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Surface3DNode QML Type

Describes the usage of the 3D surface graph node. More...

Import Statement: import QtGraphs
Inherits:

GraphsNode

Properties

Signals

Methods

Detailed Description

This type enables developers to render a surface graph node in 3D with Qt Quick.

You will need to import the Qt Graphs module to use this type:

import QtGraphs

After that you can use Surface3DNode in your qml files:

import QtQuick
import QtGraphs

View3D {
    width: 640
    height: 480

    Surface3DNode {
        width: parent.width
        height: parent.height
        Surface3DSeries {
            itemLabelFormat: "Pop density at (@xLabel N, @zLabel E): @yLabel"
            ItemModelSurfaceDataProxy {
                itemModel: dataModel
                // Mapping model roles to surface series rows, columns, and values.
                rowRole: "longitude"
                columnRole: "latitude"
                yPosRole: "pop_density"
            }
        }

        onTapped: {
            // Disable the default input handler
            unsetDefaultTapHandler()
            // Implement own custom event handler
            console.log("Custom tap event handler")
        }
    }
    ListModel {
        id: dataModel
        ListElement{ longitude: "20"; latitude: "10"; pop_density: "4.75"; }
        ListElement{ longitude: "21"; latitude: "10"; pop_density: "3.00"; }
        ListElement{ longitude: "22"; latitude: "10"; pop_density: "1.24"; }
        ListElement{ longitude: "23"; latitude: "10"; pop_density: "2.53"; }
        ListElement{ longitude: "20"; latitude: "11"; pop_density: "2.55"; }
        ListElement{ longitude: "21"; latitude: "11"; pop_density: "2.03"; }
        ListElement{ longitude: "22"; latitude: "11"; pop_density: "3.46"; }
        ListElement{ longitude: "23"; latitude: "11"; pop_density: "5.12"; }
        ListElement{ longitude: "20"; latitude: "12"; pop_density: "1.37"; }
        ListElement{ longitude: "21"; latitude: "12"; pop_density: "2.98"; }
        ListElement{ longitude: "22"; latitude: "12"; pop_density: "3.33"; }
        ListElement{ longitude: "23"; latitude: "12"; pop_density: "3.23"; }
        ListElement{ longitude: "20"; latitude: "13"; pop_density: "4.34"; }
        ListElement{ longitude: "21"; latitude: "13"; pop_density: "3.54"; }
        ListElement{ longitude: "22"; latitude: "13"; pop_density: "1.65"; }
        ListElement{ longitude: "23"; latitude: "13"; pop_density: "2.67"; }
    }
}

See also Surface3DSeries, ItemModelSurfaceDataProxy, Bars3DNode, Scatter3DNode, and Qt Graphs C++ Classes for 3D.

Property Documentation

aspectRatio : real

The ratio of the graph scaling between the longest axis on the horizontal plane and the y-axis. Defaults to 2.0.

Note: Has no effect on Bars3D.

See also horizontalAspectRatio.

axisX : Value3DAxis

The active x-axis.

If an axis is not given, a temporary default axis with no labels and an automatically adjusting range is created. This temporary axis is destroyed if another axis is explicitly set to the same orientation.

axisY : Value3DAxis

The active y-axis.

If an axis is not given, a temporary default axis with no labels and an automatically adjusting range is created. This temporary axis is destroyed if another axis is explicitly set to the same orientation.

axisZ : Value3DAxis

The active z-axis.

If an axis is not given, a temporary default axis with no labels and an automatically adjusting range is created. This temporary axis is destroyed if another axis is explicitly set to the same orientation.

customItemList : list<Custom3DItem>

The list of Custom3DItem items added to the graph. The graph takes ownership of the added items.

flipHorizontalGrid : bool

In some use cases the horizontal axis grid is mostly covered by the surface, so it can be more useful to display the horizontal axis grid on top of the graph rather than on the bottom. A typical use case for this is showing 2D spectrograms using orthoGraphic projection with a top-down viewpoint.

If false, the horizontal axis grid and labels are drawn on the horizontal background of the graph. If true, the horizontal axis grid and labels are drawn on the opposite side of the graph from the horizontal background. Defaults to false.

gridLineType : Graphs3D.GridLineType

Defines whether the grid lines type is Graphs3D.GridLineType.Shader or Graphs3D.GridLineType.Geometry.

