Pass the current output geometry to ScreenPaintData

Summary:
On Wayland per output rendering is performed and paintScreen is invoked
for every output. Some effects need the information which output is
currently being rendered as otherwise e.g. FBO access could fail.

This change adds the current output geometry to ScreenPaintData. On X11
(all outputs one geometry) this information is not set and a null rect
is returned. That way the effects can also easily check which rendering
mode is used.

Reviewers: #kwin, #plasma_on_wayland

Subscribers: plasma-devel, kwin

Tags: #plasma_on_wayland, #kwin

Differential Revision: https://phabricator.kde.org/D3058

autotests/test_screen_paint_data.cpp

@@ -20,6 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <kwineffects.h>
 
+#include <QMatrix4x4>
 #include <QtGui/QVector2D>
 #include <QVector3D>
 
@@ -57,11 +58,12 @@ void TestScreenPaintData::testCtor()
     QCOMPARE(data.rotationAngle(), 0.0);
     QCOMPARE(data.rotationOrigin(), QVector3D());
     QCOMPARE(data.rotationAxis(), QVector3D(0.0, 0.0, 1.0));
+    QCOMPARE(data.outputGeometry(), QRect());
 }
 
 void TestScreenPaintData::testCopyCtor()
 {
-    ScreenPaintData data;
+    ScreenPaintData data(QMatrix4x4(), QRect(10, 20, 30, 40));
     ScreenPaintData data2(data);
     // no value had been changed
     QCOMPARE(data2.xScale(), 1.0);
@@ -74,6 +76,7 @@ void TestScreenPaintData::testCopyCtor()
     QCOMPARE(data2.rotationAngle(), 0.0);
     QCOMPARE(data2.rotationOrigin(), QVector3D());
     QCOMPARE(data2.rotationAxis(), QVector3D(0.0, 0.0, 1.0));
+    QCOMPARE(data2.outputGeometry(), QRect(10, 20, 30, 40));
 
     data2.setScale(QVector3D(0.5, 2.0, 3.0));
     data2.translate(0.5, 2.0, 3.0);
@@ -97,13 +100,14 @@ void TestScreenPaintData::testCopyCtor()
 void TestScreenPaintData::testAssignmentOperator()
 {
     ScreenPaintData data;
-    ScreenPaintData data2;
+    ScreenPaintData data2(QMatrix4x4(), QRect(10, 20, 30, 40));
 
     data2.setScale(QVector3D(0.5, 2.0, 3.0));
     data2.translate(0.5, 2.0, 3.0);
     data2.setRotationAngle(45.0);
     data2.setRotationOrigin(QVector3D(1.0, 2.0, 3.0));
     data2.setRotationAxis(QVector3D(1.0, 1.0, 0.0));
+    QCOMPARE(data2.outputGeometry(), QRect(10, 20, 30, 40));
 
     data = data2;
     // data and data2 should be the same
@@ -117,6 +121,7 @@ void TestScreenPaintData::testAssignmentOperator()
     QCOMPARE(data.rotationAngle(), 45.0);
     QCOMPARE(data.rotationOrigin(), QVector3D(1.0, 2.0, 3.0));
     QCOMPARE(data.rotationAxis(), QVector3D(1.0, 1.0, 0.0));
+    QCOMPARE(data.outputGeometry(), QRect(10, 20, 30, 40));
     // data 2
     QCOMPARE(data2.xScale(), 0.5);
     QCOMPARE(data2.yScale(), 2.0);

libkwineffects/kwineffects.cpp

@@ -435,6 +435,7 @@ class ScreenPaintData::Private
 {
 public:
     QMatrix4x4 projectionMatrix;
+    QRect outputGeometry;
 };
 
 ScreenPaintData::ScreenPaintData()
@@ -443,11 +444,12 @@ ScreenPaintData::ScreenPaintData()
 {
 }
 
-ScreenPaintData::ScreenPaintData(const QMatrix4x4 &projectionMatrix)
+ScreenPaintData::ScreenPaintData(const QMatrix4x4 &projectionMatrix, const QRect &outputGeometry)
     : PaintData()
     , d(new Private())
 {
     d->projectionMatrix = projectionMatrix;
+    d->outputGeometry = outputGeometry;
 }
 
