From a86a7e7b3cae90893de1280b3c886c80cb56c116 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Fri, 11 Sep 2015 13:31:41 +0200
Subject: [PATCH] Add a placement strategy for transient ShellClients

A transient ShellClient has an offset position to the parent surface.
Use this to position the ShellClient properly.

This fixes the random placement of menus.
---
 abstract_client.cpp | 10 ++++++++++
 abstract_client.h   |  9 +++++++++
 placement.cpp       |  8 ++++++++
 placement.h         |  1 +
 shell_client.cpp    | 10 ++++++++++
 shell_client.h      |  2 ++
 6 files changed, 40 insertions(+)

diff --git a/abstract_client.cpp b/abstract_client.cpp
index a1c66a710e..0fde7e0d12 100644
--- a/abstract_client.cpp
+++ b/abstract_client.cpp
@@ -812,4 +812,14 @@ AbstractClient *AbstractClient::transientFor()
     return m_transientFor;
 }
 
+bool AbstractClient::hasTransientPlacementHint() const
+{
+    return false;
+}
+
+QPoint AbstractClient::transientPlacementHint() const
+{
+    return QPoint();
+}
+
 }
diff --git a/abstract_client.h b/abstract_client.h
index 3bdee8c170..993e6597fe 100644
--- a/abstract_client.h
+++ b/abstract_client.h
@@ -247,6 +247,15 @@ public:
     // TODO: remove boolean trap
     virtual AbstractClient *findModal(bool allow_itself = false) = 0;
     virtual bool isTransient() const;
+    /**
+     * @returns Whether there is a hint available to place the AbstractClient on it's parent, default @c false.
+     * @see transientPlacementHint
+     **/
+    virtual bool hasTransientPlacementHint() const;
+    /**
+     * @returns The recommended position of the transient in parent coordinates
+     **/
+    virtual QPoint transientPlacementHint() const;
     const AbstractClient* transientFor() const;
     AbstractClient* transientFor();
     /**
diff --git a/placement.cpp b/placement.cpp
index ff1a06b095..1b4873fe09 100644
--- a/placement.cpp
+++ b/placement.cpp
@@ -72,6 +72,8 @@ void Placement::place(AbstractClient* c, QRect& area)
         placeOnMainWindow(c, area);   // on mainwindow, if any, otherwise centered
     else if (c->isOnScreenDisplay() || c->isNotification())
         placeOnScreenDisplay(c, area);
+    else if (c->isTransient() && c->hasTransientPlacementHint())
+        placeTransient(c);
     else
         place(c, area, options->placement());
 }
@@ -492,6 +494,12 @@ void Placement::placeOnScreenDisplay(AbstractClient* c, QRect& area)
     c->move(QPoint(x, y));
 }
 
+void Placement::placeTransient(AbstractClient *c)
+{
+    // TODO: apply sanity checks?
+    c->move(c->transientFor()->pos() + c->transientPlacementHint());
+}
+
 void Placement::placeDialog(AbstractClient* c, QRect& area, Policy nextPlacement)
 {
     placeOnMainWindow(c, area, nextPlacement);
diff --git a/placement.h b/placement.h
index 87c1dfa052..f50f35c012 100644
--- a/placement.h
+++ b/placement.h
@@ -92,6 +92,7 @@ private:
     void place(AbstractClient* c, QRect& area, Policy policy, Policy nextPlacement = Unknown);
     void placeUnderMouse(AbstractClient* c, QRect& area, Policy next = Unknown);
     void placeOnMainWindow(AbstractClient* c, QRect& area, Policy next = Unknown);
+    void placeTransient(AbstractClient *c);
     QRect checkArea(const AbstractClient*c, const QRect& area);
 
     //CT needed for cascading+
diff --git a/shell_client.cpp b/shell_client.cpp
index 975ae473e0..beef5c2ca3 100644
--- a/shell_client.cpp
+++ b/shell_client.cpp
@@ -726,4 +726,14 @@ void ShellClient::setTransient()
     setTransientFor(waylandServer()->findClient(s.data()));
 }
 
+bool ShellClient::hasTransientPlacementHint() const
+{
+    return isTransient() && transientFor() != nullptr;
+}
+
+QPoint ShellClient::transientPlacementHint() const
+{
+    return m_shellSurface->transientOffset();
+}
+
 }
diff --git a/shell_client.h b/shell_client.h
index 32f70a8c28..cf770531ad 100644
--- a/shell_client.h
+++ b/shell_client.h
@@ -112,6 +112,8 @@ public:
     bool isInitialPositionSet() const;
 
     bool isTransient() const override;
+    bool hasTransientPlacementHint() const override;
+    QPoint transientPlacementHint() const override;
 
 protected:
     void addDamage(const QRegion &damage) override;