\otimes} in formulas.
@section{Color in formulas}
@verb|{
@bystro-bg[255 200 200] @bystro-fg[0 0 250]
@f{\; l^2 = a^2 + b^2}
@bystro-bg[255 255 255] @bystro-fg[0 0 0]
}|
gives @bystro-bg[255 200 200] @bystro-fg[0 0 250]
@f{\; l^2 = a^2 + b^2}
@bystro-bg[255 255 255] @bystro-fg[0 0 0]
@section{Some technical details}
We use @hyperlink["http://forge.scilab.org/index.php/p/jlatexmath/"]{@tt{JLaTeXMath}} to produce @tt{svg} (or @tt{png}) files.
We had some problems with large size integral signs: @f{\int {f\over g} dt} and large size
brackets: @f{\left( {x\over y} \right)}. As you can see, they come out a bit weird.
It seems that this is caused by a general bug in @tt{OpenJDK} (which is the default implementation
of Java on Debian). The situation is discussed
@hyperlink["http://forge.scilab.org/index.php/p/jlatexmath/issues/676/"]{here}.
If this becomes a problem, use
@hyperlink["http://www.oracle.com/technetwork/java/javase/downloads/index.html"]{Sun JDK}
instead of @tt{OpenJDK}. (The page you are reading now was prepared using @tt{OpenJDK}.)
@div[redbox]{
This slide is very tall and will probably go below the bottom of the display area, so you
need to scroll down to read it.
This is intentional. Sometimes you have to show a long list of formulas.
Scrolling is easier on the audience than jumping from page to page.
}
}
@slide[@elem{Putting @f{\epsilon} and @f{\delta} in the slide title} #:tag "FormulasInSlideTitle" #:showtitle #t]{
@verb|{
@slide[@elem{Putting @f{\epsilon} and @f{\delta} in the slide title} #:tag "FormulasInSlideTitle" #:showtitle #t]{
...
}
}|
}
@slide["Writing html in scribble" #:tag "InsertingHTML" #:showtitle #t]{
What if we want to insert, for example, a remote animated gif
from @hyperlink["http://www.123gifs.eu/free-gifs"]{123gifs.eu} ?
As far as I understand, there is no way to directly insert a raw @tt{html} code in scribble.
Instead, we have to rewrite our @tt{html}
the @hyperlink["http://docs.racket-lang.org/scribble/index.html"]{scribble way}. For example, @bold{this HTML}:
@(element
(make-style #f (list
(alt-tag "img")
(attributes
(list
(cons 'style "border:0;")
(cons 'src "http://www.123gifs.eu/free-gifs/flags/flagge-0544.gif")
(cons 'alt "flagge-0544.gif from 123gifs.eu")
))))
"Flag of Brazil"
)
@verb[#:style @(make-style "comment" '())]|{
Flag of Brazil
}|
@bold{will become:}
@verb[#:style @(make-style "comment" '())]|--{
@(element
(make-style #f (list
(alt-tag "img")
(attributes
(list
(cons 'style "border:0;")
(cons 'src "http://www.123gifs.eu/free-gifs/flags/flagge-0544.gif")
(cons 'alt "flagge-0544.gif from 123gifs.eu")
))))
"Flag of Brazil"
)
}--|
}
@slide["Notes for emacs users" #:tag "Emacs" #:showtitle #t]{
If you use @tt{emacs}, I would highly recommend installing the @tt{emacs} scripts
from @hyperlink["http://www.neilvandyke.org"]{www.neilvandyke.org}. Not as powerful as
@hyperlink["http://www.gnu.org/s/auctex/"]{AUCTeX}, but still very cool!
Some more staff in @tt{.emacs}, if you wish:
@verb[#:style @(make-style "comment" '())]|--{
(add-outline 'scribble-mode-hook)
(add-hook 'scribble-mode-hook '(lambda () (setq outline-regexp "@section\\|@subsection\\|@subsubsection\\|@slide")))
(defface scribble-slide-face
'((((class color) (background dark)) (:inherit variable-pitch :family "Terminus" :foreground "khaki2" :weight bold :height 1.2)))
"Basic face for highlighting the scribble slide title.")