 ScreenPaintData::~ScreenPaintData() = default;
@@ -464,6 +466,7 @@ ScreenPaintData::ScreenPaintData(const ScreenPaintData &other)
     setRotationAxis(other.rotationAxis());
     setRotationAngle(other.rotationAngle());
     d->projectionMatrix = other.d->projectionMatrix;
+    d->outputGeometry = other.d->outputGeometry;
 }
 
 ScreenPaintData &ScreenPaintData::operator=(const ScreenPaintData &rhs)
@@ -478,6 +481,7 @@ ScreenPaintData &ScreenPaintData::operator=(const ScreenPaintData &rhs)
     setRotationAxis(rhs.rotationAxis());
     setRotationAngle(rhs.rotationAngle());
     d->projectionMatrix = rhs.d->projectionMatrix;
+    d->outputGeometry = rhs.d->outputGeometry;
     return *this;
 }
 
@@ -530,6 +534,11 @@ QMatrix4x4 ScreenPaintData::projectionMatrix() const
     return d->projectionMatrix;
 }
 
+QRect ScreenPaintData::outputGeometry() const
+{
+    return d->outputGeometry;
+}
+
 //****************************************
 // Effect
 //****************************************

libkwineffects/kwineffects.h

@@ -2547,7 +2547,7 @@ class KWINEFFECTS_EXPORT ScreenPaintData : public PaintData
 {
 public:
     ScreenPaintData();
-    ScreenPaintData(const QMatrix4x4 &projectionMatrix);
+    ScreenPaintData(const QMatrix4x4 &projectionMatrix, const QRect &outputGeometry = QRect());
     ScreenPaintData(const ScreenPaintData &other);
     virtual ~ScreenPaintData();
     /**
@@ -2599,6 +2599,16 @@ public:
      * @since 5.6
      **/
     QMatrix4x4 projectionMatrix() const;
+
+    /**
+     * The geometry of the currently rendered output.
+     * Only set for per-output rendering (e.g. Wayland).
+     *
+     * This geometry can be used as a hint about the native window the OpenGL context
+     * is bound. OpenGL calls need to be translated to this geometry.
+     * @since 5.9
+     **/
+    QRect outputGeometry() const;
 private:
     class Private;
     QScopedPointer<Private> d;

scene.cpp

@@ -107,7 +107,7 @@ Scene::~Scene()
 
 // returns mask and possibly modified region
 void Scene::paintScreen(int* mask, const QRegion &damage, const QRegion &repaint,
-                        QRegion *updateRegion, QRegion *validRegion, const QMatrix4x4 &projection)
+                        QRegion *updateRegion, QRegion *validRegion, const QMatrix4x4 &projection, const QRect &outputGeometry)
 {
     const QSize &screenSize = screens()->size();
     const QRegion displayRegion(0, 0, screenSize.width(), screenSize.height());
@@ -147,7 +147,7 @@ void Scene::paintScreen(int* mask, const QRegion &damage, const QRegion &repaint
         paintBackground(region);
     }
 
-    ScreenPaintData data(projection);
+    ScreenPaintData data(projection, outputGeometry);
     effects->paintScreen(*mask, region, data);
 
     foreach (Window *w, stacking_order) {

scene.h

@@ -173,7 +173,7 @@ protected:
     void clearStackingOrder();
     // shared implementation, starts painting the screen
     void paintScreen(int *mask, const QRegion &damage, const QRegion &repaint,
-                     QRegion *updateRegion, QRegion *validRegion, const QMatrix4x4 &projection = QMatrix4x4());
+                     QRegion *updateRegion, QRegion *validRegion, const QMatrix4x4 &projection = QMatrix4x4(), const QRect &outputGeometry = QRect());
     friend class EffectsHandlerImpl;
     // called after all effects had their paintScreen() called
     void finalPaintScreen(int mask, QRegion region, ScreenPaintData& data);

scene_opengl.cpp

@@ -710,7 +710,7 @@ qint64 SceneOpenGL::paint(QRegion damage, ToplevelList toplevels)
 
             int mask = 0;
             updateProjectionMatrix();
-            paintScreen(&mask, damage.intersected(geo), repaint, &update, &valid, projectionMatrix());   // call generic implementation
+            paintScreen(&mask, damage.intersected(geo), repaint, &update, &valid, projectionMatrix(), geo);   // call generic implementation
 
             GLVertexBuffer::streamingBuffer()->endOfFrame();