Label "skewing" fixed

Task-number: QTRD-2322

Change-Id: Ie4bb95dc4f62bad1fef605461452168ea260fa26
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>
Reviewed-by: Mika Salmela <mika.salmela@digia.com>

8 files changed, 43 insertions, 44 deletions

diff --git a/src/datavisualization/engine/axisrendercache.cpp b/src/datavisualization/engine/axisrendercache.cpp
index c525c777..55ac0765 100644
--- a/src/datavisualization/engine/axisrendercache.cpp
+++ b/src/datavisualization/engine/axisrendercache.cpp
@@ -173,7 +173,7 @@ int AxisRenderCache::maxLabelWidth(const QStringList &labels) const
 {
     int labelWidth = 0;
     QFont labelFont = m_font;
-    labelFont.setPointSize(50);
+    labelFont.setPointSize(textureFontSize);
     QFontMetrics labelFM(labelFont);
     for (int i = 0; i < labels.size(); i++) {
         int newWidth = labelFM.width(labels.at(i));
diff --git a/src/datavisualization/engine/bars3drenderer.cpp b/src/datavisualization/engine/bars3drenderer.cpp
index bf57f21f..b2f3bd41 100644
--- a/src/datavisualization/engine/bars3drenderer.cpp
+++ b/src/datavisualization/engine/bars3drenderer.cpp
@@ -216,7 +216,7 @@ void Bars3DRenderer::updateScene(Q3DScene *scene)
     scene->setUnderSideCameraEnabled(m_hasNegativeValues);
     if (m_hasHeightAdjustmentChanged) {
         // Set initial camera position. Also update if height adjustment has changed.
-        scene->activeCamera()->setBaseOrientation(QVector3D(0.0f, 0.0f, 6.0f + zComp),
+        scene->activeCamera()->setBaseOrientation(QVector3D(0.0f, 0.0f, cameraDistance + zComp),
                                                   QVector3D(0.0f, -m_yAdjustment, zComp),
                                                   QVector3D(0.0f, 1.0f, 0.0f));
         m_hasHeightAdjustmentChanged = false;
@@ -363,10 +363,8 @@ void Bars3DRenderer::drawSlicedScene(const LabelItem &xLabel,
     glDisable(GL_DEPTH_TEST);
     glEnable(GL_TEXTURE_2D);
     glCullFace(GL_BACK);
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone) {
-        glEnable(GL_BLEND);
-        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-    }
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
     // Draw labels for axes
     BarRenderItem *dummyItem(0);
@@ -439,8 +437,7 @@ void Bars3DRenderer::drawSlicedScene(const LabelItem &xLabel,
     }
 
     glDisable(GL_TEXTURE_2D);
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone)
-        glDisable(GL_BLEND);
+    glDisable(GL_BLEND);
     glEnable(GL_DEPTH_TEST);
 
     // Release label shader
@@ -1233,10 +1230,8 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
     m_labelShader->bind();
 
     glEnable(GL_TEXTURE_2D);
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone) {
-        glEnable(GL_BLEND);
-        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-    }
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
     // Calculate the positions for row and column labels and store them
     for (int row = 0; row != m_cachedRowCount; row++) {
@@ -1472,8 +1467,7 @@ void Bars3DRenderer::drawScene(GLuint defaultFboHandle)
     }
 
     glDisable(GL_TEXTURE_2D);
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone)
-        glDisable(GL_BLEND);
+    glDisable(GL_BLEND);
 
     // Release label shader
     m_labelShader->release();
diff --git a/src/datavisualization/engine/drawer.cpp b/src/datavisualization/engine/drawer.cpp
index 7fcf581f..307dd63e 100644
--- a/src/datavisualization/engine/drawer.cpp
+++ b/src/datavisualization/engine/drawer.cpp
@@ -309,10 +309,11 @@ void Drawer::drawLabel(const AbstractRenderItem &item, const LabelItem &labelIte
     modelMatrix.rotate(rotation.x(), 1.0f, 0.0f, 0.0f);
 
     if (useDepth && !rotateAlong) {
+        qreal yComp = qreal(qRadiansToDegrees(qTan(positionComp.y() / cameraDistance)));
         // Apply negative camera rotations to keep labels facing camera
         QPointF camRotations = camera->rotations();
         modelMatrix.rotate(-camRotations.x(), 0.0f, 1.0f, 0.0f);
-        modelMatrix.rotate(-camRotations.y(), 1.0f, 0.0f, 0.0f);
+        modelMatrix.rotate(-camRotations.y() - yComp, 1.0f, 0.0f, 0.0f);
     }
 
