layout: Add missing hooks for other surface roles

[src/agl-compositor.git] / doc / README.md

diff --git a/doc/README.md b/doc/README.md
index 0a9d110..090b1ae 100644 (file)
--- a/doc/README.md
+++ b/doc/README.md
@@ -9,6 +9,8 @@ implementation of the XDG shell protocol which underlying toolkits
 The former is used to provide back-ends and rendering support, besides
 implementing the wayland protocol.
 
+![high overview diagram of the compositor](arch_diagram.png "high overview diagram of the compositor")
+
 xdg-shell is currently de facto protocol for handling all window management
 related functionality. In order to avoid polluting the wayland protocol
 namespace, the XDG extension, together with some other useful protocols, like
@@ -163,7 +165,14 @@ needed to activate applications.
 ## Policy
 
 The compositor contains an API useful for defining policy rules.  It contains
-the bare minimum and installs, by default, an allow-all kind of engine.
+the bare minimum and installs, by default, an allow-all kind of engine. A
+deny-all policy engine exists and can be switched to by using
+`-Dpolicy-default=deny-all` build time option.
+
+For instance, in order to configure the compositor with that policy one could
+issue:
+
+       $ meson -Dprefix=/path/to/where/to/install/compositor -Dpolicy-default=deny-all build_directory
 
 Users wanting  to create their own policy engine should create a specialized
 version and use `struct ivi_policy_api` where they can install their own
@@ -184,9 +193,10 @@ control if policy rules (the next type) can be added or not. Finally, we have
 `ivi_policy_api::policy_rule_try_event()` which is executed for each policy
 rules currently added, by using the policy API `ivi_policy_add()`.
 
-Users can customize the hooks by using some sort of database to retrieve
-the application name to compare against, or incorporate some kind of policy
-rule engine.
+Users can customize the hooks by using some sort of database to retrieve the
+application name to compare against, or incorporate some kind of policy rule
+engine.  Alternatively, one can use the deny-all policy engine which allows the
+top panel applications to be used/displayed as permitted applications.
 
 ### Policy rules