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-rw-r--r--libwindowmanager/doc/CMakeLists.txt4
-rw-r--r--libwindowmanager/doc/GNUmakefile7
-rw-r--r--libwindowmanager/doc/LibWindowmanager.md250
-rw-r--r--libwindowmanager/doc/LibWindowmanager.txt238
4 files changed, 499 insertions, 0 deletions
diff --git a/libwindowmanager/doc/CMakeLists.txt b/libwindowmanager/doc/CMakeLists.txt
new file mode 100644
index 0000000..da59a0c
--- /dev/null
+++ b/libwindowmanager/doc/CMakeLists.txt
@@ -0,0 +1,4 @@
+install(
+ FILES LibWindowmanager.md
+ DESTINATION ${CMAKE_INSTALL_DOCDIR}
+ COMPONENT "development")
diff --git a/libwindowmanager/doc/GNUmakefile b/libwindowmanager/doc/GNUmakefile
new file mode 100644
index 0000000..d878cc4
--- /dev/null
+++ b/libwindowmanager/doc/GNUmakefile
@@ -0,0 +1,7 @@
+all: LibWindowmanager.html
+
+LibWindowmanager.html: LibWindowmanager.txt
+ asciidoc -a max-width=55em $^
+
+clean:
+ rm -f LibWindowmanager.html
diff --git a/libwindowmanager/doc/LibWindowmanager.md b/libwindowmanager/doc/LibWindowmanager.md
new file mode 100644
index 0000000..b855081
--- /dev/null
+++ b/libwindowmanager/doc/LibWindowmanager.md
@@ -0,0 +1,250 @@
+Introduction
+============
+
+The LibWindowmanager library provides a simple interface to manipulate and
+query the state of the window manager application framework binding.
+It is needs to be integrated and called from the client application.
+
+Intended audience
+-----------------
+
+This document is intended to be useful to application developers.
+
+Scope of this Document
+----------------------
+
+This document describes the singleton class interface to the *Window
+Manager* binding service.
+
+class LibWindowmanager
+===============
+
+This is the public interface of the class `LibWindowmanager`. Private members
+and methods are not reproduced as they will not affect usage of the
+class by client applications.
+
+ class LibWindowmanager
+ {
+ public:
+ static LibWindowmanager &instance();
+
+ int init(int port, char const *token);
+
+ // WM API
+ int requestSurface(const char *label);
+ int activateSurface(const char *label);
+ int deactivateSurface(const char *label);
+ int endDraw(const char *label);
+
+ enum EventType {
+ Event_Active,
+ Event_Inactive,
+ Event_Visible,
+ Event_Invisible,
+ Event_SyncDraw,
+ Event_FlushDraw,
+ };
+
+ void set_event_handler(enum EventType et,
+ std::function<void(char const *label)> f);
+ };
+
+Errors
+------
+
+Methods returning an `int` signal successful operation when returning
+`0`. In case of an error, an error value is returned as a negative errno
+value. E.g. `-EINVAL` to signal that some input value was invalid.
+
+Additionally, logging of error messages is done on the standard error
+file descriptor to help debugging the issue.
+
+Labels
+------
+
+Surface labels are any valid strings. For `requestSurface()` these
+strings must match the *Window Manager* configuration in order to be
+allowed to be displayed on one layer or the other. For all other calls
+the label must match the exact name of a requested surface.
+
+Methods
+-------
+
+### LibWindowmanager::init(port, token)
+
+Initialize the Binding communication.
+
+The `token` parameter is a string consisting of only alphanumeric characters.
+If these conditions are not met, the LibWindowmanager instance will not initialize,
+i.e. this call will return `-EINVAL`.
+
+The `port` parameter is the port the afb daemon is listening on, an
+invalid port will lead to a failure of the call and return `-EINVAL`.
+
+### LibWindowmanager::requestSurface(label)
+
+This method requests a surface with the label given from the *Window
+Manager*. It will return `0` for a successful surface request, and
+`-errno` on failure. Additionally, on the standard error, messages are
+logged to help debgging the issue.
+
+### LibWindowmanager::activateSurface(label)
+
+This method is mainly intended for *manager* applications that control
+other applications (think an application manager or the *HomeScreen*).
+It instructs the window manager to activate the surface with the given
+*label*.
