Hello GL2示例#
Hello GL2示例演示了Qt中提供的与OpenGL相关的类的基本使用。
在这个示例中，小部件对应的顶级窗口在其生命周期内可以改变几次。每次发生这种情况时，QOpenGLWidget的相关上下文都被销毁并创建一个新的，需要我们清理GL资源。
等效的C++示例在QOpenGLContext.aboutToBeDestroyed()信号发出时执行此清理。然而，在Qt for Python中，我们不能依赖于在析构函数中发出的此信号。
因此，我们在GLWidget.hideEvent()中执行清理。
接下来将调用initializeGL()，在那里我们可以重新创建所有资源。
# Copyright (C) 2023 The Qt Company Ltd.
# Copyright (C) 2013 Riverbank Computing Limited.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
"""PySide6 port of the opengl/hellogl2 example from Qt v6.x"""
from argparse import ArgumentParser, RawTextHelpFormatter
import sys
from PySide6.QtCore import Qt
from PySide6.QtGui import QSurfaceFormat
from PySide6.QtWidgets import (QApplication, QMessageBox)
try:
from mainwindow import MainWindow
from glwidget import GLWidget
except ImportError:
app = QApplication(sys.argv)
message_box = QMessageBox(QMessageBox.Critical, "OpenGL hellogl",
"PyOpenGL must be installed to run this example.",
QMessageBox.Close)
message_box.setDetailedText("Run:\npip install PyOpenGL PyOpenGL_accelerate")
message_box.exec()
sys.exit(1)
if __name__ == '__main__':
app = QApplication(sys.argv)
parser = ArgumentParser(description="hellogl2",
formatter_class=RawTextHelpFormatter)
parser.add_argument('--multisample', '-m', action='store_true',
help='Use Multisampling')
parser.add_argument('--coreprofile', '-c', action='store_true',
help='Use Core Profile')
parser.add_argument('--transparent', '-t', action='store_true',
help='Transparent Windows')
options = parser.parse_args()
fmt = QSurfaceFormat()
fmt.setDepthBufferSize(24)
if options.multisample:
fmt.setSamples(4)
if options.coreprofile:
fmt.setVersion(3, 2)
fmt.setProfile(QSurfaceFormat.CoreProfile)
QSurfaceFormat.setDefaultFormat(fmt)
GLWidget.set_transparent(options.transparent)
main_window = MainWindow()
if options.transparent:
main_window.setAttribute(Qt.WA_TranslucentBackground)
main_window.setAttribute(Qt.WA_NoSystemBackground, False)
main_window.show()
res = app.exec()
sys.exit(res)
# Copyright (C) 2023 The Qt Company Ltd.
# Copyright (C) 2013 Riverbank Computing Limited.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
import ctypes
from PySide6.QtCore import Signal, Slot, Qt, QSize, QPointF
from PySide6.QtGui import (QVector3D, QOpenGLFunctions,
QMatrix4x4, QOpenGLContext, QSurfaceFormat)
from PySide6.QtOpenGL import (QOpenGLVertexArrayObject, QOpenGLBuffer,
QOpenGLShaderProgram, QOpenGLShader)
from PySide6.QtOpenGLWidgets import QOpenGLWidget
from OpenGL import GL
from shiboken6 import VoidPtr
from logo import Logo
FRAGMENT_SHADER_SOURCE_CORE = """#version 150
in highp vec3 vert;
in highp vec3 vertNormal;
out highp vec4 fragColor;
uniform highp vec3 lightPos;
void main() {
highp vec3 L = normalize(lightPos - vert);
highp float NL = max(dot(normalize(vertNormal), L), 0.0);
highp vec3 color = vec3(0.39, 1.0, 0.0);
highp vec3 col = clamp(color * 0.2 + color * 0.8 * NL, 0.0, 1.0);
fragColor = vec4(col, 1.0);
}"""
FRAGMENT_SHADER_SOURCE = """varying highp vec3 vert;
varying highp vec3 vertNormal;
