Qwt3DBar类 参考

3D bar chart item with VBO/VAO rendering 更多...

#include <qwt3d_bar.h>

类 Qwt3DBar 继承关系图:

类
class	PrivateData

Public 类型
enum	BarStyle { Filled , FilledMesh , Wireframe }
	Bar rendering style 更多...

Public 成员函数
	Qwt3DBar ()
	Constructs an empty bar chart item
	~Qwt3DBar () override
	Destructor — releases GL resources and data
void	setSamples (const QVector< QwtPoint3D > &samples)
	Set bar positions and heights from 3D points (x,y = footprint center, z = height)
void	setSamples (const QVector< double > &x, const QVector< double > &heights)
	Set bar positions (x) and heights along the y = 0 row
void	setSamples (double **z, int columns, int rows, double minX, double maxX, double minY, double maxY)
	Set a grid of bars from a z-value matrix with an explicit x/y domain
void	setSamples (const Qwt3DFunctionData &data)
	Set a grid of bars from a Qwt3DFunctionData result (modern vector API)
double	barWidth () const
	Returns the bar footprint width (<= 0 means auto)
void	setBarWidth (double w)
	Sets the bar footprint width (<= 0 selects auto = 80% of spacing)
double	barDepth () const
	Returns the bar footprint depth (<= 0 means auto)
void	setBarDepth (double d)
	Sets the bar footprint depth (<= 0 selects auto = 80% of spacing)
double	baseline () const
	Returns the baseline z value (bottom of positive bars)
void	setBaseline (double z)
	Sets the baseline z value
BarStyle	barStyle () const
	Returns the bar rendering style
void	setBarStyle (BarStyle style)
	Sets the bar rendering style
void	setDataColor (Qwt3DColor *color)
	Sets the data color functor (takes ownership)
const Qwt3DColor *	dataColor () const
	Returns the data color functor
void	invalidateColors ()
	Marks per-vertex colors as stale, triggering a VBO rebuild on the next draw
RGBA	meshColor () const
	Returns the mesh line color
void	setMeshColor (RGBA color)
	Sets the mesh line color
double	meshLineWidth () const
	Returns the mesh line width
void	setMeshLineWidth (double width)
	Sets the mesh line width
int	rtti () const override
	运行时类型信息
void	draw () override
	Draw the item using the current GL context
ParallelEpiped	hull () const override
	Get the bounding hull of the item in 3D space
void	populateLegendColors (ColorVector &colors) const override
	Populate the legend color vector from the item's color functor
QVector< QwtPoint3D >	samples () const
	Returns 1D bar samples (empty if 2D grid data was loaded)
bool	isGridData () const
	Returns true if 2D grid data was loaded
int	gridColumns () const
	Returns grid columns (valid only if isGridData())
int	gridRows () const
	Returns grid rows (valid only if isGridData())
double	gridMinX () const
	Returns grid x minimum (valid only if isGridData())
double	gridMaxX () const
	Returns grid x maximum (valid only if isGridData())
double	gridMinY () const
	Returns grid y minimum (valid only if isGridData())
double	gridMaxY () const
	Returns grid y maximum (valid only if isGridData())
std::vector< std::vector< double > >	gridZValues () const
	Returns the raw z matrix (valid only if isGridData(), empty otherwise)
Public 成员函数 继承自 Qwt3DPlotItem
	Qwt3DPlotItem ()
	Default constructor
virtual	~Qwt3DPlotItem ()
	Destructor — detaches from any plot
void	attach (Qwt3DPlot *plot)
	Attach the item to a plot
void	detach ()
	Detach the item from its plot
Qwt3DPlot *	plot () const
	Get the plot this item is attached to
void	setTitle (const QString &title)
	Set the item title
QString	title () const
	Get the item title
void	setZ (double z)
	Set the z-order value (controls draw sequence)
double	z () const
	Get the z-order value
void	setVisible (bool on)
	Set item visibility
bool	isVisible () const
	Check if the item is visible
virtual void	itemChanged ()
	Notify the plot that the item has changed

详细描述

3D bar chart item with VBO/VAO rendering

Qwt3DBar is a Qwt3DPlotItem that renders 3D bar chart data using modern OpenGL (VBO/VAO + GLSL shaders). Each sample becomes an axis-aligned cuboid ("bar") whose height encodes the scalar value.

Two data shapes are supported:

• A 1D series of bars placed freely on the xy-plane (setSamples with QwtPoint3D, where (x,y) is the footprint center and z is the bar height).
• A 2D grid of bars (bar3 / 3D histogram) sampled over a rectangular x/y domain, where z[i][j] is the height at cell (i,j).

The item manages its own bar specifications, color mapping, and GL resources (VBO, VAO, EBO, shader program). Geometry is uploaded to GPU memory when dirty and reused across frames until the data changes.

Bars reuse the lit surface shader (Blinn-Phong) with flat per-face normals, so they respond to Qwt3DPlot::enableLighting(). An optional edge mesh is drawn in a second pass for the FilledMesh / Wireframe styles.

auto plot = new Qwt3DPlot(parent);
 
auto bars = new Qwt3DBar();
bars->setSamples(zMatrix, columns, rows, minX, maxX, minY, maxY);
bars->setBarStyle(Qwt3DBar::FilledMesh);
bars->setDataColor(new Qwt3DColorMapColor("viridis"));
bars->attach(plot);

参见

Qwt3DPlotItem, Qwt3DPlot, Qwt3DColor

成员枚举类型说明

BarStyle

enum Qwt3DBar::BarStyle

Bar rendering style

枚举值
Filled	Filled bars, no edges
FilledMesh	Filled bars with separately colored edge lines
Wireframe	Edge lines only

成员函数说明

draw()

void Qwt3DBar::draw ( )

overridevirtual

Draw the item using the current GL context

实现了 Qwt3DPlotItem.

hull()

ParallelEpiped Qwt3DBar::hull ( ) const

overridevirtual

Get the bounding hull of the item in 3D space

实现了 Qwt3DPlotItem.

populateLegendColors()

void Qwt3DBar::populateLegendColors ( ColorVector &  colors ) const

overridevirtual

Populate the legend color vector from the item's color functor

重载 Qwt3DPlotItem .

rtti()

int Qwt3DBar::rtti ( ) const

overridevirtual

运行时类型信息

返回

Rtti_Plot3DBar (= 1002)

重载 Qwt3DPlotItem .

samples()

QVector< QwtPoint3D > Qwt3DBar::samples

(

)

const

Returns 1D bar samples (empty if 2D grid data was loaded)

Reconstructs QVector<QwtPoint3D> from internal bar specs.

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该类的文档由以下文件生成:

• /home/runner/work/QWT/QWT/src/plot3d/qwt3d_bar.h
• /home/runner/work/QWT/QWT/src/plot3d/qwt3d_bar.cpp