+
+This method only is effective after the actual window or surface was
+created by the application.
+
+### LibWindowmanager::deactivateSurface(label)
+
+This method is mainly intended for *manager* applications that control
+other applications. It instructs the window manager to deactivate the
+surface associated with the given label. Note, that deactivating a
+surface also means to implicitly activate another (the last active or if
+not available *main surface* or *HomeScreen*.)
+
+This method only is effective after the actual window or surface was
+created by the application.
+
+### LibWindowmanager::endDraw(label)
+
+This function is called from a client application when it is done
+drawing its surface content.
+
+It is not crucial to make this call at every time a drawing is finished
+- it is mainly intended to allow the window manager to synchronize
+drawing in case of layout switch. The exact semantics are explained in
+the next [Events](#_events) Section.
+
+### LibWindowmanager::set\_event\_handler(et, func)
+
+This method needs to be used to register event handlers for the WM
+events described in the EventType enum. Only one hendler for each
+EventType is possible, i.e. if it is called multiple times with the same
+EventType the previous handler will be replaced.
+
+The `func` handler functions will receive the label of the surface this
+event is targeted at.
+
+See Section [Events](#_events) for mor detailed information about event
+delivery to client applications.
+
+Usage
+-----
+
+### Initialization of LibWindowmanager
+
+Before usage of the LibWindowmanager, the method `init()` must be
+called once, it will return `-errno` in case of en error and log
+diagnostic messages to stderr.
+
+### Request a surface
+
+When creating a surface with *Qt* - it is necessary to request a surface
+from the WM, internally this will communicate with the window manager
+binding. Only after `requestSurface()` was successful, a surface should
+be created.
+
+This is also true for *QML* aplications, where only after the
+`requestSurface()` should the load of the resource be done. The method
+returns `0` after the surface was requested successfully.
+
+#### Workings of requestSurface()
+
+`LibWindowmanager::requestSurface()` calls the AFB binding verb
+`requestsurface` of the `windowmanager` API. This API call will return a
+numeric ID to be used when creating the surface. This ID is never
+explicitly returned to the client application, instead, it is set in the
+application environment in order for *Qt* to then use it when creating
+the surface.
+
+With the current *Qt* implementation this means, that only one surface
+will be available to client applications, as subsequent windows will
+increment this numeric ID internally - which then will lead to IDs that
+cannot be known by the window manager as there is no direct
+communication from *Qt* to the WM.
+
+Events
+------
+
+Events are a way for the *Window Manager* to propagate information to
+client applications. It was vital for the project to implement a number
+of events, that mirror functionality that is already present in the
+wayland protocol.
+
+All events have the surface `label` as argument - a way to enable future
+multi-surface applications.
+
+As already stated above, this is currently not possible with the way
+*Qt* implements its surface ID setting.
+
+### Active and Inactive Events
+
+These events signal an application that it was activated or deactivated
+respectively. Usually this means it was switched visible - which means
+the surface will now be on the screen and therefor continue to render.
+
+### Visible and Invisible
+
+These events signal an application that it was switched to be visible or
+invisible respectively. These events too are handled implicitly through
+the wayland protocol by means of `wl_surface::enter` and
+`wl_surface::leave` events to the client.
+
+### SyncDraw and FlushDraw
+
+These events instruct applications that they should redraw their surface
+contents - again, this is handled implicitly by the wayland protocol.
+
+`SyncDraw` is sent to the application when it has to redraw its surface.
+
+`FlushDraw` is sent to the application when it should swap its buffers,
+that is *signal* the compositor that its surface contains new content.
+
+Example Use Case
+----------------
+
+In order to enable application to use the `WM` surface registration
+function the above described steps need to be implemented.
+
+As a minimal example the usage and initialization can look like the
+following.
+
+ // Assume a program argc and argv.
+ QGuiApplication app(argc, argv);
+
+ auto &wm = LibWindowmanager::instance();
+
+ // initialize the LibWindowmanager binding.
+ if(wm.init(1234, "wmtest") != 0) {
+ exit(EXIT_FAILURE);
+ }
+
+ // Request a surface label from the WM.
+ char const *surface_label = "AppMediaPlayer";
+ if (wm.requestSurface(surface_label) != 0) {
+ exit(EXIT_FAILURE);
+ }
+
+ // Register an Active event handler.
