SlideField

SlideField is a text-based presentation software with its own interpreted language.

Installation

Requirements: ruby, sdl, sdl_ttf, freeimage

$ gem install slidefield

Usage

$ slidefield [options] [file ...]

Comments

% single-line comment
%{ multi-line
   comment %}

Variables

A variable can only be created once inside each object (with the = operator). However they can be modified freely using any other available operator. The type of the variable cannot be changed after the variable creation.

variable  = value
variable += value
variable -= value
variable *= value
variable /= value

Value types

Integers:

variable  = 42
variable += 2  % add
variable -= 10 % subtract
variable *= 6  % multiply
variable /= 10 % divide
% variable is 20

Character strings:

variable  = "hello"
variable += " world!\n" % append
variable -= "!"         % remove the bang
variable *= "3"         % multiply by 3
% variable is "hello world\nhello world\nhello world\n"

Size or point coordinates:

variable  = 2x4
variable += 100x80 % add
variable -= 10x0   % subtract
variable *= 3x4    % multiply
variable /= 2x2    % divide
% variable is 138x168

Colors (red, blue, green & alpha in hexadecimal notation):

variable  = #C0FF33FF
variable += #03003300 % add
variable -= #0C240055 % subtract
% variable is #B7DB66AA

Booleans:

variable = :true
opposite = :false

Variables can also store custom objects. See the 'Templates' section below.

Objects

Variables are bound to the object in which they are created into. Most SlideField object have reserved variables ("properties") with a predefined type. All properties are mandatory unless otherwise specified.

Nested objects inherit their parent's variables. All slide objects (marked as such in the list below) can be infinitely nested.

% Syntax:
\object_name
\object_name { ... }
\object_name value
\object_name value { ... }

The shortcut syntax \object value assigns value to the first property compatible with the value's type.

Object List

(Anywhere) Load another file at the current location:

\include "path/to/file.sfp"
\include {
  source = "path/to/file.sfp"
}

(Anywhere) Print debug information about any value to standard output:

\debug any_value

(Top-level, required, maximum 1) Configure the output window:

\layout 1920x1080
\layout {
  size = 1920x1080
  fullscreen = :true % optional
}

(Top-level, required) Create a slide:

\slide { ... }

(Slide) Animation between slides:

\animation "fade" { ... }
\animation {
  name = "fade"
  %{
  other possible values are:
  name = "slide right"
  name = "slide left"
  name = "slide down"
  name = "slide up"
  name = "zoom"
  %}
  duration = 400 % in ms (optional)
  enter = :true % optional
  leave = :true % optional
}

Note: The animation is applied only to nested objects.

(Slide) Add an image:

\image "path/to/image.png"
\image {
  source = "path/to/image.png"
  size = 0x0        % automatic if 0 (optional)
  color = #FFFFFFFF % color filter (optional)
  position = 0x0    % optional
  z_order = 0       % optional
}

(Slide) Add a rectangle:

\rect 100x100
\rect {
  size = 100x100
  fill = #FFFFFFFF % optional
  position = 0x0   % optional
  z_order = 0      % optional
}

(Slide) Play an audio file:

\song "path/to/audio.ogg"
\song {
  source = "path/to/audio.ogg"
  volume = 100 % optional
  loop = :true % optional
}

(Slide) Add text:

\text "Hello World!"
\text {
  content = "Hello World!"
  color = #FFFFFFFF % optional
  font = "sans"     % font name or path (optional)
  % font = "./my_font.ttf"
  height = 20       % font height in pixels (optional)
  width = 0         % maximum width (automatic if 0, optional)
  spacing = 0       % line spacing (optional)
  align = "left"    % optional
  %{
  other possible values are:
  align = "right"
  align = "center"
  align = "justify"
  %}
  position = 0x0 % optional
  z_order = 0    % optional
}

Filters

Filters are like methods in an object-oriented programming language. They can be chained infinitely.

variable = (filter)value
variable = (second_filter)(first_filter)value

Point to integer:

point = 1920x1080
x = (x)point
% x is 1920

y = (y)point
% y is 1080

Integer to point:

point = (x)1920
% point is 1920x0

point += (y)1080
% point is 1920x1080

Line count:

lines = (lines)"Lorem\nIpsum"
% lines is 2

Templates

Custom objects can be created using templates.

template_name = \object_name { ... }
\&template_name

% creation
slide_template = \slide {
  \image background { size = 1920x1080; }
  \text title { height = 72; }
}

% usage
\&slide_template {
  title = "Hello World!"
  background = "path/to/image.png"
}

Equivalent of the above example without using templates:

\slide {
  title = "Hello World!"
  background = "path/to/image.png"
  \image background { size = 1920x1080; }
  \text title { height = 72; }
}

Changelog

0.1

First public release

0.1.1

(un)load subsequent slides in background
greatly reduced memory usage and startup time
new 'enter' and 'leave' properties for \animation
support template inheritance

Contributing

Fork it
Create your feature branch (git checkout -b my-new-feature)
Test your changes (rake)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request

slidefield

Development

Runtime