Move selection labels to renderer from render items

Creating a new label on demand is fast enough, so we don't need to
store old labels. Storing labels unnecessarily leads to unchecked
use of graphics memory.

Optimized bar slices a bit by having separate class of render items
for slice items.

Change-Id: I5afdecfb3949393341b6c3eaefbc667c65da32e3
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>

7 files changed, 92 insertions, 61 deletions

diff --git a/src/datavisualization/engine/abstract3drenderer.cpp b/src/datavisualization/engine/abstract3drenderer.cpp
index e62f2a00..3122cf76 100644
--- a/src/datavisualization/engine/abstract3drenderer.cpp
+++ b/src/datavisualization/engine/abstract3drenderer.cpp
@@ -44,7 +44,8 @@ Abstract3DRenderer::Abstract3DRenderer(Abstract3DController *controller)
       m_devicePixelRatio(1.0f),
       m_selectionLabelDirty(true),
       m_clickPending(false),
-      m_clickedSeries(0)
+      m_clickedSeries(0),
+      m_selectionLabelItem(0)
 #ifdef DISPLAY_RENDER_SPEED
     , m_isFirstFrame(true),
       m_numFrames(0)
@@ -67,6 +68,7 @@ Abstract3DRenderer::~Abstract3DRenderer()
     delete m_textureHelper;
     delete m_cachedScene;
     delete m_cachedTheme;
+    delete m_selectionLabelItem;
 }
 
 void Abstract3DRenderer::initializeOpenGL()
@@ -450,4 +452,23 @@ void Abstract3DRenderer::fixGradientAndGenerateTexture(QLinearGradient *gradient
     *gradientTexture = m_textureHelper->createGradientTexture(*gradient);
 }
 
+LabelItem &Abstract3DRenderer::selectionLabelItem()
+{
+    if (!m_selectionLabelItem)
+        m_selectionLabelItem = new LabelItem;
+    return *m_selectionLabelItem;
+}
+
+void Abstract3DRenderer::setSelectionLabel(const QString &label)
+{
+    if (m_selectionLabelItem)
+        m_selectionLabelItem->clear();
+    m_selectionLabel = label;
+}
+
+QString &Abstract3DRenderer::selectionLabel()
+{
+    return m_selectionLabel;
+}
+
 QT_END_NAMESPACE_DATAVISUALIZATION
diff --git a/src/datavisualization/engine/abstract3drenderer_p.h b/src/datavisualization/engine/abstract3drenderer_p.h
index 4f5b644e..4eb8426f 100644
--- a/src/datavisualization/engine/abstract3drenderer_p.h
+++ b/src/datavisualization/engine/abstract3drenderer_p.h
@@ -101,6 +101,10 @@ public:
     inline void clearClickPending() { m_clickPending = false; }
     inline QAbstract3DSeries *clickedSeries() const { return m_clickedSeries; }
 
+    LabelItem &selectionLabelItem();
+    void setSelectionLabel(const QString &label);
+    QString &selectionLabel();
+
 signals:
     void needRender(); // Emit this if something in renderer causes need for another render pass.
     void requestShadowQuality(QAbstract3DGraph::ShadowQuality quality); // For automatic quality adjustments
@@ -146,6 +150,9 @@ protected:
     bool m_clickPending;
     QAbstract3DSeries *m_clickedSeries;
 
+    QString m_selectionLabel;
+    LabelItem *m_selectionLabelItem;
+
 #ifdef DISPLAY_RENDER_SPEED
     bool m_isFirstFrame;
     QTime m_lastFrameTime;
diff --git a/src/datavisualization/engine/bars3drenderer.cpp b/src/datavisualization/engine/bars3drenderer.cpp
index 3ec23476..be1be0dc 100644
--- a/src/datavisualization/engine/bars3drenderer.cpp
+++ b/src/datavisualization/engine/bars3drenderer.cpp
@@ -166,7 +166,6 @@ void Bars3DRenderer::updateData()
         m_seriesStart = -((float(seriesCount) - 1.0f) / 2.0f) * m_seriesStep;
     }
 
-
     if (m_keepSeriesUniform)
         m_seriesScaleZ = m_seriesScaleX;
     else
@@ -485,14 +484,14 @@ void Bars3DRenderer::drawSlicedScene()
 
     int sliceItemCount = m_sliceSelection.size();
     for (int bar = 0; bar < sliceItemCount; bar++) {
-        BarRenderItem *item = m_sliceSelection.at(bar);
-        if (!item)
+        const BarRenderSliceItem &item = m_sliceSelection.at(bar);
+        if (!item.value())
             continue;
 
