|  |  | 8.1 Presentation stylesheets

## 8.1 Presentation stylesheets

A presentation must use a dedicated stylesheet. Presentations must use much larger fonts than what is normal for a figure. Don't try to make use of the "LARGE" and "huge" textsizes, but use a stylesheet that properly defines "normal" to be a large textsize.

Ipe comes with a style sheet presentation.isy that can be used for presentations. To create a new presentation, you can simply say:

      ipe -sheet presentation

Note that presentation.isy is meant to be used instead of basic.isy (not in addition to it).

This presentation stylesheet enlarges all standard sizes by a factor 2.8. Note the use of the `<textstretch>` element to magnify text:

    <textstretch name="normal" value="2.8"/>
    <textstretch name="large" value="2.8"/>

The text size you choose from the Ipe user interface ("large", for instance) is in fact used for two symbolic attributes, namely `textsize` (where large maps to `\large`) and `textstretch` (where it maps to no stretch in the standard style sheet). By setting the text stretch, you can magnify fonts.

In addition, the `<layout>` element in this stylesheet redefines the paper size to be of the correct proportions for a projector, and defines a smaller area of the paper as the frame. The frame is the area that should be used for the contents. The Insert text box function, for instance, creates text objects that fill exactly the width of the frame.

The `<titlestyle>` element defines the style of the page title outside the frame. You can set the title for each page using the Edit title & sections function in the Page menu.

The LaTeX-preamble defined in the `<preamble>` element redefines the standard font shape to `cmss` (Computer Modern Sans Serif). Many people find sans-serif fonts easier to read on a screen. In addition, it redefines the list environments to use less spacing, and the text styles to not justify paragraphs (the `<textstyle>` elements).

If you wish to use the page transition effects of Acrobat Reader, you can define the effects in the stylesheet (using `<effect>` elements), and set them using Edit effect in the View menu.

If you want to number the pages of the presentation, you'll need to use the `<pagenumberstyle>` element. It defines color, size, position, and alignment of the page number, and provides a template for the page number text. The template can use the following Latex counters:

- `ipePage` for the current page number,
- `ipeView` for the current view number,
- `ipePages` for the total number of pages,
- `ipeViews` for the number of views of the current page,

and the special macro `\ipeNumber{x}{y}` that evaluates to `x` when the page has only one view, and to `y` if there is more than one view.

If the template is empty, this has the same effect as the following definition (this is also the default definition):

    \ipeNumber{\arabic{ipePage}}{\arabic{ipePage} - \arabic{ipeView}}

The following example definition indicates the views of a single page with letters A, B, C, …:

    <pagenumberstyle pos="300 100" size="Huge" color="navy"
      halign="center">\ipeNumber{\arabic{ipePage}}{\arabic{ipePage}
    \Alph{ipeView}}</pagenumberstyle>

The following definition uses roman numerals for the pages and does not indicate different views at all:

    <pagenumberstyle pos="580 20" size="Huge" color="purple"
      halign="right">\roman{ipePage}</pagenumberstyle>

And this shows both the current page and the total number of pages:

    <pagenumberstyle pos="20 820" size="Huge" color="0.5 0 0"
      valign="top">\arabic{ipePage}/\arabic{ipePages}</pagenumberstyle>