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++ // Copyright (C) 2023 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
++
++ /*!
++ \example 3d/widgetgraphgallery
++ \meta tags {Graphs, Bar Graph, Custom Proxy, Scatter Graph, Custom Input Handler, Surface Graph, QCustom3DItem, Textured Surface}
++ \examplecategory {Data Visualization}
++ \title Graph Gallery
++ \ingroup qtgraphs_examples_3D
++ \brief Gallery of Bar, Scatter, and Surface graphs.
++
++ \e {Graph Gallery} demonstrates all three graph types and some of their special features.
++ The graphs have their own tabs in the application.
++
++ \image widgetgraphgallery-example.png
++ {3D surface plot with gradient coloring and customization options}
++
++ \include examples-run.qdocinc
++
++ \section1 Bar Graph
++
++ In the \uicontrol {Bar Graph} tab, create a 3D bar graph using Q3DBarWidgetItem and combine
++ the use of widgets to adjust various bar graph qualities. The example shows how to:
++
++ \list
++ \li Create an application with Q3DBarWidgetItem and some control widgets
++ \li Use QBar3DSeries and QBarDataProxy to set data to the graph
++ \li Adjust some graph and series properties using widget controls
++ \li Select a row or a column by clicking an axis label
++ \li Create a custom proxy to use with Q3DBarWidgetItem
++ \endlist
++
++ For information about interacting with the graph, see
++ \l{Qt Graphs Interacting with Data in 3D}{this page}.
++
++ \section2 Creating the Application
++
++ \list 1
++
++ \li In \c{bargraph.cpp}, instantiate QQuickWidget and Q3DBarsWidgetItem,
++ and set the QQuickWidget instance as the widget for Q3DBarsWidgetItem:
++
++ \snippet 3d/widgetgraphgallery/bargraph.cpp creation
++
++ \li Create a container widget, and horizontal and vertical layouts. Add
++ the graph and the vertical layout to the horizontal one:
++
++ \snippet 3d/widgetgraphgallery/bargraph.cpp adding to layout
++
++ \li Create another class to handle the data addition and other
++ interaction with the graph:
++
++ \snippet 3d/widgetgraphgallery/bargraph.cpp create the data handler
++ \endlist
++
++ \section2 Setting up the Bar Graph
++
++ \list 1
++ \li Set up the graph in the constructor of the \c GraphModifier class:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp set up the graph
++
++ \li Create the axes and the series into member variables to support
++ changing them:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp set up axes
++
++ \li Set some visual qualities for the graph:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp adjust visuals
++
++ \li Set up the axes and make them the active axes of the graph:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp activate axes
++
++ \li Give axis labels a small autorotation angle:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp auto angle
++
++ This is done to make them orient slightly toward the camera, which
++ improves axis label readability at extreme camera angles.
++
++ \li Initialize the visual properties of the series. Note that the second
++ series is initially not visible:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp initialize series visuals
++
++ \li Add the series to the graph:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp add series
++
++ \li Set the camera angle by calling the same method the camera angle
++ change button in the UI uses to cycle through various camera angles:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp invoke camera preset
++
++ \li The new camera preset is set to the graph:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp change the preset
++ \endlist
++
++ \section2 Adding Data to the Graph
++
++ At the end of the constructor, call a method that sets up the data:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp invoke data reset
++
++ This method adds data to the relevant series using proxies of the two series:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp set up data
++ \dots 0
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp populate series vie proxies
++
++ \section2 Using Widgets to Control the Graph
++
++ Continue by adding some widgets in \c{bargraph.cpp}.
++
++ \list 1
++ \li Add a slider:
++
++ \snippet 3d/widgetgraphgallery/bargraph.cpp creating a slider
++
++ \li Use the slider to rotate the graph instead of just using a mouse or
++ touch. Add it to the vertical layout:
++
++ \snippet 3d/widgetgraphgallery/bargraph.cpp adding the slider
++
++ \li Connect it to a method in \c GraphModifier:
++
++ \snippet 3d/widgetgraphgallery/bargraph.cpp connecting the slider
++
++ \li Create a slot in \c GraphModifier for the signal connection. Specify the
++ actual camera position along the orbit around the center point, instead
++ of specifying a preset camera angle:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp rotate camera
++ \endlist
++
++ You can now use the slider to rotate the graph.
