Allow surface rows and cols be in ascending or descending XZ order

This allows adding rows that have smaller Z-value than the
previously added row instead of being forced to insert rows
into the beginning of the data array in these cases.

Task-number: QTRD-2428
Change-Id: I4dc6c5a48a55ca494a2372f917aa7447f61f336e
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>

1 files changed, 11 insertions, 10 deletions

diff --git a/src/datavisualization/data/qsurfacedataproxy.cpp b/src/datavisualization/data/qsurfacedataproxy.cpp
index 2e66bb5b..f8f2c900 100644
--- a/src/datavisualization/data/qsurfacedataproxy.cpp
+++ b/src/datavisualization/data/qsurfacedataproxy.cpp
@@ -28,8 +28,8 @@ QT_BEGIN_NAMESPACE_DATAVISUALIZATION
  * \brief Base proxy class for Q3DSurface.
  * \since Qt Data Visualization 1.0
  *
- * QSurfaceDataProxy takes care of surface related data handling. The QSurfaceDataProxy handles the data
- * in rows and for this it provides two auxiliary typedefs. QSurfaceDataArray is a QList for
+ * QSurfaceDataProxy takes care of surface related data handling. The QSurfaceDataProxy handles the
+ * data in rows and for this it provides two auxiliary typedefs. QSurfaceDataArray is a QList for
  * controlling the rows. For rows there is a QVector QSurfaceDataRow which contains QSurfaceDataItem
  * objects. See Q3DSurface documentation and basic sample code there how to feed the data for the
  * QSurfaceDataProxy.
@@ -41,17 +41,18 @@ QT_BEGIN_NAMESPACE_DATAVISUALIZATION
  * If you use QSurfaceDataRow pointers to directly modify data after adding the array to the proxy,
  * you must also emit proper signal to make the graph update.
  *
- * To make a sensible surface, the X-value of each successive item in the same row must be greater than the
- * previous item in that row, and the the Z-value of each successive item in a column  must be greater than
- * the previous item in that column.
+ * To make a sensible surface, the X-value of each successive item in all rows must be
+ * either ascending or descending throughout the row.
+ * Similarly, the Z-value of each successive item in all columns must be either ascending or
+ * descending throughout the column.
  *
- * \note In the initial release, only surfaces with straight rows and columns are fully supported. Any row
- * with items that do not have the exact same Z-value or any columns with items that do not have the exact
- * same X-value may get clipped incorrectly if the whole surface doesn't fit to the visible X or Z axis
- * ranges.
+ * \note Currently only surfaces with straight rows and columns are fully supported. Any row
+ * with items that do not have the exact same Z-value or any column with items that do not have
+ * the exact same X-value may get clipped incorrectly if the whole surface doesn't completely fit
+ * in the visible X or Z axis ranges.
  *
  * \note Surfaces with less than two rows or columns are not considered valid surfaces and will
- * not get rendered.
+ * not be rendered.
  *
  * \sa {Qt Data Visualization Data Handling}
  */