uniform highp vec3 lightPos;
void main() {
highp vec3 L = normalize(lightPos - vert);
highp float NL = max(dot(normalize(vertNormal), L), 0.0);
highp vec3 color = vec3(0.39, 1.0, 0.0);
highp vec3 col = clamp(color * 0.2 + color * 0.8 * NL, 0.0, 1.0);
gl_FragColor = vec4(col, 1.0);
}"""
VERTEX_SHADER_SOURCE_CORE = """#version 150
in vec4 vertex;
in vec3 normal;
out vec3 vert;
out vec3 vertNormal;
uniform mat4 projMatrix;
uniform mat4 mvMatrix;
uniform mat3 normalMatrix;
void main() {
vert = vertex.xyz;
vertNormal = normalMatrix * normal;
gl_Position = projMatrix * mvMatrix * vertex;
}"""
VERTEX_SHADER_SOURCE = """attribute vec4 vertex;
attribute vec3 normal;
varying vec3 vert;
varying vec3 vertNormal;
uniform mat4 projMatrix;
uniform mat4 mvMatrix;
uniform mat3 normalMatrix;
void main() {
vert = vertex.xyz;
vertNormal = normalMatrix * normal;
gl_Position = projMatrix * mvMatrix * vertex;
}"""
class GLWidget(QOpenGLWidget, QOpenGLFunctions):
x_rotation_changed = Signal(int)
y_rotation_changed = Signal(int)
z_rotation_changed = Signal(int)
_transparent = False
def __init__(self, parent=None):
QOpenGLWidget.__init__(self, parent)
QOpenGLFunctions.__init__(self)
self._core = QSurfaceFormat.defaultFormat().profile() == QSurfaceFormat.CoreProfile
self._x_rot = 0
self._y_rot = 0
self._z_rot = 0
self._last_pos = QPointF()
self.logo = Logo()
self.vao = QOpenGLVertexArrayObject()
self._logo_vbo = QOpenGLBuffer()
self.program = QOpenGLShaderProgram()
self._proj_matrix_loc = 0
self._mv_matrix_loc = 0
self._normal_matrix_loc = 0
self._light_pos_loc = 0
self.proj = QMatrix4x4()
self.camera = QMatrix4x4()
self.world = QMatrix4x4()
if self._transparent:
fmt = self.format()
fmt.setAlphaBufferSize(8)
self.setFormat(fmt)
@staticmethod
def set_transparent(t):
GLWidget._transparent = t
@staticmethod
def is_transparent():
return GLWidget._transparent
def x_rotation(self):
return self._x_rot
def y_rotation(self):
return self._y_rot
def z_rotation(self):
return self._z_rot
def minimumSizeHint(self):
return QSize(50, 50)
def sizeHint(self):
return QSize(400, 400)
def normalize_angle(self, angle):
while angle < 0:
angle += 360 * 16
while angle > 360 * 16:
angle -= 360 * 16
return angle
@Slot(int)
def set_xrotation(self, angle):
angle = self.normalize_angle(angle)
if angle != self._x_rot:
self._x_rot = angle
self.x_rotation_changed.emit(angle)
self.update()
@Slot(int)
def set_yrotation(self, angle):
angle = self.normalize_angle(angle)
if angle != self._y_rot:
self._y_rot = angle
self.y_rotation_changed.emit(angle)
self.update()
@Slot(int)
def set_zrotation(self, angle):
angle = self.normalize_angle(angle)
if angle != self._z_rot:
self._z_rot = angle
self.z_rotation_changed.emit(angle)
self.update()
@Slot()
def cleanup(self):
if self.program:
self.makeCurrent()
self._logo_vbo.destroy()
del self.program
self.program = None
self.doneCurrent()
def initializeGL(self):
self.initializeOpenGLFunctions()
self.glClearColor(0, 0, 0, 0 if self._transparent else 1)