         QQuaternion seriesRotation;
 
-        if (item->seriesIndex() != currentSeriesIndex) {
-            currentSeriesIndex = item->seriesIndex();
+        if (item.seriesIndex() != currentSeriesIndex) {
+            currentSeriesIndex = item.seriesIndex();
             currentSeries = &(m_visibleSeriesList.at(currentSeriesIndex));
             barObj = currentSeries->object();
             colorStyle = currentSeries->colorStyle();
@@ -524,7 +523,7 @@ void Bars3DRenderer::drawSlicedScene()
             seriesRotation = currentSeries->meshRotation();
         }
 
-        if (item->height() < 0)
+        if (item.height() < 0)
             glCullFace(GL_FRONT);
         else
             glCullFace(GL_BACK);
@@ -532,18 +531,18 @@ void Bars3DRenderer::drawSlicedScene()
         QMatrix4x4 MVPMatrix;
         QMatrix4x4 modelMatrix;
         QMatrix4x4 itModelMatrix;
-        QQuaternion barRotation = item->rotation();
-        GLfloat barPosY = item->translation().y() + barPosYAdjustment - zeroPosAdjustment;
+        QQuaternion barRotation = item.rotation();
+        GLfloat barPosY = item.translation().y() + barPosYAdjustment - zeroPosAdjustment;
 
         if (rowMode) {
-            barPosX = item->translation().x();
+            barPosX = item.translation().x();
         } else {
-            barPosX = -(item->translation().z()); // flip z; frontmost bar to the left
+            barPosX = -(item.translation().z()); // flip z; frontmost bar to the left
             barRotation *= ninetyDegreeRotation;
         }
 
         modelMatrix.translate(barPosX, barPosY, 0.0f);
-        modelMatrixScaler.setY(item->height());
+        modelMatrixScaler.setY(item.height());
 
         if (!seriesRotation.isIdentity())
             barRotation *= seriesRotation;
@@ -561,8 +560,8 @@ void Bars3DRenderer::drawSlicedScene()
         QVector3D barColor;
         GLuint gradientTexture = 0;
 
-        if (itemMode && m_visualSelectedBarPos.x() == item->position().x()
-                && m_visualSelectedBarPos.y() == item->position().y()) {
+        if (itemMode && m_visualSelectedBarPos.x() == item.position().x()
+                && m_visualSelectedBarPos.y() == item.position().y()) {
             if (colorStyleIsUniform)
                 barColor = highlightColor;
             else
@@ -574,7 +573,7 @@ void Bars3DRenderer::drawSlicedScene()
                 gradientTexture = baseGradientTexture;
         }
 
-        if (item->height() != 0) {
+        if (item.height() != 0) {
             // Set shader bindings
             barShader->setUniformValue(barShader->model(), modelMatrix);
             barShader->setUniformValue(barShader->nModel(),
@@ -584,7 +583,7 @@ void Bars3DRenderer::drawSlicedScene()
                 barShader->setUniformValue(barShader->color(), barColor);
             } else if (colorStyle == Q3DTheme::ColorStyleRangeGradient) {
                 barShader->setUniformValue(barShader->gradientHeight(),
-                                           (qAbs(item->height()) / m_gradientFraction));
+                                           (qAbs(item.height()) / m_gradientFraction));
             }
 
             // Draw the object
@@ -614,10 +613,10 @@ void Bars3DRenderer::drawSlicedScene()
 
     for (int labelNo = 0; labelNo <= lastLabel; labelNo++) {
         // Get labels from first series only
-        BarRenderItem *item = m_sliceSelection.at(labelNo);
-        m_dummyBarRenderItem.setTranslation(QVector3D(item->translation().x(),
+        const BarRenderSliceItem &item = m_sliceSelection.at(labelNo);
+        m_dummyBarRenderItem.setTranslation(QVector3D(item.translation().x(),
                                                       barLabelYPos,
-                                                      item->translation().z()));
+                                                      item.translation().z()));
         // Draw labels
         m_drawer->drawLabel(m_dummyBarRenderItem, *m_sliceCache->labelItems().at(labelNo),
                             viewMatrix, projectionMatrix, positionComp, sliceLabelRotation,
@@ -627,53 +626,53 @@ void Bars3DRenderer::drawSlicedScene()
     }
 