(add-hook 'scribble-mode-hook '(lambda () (font-lock-add-keywords 'scribble-mode
'(("@slide\\[\"\\(.*?\\)\".*\\]" 1 'scribble-slide-face prepend)
("@slide\\[@elem{\\(.*?\\)}.*\\]" 1 'scribble-slide-face prepend)
("@\\(after-pause\\)" 1 'font-lock-warning-face prepend)
("@\\(slide\\)" 1 'font-lock-warning-face prepend)))))
}--|
--- for more syntax highlighting
}
@slide["Sections in slide" #:tag "Sections" #:showtitle #t]{
@table-of-contents[]
@section{Introduction}
A slide can contain sections
@section{Disadvantages}
Obviously, this is a bad idea when giving a talk:
@subsection{First disadvantage}
Audience will get confused.
@subsection{Second disadvantage}
Audience will start reading section titles instead of reading formulas.
@section{Advantages}
But it could be good for something else.
}
@slide["Single page and printing" #:tag "SinglePage" #:showtitle #t]{
It is also possible to have everything on one single long @tt{html} page.
For that, two things have to be done:
@itemlist[#:style 'ordered
@item{Change @tt|{@(define singlepage-mode #f)}| to @tt|{@(define singlepage-mode #t)}| in the
headers of your @tt{.scrbl} file}
@item{Different method of compilation.
Instead of compiling as we explained @seclink["SamplePresentation"]{here}, do this:
@itemlist[#:style 'ordered
@item{Create new directory: @verb{mkdir singlepage}}
@item{Now compile: @verb|{scribble --dest singlepage slides-manual.scrbl}|
}]}]
This might be useful, for example, for @red{printing}. However, it is also easy
to print multiple pages, using the program called @hyperlink["http://wkhtmltopdf.org/"]{wkhtmltopdf}.
The only problem is to keep track of the ordering of pages. Notice that the @tt{index.html} has the
list of all your multiple pages, and this script will extract them and print the filenames sorted:
@verb[#:style @(make-style "comment" '())]|--{
#!/usr/bin/env racket
#lang racket
(require xml xml/path racket/file)
(define x
(call-with-input-file "index.html"
(lambda (inport) (xml->xexpr (document-element (read-xml inport))))))
(for ([ttl (se-path*/list '(a) x)]
#:when (and (string? ttl) (equal? (se-path* '(a #:class) x) "toptoclink")))
(for ([fp (find-files
(lambda (f) (equal? (string-append ttl ".html") (path->string f))))])
(write-string (path->string fp))
(newline))
(for ([fp (find-files
(lambda (f) (regexp-match
(regexp (string-append ttl "_[0-9]+" ".html"))
(path->string f))))])
(display (path->string fp))
(newline))))
}--|
}
@slide["Automatic LaTeX → BystroTeX conversion" #:tag "LaTeX2BystroTeX" #:showtitle #t]{
I have tried to write a program which converts a LaTeX document into BystroTeX, for example
replaces every @tt{$x$} with @tt|--{@f{x}}--|. This is very difficult to do correctly,
because LaTeX is extremely difficult to parse. What I did is a very naive zeroth approximation.
The resulting script is @tt{l2b.rkt} which is in the sample directory. It accepts LaTeX on @tt{stdin}
and outputs BystroTeX to @tt{stdout}.
To compile it, execute the following command:
@verb{raco exe l2b.rkt}
This will create the executable called @tt{l2b}. Example of use:
@verb{echo 'example: $1$' | ./l2b}
The output should be:
@verb|-{example: @f{1}}-|
The problem is, every person writes LaTeX in their own way.
For example, some people write @tt|{\beq}| instead of @tt|{\begin{equation}}|.
So, if you want to use a converter like this, you would probably have to modify it to fit your
own LaTeX style.
}
@slide["Updating bystroTeX" #:tag "Updating" #:showtitle #t]{
If you already have @tt{bystroTeX} installed, but want to update to the latest
version. Go to @hyperlink["http://planet.racket-lang.org/display.ss?package=bystroTeX.plt&owner=amkhlv"]{the Planet page}.
Somewhere at the top of the page, you will find the following line:
@verb|{
To load: (require (planet amkhlv/bystroTeX:5:0/slides_setup))
}|
except for instead of @tt{bystroTeX:5:0} there will be @tt{bystroTeX:m:n} where @tt{m:n} is the latest version number.
Then execute this command:
@verb|{
racket -e '(require (planet amkhlv/bystroTeX:m:n/slides_setup))'
}|
This will repeat the installation procedure and update to the latest version.
I recommend cleaning up the directories @tt{~/bystro} and @tt{~/java} (or whatever you called them
@seclink["Installation"]{during the previous installation}) before updating. This is because I may
have some changes both in the sample slides and in the Java part.
}
@slide["Troubleshooting" #:tag "Troubleshooting" #:showtitle #t]{
You need @bold{Java 7} (because Java 6 will not work). OpenJDK should be OK.