     // Scale label based on text size
diff --git a/src/datavisualization/engine/scatter3drenderer.cpp b/src/datavisualization/engine/scatter3drenderer.cpp
index 38044bbe..5c643bb2 100644
--- a/src/datavisualization/engine/scatter3drenderer.cpp
+++ b/src/datavisualization/engine/scatter3drenderer.cpp
@@ -170,7 +170,7 @@ void Scatter3DRenderer::updateScene(Q3DScene *scene)
 
     if (m_hasHeightAdjustmentChanged) {
         // Set initial m_cachedScene->activeCamera() position. Also update if height adjustment has changed.
-        scene->activeCamera()->setBaseOrientation(QVector3D(0.0f, 0.0f, 6.0f + zComp),
+        scene->activeCamera()->setBaseOrientation(QVector3D(0.0f, 0.0f, cameraDistance + zComp),
                                                   QVector3D(0.0f, 0.0f, zComp),
                                                   QVector3D(0.0f, 1.0f, 0.0f));
         m_hasHeightAdjustmentChanged = false;
@@ -1071,10 +1071,8 @@ void Scatter3DRenderer::drawScene(const GLuint defaultFboHandle)
     m_labelShader->bind();
 
     glEnable(GL_TEXTURE_2D);
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone) {
-        glEnable(GL_BLEND);
-        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-    }
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
     // Z Labels
     if (m_axisCacheZ.segmentCount() > 0) {
@@ -1333,7 +1331,8 @@ void Scatter3DRenderer::drawScene(const GLuint defaultFboHandle)
                             QVector3D(0.0f, 0.0f, zComp),
                             QVector3D(0.0f, 0.0f, 0.0f), 0,
                             m_cachedSelectionMode, m_labelShader,
-                            m_labelObj, m_cachedScene->activeCamera(), true, false, Drawer::LabelMid);
+                            m_labelObj, m_cachedScene->activeCamera(), true, false,
+                            Drawer::LabelMid);
 
         // Reset label update flag; they should have been updated when we get here
         m_updateLabels = false;
@@ -1341,8 +1340,7 @@ void Scatter3DRenderer::drawScene(const GLuint defaultFboHandle)
     }
 
     glDisable(GL_TEXTURE_2D);
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone)
-        glDisable(GL_BLEND);
+    glDisable(GL_BLEND);
 
     // Release label shader
     m_labelShader->release();
diff --git a/src/datavisualization/engine/surface3drenderer.cpp b/src/datavisualization/engine/surface3drenderer.cpp
index 656d469a..9fea6ddb 100644
--- a/src/datavisualization/engine/surface3drenderer.cpp
+++ b/src/datavisualization/engine/surface3drenderer.cpp
@@ -281,7 +281,7 @@ void Surface3DRenderer::updateScene(Q3DScene *scene)
     // Set initial camera position
     // X must be 0 for rotation to work - we can use "setCameraRotation" for setting it later
     if (m_hasHeightAdjustmentChanged) {
-        scene->activeCamera()->setBaseOrientation(QVector3D(0.0f, 0.0f, 6.0f + zComp),
+        scene->activeCamera()->setBaseOrientation(QVector3D(0.0f, 0.0f, cameraDistance + zComp),
                                                   QVector3D(0.0f, 0.0f, zComp),
                                                   QVector3D(0.0f, 1.0f, 0.0f));
         // For now this is used just to make things once. Proper use will come
@@ -1006,10 +1006,8 @@ void Surface3DRenderer::drawScene(GLuint defaultFboHandle)
     // Draw axis labels
     m_labelShader->bind();
 
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone) {
-        glEnable(GL_BLEND);
-        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-    }
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
     // Z Labels
     QVector3D positionZComp(0.0f, 0.0f, zComp);
@@ -1179,8 +1177,7 @@ void Surface3DRenderer::drawScene(GLuint defaultFboHandle)
 
     glDisable(GL_TEXTURE_2D);
 
-    if (m_cachedLabelTransparency > QDataVis::TransparencyNone)
-        glDisable(GL_BLEND);
+    glDisable(GL_BLEND);
 
