From 2e7bc0df87845e2a5e22f2280f7047033fa83af3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Thu, 3 Dec 2015 09:50:40 +0100
Subject: [PATCH] [kwineffects] Pass screen projection matrix to EffectFrame

Exposes the current screen projection matrix in the render pass of
the EffectFrame, so that effects can make use of it.
---
 effects.cpp                    |  1 +
 effects.h                      |  4 ++++
 libkwineffects/kwineffects.cpp | 11 +++++++++++
 libkwineffects/kwineffects.h   | 16 ++++++++++++++++
 4 files changed, 32 insertions(+)

diff --git a/effects.cpp b/effects.cpp
index ebb7520bc5..ead8dedb68 100644
--- a/effects.cpp
+++ b/effects.cpp
@@ -1930,6 +1930,7 @@ void EffectFrameImpl::render(QRegion region, double opacity, double frameOpacity
         return; // Nothing to display
     }
     m_shader = NULL;
+    setScreenProjectionMatrix(static_cast<EffectsHandlerImpl*>(effects)->scene()->screenProjectionMatrix());
     effects->paintEffectFrame(this, region, opacity, frameOpacity);
 }
 
diff --git a/effects.h b/effects.h
index 1d0652a872..dfe6f12b07 100644
--- a/effects.h
+++ b/effects.h
@@ -226,6 +226,10 @@ public:
 
     KWayland::Server::Display *waylandDisplay() const override;
 
+    Scene *scene() const {
+        return m_scene;
+    }
+
 public Q_SLOTS:
     void slotCurrentTabAboutToChange(EffectWindow* from, EffectWindow* to);
     void slotTabAdded(EffectWindow* from, EffectWindow* to);
diff --git a/libkwineffects/kwineffects.cpp b/libkwineffects/kwineffects.cpp
index 0581dc4c17..b767f66712 100644
--- a/libkwineffects/kwineffects.cpp
+++ b/libkwineffects/kwineffects.cpp
@@ -1788,6 +1788,7 @@ public:
 
     bool crossFading;
     qreal crossFadeProgress;
+    QMatrix4x4 screenProjectionMatrix;
 };
 
 EffectFramePrivate::EffectFramePrivate()
@@ -1833,6 +1834,16 @@ void EffectFrame::enableCrossFade(bool enable)
     d->crossFading = enable;
 }
 
+QMatrix4x4 EffectFrame::screenProjectionMatrix() const
+{
+    return d->screenProjectionMatrix;
+}
+
+void EffectFrame::setScreenProjectionMatrix(const QMatrix4x4 &spm)
+{
+    d->screenProjectionMatrix = spm;
+}
+
 } // namespace
 
 #include "kwineffects.moc"
diff --git a/libkwineffects/kwineffects.h b/libkwineffects/kwineffects.h
index 5f72822ac0..4350e2b1c8 100644
--- a/libkwineffects/kwineffects.h
+++ b/libkwineffects/kwineffects.h
@@ -2937,6 +2937,22 @@ public:
      **/
     qreal crossFadeProgress() const;
 
+    /**
+     * Returns The projection matrix as used by the current screen painting pass
+     * including screen transformations.
+     *
+     * This matrix is only valid during a rendering pass started by render.
+     *
+     * @since 5.6
+     * @see render
+     * @see EffectsHandler::paintEffectFrame
+     * @see Effect::paintEffectFrame
+     **/
+    QMatrix4x4 screenProjectionMatrix() const;
+
+protected:
+    void setScreenProjectionMatrix(const QMatrix4x4 &projection);
+
 private:
     EffectFramePrivate* const d;
 };