     for (int col = 0; col < sliceItemCount; col++) {
-        BarRenderItem *item = m_sliceSelection.at(col);
+        BarRenderSliceItem &item = m_sliceSelection[col];
 
         if (!sliceGridLabels) {
             // Draw values
-            if (item->height() != 0.0f || (!m_noZeroInRange && item->value() == 0.0f)) {
+            if (item.height() != 0.0f || (!m_noZeroInRange && item.value() == 0.0f)) {
                 // Create label texture if we need it
-                if (item->sliceLabel().isNull() || m_updateLabels) {
-                    item->setSliceLabel(generateValueLabel(m_axisCacheY.labelFormat(),
-                                                           item->value()));
-                    m_drawer->generateLabelItem(item->sliceLabelItem(), item->sliceLabel());
+                if (item.sliceLabel().isNull() || m_updateLabels) {
+                    item.setSliceLabel(generateValueLabel(m_axisCacheY.labelFormat(),
+                                                           item.value()));
+                    m_drawer->generateLabelItem(item.sliceLabelItem(), item.sliceLabel());
                     m_updateLabels = false;
                 }
-                Qt::AlignmentFlag alignment = (item->height() < 0) ? Qt::AlignBottom : Qt::AlignTop;
-                Drawer::LabelPosition labelPos = (item->height() < 0) ? Drawer::LabelBelow : Drawer::LabelOver;
-                m_dummyBarRenderItem.setTranslation(QVector3D(item->translation().x(),
+                Qt::AlignmentFlag alignment = (item.height() < 0) ? Qt::AlignBottom : Qt::AlignTop;
+                Drawer::LabelPosition labelPos = (item.height() < 0) ? Drawer::LabelBelow : Drawer::LabelOver;
+                m_dummyBarRenderItem.setTranslation(QVector3D(item.translation().x(),
                                                               barPosYAdjustment - zeroPosAdjustment
-                                                              + item->height(),
-                                                              item->translation().z()));
+                                                              + item.height(),
+                                                              item.translation().z()));
 
-                m_drawer->drawLabel(m_dummyBarRenderItem, item->sliceLabelItem(), viewMatrix,
+                m_drawer->drawLabel(m_dummyBarRenderItem, item.sliceLabelItem(), viewMatrix,
                                     projectionMatrix, zeroVector, sliceValueRotation,
-                                    item->height(), m_cachedSelectionMode, m_labelShader,
+                                    item.height(), m_cachedSelectionMode, m_labelShader,
                                     m_labelObj, activeCamera, false, false, labelPos,
                                     alignment, true);
             }
         } else {
             // Only draw value for selected item when grid labels are on
-            if (itemMode && m_visualSelectedBarPos.x() == item->position().x()
-                    && m_visualSelectedBarPos.y() == item->position().y()
-                    && item->seriesIndex() == m_visualSelectedBarSeriesIndex) {
+            if (itemMode && m_visualSelectedBarPos.x() == item.position().x()
+                    && m_visualSelectedBarPos.y() == item.position().y()
+                    && item.seriesIndex() == m_visualSelectedBarSeriesIndex) {
                 // Create label texture if we need it
-                if (item->sliceLabel().isNull() || m_updateLabels) {
-                    item->setSliceLabel(generateValueLabel(m_axisCacheY.labelFormat(),
-                                                           item->value()));
-                    m_drawer->generateLabelItem(item->sliceLabelItem(), item->sliceLabel());
+                if (item.sliceLabel().isNull() || m_updateLabels) {
+                    item.setSliceLabel(generateValueLabel(m_axisCacheY.labelFormat(),
+                                                           item.value()));
+                    m_drawer->generateLabelItem(item.sliceLabelItem(), item.sliceLabel());
                     m_updateLabels = false;
                 }
-                Qt::AlignmentFlag alignment = (item->height() < 0) ? Qt::AlignBottom : Qt::AlignTop;
-                Drawer::LabelPosition labelPos = (item->height() < 0) ? Drawer::LabelBelow : Drawer::LabelOver;
-                m_dummyBarRenderItem.setTranslation(QVector3D(item->translation().x(),
+                Qt::AlignmentFlag alignment = (item.height() < 0) ? Qt::AlignBottom : Qt::AlignTop;
+                Drawer::LabelPosition labelPos = (item.height() < 0) ? Drawer::LabelBelow : Drawer::LabelOver;
+                m_dummyBarRenderItem.setTranslation(QVector3D(item.translation().x(),
                                                               barPosYAdjustment - zeroPosAdjustment
-                                                              + item->height(),
-                                                              item->translation().z()));
+                                                              + item.height(),
+                                                              item.translation().z()));
 