++
++ Add more widgets to the vertical layout to control:
++
++ \list
++ \li Graph rotation
++ \li Label style
++ \li Camera preset
++ \li Background visibility
++ \li Grid visibility
++ \li Bar shading smoothness
++ \li Visibility of the second bar series
++ \li Value axis direction
++ \li Axis title visibility and rotation
++ \li Data range to be shown
++ \li Bar style
++ \li Selection mode
++ \li Theme
++ \li Shadow quality
++ \li Font
++ \li Font size
++ \li Axis label rotation
++ \li Data mode
++ \endlist
++
++ Some widget controls are intentionally disabled when in the \uicontrol {Custom Proxy Data}
++ data mode.
++
++ \section2 Selecting a Row or Column by Clicking an Axis Label
++
++ Selection by axis label is default functionality for bar graphs. For example,
++ you can select rows by clicking an axis label in the following way:
++
++ \list 1
++ \li Change selection mode to \c Row
++ \li Click a year label
++ \li The row with the clicked year is selected
++ \endlist
++
++ The same method works with \c Slice and \c Item flags, as long as
++ either \c Row or \c Column is set as well.
++
++ \section2 Zooming to Selection
++
++ As an example of adjusting the camera target, implement an animation of zooming to
++ selection via a button press. Animation initializations are done in the constructor:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp animation setup
++
++ Function \c{GraphModifier::zoomToSelectedBar()} contains the zooming functionality.
++ QPropertyAnimation \c m_animationCameraTarget targets
++ \l {Q3DGraphsWidgetItem::cameraTargetPosition}{cameraTargetPosition} property,
++ which takes a value normalized to the range (-1, 1).
++
++ Figure out where the selected bar is relative to axes, and use that as the end value for
++ \c{m_animationCameraTarget}:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp calculate target
++ \dots 0
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp set target
++
++ Then, rotate the camera so that it always points approximately to the center of
++ the graph at the end of the animation:
++
++ \snippet 3d/widgetgraphgallery/graphmodifier.cpp center camera
++
++ \section2 Model Proxy for Data
++
++ When you toggle \uicontrol {Model Proxy Data} data mode on, the graph in
++ the example uses an item model based dataset and the corresponding proxy.
++
++ \section3 RainfallData
++
++ Class \c RainfallData sets up a QItemModelBarDataProxy along with the series
++ and axes.
++
++ \list 1
++ \li We use a \c{std::array<double, 12>} to store the values of a year
++ indexed by month. The static \c readData() helper function reads
++ the data, returning a QList of them indexed by year:
++
++ \snippet 3d/widgetgraphgallery/rainfalldata.cpp 1
++ \dots
++
++ \li The QList represents a two dimensional array indexed by year and month,
++ respectively. From this, we populate a QRangeModel and pass it to
++ a QItemModelBarDataProxy() in the \c RainfallData class:
++
++ \snippet 3d/widgetgraphgallery/rainfalldata.cpp 0
++
++ \li Finally, add a function for getting the created series for displaying:
++
++ \snippet 3d/widgetgraphgallery/rainfalldata.h 0
++
++ \endlist
++
++ \section1 Scatter Graph
++
++ In the \uicontrol {Scatter Graph} tab, create a 3D scatter graph using
++ Q3DScatterWidgetItem. The example shows how to:
++
++ \list
++ \li Set up Q3DScatterWidgetItem graph
++ \li Use QScatterDataProxy to set data to the graph
++ \li Create and add a custom input handler
++ \endlist
++
++ For basic application creation, see \l {Bar Graph}.
++
++ \section2 Setting up the Scatter Graph
++
++ \list 1
++
++ \li Set up some visual qualities for the graph in the constructor of the
++ \c ScatterDataModifier:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 0
++
++ None of these settings are mandatory, but they serve to override graph
++ defaults. To observe the appearance with the preset defaults, the block
++ above can be commented out.
++
++ \li Create a QScatterDataProxy and the associated QScatter3DSeries. Set a
++ custom label format and mesh smoothing for the series and add it to the graph:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 1
++
++ \endlist
++
++ \section2 Adding Scatter Data
++
++ \list 1
++
++ \li In the \c ScatterDataModifier constructor, add data to the graph:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 2
++
++ \li The actual data addition is done in \c addData() method. First, configure the axes:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 3
++
++ You could do this also in the constructor of \c {ScatterDataModifier}. Doing it here
++ keeps the constructor simpler and the axes' configuration near the data.