This value affects all grid lines.

See also Graphs3D.GridLineType.

horizontalAspectRatio : real

The ratio of the graph scaling between the x-axis and z-axis. The value of 0.0 indicates automatic scaling according to axis ranges. Defaults to 0.0.

Note: Has no effect on Bars3DNode, which handles scaling on the horizontal plane via the barThickness and barSpacing properties. Polar graphs also ignore this property.

See also aspectRatio, polar, Bars3DNode::barThickness, and Bars3DNode::barSpacing.

labelMargin : real

This property specifies the margin for the placement of the axis labels.

Negative values place the labels inside the plot-area while positive values place them outside the plot-area. Label automatic rotation is disabled when the value is negative. Defaults to 0.1

See also QAbstract3DAxis::labelAutoAngle.

locale : locale

Sets the locale used for formatting various numeric labels. Defaults to the "C" locale.

See also Value3DAxis::labelFormat.

margin : real

The absolute value used for the space left between the edge of the plottable graph area and the edge of the graph background.

If the margin value is negative, the margins are determined automatically and can vary according to the size of the items in the series and the type of the graph. The value is interpreted as a fraction of the y-axis range if the graph aspect ratios have not been changed from the default values. Defaults to -1.0.

Note: Setting a smaller margin for a scatter graph than the automatically determined margin can cause the scatter items at the edges of the graph to overlap with the graph background.

Note: On scatter and surface graphs, if the margin is small in comparison to the axis label size, the positions of the edge labels of the axes are adjusted to avoid overlap with the edge labels of the neighboring axes.

optimizationHint : Graphs3D.OptimizationHint

Specifies whether the default or legacy mode is used for rendering optimization.

The default mode uses instanced rendering, and provides the full feature set at the best level of performance on most systems. The static mode optimizes graph rendering and is ideal for large non-changing data sets. It is slower with dynamic data changes and item rotations. Selection is not optimized, so using the static mode with massive data sets is not advisable. Legacy mode renders all items in th graph individually, without instancing. It should be used only if default mode does not work, that is the same as if the target system does not support instancing. Defaults to Default.

Note: On some environments, large graphs using static optimization may not render, because all of the items are rendered using a single draw call, and different graphics drivers support different maximum vertice counts per call. This is mostly an issue on 32bit and OpenGL ES2 platforms. To work around this issue, choose an item mesh with a low vertex count or use the point mesh.

See also Abstract3DSeries::mesh and Graphs3D.OptimizationHint.

polar : bool

If true, the horizontal axes are changed into polar axes. The x-axis becomes the angular axis and the z-axis becomes the radial axis. Polar mode is not available for bar graphs.

Defaults to false.

See also radialLabelOffset.

queriedGraphPosition : vector3d [read-only]

This read-only property contains the latest graph position values along each axis queried using Scene3D::graphPositionQuery. The values are normalized to range [-1, 1]. If the queried position was outside the graph bounds, the values will not reflect the real position, but will instead be some undefined position outside the range [-1, 1]. The value will be undefined until a query is made.

There is no single correct 3D coordinate to match a particular screen position, so to be consistent, the queries are always done against the inner sides of an invisible box surrounding the graph.

Note: Bar graphs only allow querying graph position at the graph floor level, so the y-value is always zero for bar graphs and valid queries can be only made at screen positions that contain the floor of the graph.

See also Scene3D::graphPositionQuery.

radialLabelOffset : real

This property specifies the normalized horizontal offset for the axis labels of the radial polar axis. The value 0.0 indicates that the labels should be drawn next to the 0-angle angular axis grid line. The value 1.0 indicates that the labels are drawn in their usual place at the edge of the graph background. This property is ignored if the polar property value is false. Defaults to 1.0.

See also polar.

selectedElement : Graphs3D.ElementType [read-only]

The element selected in the graph.

This property can be used to query the selected element type. The type is valid until a new selection is made in the graph and the selectedElementChanged signal is emitted.

The signal can be used for example for implementing customized input handling, as demonstrated by the Axis Handling example.