Java errors are dumped to @tt{server-error.txt}.
@tbl[#:orient 'hor @list[
@list[
@para{Something is very wrong}
@para{Check if the @tt{singlepage-mode} parameter is set up
correctly in the headers, as explained @seclink["SinglePage"]{here}.}
]@list[
@para{Some formulas look ugly}
@para{Use Sun Java as explained @seclink["Syntax"]{here}}
]@list[
@para{First time execution of the ``@tt{scribble ...}'' command takes about half a minute, and then error message like @tt{read-xml: parse-error: expected root element ...}}
@para{Looks like a Java error, cannot find @tt{jlatexmath.jar} or something; see the contents of the log file @tt{server-error.txt}}
]@list[
@para{Execution of the command ``@tt{scribble ...}'' freezes}
@para{If your talk has many formulas, and this is the first time you are
executing the @tt{scribble} command, you may need to wait 1 min or so...
But sometimes it, really, freezes.
This may happen on slow machines. Do the following:
@linebreak[]
1. Stop @tt{scribble} (just @tt{Ctrl-C})
@linebreak[]
2. @tt{rm bystrotex.fifo}
@linebreak[]
3. @tt{rm formulas.sqlite}
@linebreak[]
4. @tt{rm formulas/*}
@linebreak[]
5. @tt{pkill -n java}
@linebreak[]
6. Start your @tt{scribble} command again
}
]
]]
}
@slide["Alternative backends" #:tag "AlternativeBackend" #:showtitle #t]{
We think that it is best to @seclink["Installation"]{use our HTTP server} as a backend.
But it is also possible, instead of connecting to a server, just call a program of
your choice. That program should satisfy the following properties:
@itemlist[#:style 'ordered
@item{It should wait on @tt{stdin} for a text string of the form:
@verb|{
\sum_{n>0} {x^n\over n}
}|
(this is @hyperlink["http://en.wikipedia.org/wiki/XML"]{XML})
}
@item{Upon the receipt of such a text string, it should do two things:
@itemlist[
@item{Write the picture of the formula in the @tt{png} format to @tt{formulas/3.png}}
@item{Print on @tt{stdout} the text like this:
@verb|{
7
}|
which reports the depth (@italic{i.e.} vertical offset) of the formula}
]}
]
The name of such a program (here it is @tt{amkhlv-java-formula.sh}) should be
specified (among other things) at the top of the slides header in these lines:
@verb|{
@(define bystro-conf
(bystro (find-executable-path "amkhlv-java-formula.sh")
"formulas.sqlite" ; name for the database
"formulas" ; directory where to store .png files of formulas
25 ; formula size
2 ; automatic alignment adjustment
0 ; manual alignment adjustment
))
}|
}
@slide["Why not Beamer?" #:tag "Beamer" #:showtitle #t]{
There is an excellent tool called @hyperlink["http://en.wikipedia.org/wiki/Beamer_(LaTeX)"]{Beamer},
which is based on @tt{LaTeX} and can be used with @hyperlink["http://www.gnu.org/s/auctex/"]{AUCTeX}.
The problem is, I don't like @tt{TeX} and @tt{LaTeX}. This is, of course, a matter of personal preference.
Also, Scribble produces @tt{.html} files. I find @tt{.html} format more convenient for giving presentations
than the @tt{Beamer}'s format @tt{.pdf}.
@elem[#:style @bystro-elemstyle["text-decoration:blink;"]]{Most importantly: Beamer won't give you blinking text.}
@div[comment]{It turns out, that Firefox @hyperlink["https://bugzilla.mozilla.org/show_bug.cgi?id=857820"]{disabled blink-effect},
what a pity!}
}
@slide["From TeX to HTML?" #:tag "FromTeXtoHTML" #:showtitle #t]{
I think that we should @bold{switch from TeX to HTML}:
@itemlist[
@item{TeX is optimized for the quality of typesetting. This is not very important for us.}
@item{HTML is all about @spn[attn]{creating links}. This is exactly what we need.
After all, scientific publishing is for @spn[attn]{linking} ideas.}
@item{Practically, TeX is very hard to learn, and hard to use properly.
With the right markup tools (perhaps this project?) HTML should be easier.}
@item{Learning the syntax of LISP (@hyperlink["http://racket-lang.org/"]{Racket}) is pleasure.
The syntax of TeX/LaTeX is pain.}
]
}
@; ---------------------------------------------------------------------------------------------------
@disconnect[formula-database]
@(bystro-close-connection bystro-conf)