++
++ \li Create a data array and populate it:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 4
++ \dots
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 5
++
++ \li Finally, tell the proxy to start using the data we gave it:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 6
++
++ \endlist
++
++ Now, the graph has the data and is ready for use. For information about adding widgets
++ to control the graph, see \l {Using Widgets to Control the Graph}.
++
++ \section2 Replacing Default Input Handling
++
++ To replace the default input handling mechanism, set the new input handlers of
++ Q3DScatterWidgetItem, which implements the custom behavior:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 8
++
++ \section2 Extending Mouse Event Handling
++
++ Implement a new \c{drag} event handler. It provides a mouse movement distance
++ for the axis dragging calculation (see
++ \l {Implementing Axis Dragging} for details):
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 8
++
++ \section2 Implementing Axis Dragging
++
++ \list 1
++ \li Start listening to the selection signal from the graph. Do that in the
++ constructor, and connect it to the \c handleElementSelected method:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 8
++
++ \li In \c {handleElementSelected}, check the type of the selection, and set
++ the internal state based on it:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 9
++
++ \li The actual dragging logic is implemented in the \c handleAxisDragging
++ method, which is called from \c {drag} event:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 10
++
++ \li In \c {handleAxisDragging}, first get the scene orientation from the
++ active camera:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 11
++
++ \li Calculate the modifiers for mouse movement direction based on the
++ orientation:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 12
++
++ \li Calculate the mouse movement, and modify it based on the y rotation of
++ the camera:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 13
++
++ \li Apply the moved distance to the correct axis:
++
++ \snippet 3d/widgetgraphgallery/scatterdatamodifier.cpp 14
++
++ \endlist
++
++ \section1 Surface Graph
++
++ In the \uicontrol {Surface Graph} tab, create a 3D surface graph using
++ Q3DSurfaceWidgetItem. The example shows how to:
++
++ \list
++ \li Set up a basic QSurfaceDataProxy and set data for it.
++ \li Use QHeightMapSurfaceDataProxy for showing 3D height maps.
++ \li Use topographic data to create 3D height maps.
++ \li Use three different selection modes for studying the graph.
++ \li Use axis ranges to display selected portions of the graph.
++ \li Set a custom surface gradient.
++ \li Add custom items and labels with QCustom3DItem and QCustom3DLabel.
++ \li Use custom input handler to enable zooming and panning.
++ \li Highlight an area of the surface.
++ \endlist
++
++ For basic application creation, see \l {Bar Graph}.
++
++ \section2 Simple Surface with Generated Data
++
++ \list 1
++
++ \li First, instantiate a new QSurfaceDataProxy and attach it to a new QSurface3DSeries:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 0
++
++ \li Fill the proxy with a simple square root and sine wave data. Create a
++ \c QSurfaceDataArray instance and add \c QSurfaceDataRow elements to it.
++ Set the created \c QSurfaceDataArray as the data array for the
++ QSurfaceDataProxy by calling \c{resetArray()}.
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 1
++ \endlist
++
++ \section2 Multiseries Height Map Data
++
++ Create the height map by instantiating a QHeightMapSurfaceDataProxy with a
++ QImage containing the height data. Use QHeightMapSurfaceDataProxy::setValueRanges()
++ to define the value range of the map. In the example, the map is from an
++ imaginary position of 34.0\unicode 0x00B0 N - 40.0\unicode 0x00B0 N and
++ 18.0\unicode 0x00B0 E - 24.0\unicode 0x00B0 E. These values are used to
++ position the map on the axes.
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 2
++
++ Add the other surface layers the same way, by creating a proxy and a series
++ for them using height map images.
++ -
++ \section2 Topographic Map Data
++
++ The topographic data is obtained from the National Land Survey of Finland.
++ It provides a product called \c{Elevation Model 2 m}, which is suitable for
++ this example.
++
++ The topography data is from Levi fell. The accuracy of the data is well
++ beyond the need, and therefore it is compressed and encoded into a PNG file.
++ The height value of the original ASCII data is encoded into RGB format using
++ a multiplier, as demonstrated in the code sample below. The multiplier is
++ calculated by dividing the largest 24-bit value with the highest point in
++ Finland.