+ wm.set_event_handler(Event_Active,
+ [](char const *label) {
+ qDebug() << "Surface" << label << "got activated";
+ });
+
+ // Initialize application window
+ // ...
+
+ // request to activate the surface, this should usually
+ // not be done by the client application.
+ if (wm.activateSurface(surface_label) != 0) {
+ fprintf(stderr, "Could not activate the surface\n");
+ exit(EXIT_FAILURE);
+ }
+
+ // e.g. exec the qt application
+ app.exec();
+
diff --git a/libwindowmanager/doc/LibWindowmanager.txt b/libwindowmanager/doc/LibWindowmanager.txt
new file mode 100644
index 0000000..87394af
--- /dev/null
+++ b/libwindowmanager/doc/LibWindowmanager.txt
@@ -0,0 +1,238 @@
+= LibWindowmanager Library User Guide
+:doctype: book
+:toc:
+:icons:
+:data-uri:
+:lang: en
+:encoding: utf-8
+
+== Introduction
+The LibWindowmanager library provides a simple interface to manipulate and
+query the state of the window manager application framework binding.
+It is needs to be integrated and called from the client application.
+
+=== Intended audience
+This document is intended to be useful to application developers.
+
+=== Scope of this Document
+This document describes the singleton class interface to the _Window
+Manager_ binding service.
+
+== class LibWindowmanager
+This is the public interface of the class `LibWindowmanager`. Private members
+and methods are not reproduced as they will not affect usage of the
+class by client applications.
+
+---------------------------
+class LibWindowmanager
+{
+public:
+ static LibWindowmanager &instance();
+
+ int init(int port, char const *token);
+
+ // WM API
+ int requestSurface(const char *label);
+ int activateSurface(const char *label);
+ int deactivateSurface(const char *label);
+ int endDraw(const char *label);
+
+ enum EventType {
+ Event_Active,
+ Event_Inactive,
+ Event_Visible,
+ Event_Invisible,
+ Event_SyncDraw,
+ Event_FlushDraw,
+ };
+
+ void set_event_handler(enum EventType et,
+ std::function<void(char const *label)> f);
+};
+---------------------------
+
+=== Errors
+Methods returning an `int` signal successful operation when returning
+`0`. In case of an error, an error value is returned as a negative errno
+value. E.g. `-EINVAL` to signal that some input value was invalid.
+
+Additionally, logging of error messages is done on the standard error
+file descriptor to help debugging the issue.
+
+=== Labels
+Surface labels are any valid strings. For `requestSurface()` these strings
+must match the _Window Manager_ configuration in order to be allowed to
+be displayed on one layer or the other. For all other calls the label
+must match the exact name of a requested surface.
+
+=== Methods
+
+==== LibWindowmanager::init(port, token)
+Initialize the Binding communication.
+
+The `token` parameter is a string consisting of only alphanumeric characters.
+If these conditions are not met, the LibWindowmanager instance will not initialize,
+i.e. this call will return `-EINVAL`.
+
+The `port` parameter is the port the afb daemon is listening on,
+an invalid port will lead to a failure of the call and return `-EINVAL`.
+
+==== LibWindowmanager::requestSurface(label)
+This method requests a surface with the label given from the _Window
+Manager_. It will return `0` for a successful surface request, and
+`-errno` on failure. Additionally, on the standard error, messages are
+logged to help debgging the issue.
+
+==== LibWindowmanager::activateSurface(label)
+This method is mainly intended for _manager_ applications that control
+other applications (think an application manager or the _HomeScreen_). It
+instructs the window manager to activate the surface with the given
+_label_.
+
+This method only is effective after the actual window or surface was
+created by the application.
+
+==== LibWindowmanager::deactivateSurface(label)
+This method is mainly intended for _manager_ applications that control
+other applications. It instructs the window manager to deactivate the
+surface associated with the given label. Note, that deactivating a
+surface also means to implicitly activate another (the last active or
+if not available _main surface_ or _HomeScreen_.)
+
+This method only is effective after the actual window or surface was
+created by the application.
+
+==== LibWindowmanager::endDraw(label)
+This function is called from a client application when it is done
+drawing its surface content.
