EpsilonWriter Creator - Mathematical greeting cards  

5th January 2017  



Modifying an existent open source card


We will modify the card " 30 - Papillon exemple no 30". This require to create a new file on the epsilo-publi website.


To do so, you must use a computer with Java installed.

You also have to create an account (free) on epsilon-publi(except if you already have one), using the following link:  


then choose the "Inscription" item from the "Authors" menu.


To start working, launch EpsilonWriter Creator Java Web Start, from the page:


in "Quick access..." part.


Then find the source code of "30 - Papillon exemple no 30", following the link http://www.epsilon-publi.net/j/jnicaud/vx/ , locate the resource and click on "Description". Follow the guidelines at the bottom of the page to transfer the source code to EpsilonWriter Creator.

When you paste, answer "yes" to the question "Open in authoring mode".


Saving on epsilon-publi


Now you will save your document on the website. Then you will modify it and save it again.

Click on the "Web" menu. If "Connection to epsilon-publi" appears, do the connection the go back to the document ("left arrow" button or "Close" menu).

If it is not displayed, you are already connected.

Now click on  "Web | Web save as ( read only mode). A small window opens with "Title" and "Author" fields, modify these values as you wish then click on "ok".

You are at that time in the web files explorer, ready to save. If the button imageReference _Manuel-Cartes-en.html/image1.png appears,  just click on it. If it does not appear, you first have to click on the "open" icon imageReference _Manuel-Cartes-en.html/image2.png to open a workspace.

Now go back to the document ("left arrow" button or "Close" menu), change the text of the card and then save the document using the imageReference _Manuel-Cartes-en.html/image3.png button  from the document tab imageReference _Manuel-Cartes-en.html/image4.png .

To see the card running, go to the explorer with "Web | Open Web..."  

The imageReference _Manuel-Cartes-en.html/image5.png button next to the name of your resource sends you to the description in the web browser. There, there is an "Open" link that  launches the resource.

The link imageReference _Manuel-Cartes-en.html/image6.png next to the name of your resource set the URL of the resource in the clipboard. You can then paste it in the address bar of your web browser to run the resource or in a message to send it to a contact.


Some explanations


This document includes an animation because there is an equation of an animation ( a "for" with correct formulas on the left and on the right)  and the two animation buttons below:  

imageReference _Manuel-Cartes-en.html/image7.png

The accolade that is the most on the left is used to put one or several formulas to draw the curves.

Here, there is a single one which is x=a cos(t/2) and y=-0.5+a sin(t) and 0≤t≤4π defining a parametric curve. This more internal accolade is put in parenthesis to ease changes.


The parametric equation used is x= cos(t/2) and y= sin(t)

In the document wording, a zoom factor a has been added and a -0.5 offset on the y axis. The interval considered for the drawing has also been indicated with 0≤t≤4π

On the right of "for", we found the formulas that define the parameters. First the main parameter which is an integer (letter of your choice) that will take all the values between the two given bounds. A display is rendered  for each value taken by this parameter, then , if needed, definitions of some parameters with "let".

In the example, the a zoom equals n/6  so the zoom will increase  (the butterfly is growing) when n increases.  


As you saved on epsilon-publi in a read only mode the animation will start automatically when you open the resource (otherwise it would open as a document, as in EpsilonWriter Creator).


Modifying the animation


Modify the formulas to get this :


(x=d+a cos(t/2) and y=-0.5+a sin(t) and 0≤t≤4π) for 0≤n≤10 and let a=(6+n)/12 and let d=n-5                        


n varies from 0 to 10 now, the a zoom increases slower and an offset d on the x has been added. Thus, The butterfly will move by translation along the x .


To test the animation, click on theimageReference _Manuel-Cartes-en.html/image13.png button and answer "yes" to  "Draw in the web browser". The animation is made in the browser without displaying texts.


The  butterfly goes up

add d/2 to y writing y=d/2-0.5+a sin(t)

Before starting the animation, close the other tabs to avoid the navigator being slowed down.  


Adding a bar in the butterfly


Add the function y=d/2-0.5 in the formulas to be traced . That has to be made in the first accolade, below the second one:

(x=d+a cos(t/2) and y=d/2-0.5+a sin(t) and 0≤t≤4π) and y=d/2-0.5

Before starting the animation, close the other tabs to prevent the web browser slowing down.


To make a bar that do not overflow the butterfly , add conditions with the with operator:  

y=d/2-0.5 with d-a≤x≤d+a


Using a segment

You can change the straight line with constraints y=d/2-0.5 with d-a≤x≤d+a

by a segment segment(d-a;d/2-0.5;d+a;d/2-0.5)

use the "segment" button from the "Draw" panel to do so.



Choosing colors of the curves


Select the button panel "Draw" :

imageReference _Manuel-Cartes-en.html/image20.png

Put the cursor in the formula of the butterfly and click on the red button. The formula turns to red.

Put the cursor in the formula of the straight line and click on the green button. The formula turns to green.  

Start the animation, it produce the following butterfly :

imageReference _Manuel-Cartes-en.html/image21.png


Save your work and run it as described at the beginning of this manual to see both the text and  the animation.



The black button remove the color. When you want to change a formula, it is better to remove the color, change the formula then put the color again. It avoids addition of useless parenthesis and enables to see if there are unbalanced parentheses.



Several texts that follow each other


To get a display with several texts that follow each other every 20 seconds, you have to put the texts in a table.

In EpsilonWriter Creator,  as previously, retrieve the source code of the resource "31 - Papillon exemple no 31", following the link http://www.epsilon-publi.net/j/jnicaud/vx/ to get an example.


The tableau has 1 column and 2 rows. The texts included in the two rows are displayed alternatively.

You can add or delete rows  with the "Table" menu.  


Bilingual english and french


To get a bilingua french and english card , you have to put the texts in two columns of a table.

Retrieve in EpsilonWriter Creator, as previously, the source code of the resource "32 - Papillon exemple no 32", to see an example.  


The table includes 2 columns, the first one start with  fr for the french texts,  the other one with en for the english texts.

Only french and english are available here.

It is possible to write texts in other languages but the operating language here have to be fr or en.




The cards from the gallery are open sources. You can get the source code at  http://www.epsilon-publi.net/j/jnicaud/vx/  


For a better understanding of EpsilonWriter, see the user manual