Add gamma to QViewport's API

Change-Id: Ieced911cf1e51c0befc5ce91e8529a421b5c5a80
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

5 files changed, 56 insertions, 2 deletions

diff --git a/src/render/framegraph/qviewport.cpp b/src/render/framegraph/qviewport.cpp
index a78e260a5..8c1ebe67c 100644
--- a/src/render/framegraph/qviewport.cpp
+++ b/src/render/framegraph/qviewport.cpp
@@ -50,6 +50,7 @@ namespace Qt3DRender {
 QViewportPrivate::QViewportPrivate()
     : QFrameGraphNodePrivate()
     , m_normalizedRect(QRectF(0.0f, 0.0f, 1.0f, 1.0f))
+    , m_gamma(2.2f)
 {
 }
 
@@ -62,7 +63,8 @@ QViewportPrivate::QViewportPrivate()
     \inherits Qt3DRender::QFrameGraphNode
 
     Qt3DRender::QViewport of the scene specifies at which portion of the render surface Qt3D
-    is rendering to. Area outside the viewport is left untouched.
+    is rendering to. Area outside the viewport is left untouched. It also controls global parameters
+    to the rendering in that viewport like gamma.
  */
 
 /*!
@@ -74,7 +76,8 @@ QViewportPrivate::QViewportPrivate()
     \brief A viewport on the Qt3D Scene
 
     Viewport of the scene specifies at which portion of the render surface Qt3D is
-    rendering to. Area outside the viewport is left untouched.
+    rendering to. Area outside the viewport is left untouched. It also controls global parameters
+    to the rendering in that viewport like gamma.
  */
 
 /*!
@@ -86,6 +89,12 @@ QViewportPrivate::QViewportPrivate()
  */
 
 /*!
+    \qmlproperty rect Viewport::gamma
+
+    Specifies the gamma factor for the viewport. The default is 2.2 which should give proper result on most screens.
+ */
+
+/*!
     Constructs QViewport with given \a parent.
  */
 QViewport::QViewport(QNode *parent)
@@ -111,6 +120,12 @@ QRectF QViewport::normalizedRect() const
     return d->m_normalizedRect;
 }
 
+float QViewport::gamma() const
+{
+    Q_D(const QViewport);
+    return d->m_gamma;
+}
+
 /*!
     \property QViewport::normalizedRect
 
@@ -127,12 +142,27 @@ void QViewport::setNormalizedRect(const QRectF &normalizedRect)
     }
 }
 
+/*!
+    \property QViewport::gamma
+
+    Specifies the gamma factor for the viewport. The default is 2.2 which should give proper result on most screens.
+ */
+void QViewport::setGamma(float gamma)
+{
+    Q_D(QViewport);
+    if (gamma != d->m_gamma) {
+        d->m_gamma = gamma;
+        emit gammaChanged(gamma);
+    }
+}
+
 Qt3DCore::QNodeCreatedChangeBasePtr QViewport::createNodeCreationChange() const
 {
     auto creationChange = QFrameGraphNodeCreatedChangePtr<QViewportData>::create(this);
     auto &data = creationChange->data;
     Q_D(const QViewport);
     data.normalizedRect = d->m_normalizedRect;
+    data.gamma = d->m_gamma;
     return creationChange;
 }
 
diff --git a/src/render/framegraph/qviewport.h b/src/render/framegraph/qviewport.h
index 5959ed791..abe423cf4 100644
--- a/src/render/framegraph/qviewport.h
+++ b/src/render/framegraph/qviewport.h
@@ -54,18 +54,22 @@ class QT3DRENDERSHARED_EXPORT QViewport : public QFrameGraphNode
 {
     Q_OBJECT
     Q_PROPERTY(QRectF normalizedRect READ normalizedRect WRITE setNormalizedRect NOTIFY normalizedRectChanged)
+    Q_PROPERTY(float gamma READ gamma WRITE setGamma NOTIFY gammaChanged)
 
 public:
     explicit QViewport(Qt3DCore::QNode *parent = nullptr);
     ~QViewport();
 
     QRectF normalizedRect() const;
+    float gamma() const;
 
 public Q_SLOTS:
     void setNormalizedRect(const QRectF& normalizedRect);
+    void setGamma(float gamma);
 
 Q_SIGNALS:
     void normalizedRectChanged(const QRectF& normalizedRect);
+    void gammaChanged(float gamma);
 
 protected:
     explicit QViewport(QViewportPrivate &dd, Qt3DCore::QNode *parent = nullptr);
diff --git a/src/render/framegraph/qviewport_p.h b/src/render/framegraph/qviewport_p.h
index 790cd3d06..4c82f38b3 100644
--- a/src/render/framegraph/qviewport_p.h
+++ b/src/render/framegraph/qviewport_p.h
@@ -67,11 +67,13 @@ public :
     Q_DECLARE_PUBLIC(QViewport)
     QRectF m_normalizedRect;
     QColor m_clearColor;
+    float m_gamma;
 };
 
 struct QViewportData
 {
     QRectF normalizedRect;
+    float gamma;
 };
 
 } // namespace Qt3DRender
diff --git a/src/render/framegraph/viewportnode.cpp b/src/render/framegraph/viewportnode.cpp
index ccdb68918..c16a660b0 100644
--- a/src/render/framegraph/viewportnode.cpp
+++ b/src/render/framegraph/viewportnode.cpp
@@ -55,6 +55,7 @@ ViewportNode::ViewportNode()
     , m_yMin(0.0f)
     , m_xMax(1.0f)
     , m_yMax(1.0f)
+    , m_gamma(2.2f)
 {
 }
 
@@ -67,6 +68,7 @@ void ViewportNode::initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr
     m_xMax = data.normalizedRect.width();
     m_yMin = data.normalizedRect.y();
     m_yMax = data.normalizedRect.height();
+    m_gamma = data.gamma;
 }
 
 float ViewportNode::xMin() const
@@ -106,6 +108,16 @@ void ViewportNode::setYMax(float yMax)
     m_yMax = yMax;
 }
 
+float ViewportNode::gamma() const
+{
+    return m_gamma;
+}
+
+void ViewportNode::setGamma(float gamma)
+{
+    m_gamma = gamma;
+}
+
 void ViewportNode::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e)
 {
     if (e->type() == PropertyUpdated) {
@@ -116,6 +128,8 @@ void ViewportNode::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e)
             setYMin(normalizedRect.y());
             setXMax(normalizedRect.width());
             setYMax(normalizedRect.height());
+        } else if (propertyChange->propertyName() == QByteArrayLiteral("gamma")) {
+            setGamma(propertyChange->value().toFloat());
         }
         markDirty(AbstractRenderer::AllDirty);
     }
diff --git a/src/render/framegraph/viewportnode_p.h b/src/render/framegraph/viewportnode_p.h
index 882aa4d86..85003ff36 100644
--- a/src/render/framegraph/viewportnode_p.h
+++ b/src/render/framegraph/viewportnode_p.h
@@ -81,6 +81,9 @@ public:
     float yMax() const;
     void setYMax(float yMax);
 
+    float gamma() const;
+    void setGamma(float gamma);
+
     void sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e) Q_DECL_OVERRIDE;
 
 private:
@@ -90,6 +93,7 @@ private:
     float m_yMin;
     float m_xMax;
     float m_yMax;
+    float m_gamma;
 };
 
 QRectF computeViewport(const QRectF &childViewport, const ViewportNode *parentViewport);