-                m_drawer->drawLabel(m_dummyBarRenderItem, item->sliceLabelItem(), viewMatrix,
+                m_drawer->drawLabel(m_dummyBarRenderItem, item.sliceLabelItem(), viewMatrix,
                                     projectionMatrix, zeroVector, sliceValueRotation,
-                                    item->height(), m_cachedSelectionMode, m_labelShader,
+                                    item.height(), m_cachedSelectionMode, m_labelShader,
                                     m_labelObj, activeCamera, false, false, labelPos,
                                     alignment, true);
             }
@@ -1199,9 +1198,9 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
                             item.setPosition(QPoint(row, bar));
                             item.setSeriesIndex(series);
                             if (rowMode)
-                                m_sliceSelection[sliceSeriesAdjust + bar] = &item;
+                                m_sliceSelection[sliceSeriesAdjust + bar].setItem(item);
                             else
-                                m_sliceSelection[sliceSeriesAdjust + row] = &item;
+                                m_sliceSelection[sliceSeriesAdjust + row].setItem(item);
                         }
                         break;
                     }
@@ -1221,7 +1220,7 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
                                 item.setSeriesIndex(series);
                                 if (!m_sliceTitleItem && m_axisCacheZ.labelItems().size() > row)
                                     m_sliceTitleItem = m_axisCacheZ.labelItems().at(row);
-                                m_sliceSelection[sliceSeriesAdjust + bar] = &item;
+                                m_sliceSelection[sliceSeriesAdjust + bar].setItem(item);
                             }
                         }
                         break;
@@ -1248,7 +1247,7 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
                                 item.setSeriesIndex(series);
                                 if (!m_sliceTitleItem && m_axisCacheX.labelItems().size() > bar)
                                     m_sliceTitleItem = m_axisCacheX.labelItems().at(bar);
-                                m_sliceSelection[sliceSeriesAdjust + row] = &item;
+                                m_sliceSelection[sliceSeriesAdjust + row].setItem(item);
                             }
                         }
                         break;
@@ -1804,10 +1803,10 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
         // Print value of selected bar
         glDisable(GL_DEPTH_TEST);
         // Draw the selection label
-        LabelItem &labelItem = selectedBar->selectionLabelItem();
+        LabelItem &labelItem = selectionLabelItem();
         if (m_selectedBar != selectedBar || m_updateLabels || !labelItem.textureId()
                 || m_selectionLabelDirty) {
-            QString labelText = selectedBar->selectionLabel();
+            QString labelText = selectionLabel();
             if (labelText.isNull() || m_selectionLabelDirty) {
                 static const QString rowIndexTag(QStringLiteral("@rowIdx"));
                 static const QString rowLabelTag(QStringLiteral("@rowLabel"));
@@ -1851,7 +1850,7 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
                 labelText.replace(seriesNameTag,
                                   m_visibleSeriesList[m_visualSelectedBarSeriesIndex].name());
 
-                selectedBar->setSelectionLabel(labelText);
+                setSelectionLabel(labelText);
                 m_selectionLabelDirty = false;
             }
             m_drawer->generateLabelItem(labelItem, labelText);
@@ -1942,6 +1941,7 @@ void Bars3DRenderer::updateSelectedBar(const QPoint &position, const QBar3DSerie
     m_selectedBarPos = position;
     m_selectedBarSeries = series;
     m_selectionDirty = true;
+    m_selectionLabelDirty = true;
     m_visualSelectedBarSeriesIndex = -1;
 
     if (m_renderingArrays.isEmpty()) {
diff --git a/src/datavisualization/engine/bars3drenderer_p.h b/src/datavisualization/engine/bars3drenderer_p.h
index 89030b30..37ac2b76 100644
--- a/src/datavisualization/engine/bars3drenderer_p.h
+++ b/src/datavisualization/engine/bars3drenderer_p.h
@@ -60,7 +60,7 @@ private:
 