     // Release label shader
     m_labelShader->release();
diff --git a/src/datavisualization/global/datavisualizationglobal_p.h b/src/datavisualization/global/datavisualizationglobal_p.h
index 29fcc532..4da1023c 100644
--- a/src/datavisualization/global/datavisualizationglobal_p.h
+++ b/src/datavisualization/global/datavisualizationglobal_p.h
@@ -40,6 +40,10 @@ QT_DATAVISUALIZATION_BEGIN_NAMESPACE
 // Constants used in several files
 // Compensation for z position; move all objects to positive z, as shader can't handle negative values correctly
 const GLfloat zComp = 10.0f;
+// Distance from camera to origin
+const GLfloat cameraDistance = 6.0f;
+// Size of font to be used in label texture rendering. Doesn't affect the actual font size.
+const int textureFontSize = 50;
 // Default light position. To have shadows working correctly, light should be as far as camera, or a bit further
 // y position is added to the minimum height (or can be thought to be that much above or below the camera)
 const QVector3D defaultLightPos = QVector3D(0.0f, 0.5f, zComp);
diff --git a/src/datavisualization/utils/utils.cpp b/src/datavisualization/utils/utils.cpp
index eaefad97..4cda5fad 100644
--- a/src/datavisualization/utils/utils.cpp
+++ b/src/datavisualization/utils/utils.cpp
@@ -52,7 +52,7 @@ QImage Utils::printTextToImage(const QFont &font, const QString &text, const QCo
     GLuint paddingHeight = 15;
     // Calculate text dimensions
     QFont valueFont = font;
-    valueFont.setPointSize(50);
+    valueFont.setPointSize(textureFontSize);
     QFontMetrics valueFM(valueFont);
     int valueStrWidth = valueFM.width(text);
     if (maxLabelWidth && QDataVis::TransparencyNoBackground != transparency)
@@ -88,9 +88,9 @@ QImage Utils::printTextToImage(const QFont &font, const QString &text, const QCo
     // Paint text
     painter.setRenderHint(QPainter::Antialiasing, true);
     painter.setCompositionMode(QPainter::CompositionMode_Source);
+    painter.setFont(valueFont);
     switch (transparency) {
     case QDataVis::TransparencyNoBackground: {
-        painter.setFont(valueFont);
         painter.setPen(txtColor);
 #if defined(Q_OS_ANDROID)
         painter.drawText((labelSize.width() - valueStrWidth) / 2.0f,
@@ -108,12 +108,14 @@ QImage Utils::printTextToImage(const QFont &font, const QString &text, const QCo
     }
     case QDataVis::TransparencyFromTheme: {
         painter.setBrush(QBrush(bgrColor));
-        if (borders)
+        if (borders) {
             painter.setPen(QPen(QBrush(txtColor), 5, Qt::SolidLine, Qt::SquareCap, Qt::RoundJoin));
-        else
+            painter.drawRoundedRect(5, 5, labelSize.width() - 10, labelSize.height() - 10,
+                                    10.0, 10.0);
+        } else {
             painter.setPen(bgrColor);
-        painter.drawRoundedRect(0, 0, labelSize.width(), labelSize.height(), 10.0, 10.0f);
-        painter.setFont(valueFont);
+            painter.drawRoundedRect(0, 0, labelSize.width(), labelSize.height(), 10.0, 10.0);
+        }
         painter.setPen(txtColor);
         painter.drawText((labelSize.width() - valueStrWidth) / 2.0f,
                          (labelSize.height() - valueStrHeight) / 2.0f,
@@ -123,13 +125,16 @@ QImage Utils::printTextToImage(const QFont &font, const QString &text, const QCo
         break;
     }
     case QDataVis::TransparencyNone: {
-        painter.setBrush(QBrush(bgrColor));
-        if (borders)
-            painter.setPen(QPen(QBrush(txtColor), 7.5));
-        else
-            painter.setPen(bgrColor);
-        painter.drawRect(0, 0, labelSize.width(), labelSize.height());
-        painter.setFont(valueFont);
+        QColor labelColor = QColor(bgrColor);
+        labelColor.setAlphaF(1.0);
+        painter.setBrush(QBrush(labelColor));
+        if (borders) {
+            painter.setPen(QPen(QBrush(txtColor), 7.5, Qt::SolidLine, Qt::SquareCap, Qt::MiterJoin));
+            painter.drawRect(7.5, 7.5, labelSize.width() - 15, labelSize.height() - 15);
+        } else {
+            painter.setPen(labelColor);
+            painter.drawRect(0, 0, labelSize.width(), labelSize.height());
+        }
         painter.setPen(txtColor);
         painter.drawText((labelSize.width() - valueStrWidth) / 2.0f,
                          (labelSize.height() - valueStrHeight) / 2.0f,
diff --git a/tests/barstest/chart.cpp b/tests/barstest/chart.cpp
index cfc072de..578ac258 100644
--- a/tests/barstest/chart.cpp
+++ b/tests/barstest/chart.cpp
@@ -468,7 +468,7 @@ void ChartModifier::changeTransparency()
     m_chart->setLabelTransparency((QDataVis::LabelTransparency)transparency);
 
     if (++transparency > QDataVis::TransparencyNoBackground)
-        transparency = QDataVis::TransparencyFromTheme;
+        transparency = QDataVis::TransparencyNone;
 }
 
 void ChartModifier::changeSelectionMode()