++
++ QHeightMapSurfaceDataProxy converts only one-byte values. To utilize the
++ higher accuracy of the data from the National Land Survey of Finland, read
++ the data from the PNG file and decode it into a QSurface3DSeries.
++
++ \list 1
++ \li Define the encoding multiplier:
++
++ \snippet 3d/widgetgraphgallery/topographicseries.cpp 0
++
++ \li Perform the actual decoding:
++
++ \snippet 3d/widgetgraphgallery/topographicseries.cpp 1
++ \endlist
++
++ Now, a Surface Graph can consume the data via the proxy.
++
++ \section2 Selecting the Data Set
++
++ To demonstrate different proxies, the \uicontrol {Surface Graph} has three
++ radio buttons to switch between the series.
++
++ With \uicontrol {Sqrt & Sin}, the simple generated series is activated.
++
++ \list 1
++ \li Set the decorative features, such as enabling the grid for the
++ surface, and selecting the flat shading mode.
++ \li Define the axis label format and value ranges. Set automatic label
++ rotation to improve label readability at low camera angles.
++ \li Make sure the correct series is added to the graph and the others
++ are not.
++ \endlist
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 3
++
++ With \uicontrol {Multiseries Height Map}, the height map series are
++ activated and others are disabled. Auto-adjusting the Y-axis range works
++ well for the height map surface, so ensure it is set.
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 4
++
++ With \uicontrol {Textured Topography}, the topographic series is activated
++ and others are disabled. Activate a custom input handler for this series,
++ to be able to highlight areas on it:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 5
++
++ See \l {Use Custom Input Handler to Enable Zooming and Panning} for
++ information about the custom input handler for this data set.
++
++ \section2 Selection Modes
++
++ The three selection modes supported by Q3DSurfaceWidgetItem can be used with
++ radio buttons. To activate the selected mode or to clear it, add the
++ following inline methods:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.h 0
++
++ To support doing a slice selection to all visible series
++ in the graph simultaneously, add \c{QtGraphs3D::SelectionFlag::Slice} and
++ \c{QtGraphs3D::SelectionFlag::MultiSeries} flags for the row and column
++ selection modes.
++
++ \section2 Axis Ranges for Studying the Graph
++
++ The example has four slider controls for adjusting the min and max values
++ for the X and Z axes. When selecting the proxy, these sliders are adjusted
++ to match the axis ranges of the current data set:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 6
++
++ To add support for setting the X range from the widget controls to the
++ graph, add:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 7
++
++ Add the support for Z range the same way.
++
++ \section2 Custom Surface Gradients
++
++ With the \uicontrol {Sqrt & Sin} data set, custom surface gradients can be
++ taken into use with two push buttons. Define the gradient with
++ QLinearGradient, where the desired colors are set. Also, change the color
++ style to Q3DTheme::ColorStyle::RangeGradient to use the gradient.
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 8
++
++ \section2 Adding Custom Meshes to the Application
++
++ To add custom meshes tp the application:
++
++ \list
++ \li \b{For a cmake build}. Add the mesh files to \c{CMakeLists.txt}:
++
++ \badcode
++ set(graphgallery_resource_files
++ ...
++ "data/oilrig.mesh"
++ "data/pipe.mesh"
++ "data/refinery.mesh"
++ ...
++ )
++
++ qt6_add_resources(widgetgraphgallery "widgetgraphgallery"
++ PREFIX
++ "/"
++ FILES
++ ${graphgallery_resource_files}
++ )
++ \endcode
++
++ \li \b{For a qmake build}. Add the mesh files in the qrc resource file:
++
++ \badcode
++ <RCC>
++ <qresource prefix="/">
++ ...
++ <file>data/refinery.mesh</file>
++ <file>data/oilrig.mesh</file>
++ <file>data/pipe.mesh</file>
++ ...
++ </qresource>
++ </RCC>
++ \endcode
++ \endlist
++
++ \section2 Adding Custom Item to a Graph
++
++ With the \uicontrol {Multiseries Height Map} data set, custom items are
++ inserted into the graph and can be toggled on or off using checkboxes. Other
++ visual changes can also be controlled with another set of checkboxes,
++ including see-through for the two top layers, and a highlight for the bottom
++ layer.
