From 79d9101394e590064c337653912df6c7f6a1c94e 2012-07-19 12:56:57
From: Michal Klocek <michal.klocek@digia.com>
Date: 2012-07-19 12:56:57
Subject: [PATCH] Fixes rounding issue with labels numbering

---

diff --git a/src/axis/categoriesaxis/chartcategoriesaxisx.cpp b/src/axis/categoriesaxis/chartcategoriesaxisx.cpp
index fdac3de..6b5eba7 100644
--- a/src/axis/categoriesaxis/chartcategoriesaxisx.cpp
+++ b/src/axis/categoriesaxis/chartcategoriesaxisx.cpp
@@ -21,7 +21,8 @@
 #include "chartcategoriesaxisx_p.h"
 #include "chartpresenter_p.h"
 #include "qbarcategoriesaxis_p.h"
-#include <cmath>
+#include <QDebug>
+#include <qmath.h>
 
 static int label_padding = 5;
 
@@ -42,29 +43,47 @@ QVector<qreal> ChartCategoriesAxisX::calculateLayout() const
     Q_ASSERT(m_categoriesAxis->categories().count()>=1);
 
     QVector<qreal> points;
-    points.resize(m_categoriesAxis->categories().count()+1);
+    points.resize(m_categoriesAxis->categories().count()+2);
 
     const qreal delta = m_rect.width()/(m_categoriesAxis->categories().count());
-    const qreal min = m_categoriesAxis->d_ptr->min();
-    const qreal max = m_categoriesAxis->d_ptr->max();
-    qreal start =-min-0.5;
-    if(start<=0) {
-        start = fmod(start * m_rect.width()/(max - min),delta) + delta;
+    qreal offset =-m_min-0.5;
+
+    if(offset<=0) {
+        offset = int(offset * m_rect.width()/(m_max - m_min))%int(delta) + delta;
     }
     else {
-        start = fmod(start * m_rect.width()/(max - min),delta);
+        offset = int(offset * m_rect.width()/(m_max - m_min))%int(delta);
     }
 
-    points[m_categoriesAxis->categories().count()] = m_rect.left() + m_rect.width();
+    points[0] = m_rect.left();
+    points[m_categoriesAxis->categories().count()+1] = m_rect.right();
 
     for (int i = 0; i < m_categoriesAxis->categories().count(); ++i) {
-        qreal x = start + i * delta + m_rect.left();
-        points[i] = x;
+        qreal x = offset + i * delta + m_rect.left();
+        points[i+1] = x;
     }
-
     return points;
 }
 
+QStringList ChartCategoriesAxisX::createCategoryLabels(const QVector<qreal>& layout) const
+{
+    QStringList result;
+    qreal d = (m_max - m_min)/m_rect.width();
+    for (int i = 0;i < layout.count()-1; ++i) {
+        qreal x = qFloor((((layout[i+1] + layout[i])/2-m_rect.left())*d + m_min+0.5));
+        if ((x < m_categoriesAxis->categories().count()) && (x >= 0)) {
+            result << m_categoriesAxis->categories().at(x);
+        }
+        else {
+            // No label for x coordinate
+            result << "";
+        }
+    }
+    result << "";
+    return result;
+}
+
+
 void ChartCategoriesAxisX::updateGeometry()
 {
     const QVector<qreal>& layout = ChartAxis::layout();
@@ -74,9 +93,7 @@ void ChartCategoriesAxisX::updateGeometry()
 
     if(layout.isEmpty()) return;
 
-    QStringList ticksList;
-
-    createCategoryLabels(ticksList,m_min,m_max,m_categoriesAxis->categories());
+    QStringList ticksList = createCategoryLabels(layout);
 
     QList<QGraphicsItem *> lines = m_grid->childItems();
     QList<QGraphicsItem *> labels = m_labels->childItems();
@@ -101,10 +118,10 @@ void ChartCategoriesAxisX::updateGeometry()
         QPointF center = rect.center();
         labelItem->setTransformOriginPoint(center.x(), center.y());
 