See also selectedLabelIndex(), selectedAxis(), selectedCustomItemIndex(), selectedCustomItem(), Bars3DNode::selectedSeries, Scatter3DNode::selectedSeries, Scene3D::selectionQueryPosition, and Graphs3D.ElementType.

selectedSeries : Surface3DSeries [read-only]

The selected series or null. If selectionMode has the MultiSeries flag set, this property holds the series which owns the selected point.

selectionMode : Graphs3D.SelectionMode

The active selection mode in the graph. One of the graphs3d.selectionflag enum values.

seriesList : list<Surface3DSeries> [default]

This property holds the series of the graph. By default, this property contains an empty list. To set the series, either use the addSeries() function or define them as children of the graph.

theme : GraphsTheme

The active theme of the graph.

See also GraphsTheme.

Signal Documentation

axisXChanged(ValueAxis3D axis)

This signal is emitted when axisX changes to axis.

Note: The corresponding handler is onAxisXChanged.

axisYChanged(ValueAxis3D axis)

This signal is emitted when axisY changes to axis.

Note: The corresponding handler is onAxisYChanged.

axisZChanged(ValueAxis3D axis)

This signal is emitted when axisZ changes to axis.

Note: The corresponding handler is onAxisZChanged.

flipHorizontalGridChanged(bool flip)

This signal is emitted when flipHorizontalGrid changes to flip.

Note: The corresponding handler is onFlipHorizontalGridChanged.

selectedSeriesChanged(Surface3DSeries series)

This signal is emitted when selectedSeries changes to series.

Note: The corresponding handler is onSelectedSeriesChanged.

Method Documentation

qsizetype addCustomItem(Custom3DItem item)

Adds a Custom3DItem item to the graph. Graph takes ownership of the added item.

Returns index to the added item if add was successful, -1 if trying to add a null item, and index of the item if trying to add an already added item.

See also removeCustomItems(), removeCustomItem(), and removeCustomItemAt().

void addSeries(Surface3DSeries series)

Adds the series to the graph.

See also GraphsNode::hasSeries().

void clearSelection()

Clears selection from all attached series.

void doPicking(QPoint point)

Performs picking using view coordinates from point on the elements of the graph, selecting the first item hit. Default input handling performs this upon receiving the onTapped event.

See also selectedElement.

void doRayPicking(QVector3D origin, QVector3D direction)

Performs picking starting from origin and in direction on the elements of the graph, selecting the first item hit.

See also selectedElement.

bool hasSeries(Abstract3DSeries series)

Returns whether the series has already been added to the graph.

void releaseCustomItem(Custom3DItem item)

Gets ownership of item back and removes the item from the graph.

Note: If the same item is added back to the graph, the texture file needs to be re-set.

See also Custom3DItem::textureFile.

void removeCustomItem(Custom3DItem item)

Removes the custom item. Deletes the resources allocated to it.

void removeCustomItemAt(vector3d position)

Removes all custom items at position. Deletes the resources allocated to them.

void removeCustomItems()

Removes all custom items. Deletes the resources allocated to them.

void removeSeries(Surface3DSeries series)

Removes the series from the graph.

See also GraphsNode::hasSeries().

Abstract3DAxis selectedAxis()

Can be used to get the selected axis after receiving selectedElementChanged signal with any label type. Selection is valid until the next selectedElementChanged signal.

Returns the selected axis, or null.

See also selectedElement.

Custom3DItem selectedCustomItem()

Can be used to get the selected custom item after receiving selectedElementChanged signal with ElementType.CustomItem type. Ownership of the item remains with the graph. Selection is valid until the next selectedElementChanged signal.

Returns the selected custom item, or null.

See also selectedElement.

qsizetype selectedCustomItemIndex()

Can be used to query the index of the selected custom item after receiving selectedElementChanged signal with ElementType.CustomItem type. Selection is valid until the next selectedElementChanged signal.

Returns index of the selected custom item, or -1.

See also selectedElement.

int selectedLabelIndex()

Can be used to query the index of the selected label after receiving selectedElementChanged signal with any label type. Selection is valid until the next selectedElementChanged signal.

Returns index of the selected label, or -1.

See also selectedElement.

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