++
++ \list
++ \li Creating a small QImage. Fill it with a single color to use as the color for the
++ custom object:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 9
++
++ \li Specify the position of the item in a variable. The position can then
++ be used for removing the correct item from the graph:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 10
++
++ \li Create a new QCustom3DItem with all the parameters:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 11
++
++ \li Add the item to the graph:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 12
++ \endlist
++
++ \section2 Adding Custom Label to a Graph
++
++ Adding a custom label is very similar to adding a custom item. For the
++ label, a custom mesh is not needed, but just a QCustom3DLabel instance:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 13
++
++ \section2 Removing Custom Item from a Graph
++
++ To remove a specific item from the graph, call \c removeCustomItemAt() with
++ the position of the item:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 14
++
++ \note Removing a custom item from the graph also deletes the object. To
++ preserve the item, use the \c releaseCustomItem() method instead.
++
++ \section2 Texture to a Surface Series
++
++ With the \uicontrol {Textured Topography} data set, create a map texture to
++ be used with the topographic height map.
++
++ Set an image to be used as the texture on a surface with
++ QSurface3DSeries::setTextureFile(). Add a check box to control if the
++ texture is set or not, and a handler to react to the checkbox state:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 15
++
++ The image in this example is read from a JPG file. Setting an empty file
++ with the method clears the texture, and the surface uses the gradients or
++ colors from the theme.
++
++ \section2 Use Custom Input Handler to Enable Zooming and Panning
++
++ With the \uicontrol {Textured Topography} data set, create a custom input
++ handler to highlight the selection on the graph and allow panning the graph.
++
++ The panning implementation is similar to the one shown in
++ \l{Implementing Axis Dragging}. The difference is that, in this example, you
++ only follow the X and Z axes and don't allow dragging the surface outside
++ the graph. To limit the dragging, follow the limits of the axes and do
++ nothing if going outside the graph:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 17
++
++ For zooming, catch the \c wheelEvent and adjust the X and Y axis ranges
++ according to the delta value on QWheelEvent. Adjust the Y axis so that the
++ aspect ratio between the Y axis and the XZ plane stays the same. This
++ prevents getting a graph in which the height is exaggerated:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 18
++
++ Next, add some limits to the zoom level, so that it won't get too near to or
++ far from the surface. For instance, if the value for the X axis gets below
++ the allowed limit, that is, zooming gets too far, the value is set to the
++ minimum allowed value. If the range is going to below the range minimum,
++ both ends of the axis are adjusted so that the range stays at the limit:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 19
++
++ \section2 Highlight an Area of the Surface
++
++ To implement a highlight to be displayed on the surface, create a copy of
++ the series and add some offset to the y value. In this example, the class
++ \c HighlightSeries implements the creation of the copy in its
++ \c handlePositionChange method.
++
++ First, give \c HighlightSeries the pointer to the original series, and then
++ start listening to the QSurface3DSeries::selectedPointChanged signal:
++
++ \snippet 3d/widgetgraphgallery/highlightseries.cpp 0
++
++ When the signal triggers, check that the position is valid. Then, calculate
++ he ranges for the copied area, and check that they stay within the bounds.
++ Finally, fill the data array of the highlight series with the range from the
++ data array of the topography series:
++
++ \snippet 3d/widgetgraphgallery/highlightseries.cpp 1
++
++ \section2 A Gradient to the Highlight Series
++
++ Since the \c HighlightSeries is a QSurface3DSeries, all the decoration
++ methods a series can have are available. In this example, add a gradient to
++ emphasize the elevation. Because the suitable gradient style depends on the
++ range of the Y axis and we change the range when zooming, the gradient color
++ positions need to be adjusted as the range changes. Do this by
++ defining proportional values for the gradient color positions:
++
++ \snippet 3d/widgetgraphgallery/highlightseries.cpp 2
++
++ The gradient modification is done in the \c handleGradientChange method, so
++ connect it to react to changes on the Y axis:
++
++ \snippet 3d/widgetgraphgallery/surfacegraphmodifier.cpp 16
++
++ When a change in the Y axis max value happens, calculate the new gradient
++ color positions:
++
++ \snippet 3d/widgetgraphgallery/highlightseries.cpp 3
++
++ \section1 Example Contents
++ */