X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=theme.rst;h=04146e8fce0003e701d66566419fb4ec869bf65d;hb=f2fb154081bf8d73aa8b750132fb17ba0fda12a9;hp=655329e840aa168d810f6b6fac976eb1b3e4fe85;hpb=619d8a89f87a555aabdedb9c60a9ac2902fca18a;p=nageru-docs diff --git a/theme.rst b/theme.rst index 655329e..04146e8 100644 --- a/theme.rst +++ b/theme.rst @@ -30,7 +30,7 @@ is a library for high-quality, high-performance video filters, and Nageru's themes can use a simplified version of Movit's API where most of the low-level details are abstracted away. -Every frame, the theme choses a chain and a set of parameters to it, +Every frame, the theme chooses a chain and a set of parameters to it, based on what it thinks the picture should look like. Every chain consists of a set of *inputs* (which can be either live video streams or static pictures) and then a set of operators or *effects* to combine @@ -55,7 +55,7 @@ the screen, and in this case, that would be the input):: Note the “hq” parameter. Every chain needs to be able to run in two situations: Both for the stream output (the ”live” pane) and for the preview -displays (the big “preview” pane and the smaller ones). The details have +displays (the big “preview” pane and the :ref:`channels `). The details have to do with Nageru internals (high-quality chains need to have an additional Y'CbCr output), but the distinction is also useful for themes. In particular, some operations, like scaling, can be done in various quality levels, @@ -67,6 +67,7 @@ and then scaled down for the GUI. Preview chains are rendered in exactly the resolution required, although of course, intermediate steps could be bigger. + Setting parameters, and the get_chain entry point ------------------------------------------------- @@ -228,6 +229,8 @@ the transition is over and changes back to showing only one input (presumably the new one). +.. _channels: + Channels -------- @@ -317,6 +320,8 @@ Transitions involving scenes tend to be the most complicated parts of the theme logic, but also make for the most distinct parts of your visual look. +.. _images: + Image inputs ------------ @@ -327,7 +332,7 @@ were created like this:: input = chain:add_live_input(false, deint) -Image inputs are instead created by instantiating **ImageInput** and +Image inputs are instead created by instantiating *ImageInput* and adding them manually to the chain:: input = chain:add_effect(ImageInput.new("bg.jpeg")) @@ -340,3 +345,42 @@ so if you update the file on-disk, it will be available in Nageru without a restart. (If the file contains an error, the update will be ignored.) This allows you to e.g. have simple message overlays that you can change without restarting Nageru. + + +.. _menus: + +Theme menus +----------- + +Complicated themes, especially those dealing with :doc:`HTML inputs `, +may have needs for user control that go beyond those of transition buttons. +(An obvious example may be “reload the HTML file”.) For this reason, +themes can also set simple *theme menus*, which are always visible +no matter what inputs are chosen. + +If a theme chooses to set a theme menu, it will be available on the +main menu bar under “Theme”; if not, it will be hidden. You can set +the menu at startup or at any other point, using a simple series of +labels and function references:: + + function modify_aspect() + -- Your code goes here. + end + + function reload_html() + html_input:reload() + end + + ThemeMenu.set( + { "Change &aspect", modify_aspect }, + { "&Reload overlay", reload_html } + ) + +When the user chooses a menu entry, the given Lua function will +automatically be called. There are no arguments nor return values. + +There currently is no support for checkboxes, submenus, input boxes +or the likes. However, do note that since the theme is written in unrestricted +Lua, so you can use e.g. `lua-http `_ +to listen for external connections and accept more complicated inputs +from those.