-        if(i==layout.size()-1){
-            labelItem->setPos(layout[i-1] + (delta)/2 - center.x(), m_rect.bottom() + label_padding);
+        if(i==0){
+            labelItem->setPos(layout[i+1] - (delta)/2 - center.x(), m_rect.bottom() + label_padding);
         }else{
-            labelItem->setPos(layout[i] - (delta)/2 - center.x(), m_rect.bottom() + label_padding);
+            labelItem->setPos(layout[i] + (delta)/2 - center.x(), m_rect.bottom() + label_padding);
         }
 
         if(labelItem->pos().x()<=width || labelItem->pos().x()+ rect.width()>m_rect.right()) {
diff --git a/src/axis/categoriesaxis/chartcategoriesaxisx_p.h b/src/axis/categoriesaxis/chartcategoriesaxisx_p.h
index 730e5b6..3bed620 100644
--- a/src/axis/categoriesaxis/chartcategoriesaxisx_p.h
+++ b/src/axis/categoriesaxis/chartcategoriesaxisx_p.h
@@ -49,6 +49,8 @@ public:
 protected:
     QVector<qreal> calculateLayout() const;
     void updateGeometry();
+private:
+    QStringList createCategoryLabels(const QVector<qreal>& layout) const;
 Q_SLOTS
     void handleAxisUpdated();
 
diff --git a/src/axis/categoriesaxis/chartcategoriesaxisy.cpp b/src/axis/categoriesaxis/chartcategoriesaxisy.cpp
index 28e9f67..2c009fa 100644
--- a/src/axis/categoriesaxis/chartcategoriesaxisy.cpp
+++ b/src/axis/categoriesaxis/chartcategoriesaxisy.cpp
@@ -21,8 +21,7 @@
 #include "chartcategoriesaxisy_p.h"
 #include "chartpresenter_p.h"
 #include "qbarcategoriesaxis_p.h"
-#include <QDebug>
-#include <cmath>
+#include <qmath.h>
 
 static int label_padding = 5;
 
@@ -42,32 +41,46 @@ QVector<qreal> ChartCategoriesAxisY::calculateLayout() const
     Q_ASSERT(m_categoriesAxis->categories().count()>=1);
 
     QVector<qreal> points;
-    points.resize(m_categoriesAxis->categories().count()+1);
+    points.resize(m_categoriesAxis->categories().count()+2);
 
-    qreal delta = m_rect.height()/(m_categoriesAxis->categories().count());
-
-    const qreal min = m_categoriesAxis->d_ptr->min();
-    const qreal max = m_categoriesAxis->d_ptr->max();
-
-    qreal start =-min-0.5;
+    const qreal delta = m_rect.height()/(m_categoriesAxis->categories().count());
+    qreal offset = - m_min - 0.5;
 
-    if(start<=0) {
-        start = fmod(start * m_rect.height()/(max - min),delta) + delta;
+    if(offset<=0) {
+        offset = int(offset * m_rect.height()/(m_max - m_min))%int(delta) + delta;
     }
     else {
-        start = fmod(start * m_rect.height()/(max - min),delta);
+        offset = int(offset * m_rect.height()/(m_max - m_min))%int(delta);
     }
 
-    points[m_categoriesAxis->categories().count()] = m_rect.top();
+    points[0] = m_rect.bottom();
+    points[m_categoriesAxis->categories().count()+1] = m_rect.top();
 
     for (int i = 0; i < m_categoriesAxis->categories().count(); ++i) {
-        int y = m_rect.bottom() - i * delta - start;
-        points[i] = y;
+        int y = m_rect.bottom() - i * delta - offset;
+        points[i+1] = y;
     }
-
     return points;
 }
 
+QStringList ChartCategoriesAxisY::createCategoryLabels(const QVector<qreal>& layout) const
+{
+    QStringList result;
+    qreal d = (m_max - m_min)/m_rect.height();
+    for (int i = 0;i < layout.count()-1; ++i) {
+        qreal x = qFloor(((m_rect.height()- (layout[i+1] + layout[i])/2 + m_rect.top())*d + m_min+0.5));
+        if ((x < m_categoriesAxis->categories().count()) && (x >= 0)) {
+            result << m_categoriesAxis->categories().at(x);
+        }
+        else {
+            // No label for x coordinate
+            result << "";
+        }
+    }
+    result << "";
+    return result;
+}
+
 void ChartCategoriesAxisY::updateGeometry()
 {
     const QVector<qreal>& layout = ChartAxis::layout();
@@ -77,9 +90,7 @@ void ChartCategoriesAxisY::updateGeometry()
 
     if(layout.isEmpty()) return;
 
-    QStringList ticksList;
-
-    createCategoryLabels(ticksList,m_min,m_max,m_categoriesAxis->categories());
+    QStringList ticksList = createCategoryLabels(layout);
 
     QList<QGraphicsItem *> lines = m_grid->childItems();
     QList<QGraphicsItem *> labels = m_labels->childItems();
@@ -104,11 +115,11 @@ void ChartCategoriesAxisY::updateGeometry()
         QPointF center = rect.center();
         labelItem->setTransformOriginPoint(center.x(), center.y());
 
