Make background margin configurable

Added margin as abstract graph property.
If the margin is narrow, the positions of theedge labels of the axes
are adjusted to avoid overlap with edge labels on other axes.

Task-number: QTRD-3204
Change-Id: I7fa5a04c8f2091519d99689ef2f6cbcf799fb15e
Reviewed-by: Mika Salmela <mika.salmela@digia.com>
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>

1 files changed, 65 insertions, 7 deletions

diff --git a/src/datavisualization/engine/surface3drenderer.cpp b/src/datavisualization/engine/surface3drenderer.cpp
index 3d39a71d..02add48f 100644
--- a/src/datavisualization/engine/surface3drenderer.cpp
+++ b/src/datavisualization/engine/surface3drenderer.cpp
@@ -53,9 +53,6 @@ Surface3DRenderer::Surface3DRenderer(Surface3DController *controller)
       m_scaleX(0.0f),
       m_scaleY(0.0f),
       m_scaleZ(0.0f),
-      m_scaleXWithBackground(0.0f),
-      m_scaleYWithBackground(0.0f),
-      m_scaleZWithBackground(0.0f),
       m_depthModelTexture(0),
       m_depthFrameBuffer(0),
       m_selectionFrameBuffer(0),
@@ -2089,6 +2086,23 @@ void Surface3DRenderer::drawLabels(bool drawSelection, const Q3DCamera *activeCa
             } else {
                 labelTrans.setZ(m_axisCacheZ.labelPosition(label));
             }
+            if (label == 0 || label == (labelCount - 1)) {
+                // If the margin is small, adjust the position of the edge labels to avoid overlapping
+                // with labels of the other axes.
+                float scaleFactor = m_drawer->scaledFontSize() / axisLabelItem.size().height();
+                float labelOverlap = qAbs(labelTrans.z())
+                        + (scaleFactor * axisLabelItem.size().height() / 2.0f)
+                        - m_scaleZWithBackground + labelMargin;
+                // No need to adjust quite as much on the front edges
+                if (label != startIndex)
+                    labelOverlap /= 2.0f;
+                if (labelOverlap > 0.0f) {
+                    if (label == 0)
+                        labelTrans.setZ(labelTrans.z() - labelOverlap);
+                    else
+                        labelTrans.setZ(labelTrans.z() + labelOverlap);
+                }
+            }
             m_dummyRenderItem.setTranslation(labelTrans);
 
             if (drawSelection) {
@@ -2264,8 +2278,25 @@ void Surface3DRenderer::drawLabels(bool drawSelection, const Q3DCamera *activeCa
             } else {
                 labelTrans.setX(m_axisCacheX.labelPosition(label));
             }
-            m_dummyRenderItem.setTranslation(labelTrans);
             const LabelItem &axisLabelItem = *m_axisCacheX.labelItems().at(label);
+            if (label == 0 || label == (labelCount - 1)) {
+                // If the margin is small, adjust the position of the edge labels to avoid overlapping
+                // with labels of the other axes.
+                float scaleFactor = m_drawer->scaledFontSize() / axisLabelItem.size().height();
+                float labelOverlap = qAbs(labelTrans.x())
+                        + (scaleFactor * axisLabelItem.size().height() / 2.0f)
+                        - m_scaleXWithBackground + labelMargin;
+                // No need to adjust quite as much on the front edges
+                if (label != startIndex)
+                    labelOverlap /= 2.0f;
+                if (labelOverlap > 0.0f) {
+                    if (label == 0)
+                        labelTrans.setX(labelTrans.x() + labelOverlap);
+                    else
+                        labelTrans.setX(labelTrans.x() - labelOverlap);
+                }
+            }
+            m_dummyRenderItem.setTranslation(labelTrans);
 
             if (drawSelection) {
                 QVector4D labelColor = QVector4D(0.0f, label / 255.0f, 0.0f,
@@ -2368,7 +2399,7 @@ void Surface3DRenderer::drawLabels(bool drawSelection, const Q3DCamera *activeCa
         float offsetValue = 0.0f;
         for (int label = startIndex; label != endIndex; label = label + indexStep) {
             const LabelItem &axisLabelItem = *m_axisCacheY.labelItems().at(label);
-            const float labelYTrans = m_axisCacheY.labelPosition(label);
+            float labelYTrans = m_axisCacheY.labelPosition(label);
 
             glPolygonOffset(offsetValue++ / -10.0f, 1.0f);
 
@@ -2378,6 +2409,21 @@ void Surface3DRenderer::drawLabels(bool drawSelection, const Q3DCamera *activeCa
                 shader->setUniformValue(shader->color(), labelColor);
             }
 
+            if (label == startIndex) {
+                // If the margin is small, adjust the position of the edge label to avoid
+                // overlapping with labels of the other axes.
+                float scaleFactor = m_drawer->scaledFontSize() / axisLabelItem.size().height();
+                float labelOverlap = qAbs(labelYTrans)
+                        + (scaleFactor * axisLabelItem.size().height() / 2.0f)
+                        - m_scaleYWithBackground + labelMargin;
+                if (labelOverlap > 0.0f) {
+                    if (label == 0)
+                        labelYTrans += labelOverlap;
+                    else
+                        labelYTrans -= labelOverlap;
+                }
+            }
+
             // Back wall
             labelTransBack.setY(labelYTrans);
             m_dummyRenderItem.setTranslation(labelTransBack);
@@ -2514,9 +2560,15 @@ void Surface3DRenderer::idToRGBA(uint id, uchar *r, uchar *g, uchar *b, uchar *a
 
 void Surface3DRenderer::calculateSceneScalingFactors()
 {
-    // Margin for background (0.10 make it 10% larger to avoid
+    // Margin for background (the default 0.10 makes it 10% larger to avoid
     // selection ball being drawn inside background)
-    m_hBackgroundMargin = 0.1f;
+    if (m_requestedMargin < 0.0f) {
+        m_hBackgroundMargin = 0.1f;
+        m_vBackgroundMargin = 0.1f;
+    } else {
+        m_hBackgroundMargin = m_requestedMargin;
+        m_vBackgroundMargin = m_requestedMargin;
+    }
     if (m_polarGraph) {
         float polarMargin = calculatePolarBackgroundMargin();
         m_hBackgroundMargin = qMax(m_hBackgroundMargin, polarMargin);
@@ -3032,4 +3084,10 @@ void Surface3DRenderer::updateAxisTitleVisibility(QAbstract3DAxis::AxisOrientati
         calculateSceneScalingFactors();
 }
 
+void Surface3DRenderer::updateMargin(float margin)
+{
+    Abstract3DRenderer::updateMargin(margin);
+    calculateSceneScalingFactors();
+}
+
 QT_END_NAMESPACE_DATAVISUALIZATION