self.program = QOpenGLShaderProgram()
if self._core:
self._vertex_shader = VERTEX_SHADER_SOURCE_CORE
self._fragment_shader = FRAGMENT_SHADER_SOURCE_CORE
else:
self._vertex_shader = VERTEX_SHADER_SOURCE
self._fragment_shader = FRAGMENT_SHADER_SOURCE
self.program.addShaderFromSourceCode(QOpenGLShader.Vertex,
self._vertex_shader)
self.program.addShaderFromSourceCode(QOpenGLShader.Fragment,
self._fragment_shader)
self.program.bindAttributeLocation("vertex", 0)
self.program.bindAttributeLocation("normal", 1)
self.program.link()
self.program.bind()
self._proj_matrix_loc = self.program.uniformLocation("projMatrix")
self._mv_matrix_loc = self.program.uniformLocation("mvMatrix")
self._normal_matrix_loc = self.program.uniformLocation("normalMatrix")
self._light_pos_loc = self.program.uniformLocation("lightPos")
self.vao.create()
with QOpenGLVertexArrayObject.Binder(self.vao):
self._logo_vbo.create()
self._logo_vbo.bind()
float_size = ctypes.sizeof(ctypes.c_float)
self._logo_vbo.allocate(self.logo.const_data(),
self.logo.count() * float_size)
self.setup_vertex_attribs()
self.camera.setToIdentity()
self.camera.translate(0, 0, -1)
self.program.setUniformValue(self._light_pos_loc,
QVector3D(0, 0, 70))
self.program.release()
def setup_vertex_attribs(self):
self._logo_vbo.bind()
f = QOpenGLContext.currentContext().functions()
f.glEnableVertexAttribArray(0)
f.glEnableVertexAttribArray(1)
float_size = ctypes.sizeof(ctypes.c_float)
null = VoidPtr(0)
pointer = VoidPtr(3 * float_size)
f.glVertexAttribPointer(0, 3, int(GL.GL_FLOAT), int(GL.GL_FALSE),
6 * float_size, null)
f.glVertexAttribPointer(1, 3, int(GL.GL_FLOAT), int(GL.GL_FALSE),
6 * float_size, pointer)
self._logo_vbo.release()
def paintGL(self):
self.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT)
self.glEnable(GL.GL_DEPTH_TEST)
self.glEnable(GL.GL_CULL_FACE)
self.world.setToIdentity()
self.world.rotate(180 - (self._x_rot / 16), 1, 0, 0)
self.world.rotate(self._y_rot / 16, 0, 1, 0)
self.world.rotate(self._z_rot / 16, 0, 0, 1)
with QOpenGLVertexArrayObject.Binder(self.vao):
self.program.bind()
self.program.setUniformValue(self._proj_matrix_loc, self.proj)
self.program.setUniformValue(self._mv_matrix_loc,
self.camera * self.world)
normal_matrix = self.world.normalMatrix()
self.program.setUniformValue(self._normal_matrix_loc, normal_matrix)
self.glDrawArrays(GL.GL_TRIANGLES, 0, self.logo.vertex_count())
self.program.release()
def resizeGL(self, width, height):
self.proj.setToIdentity()
self.proj.perspective(45, width / height, 0.01, 100)
def hideEvent(self, event):
self.cleanup()
super().hideEvent(event)
def mousePressEvent(self, event):
self._last_pos = event.position()
def mouseMoveEvent(self, event):
pos = event.position()
dx = pos.x() - self._last_pos.x()
dy = pos.y() - self._last_pos.y()
if event.buttons() & Qt.LeftButton:
self.set_xrotation(self._x_rot + 8 * dy)
self.set_yrotation(self._y_rot + 8 * dx)
elif event.buttons() & Qt.RightButton:
self.set_xrotation(self._x_rot + 8 * dy)
self.set_zrotation(self._z_rot + 8 * dx)