     // Internal state
     BarRenderItem *m_selectedBar; // points to renderitem array
-    QVector<BarRenderItem *> m_sliceSelection;
+    QVector<BarRenderSliceItem> m_sliceSelection;
     AxisRenderCache *m_sliceCache; // not owned
     const LabelItem *m_sliceTitleItem; // not owned
     bool m_xFlipped;
diff --git a/src/datavisualization/engine/drawer.cpp b/src/datavisualization/engine/drawer.cpp
index b70d7c0e..55a2c2a5 100644
--- a/src/datavisualization/engine/drawer.cpp
+++ b/src/datavisualization/engine/drawer.cpp
@@ -24,6 +24,7 @@
 #include "q3dcamera.h"
 #include "utils_p.h"
 #include "texturehelper_p.h"
+#include "abstract3drenderer_p.h"
 
 #include <QtGui/QMatrix4x4>
 #include <QtCore/qmath.h>
@@ -349,10 +350,10 @@ void Drawer::drawLabel(const AbstractRenderItem &item, const LabelItem &labelIte
     drawObject(shader, object, labelItem.textureId());
 }
 
-void Drawer::generateSelectionLabelTexture(AbstractRenderItem *item)
+void Drawer::generateSelectionLabelTexture(Abstract3DRenderer *renderer)
 {
-    LabelItem &labelItem = item->selectionLabelItem();
-    generateLabelItem(labelItem, item->selectionLabel());
+    LabelItem &labelItem = renderer->selectionLabelItem();
+    generateLabelItem(labelItem, renderer->selectionLabel());
 }
 
 void Drawer::generateLabelItem(LabelItem &item, const QString &text, int widestLabel)
diff --git a/src/datavisualization/engine/drawer_p.h b/src/datavisualization/engine/drawer_p.h
index 54c8111e..8e98aa3a 100644
--- a/src/datavisualization/engine/drawer_p.h
+++ b/src/datavisualization/engine/drawer_p.h
@@ -43,6 +43,7 @@ class AbstractObjectHelper;
 class SurfaceObject;
 class TextureHelper;
 class Q3DCamera;
+class Abstract3DRenderer;
 
 class Drawer : public QObject, public QOpenGLFunctions
 {
@@ -83,7 +84,7 @@ public:
                    LabelPosition position = LabelOver,
                    Qt::AlignmentFlag alignment = Qt::AlignCenter, bool isSlicing = false);
 
-    void generateSelectionLabelTexture(AbstractRenderItem *item);
+    void generateSelectionLabelTexture(Abstract3DRenderer *item);
     void generateLabelItem(LabelItem &item, const QString &text, int widestLabel = 0);
 
 Q_SIGNALS:
diff --git a/src/datavisualization/engine/scatter3drenderer.cpp b/src/datavisualization/engine/scatter3drenderer.cpp
index 19061b11..de1a769a 100644
--- a/src/datavisualization/engine/scatter3drenderer.cpp
+++ b/src/datavisualization/engine/scatter3drenderer.cpp
@@ -1460,10 +1460,10 @@ void Scatter3DRenderer::drawScene(const GLuint defaultFboHandle)
     } else {
         glDisable(GL_DEPTH_TEST);
         // Draw the selection label
-        LabelItem &labelItem = selectedItem->selectionLabelItem();
+        LabelItem &labelItem = selectionLabelItem();
         if (m_selectedItem != selectedItem || m_updateLabels
                 || !labelItem.textureId() || m_selectionLabelDirty) {
-            QString labelText = selectedItem->selectionLabel();
+            QString labelText = selectionLabel();
             if (labelText.isNull() || m_selectionLabelDirty) {
                 static const QString xTitleTag(QStringLiteral("@xTitle"));
                 static const QString yTitleTag(QStringLiteral("@yTitle"));
@@ -1505,7 +1505,7 @@ void Scatter3DRenderer::drawScene(const GLuint defaultFboHandle)
                 }
                 labelText.replace(seriesNameTag, m_visibleSeriesList[m_selectedItemSeriesIndex].name());
 
-                selectedItem->setSelectionLabel(labelText);
+                setSelectionLabel(labelText);
                 m_selectionLabelDirty = false;
             }
             m_drawer->generateLabelItem(labelItem, labelText);
@@ -1534,6 +1534,7 @@ void Scatter3DRenderer::drawScene(const GLuint defaultFboHandle)
 void Scatter3DRenderer::updateSelectedItem(int index, const QScatter3DSeries *series)
 {
     m_selectionDirty = true;
+    m_selectionLabelDirty = true;
     m_selectedSeries = series;
     m_selectedItemIndex = Scatter3DController::invalidSelectionIndex();
     m_selectedItemTotalIndex = Scatter3DController::invalidSelectionIndex();