RISC OS Present

RISC OS Present is a slide presentation tool initially intended for full screen use at a presentation for ROUGOL. It provides is able to render slides from a deck, described in Markdown.

Markdown Format

The markdown format follows the style of markdown used by Remark. There are limitations to what can be handled by the parser and renderer, and there are some extensions.

Slide delimiting and styles

Slides are separated by the horizontal rule marker (---). The slide separator may be immediately followed by properties which should be applied to this (and subsequent) slides. The properties take the form of colon-separated key-value pairs, which give the property name and its value. Properties may be deleted by prefixing their name with a single - character.

The following properties are defined:

• name: Declares a name for this slide (used by the templates)
• template: Declares the slide name which should be used as the basis for this slide - must be the first property of the slide. The templates only take property information from the templated slide.
• background-colour/foreground-colour: Changes the slide background and text foreground colour. It is not currently possible to change the colour of text inline. Colours may be named CSS colours, #RRGGBB, #RGB, rgb(r,g,b) or rgb(r%,g%,b%) values (as supported by the WebColours module).
• *.font/*.size/*.height: Defines font characteristics for the main styles used within the slides. Each font name may be suffixed by .bold and .italic (in that order) to configure specific font styles. The size and height are only configurable on the base font at the current time. The following font names may be defined:
  • body
  • h1, h2, h3
  • code
  • quote
  • marginal
• h#.padding.top/h#.padding.bottom/h#.padding.inset: Defines the padding at the top and the bottom of the headings, and the inset for the text in the heading.
• vertical-align: Alignment of the slide content, which may take the value top, middle, or bottom.
• padding/padding-horizontal/padding-vertical: Defines the size of the slide padding.
• list.padding.top/list.padding.bottom: Defines the space around lists.
• item.padding.top/item.padding.bottom: Defines the space around each list item.
• item.padding.inset: Defines the inset horizontally of each list item's text (or bullet).
• item.padding.offset: Defines the offset horizontally from the inset point to the text of the item's body.
• pre.padding.inset: Defines the inset horizontally that the preformatted text blocks use
• pre.padding.inside: Defines the space between the border and the content of the preformatted text.
• pre.border.width: Defines the width of the border around preformatted text.
• pre.border.type: Defines the type of border placed around the preformatted region, which can take the following values:
  • none: No border.
  • solid: Single colour, solid border.
  • double: Two borders, each with width 1/3 of the set width.
  • inset: A 3D effect, sunk into the region (light top left).
  • outset: A 3D effect, raised from the region (light top left).
  • ridge: A 3D effect, a ridge around the region (light top left).
  • groove: A 3D effect, a sunken groove around the region (light top left).
• pre.border.background-colour: Defines the colour of the background, or none to not use any
• pre.border.colour: Defines the colour of the border, or none to not use any
• pre.border.fore-colour: Defines the colour of the 3D effect fore colour, or none to not use any
• pre.border.opposite-colour: Defines the colour of the 3D effect opposite colour, or none to not use any
• quote.padding.top/quote.padding.bottom: Defines the space around a block quote
• quote.padding.inset: Defines the inset horizontally of the block quote to the quote bar.
• quote.padding.offset: Defines the offset horizontally from the inset point to the text of the block quote's body.
• quote.bar.width: Defines the width of the quote bar.
• quote.bar.colour: Defines the colour of the quote bar.
• logo.POSITION: Defines an image to place in a given position (see below)
• logo.POSITION.inset: Defines the gap around the outside of the image to leave.
• logo.POSITION.width/logo.POSITION.height: Defines the width/height of the image (which will be limited by the size of the slide)
• slidenumber.position: defines a position for the slide number label on each slide, where the position value can be any of the position specifications (or none to remove the slide number).
• slidenumber.padding: defines the spacing from the edge of the screen for the slide number.
• slidenumber.format: defines how the slide number is printed as a string. $s is replaced by the slide number, and $m by the maximum slider number.

Position specifications

Positions are used for a few of the properties. The following positions are defined:

• top-left
• top
• top-right
• left
• centre
• right
• bottom-left
• bottom
• bottom-right

Size specifications

Sizes can be in pixels (which corresponds to 2 OS units, even in EX0/EY0 modes) or with size specifications:

• #pt: In points (effectively 1 pixels at present)
• #pc: In picas, which are 12 points.
• #px: Explicitly in pixels (which remain 2 OS units)
• #in: In inches, which are 72 pixels.
• #cm: In centimetres, which are 28.3125 pixels.
• #em: In multiples of the 'em' size of the plain base font in the slide; the size will differ in the x and y dimentions.
• #%: In multiples of the space available; the size will differ in the x and y dimentions. Because the size depends on the context in which it is used, this percentage may be relative to two spaces:
  • the slide space, for content which is global to the slide
  • the remaining space in a block, for content which is inline with the body of the slide

Sizes may be specified as floating point values.

Supported markdown

The markdown supported is in line with most implementations but is limited - the MD4C library is used as the back end parser. The following elements of markdown are supported:

• Heading levels 1-3 indicated by lines prefixed by #, ##, ###.
• Inline code indicated by being surrounded by backticks.
• Italic, indicated by * surrounding text.
• Underline, indicated by _ surrounding text.
• Bold, indicated by ** surrounding text.
• Bold and italic, indicated by *** surrounding text.
• Strikethrough, indicated by ~ surrounding text.
• Ordered lists, indicated by a line starting with a 1. (or other digit sequence), which may be indented to indicate nesting levels.
• Unordered lists, indicated by a line starting with a * or -, which may be indented to indicate nesting levels.
• Block quotes, indicated by a line starting with a >.
• Code blocks delimited by three backticks.

The encoding used for rendering is the default alphabet (no specific alphabet is selected by the Font system at the current time).

Unsupported markdown

Any features not documented above are not supported, though partial support may exist within the system. Non-exhaustively, the following are not supported:

• Tables in any form.
• Wiki links and task lists.
• HTML blocks.
• Latex maths specifications.
• HTML entities.
• Nested quote blocks don't work as expected.

The incremental slide format (two hyphens, --) used by Remark is not supported by the tool.