+
+It is not crucial to make this call at every time a drawing is finished -
+it is mainly intended to allow the window manager to synchronize drawing
+in case of layout switch. The exact semantics are explained in the next
+<<_events,Events>> Section.
+
+==== LibWindowmanager::set_event_handler(et, func)
+This method needs to be used to register event handlers for the WM
+events described in the EventType enum. Only one hendler for each
+EventType is possible, i.e. if it is called multiple times with the same
+EventType the previous handler will be replaced.
+
+The `func` handler functions will receive the label of the surface this
+event is targeted at.
+
+See Section <<_events,Events>> for mor detailed information about event
+delivery to client applications.
+
+=== Usage
+
+==== Initialization of LibWindowmanager
+Before usage of the LibWindowmanager, the method `init()` must be
+called once, it will return `-errno` in case of en error and log diagnostic
+messages to stderr.
+
+==== Request a surface
+When creating a surface with _Qt_ - it is necessary to request a surface
+from the WM, internally this will communicate with the window manager
+binding. Only after `requestSurface()` was successful, a surface should
+be created.
+
+This is also true for _QML_ aplications, where only after the
+`requestSurface()` should the load of the resource be done. The method
+returns `0` after the surface was requested successfully.
+
+===== Workings of requestSurface()
+`LibWindowmanager::requestSurface()` calls the AFB binding verb
+`requestsurface` of the `windowmanager` API. This API call will return a
+numeric ID to be used when creating the surface. This ID is never
+explicitly returned to the client application, instead, it is set in the
+application environment in order for _Qt_ to then use it when creating the
+surface.
+
+.Remarks
+********************************
+With the current _Qt_ implementation this means, that only one surface
+will be available to client applications, as subsequent windows will
+increment this numeric ID internally - which then will lead to IDs that
+cannot be known by the window manager as there is no direct
+communication from _Qt_ to the WM.
+********************************
+
+=== Events
+Events are a way for the _Window Manager_ to propagate information to
+client applications. It was vital for the project to implement a number
+of events, that mirror functionality that is already present in the
+wayland protocol.
+
+All events have the surface `label` as argument - a way to enable future
+multi-surface applications.
+
+.Remarks
+**************************
+As already stated above, this is currently not possible with the way
+_Qt_ implements its surface ID setting.
+**************************
+
+==== Active and Inactive Events
+These events signal an application that it was activated or deactivated
+respectively. Usually this means it was switched visible - which means
+the surface will now be on the screen and therefor continue to render.
+
+==== Visible and Invisible
+These events signal an application that it was switched to be visible or
+invisible respectively. These events too are handled implicitly through
+the wayland protocol by means of `wl_surface::enter` and
+`wl_surface::leave` events to the client.
+
+==== SyncDraw and FlushDraw
+These events instruct applications that they should redraw their surface
+contents - again, this is handled implicitly by the wayland protocol.
+
+`SyncDraw` is sent to the application when it has to redraw its surface.
+
+`FlushDraw` is sent to the application when it should swap its buffers,
+that is _signal_ the compositor that its surface contains new content.
+
+=== Example Use Case
+In order to enable application to use the `WM` surface registration
+function the above described steps need to be implemented.
+
+As a minimal example the usage and initialization can look like the
+following.
+
+-----------------------
+ // Assume a program argc and argv.
+ QGuiApplication app(argc, argv);
+
+ auto &wm = LibWindowmanager::instance();
+
+ // initialize the LibWindowmanager binding.
+ if(wm.init(1234, "wmtest") != 0) {
+ exit(EXIT_FAILURE);
+ }
+
+ // Request a surface label from the WM.
+ char const *surface_label = "AppMediaPlayer";
+ if (wm.requestSurface(surface_label) != 0) {
+ exit(EXIT_FAILURE);
+ }
+
+ // Register an Active event handler.
+ wm.set_event_handler(Event_Active,
+ [](char const *label) {
+ qDebug() << "Surface" << label << "got activated";
+ });
+
+ // Initialize application window
+ // ...
+
+ // request to activate the surface, this should usually
+ // not be done by the client application.
+ if (wm.activateSurface(surface_label) != 0) {
+ fprintf(stderr, "Could not activate the surface\n");
+ exit(EXIT_FAILURE);
+ }
+
+ // e.g. exec the qt application
+ app.exec();
+
+// vim:set ft=asciidoc tw=72: