Add support for reversed axis when useOpenGL is true

Change-Id: If8b6690585c767b65eaa4a43e179c86183903637
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@theqtcompany.com>

8 files changed, 85 insertions, 23 deletions

diff --git a/src/charts/chartdataset.cpp b/src/charts/chartdataset.cpp
index 33857b0d..cbc4dfbd 100644
--- a/src/charts/chartdataset.cpp
+++ b/src/charts/chartdataset.cpp
@@ -280,7 +280,7 @@ bool ChartDataSet::attachAxis(QAbstractSeries *series,QAbstractAxis *axis)
 
     series->d_ptr->initializeAxes();
     axis->d_ptr->initializeDomain(domain);
-
+    connect(axis, &QAbstractAxis::reverseChanged, this, &ChartDataSet::reverseChanged);
     foreach (AbstractDomain *blockedDomain, blockedDomains)
         blockedDomain->blockRangeSignals(false);
 
@@ -319,7 +319,7 @@ bool ChartDataSet::detachAxis(QAbstractSeries* series,QAbstractAxis *axis)
     domain->detachAxis(axis);
     series->d_ptr->m_axes.removeAll(axis);
     axis->d_ptr->m_series.removeAll(series);
-
+    disconnect(axis, &QAbstractAxis::reverseChanged, this, &ChartDataSet::reverseChanged);
     return true;
 }
 
@@ -645,6 +645,13 @@ AbstractDomain* ChartDataSet::createDomain(AbstractDomain::DomainType type)
     }
 }
 
+void ChartDataSet::reverseChanged()
+{
+    QAbstractAxis *axis = qobject_cast<QAbstractAxis *>(sender());
+    if (axis)
+        m_glXYSeriesDataManager->handleAxisReverseChanged(axis->d_ptr->m_series);
+}
+
 #include "moc_chartdataset_p.cpp"
 
 QT_CHARTS_END_NAMESPACE
diff --git a/src/charts/chartdataset_p.h b/src/charts/chartdataset_p.h
index 85823c4d..bc2917bc 100644
--- a/src/charts/chartdataset_p.h
+++ b/src/charts/chartdataset_p.h
@@ -86,7 +86,8 @@ Q_SIGNALS:
     void axisRemoved(QAbstractAxis* axis);
     void seriesAdded(QAbstractSeries* series);
     void seriesRemoved(QAbstractSeries* series);
-
+public Q_SLOTS:
+    void reverseChanged();
 private:
     void createAxes(QAbstractAxis::AxisTypes type, Qt::Orientation orientation);
     QAbstractAxis *createAxis(QAbstractAxis::AxisType type, Qt::Orientation orientation);
diff --git a/src/charts/glwidget.cpp b/src/charts/glwidget.cpp
index 5ea41f74..c0070dcd 100644
--- a/src/charts/glwidget.cpp
+++ b/src/charts/glwidget.cpp
@@ -109,9 +109,10 @@ static const char *vertexSource =
         "uniform highp vec2 min;\n"
         "uniform highp vec2 delta;\n"
         "uniform highp float pointSize;\n"
+        "uniform highp mat4 matrix;\n"
         "void main() {\n"
         "  vec2 normalPoint = vec2(-1, -1) + ((points - min) / delta);\n"
-        "  gl_Position = vec4(normalPoint, 0, 1);\n"
+        "  gl_Position = matrix * vec4(normalPoint, 0, 1);\n"
         "  gl_PointSize = pointSize;\n"
         "}";
 static const char *fragmentSource =
@@ -138,6 +139,7 @@ void GLWidget::initializeGL()
     m_minUniformLoc = m_program->uniformLocation("min");
     m_deltaUniformLoc = m_program->uniformLocation("delta");
     m_pointSizeUniformLoc = m_program->uniformLocation("pointSize");
+    m_matrixUniformLoc = m_program->uniformLocation("matrix");
 
 
     // Create a vertex array object. In OpenGL ES 2.0 and OpenGL 2.x
@@ -179,6 +181,7 @@ void GLWidget::paintGL()
         m_program->setUniformValue(m_colorUniformLoc, data->color);
         m_program->setUniformValue(m_minUniformLoc, data->min);
         m_program->setUniformValue(m_deltaUniformLoc, data->delta);
+        m_program->setUniformValue(m_matrixUniformLoc, data->matrix);
 
         if (!vbo) {
             vbo = new QOpenGLBuffer;
diff --git a/src/charts/glwidget_p.h b/src/charts/glwidget_p.h
index 920255fd..024e096a 100644
--- a/src/charts/glwidget_p.h
+++ b/src/charts/glwidget_p.h
@@ -79,6 +79,7 @@ private:
     int m_minUniformLoc;
     int m_deltaUniformLoc;
     int m_pointSizeUniformLoc;
+    int m_matrixUniformLoc;
     QOpenGLVertexArrayObject m_vao;
 
     QHash<const QAbstractSeries *, QOpenGLBuffer *> m_seriesBufferMap;
diff --git a/src/charts/xychart/glxyseriesdata.cpp b/src/charts/xychart/glxyseriesdata.cpp
index e5fc9e87..37da55b1 100644
--- a/src/charts/xychart/glxyseriesdata.cpp
+++ b/src/charts/xychart/glxyseriesdata.cpp
@@ -74,16 +74,30 @@ void GLXYSeriesDataManager::setPoints(QXYSeries *series, const AbstractDomain *d
     QVector<float> &array = data->array;
 
     bool logAxis = false;
+    bool reverseX = false;
+    bool reverseY = false;
     foreach (QAbstractAxis* axis, series->attachedAxes()) {
         if (axis->type() == QAbstractAxis::AxisTypeLogValue) {
             logAxis = true;
-            break;
+        }
+        if (axis->isReverse()) {
+            if (axis->orientation() == Qt::Horizontal)
+                reverseX = true;
+            else
+                reverseY = true;
+            if (reverseX && reverseY)
+                break;
         }
     }
-
     int count = series->count();
     int index = 0;
     array.resize(count * 2);
+    QMatrix4x4 matrix;
+    if (reverseX)
+        matrix.scale(-1.0, 1.0);
+    if (reverseY)
+        matrix.scale(1.0, -1.0);
+    data->matrix = matrix;
     if (logAxis) {
         // Use domain to resolve geometry points. Not as fast as shaders, but simpler that way
         QVector<QPointF> geometryPoints = domain->calculateGeometryPoints(series->pointsVector());
@@ -185,5 +199,35 @@ void GLXYSeriesDataManager::handleScatterMarkerSizeChange()
     }
 }
 
+void GLXYSeriesDataManager::handleAxisReverseChanged(const QList<QAbstractSeries *> &seriesList)
+{
+    bool reverseX = false;
+    bool reverseY = false;
+    foreach (QAbstractSeries *series, seriesList) {
+        if (QXYSeries *xyseries = qobject_cast<QXYSeries *>(series)) {
+            GLXYSeriesData *data = m_seriesDataMap.value(xyseries);
+            if (data) {
+                foreach (QAbstractAxis* axis, xyseries->attachedAxes()) {
+                    if (axis->isReverse()) {
+                        if (axis->orientation() == Qt::Horizontal)
+                            reverseX = true;
+                        else
+                            reverseY = true;
+                    }
+                    if (reverseX && reverseY)
+                        break;
+                }
+                QMatrix4x4 matrix;
+                if (reverseX)
+                    matrix.scale(-1.0, 1.0);
+                if (reverseY)
+                    matrix.scale(1.0, -1.0);
+                data->matrix = matrix;
+                data->dirty = true;
+            }
+        }
+    }
+}
+
 QT_CHARTS_END_NAMESPACE
 
diff --git a/src/charts/xychart/glxyseriesdata_p.h b/src/charts/xychart/glxyseriesdata_p.h
index 71a800ca..578ab217 100644
--- a/src/charts/xychart/glxyseriesdata_p.h
+++ b/src/charts/xychart/glxyseriesdata_p.h
@@ -44,6 +44,7 @@
 #include <QtCharts/QXYSeries>
 #include <QtGui/QVector3D>
 #include <QtGui/QVector2D>
+#include <QtGui/QMatrix4x4>
 
 QT_CHARTS_BEGIN_NAMESPACE
 
@@ -57,6 +58,19 @@ struct GLXYSeriesData {
     QAbstractSeries::SeriesType type;
     QVector2D min;
     QVector2D delta;
+    QMatrix4x4 matrix;
+public:
+    GLXYSeriesData &operator=(const GLXYSeriesData &data) {
+        array = data.array;
+        dirty = data.dirty;
+        color = data.color;
+        width = data.width;
+        type = data.type;
+        min = data.min;
+        delta = data.delta;
+        matrix = data.matrix;
+        return *this;
+    }
 };
 
 typedef QMap<const QXYSeries *, GLXYSeriesData *> GLXYDataMap;
@@ -83,6 +97,7 @@ public:
         foreach (GLXYSeriesData *data, m_seriesDataMap.values())
             data->dirty = false;
     }
+    void handleAxisReverseChanged(const QList<QAbstractSeries *> &seriesList);
 
 public Q_SLOTS:
     void cleanup();
diff --git a/src/chartsqml2/declarativerendernode.cpp b/src/chartsqml2/declarativerendernode.cpp
index 66784ecc..c11f6b00 100644
--- a/src/chartsqml2/declarativerendernode.cpp
+++ b/src/chartsqml2/declarativerendernode.cpp
@@ -96,9 +96,10 @@ static const char *vertexSource =
         "uniform highp vec2 min;\n"
         "uniform highp vec2 delta;\n"
         "uniform highp float pointSize;\n"
+        "uniform highp mat4 matrix;\n"
         "void main() {\n"
         "  vec2 normalPoint = vec2(-1, -1) + ((points - min) / delta);\n"
-        "  gl_Position = vec4(normalPoint, 0, 1);\n"
+        "  gl_Position = matrix * vec4(normalPoint, 0, 1);\n"
         "  gl_PointSize = pointSize;\n"
         "}";
 static const char *fragmentSource =
@@ -123,6 +124,7 @@ void DeclarativeRenderNode::initGL()
     m_minUniformLoc = m_program->uniformLocation("min");
     m_deltaUniformLoc = m_program->uniformLocation("delta");
     m_pointSizeUniformLoc = m_program->uniformLocation("pointSize");
+    m_matrixUniformLoc = m_program->uniformLocation("matrix");
 
     // Create a vertex array object. In OpenGL ES 2.0 and OpenGL 2.x
     // implementations this is optional and support may not be present
@@ -183,13 +185,7 @@ void DeclarativeRenderNode::setSeriesData(bool mapDirty, const GLXYDataMap &data
             const GLXYSeriesData *newData = i.value();
             if (!data || newData->dirty) {
                 data = new GLXYSeriesData;
-                data->array = newData->array;
-                data->color = newData->color;
-                data->dirty = newData->dirty;
-                data->width = newData->width;
-                data->type = newData->type;
-                data->min = newData->min;
-                data->delta = newData->delta;
+                *data = *newData;
             }
             m_xyDataMap.insert(i.key(), data);
         }
@@ -208,15 +204,8 @@ void DeclarativeRenderNode::setSeriesData(bool mapDirty, const GLXYDataMap &data
             const GLXYSeriesData *newData = i.value();
             if (i.value()->dirty) {
                 GLXYSeriesData *data = m_xyDataMap.value(i.key());
-                if (data) {
-                    data->array = newData->array;
-                    data->color = newData->color;
-                    data->dirty = newData->dirty;
-                    data->width = newData->width;
-                    data->type = newData->type;
-                    data->min = newData->min;
-                    data->delta = newData->delta;
-                }
+                if (data)
+                    *data = *newData;
             }
         }
     }
@@ -246,6 +235,7 @@ void DeclarativeRenderNode::renderGL()
         m_program->setUniformValue(m_colorUniformLoc, data->color);
         m_program->setUniformValue(m_minUniformLoc, data->min);
         m_program->setUniformValue(m_deltaUniformLoc, data->delta);
+        m_program->setUniformValue(m_matrixUniformLoc, data->matrix);
 
         if (!vbo) {
             vbo = new QOpenGLBuffer;
diff --git a/src/chartsqml2/declarativerendernode.h b/src/chartsqml2/declarativerendernode.h
index 3e3fe6a8..b21fa20b 100644
--- a/src/chartsqml2/declarativerendernode.h
+++ b/src/chartsqml2/declarativerendernode.h
@@ -74,6 +74,7 @@ private:
     int m_minUniformLoc;
     int m_deltaUniformLoc;
     int m_pointSizeUniformLoc;
+    int m_matrixUniformLoc;
     QOpenGLVertexArrayObject m_vao;
     QHash<const QAbstractSeries *, QOpenGLBuffer *> m_seriesBufferMap;
     bool m_renderNeeded;