self._last_pos = pos
# Copyright (C) 2023 The Qt Company Ltd.
# Copyright (C) 2013 Riverbank Computing Limited.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
import math
from PySide6.QtGui import (QVector3D, QVector3DList)
class Logo():
def __init__(self):
self.m_data = QVector3DList()
self.m_data.reserve(5000)
x1 = +0.06
y1 = -0.14
x2 = +0.14
y2 = -0.06
x3 = +0.08
y3 = +0.00
x4 = +0.30
y4 = +0.22
self.quad(x1, y1, x2, y2, y2, x2, y1, x1)
self.quad(x3, y3, x4, y4, y4, x4, y3, x3)
self.extrude(x1, y1, x2, y2)
self.extrude(x2, y2, y2, x2)
self.extrude(y2, x2, y1, x1)
self.extrude(y1, x1, x1, y1)
self.extrude(x3, y3, x4, y4)
self.extrude(x4, y4, y4, x4)
self.extrude(y4, x4, y3, x3)
NUM_SECTORS = 100
for i in range(NUM_SECTORS):
angle = (i * 2 * math.pi) / NUM_SECTORS
x5 = 0.30 * math.sin(angle)
y5 = 0.30 * math.cos(angle)
x6 = 0.20 * math.sin(angle)
y6 = 0.20 * math.cos(angle)
angle = ((i + 1) * 2 * math.pi) / NUM_SECTORS
x7 = 0.20 * math.sin(angle)
y7 = 0.20 * math.cos(angle)
x8 = 0.30 * math.sin(angle)
y8 = 0.30 * math.cos(angle)
self.quad(x5, y5, x6, y6, x7, y7, x8, y8)
self.extrude(x6, y6, x7, y7)
self.extrude(x8, y8, x5, y5)
def const_data(self):
return self.m_data.constData()
def count(self):
return len(self.m_data) * 3
def vertex_count(self):
return self.count() / 6
def quad(self, x1, y1, x2, y2, x3, y3, x4, y4):
n = QVector3D.normal(QVector3D(x4 - x1, y4 - y1, 0),
QVector3D(x2 - x1, y2 - y1, 0))
self.add(QVector3D(x1, y1, -0.05), n)
self.add(QVector3D(x4, y4, -0.05), n)
self.add(QVector3D(x2, y2, -0.05), n)
self.add(QVector3D(x3, y3, -0.05), n)
self.add(QVector3D(x2, y2, -0.05), n)
self.add(QVector3D(x4, y4, -0.05), n)
n = QVector3D.normal(QVector3D(x1 - x4, y1 - y4, 0),
QVector3D(x2 - x4, y2 - y4, 0))
self.add(QVector3D(x4, y4, 0.05), n)
self.add(QVector3D(x1, y1, 0.05), n)
self.add(QVector3D(x2, y2, 0.05), n)
self.add(QVector3D(x2, y2, 0.05), n)
self.add(QVector3D(x3, y3, 0.05), n)
self.add(QVector3D(x4, y4, 0.05), n)
def extrude(self, x1, y1, x2, y2):
n = QVector3D.normal(QVector3D(0, 0, -0.1),
QVector3D(x2 - x1, y2 - y1, 0))
self.add(QVector3D(x1, y1, 0.05), n)
self.add(QVector3D(x1, y1, -0.05), n)
self.add(QVector3D(x2, y2, 0.05), n)
self.add(QVector3D(x2, y2, -0.05), n)
self.add(QVector3D(x2, y2, 0.05), n)
self.add(QVector3D(x1, y1, -0.05), n)
def add(self, v, n):
self.m_data.append(v)
self.m_data.append(n)
# Copyright (C) 2023 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from PySide6.QtCore import Slot, Qt
from PySide6.QtGui import QKeySequence
from PySide6.QtWidgets import QMainWindow, QMessageBox
from window import Window
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
menuWindow = self.menuBar().addMenu("Window")
menuWindow.addAction("Add new", QKeySequence(Qt.CTRL | Qt.Key_N),
self.onAddNew)
menuWindow.addAction("Quit", QKeySequence(Qt.CTRL | Qt.Key_Q),
qApp.closeAllWindows) # noqa: F821
self.onAddNew()
@Slot()
def onAddNew(self):
if not self.centralWidget():
self.setCentralWidget(Window(self))
else:
QMessageBox.information(self, "Cannot Add Window()",
"Already occupied. Undock first.")