-        if(i==layout.size()-1) {
-            labelItem->setPos(m_rect.left() - rect.width() - label_padding ,layout[i-1] - (delta)/2 - center.y());
+        if(i==0) {
+           labelItem->setPos(m_rect.left() - rect.width() - label_padding ,layout[i+1] + (delta)/2 - center.y());
         }
         else {
-            labelItem->setPos(m_rect.left() - rect.width() - label_padding ,layout[i] + (delta)/2 - center.y());
+            labelItem->setPos(m_rect.left() - rect.width() - label_padding ,layout[i] - (delta)/2 - center.y());
         }
 
         if(labelItem->pos().y()+rect.height()>= height || labelItem->pos().y() < m_rect.top()) {
@@ -137,7 +148,10 @@ void ChartCategoriesAxisY::handleAxisUpdated()
     if(m_categoriesAxis->categories()!=m_categories)
     {
         m_categories=m_categoriesAxis->categories();
-        if(ChartAxis::layout().count()==m_categories.size()+1) updateGeometry();
+        if(ChartAxis::layout().count()==m_categories.size()+1) {
+
+            updateGeometry();
+        }
     }
     ChartAxis::handleAxisUpdated();
 }
diff --git a/src/axis/categoriesaxis/chartcategoriesaxisy_p.h b/src/axis/categoriesaxis/chartcategoriesaxisy_p.h
index ffe1fa9..899006b 100644
--- a/src/axis/categoriesaxis/chartcategoriesaxisy_p.h
+++ b/src/axis/categoriesaxis/chartcategoriesaxisy_p.h
@@ -49,10 +49,13 @@ public:
 protected:
     QVector<qreal> calculateLayout() const;
     void updateGeometry();
+private:
+    QStringList createCategoryLabels(const QVector<qreal>& layout) const;
 Q_SLOTS
         void handleAxisUpdated();
 private:
     QStringList m_categories;
+    QVector<int> m_labelIndex;
     QBarCategoriesAxis *m_categoriesAxis;
 };
 
diff --git a/src/axis/chartaxis.cpp b/src/axis/chartaxis.cpp
index 809c346..005b903 100644
--- a/src/axis/chartaxis.cpp
+++ b/src/axis/chartaxis.cpp
@@ -24,8 +24,6 @@
 #include "chartpresenter_p.h"
 #include "chartanimator_p.h"
 #include "domain_p.h"
-#include <QPainter>
-#include <QDebug>
 #include <qmath.h>
 #include <QDateTime>
 
@@ -362,7 +360,7 @@ void ChartAxis::createNumberLabels(QStringList &labels,qreal min, qreal max, int
     Q_ASSERT(max>min);
     Q_ASSERT(ticks>1);
 
-    int n = qMax(int(-floor(log10((max-min)/(ticks-1)))),0);
+    int n = qMax(int(-qFloor(log10((max-min)/(ticks-1)))),0);
     n++;
     for (int i=0; i< ticks; i++) {
         qreal value = min + (i * (max - min)/ (ticks-1));
@@ -370,27 +368,6 @@ void ChartAxis::createNumberLabels(QStringList &labels,qreal min, qreal max, int
     }
 }
 
-void ChartAxis::createCategoryLabels(QStringList &labels,qreal min, qreal max,const QStringList &categories) const
-{
-    Q_ASSERT(max>min);
-    Q_UNUSED(max);
-
-    int x = qFloor(min+0.5);
-    int count = 0;
-
-    // Try to find category for x coordinate
-    while (count < categories.count()+1) {
-        if ((x < categories.count()) && (x >= 0)) {
-            labels << categories.at(x);
-        } else {
-            // No label for x coordinate
-            labels << "";
-        }
-        x++;
-        count++;
-    }
-}
-
 #include "moc_chartaxis_p.cpp"
 
 QTCOMMERCIALCHART_END_NAMESPACE
diff --git a/src/axis/chartaxis_p.h b/src/axis/chartaxis_p.h
index eb44c6c..ef92262 100644
--- a/src/axis/chartaxis_p.h
+++ b/src/axis/chartaxis_p.h
@@ -92,7 +92,6 @@ protected:
     virtual void updateGeometry() = 0;
     virtual QVector<qreal> calculateLayout() const = 0;
     void createNumberLabels(QStringList &labels,qreal min, qreal max,int ticks) const;
-    void createCategoryLabels(QStringList &labels,qreal min, qreal max,const QStringList &categories) const;
 
 public Q_SLOTS:
     virtual void handleAxisUpdated();