Fix shades for log and category axes.

Partial spans at the chart edges are now shaded properly.

Task-number: QTRD-1940
Change-Id: Ibe03a2b9638ccb16d9c8c9bc7f2a0f924a7115d4
Reviewed-by: Titta Heikkala <titta.heikkala@theqtcompany.com>

3 files changed, 54 insertions, 20 deletions

diff --git a/src/charts/axis/cartesianchartaxis.cpp b/src/charts/axis/cartesianchartaxis.cpp
index 399662ec..ecdb0e58 100644
--- a/src/charts/axis/cartesianchartaxis.cpp
+++ b/src/charts/axis/cartesianchartaxis.cpp
@@ -56,6 +56,10 @@ void CartesianChartAxis::createItems(int count)
             QGraphicsLineItem *item = new QGraphicsLineItem(this);
             item->setPen(axis()->gridLinePen());
             gridGroup()->addToGroup(item);
+            QGraphicsRectItem *shades = new QGraphicsRectItem(this);
+            shades->setPen(axis()->shadesPen());
+            shades->setBrush(axis()->shadesBrush());
+            shadeGroup()->addToGroup(shades);
         }
     }
 
@@ -78,14 +82,13 @@ void CartesianChartAxis::createItems(int count)
         gridGroup()->addToGroup(grid);
         labelGroup()->addToGroup(label);
 
-        if ((gridItems().size()) % 2 && gridItems().size() > 2) {
-            QGraphicsRectItem* shades = new QGraphicsRectItem(this);
+        if (gridItems().size() == 1 || (((gridItems().size() + 1) % 2) && gridItems().size() > 0)) {
+            QGraphicsRectItem *shades = new QGraphicsRectItem(this);
             shades->setPen(axis()->shadesPen());
             shades->setBrush(axis()->shadesBrush());
             shadeGroup()->addToGroup(shades);
         }
     }
-
 }
 
 void CartesianChartAxis::deleteItems(int count)
@@ -96,7 +99,7 @@ void CartesianChartAxis::deleteItems(int count)
     QList<QGraphicsItem *> axis = arrowItems();
 
     for (int i = 0; i < count; ++i) {
-        if (lines.size() % 2 && lines.size() > 1)
+        if (lines.size() == 1 || (((lines.size() + 1) % 2) && lines.size() > 0))
             delete(shades.takeLast());
         delete(lines.takeLast());
         delete(labels.takeLast());
diff --git a/src/charts/axis/horizontalaxis.cpp b/src/charts/axis/horizontalaxis.cpp
index 8e3bb975..c727d545 100644
--- a/src/charts/axis/horizontalaxis.cpp
+++ b/src/charts/axis/horizontalaxis.cpp
@@ -161,15 +161,30 @@ void HorizontalAxis::updateGeometry()
         }
 
         //shades
-        if ((i + 1) % 2 && i > 1) {
-            QGraphicsRectItem *rectItem = static_cast<QGraphicsRectItem *>(shades.at(i / 2 - 1));
-            qreal leftBound = qMax(layout[i - 1], gridRect.left());
-            qreal rightBound = qMin(layout[i], gridRect.right());
-            rectItem->setRect(leftBound, gridRect.top(), rightBound - leftBound, gridRect.height());
-            if (rectItem->rect().width() <= 0.0)
-                rectItem->setVisible(false);
+        QGraphicsRectItem *shadeItem = 0;
+        if (i == 0)
+            shadeItem = static_cast<QGraphicsRectItem *>(shades.at(0));
+        else if (i % 2)
+            shadeItem = static_cast<QGraphicsRectItem *>(shades.at((i / 2) + 1));
+        if (shadeItem) {
+            qreal leftBound;
+            qreal rightBound;
+            if (i == 0) {
+                leftBound = gridRect.left();
+                rightBound = layout[0];
+            } else {
+                leftBound = layout[i];
+                if (i == layout.size() - 1)
+                    rightBound = gridRect.right();
+                else
+                    rightBound = qMin(layout[i + 1], gridRect.right());
+            }
+            shadeItem->setRect(leftBound, gridRect.top(), rightBound - leftBound,
+                               gridRect.height());
+            if (shadeItem->rect().width() <= 0.0)
+                shadeItem->setVisible(false);
             else
-                rectItem->setVisible(true);
+                shadeItem->setVisible(true);
         }
 
         // check if the grid line and the axis tick should be shown
diff --git a/src/charts/axis/verticalaxis.cpp b/src/charts/axis/verticalaxis.cpp
index 484ca1f8..445ab254 100644
--- a/src/charts/axis/verticalaxis.cpp
+++ b/src/charts/axis/verticalaxis.cpp
@@ -165,15 +165,31 @@ void VerticalAxis::updateGeometry()
         }
 
         //shades
-        if ((i + 1) % 2 && i > 1) {
-            QGraphicsRectItem *rectItem = static_cast<QGraphicsRectItem *>(shades.at(i / 2 - 1));
-            qreal lowerBound = qMin(layout[i - 1], gridRect.bottom());
-            qreal upperBound = qMax(layout[i], gridRect.top());
-            rectItem->setRect(gridRect.left(), upperBound, gridRect.width(), lowerBound - upperBound);
-            if (rectItem->rect().height() <= 0.0)
-                rectItem->setVisible(false);
+        QGraphicsRectItem *shadeItem = 0;
+        if (i == 0)
+            shadeItem = static_cast<QGraphicsRectItem *>(shades.at(0));
+        else if (i % 2)
+            shadeItem = static_cast<QGraphicsRectItem *>(shades.at((i / 2) + 1));
+        if (shadeItem) {
+            qreal lowerBound;
+            qreal upperBound;
+            if (i == 0) {
+                lowerBound = gridRect.bottom();
+                upperBound = layout[0];
+            } else {
+                lowerBound = layout[i];
+                if (i == layout.size() - 1)
+                    upperBound = gridRect.top();
+                else
+                    upperBound = qMax(layout[i + 1], gridRect.top());
+
+            }
+            shadeItem->setRect(gridRect.left(), upperBound, gridRect.width(),
+                               lowerBound - upperBound);
+            if (shadeItem->rect().height() <= 0.0)
+                shadeItem->setVisible(false);
             else
-                rectItem->setVisible(true);
+                shadeItem->setVisible(true);
         }
 
         // check if the grid line and the axis tick should be shown