# Copyright (C) 2023 The Qt Company Ltd.
# Copyright (C) 2013 Riverbank Computing Limited.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from PySide6.QtCore import Slot, Qt
from PySide6.QtWidgets import (QHBoxLayout, QMainWindow,
QMessageBox, QPushButton, QSlider,
QVBoxLayout, QWidget)
from glwidget import GLWidget
def _main_window():
for t in qApp.topLevelWidgets(): # noqa: F821
if isinstance(t, QMainWindow):
return t
return None
class Window(QWidget):
instances = [] # Keep references when undocked
def __init__(self, parent=None):
super().__init__(parent)
self.instances.append(self)
self._gl_widget = GLWidget()
self._x_slider = self.create_slider()
self._x_slider.valueChanged.connect(self._gl_widget.set_xrotation)
self._gl_widget.x_rotation_changed.connect(self._x_slider.setValue)
self._y_slider = self.create_slider()
self._y_slider.valueChanged.connect(self._gl_widget.set_yrotation)
self._gl_widget.y_rotation_changed.connect(self._y_slider.setValue)
self._z_slider = self.create_slider()
self._z_slider.valueChanged.connect(self._gl_widget.set_zrotation)
self._gl_widget.z_rotation_changed.connect(self._z_slider.setValue)
mainLayout = QVBoxLayout(self)
w = QWidget()
container = QHBoxLayout(w)
container.addWidget(self._gl_widget)
container.addWidget(self._x_slider)
container.addWidget(self._y_slider)
container.addWidget(self._z_slider)
mainLayout.addWidget(w)
self._dock_btn = QPushButton("Undock")
self._dock_btn.clicked.connect(self.dock_undock)
mainLayout.addWidget(self._dock_btn)
self._x_slider.setValue(15 * 16)
self._y_slider.setValue(345 * 16)
self._z_slider.setValue(0 * 16)
self.setWindowTitle(self.tr("Hello GL"))
def create_slider(self):
slider = QSlider(Qt.Vertical)
slider.setRange(0, 360 * 16)
slider.setSingleStep(16)
slider.setPageStep(15 * 16)
slider.setTickInterval(15 * 16)
slider.setTickPosition(QSlider.TicksRight)
return slider
def closeEvent(self, event):
self.instances.remove(self)
event.accept()
def keyPressEvent(self, event):
if self.isWindow() and event.key() == Qt.Key_Escape:
self.close()
else:
super().keyPressEvent(event)
@Slot()
def dock_undock(self):
if self.parent():
self.undock()
else:
self.dock()
def dock(self):
mainWindow = _main_window()
if not mainWindow or not mainWindow.isVisible():
QMessageBox.information(self, "Cannot Dock",
"Main window already closed")
return
if mainWindow.centralWidget():
QMessageBox.information(self, "Cannot Dock",
"Main window already occupied")
return
self.setAttribute(Qt.WA_DeleteOnClose, False)
self._dock_btn.setText("Undock")
mainWindow.setCentralWidget(self)
def undock(self):
self.setParent(None)
self.setAttribute(Qt.WA_DeleteOnClose)
geometry = self.screen().availableGeometry()
x = geometry.x() + (geometry.width() - self.width()) / 2
y = geometry.y() + (geometry.height() - self.height()) / 2
self.move(x, y)
self._dock_btn.setText("Dock")
self.show()