Qwt3DRenderContext结构体 参考

Bundles all widget resources that drawables need during rendering 更多...

#include <qwt3d_render_context.h>

Public 成员函数
QPointF	worldToScreen (const Triple &world) const
	Projects a world-space point to screen pixel coordinates
Triple	screenToWorld (const QPointF &screen) const
	Unprojects screen pixel coordinates to a world-space point
Triple	relativePosition (Triple rel) const
	Converts a relative viewport position to world coordinates

Public 属性
QMatrix4x4	modelView
QMatrix4x4	projection
QSize	viewport
QOpenGLShaderProgram *	lineShader = nullptr
QOpenGLShaderProgram *	polygonShader = nullptr
QOpenGLShaderProgram *	textShader = nullptr

详细描述

Bundles all widget resources that drawables need during rendering

A value struct constructed per-call-site in Qwt3DPlot::paintGL() with the matrices, viewport, and shared shader programs current at that moment. Passed by const reference down the drawable draw chain, replacing the former Qwt3DPlot* back-pointer baked into Qwt3DDrawable (deferred smell #1, resolved).

The coordinate-conversion methods (worldToScreen, screenToWorld, relativePosition) are pure CPU math over the stored matrices and viewport — no OpenGL calls — so the context is self-contained and copyable.

// Constructed in paintGL() per draw phase:
Qwt3DRenderContext ctx;
ctx.modelView = d->m_modelView;
ctx.projection = d->m_projection;
ctx.viewport = viewportSize();
ctx.lineShader = d->m_lineShader;
ctx.polygonShader = d->m_polygonShader;
ctx.textShader = d->m_textShader;
 
d->m_coordinates.draw(ctx);

成员函数说明

relativePosition()

Triple Qwt3DRenderContext::relativePosition

(

Triple

rel

)

const

Converts a relative viewport position to world coordinates

参数

rel	Relative position in viewport coordinates [0..1]

返回

Corresponding world coordinates

Scales the relative position by the viewport dimensions to obtain screen pixel coordinates, then unprojects to world space.

screenToWorld()

Triple Qwt3DRenderContext::screenToWorld

(

const QPointF &

screen

)

const

Unprojects screen pixel coordinates to a world-space point

参数

screen

Screen-space point (pixel coordinates)

返回

World-space Triple

Uses the inverse of the CPU-side modelView and projection matrices to unproject screen coordinates. The z-component is determined by the near plane (z=0 in NDC).

worldToScreen()

QPointF Qwt3DRenderContext::worldToScreen

(

const Triple &

world

)

const

Projects a world-space point to screen pixel coordinates

参数

world

World-space Triple

返回

Screen-space QPointF (pixel coordinates)

Uses the CPU-side modelView and projection matrices to transform world coordinates to normalized device coordinates, then maps to viewport pixels.

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该结构体的文档由以下文件生成:

• /home/runner/work/QWT/QWT/src/plot3d/qwt3d_render_context.h
• /home/runner/work/QWT/QWT/src/plot3d/qwt3d_render_context.cpp