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我想使用Qt和PyOpenGL做一些實時繪圖並學習一些關於OpenGL的知識，但是即使讓我的初始測試數據出現，也遇到了麻煩。使用PyOpenGL繪圖時的麻煩
這個想法是將x座標和y座標存儲在不同的緩衝區中，因爲x座標幾乎不會改變，而y座標將幾乎改變每個渲染。不幸的是，讓他們進入不同的緩衝區會給我帶來問題。
現在我沒有錯誤，沒有任何顯示，所以我不知道該去哪裏。
這裏是我迄今爲止的繪圖類：
class GLWidget(QtOpenGL.QGLWidget):
def __init__(self, parent=None):
self.parent = parent
QtOpenGL.QGLWidget.__init__(self, parent)
self.current_position = 0
def initializeGL(self):
self.initGeometry()
self.vertex_code = """
#version 120
attribute vec4 color;
attribute float x_position;
attribute float y_position;
varying vec4 v_color;
void main()
{
gl_Position = vec4(x_position, y_position, 0.0, 1.0);
v_color = color;
} """
self.fragment_code = """
#version 120
varying vec4 v_color;
void main()
{
//gl_FragColor = v_color;
gl_FragColor = vec4(1,1,1,1);
} """
## Build and activate program
# Request program and shader slots from GPU
self.program = GL.glCreateProgram()
self.vertex = GL.glCreateShader(GL.GL_VERTEX_SHADER)
self.fragment = GL.glCreateShader(GL.GL_FRAGMENT_SHADER)
# Set shaders source
GL.glShaderSource(self.vertex, self.vertex_code)
GL.glShaderSource(self.fragment, self.fragment_code)
# Compile shaders
GL.glCompileShader(self.vertex)
GL.glCompileShader(self.fragment)
# Attach shader objects to the program
GL.glAttachShader(self.program, self.vertex)
GL.glAttachShader(self.program, self.fragment)
# Build program
GL.glLinkProgram(self.program)
# Get rid of shaders (not needed anymore)
GL.glDetachShader(self.program, self.vertex)
GL.glDetachShader(self.program, self.fragment)
# Make program the default program
GL.glUseProgram(self.program)
# Create array object
self.vao = GL.glGenVertexArrays(1)
GL.glBindVertexArray(self.vao)
# Request buffer slot from GPU
self.x_data_buffer = GL.glGenBuffers(1)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.x_data_buffer)
GL.glBufferData(GL.GL_ARRAY_BUFFER, ArrayDatatype.arrayByteCount(self.x), self.x, GL.GL_DYNAMIC_DRAW)
self.y_data_buffer = GL.glGenBuffers(1)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.y_data_buffer)
GL.glBufferData(GL.GL_ARRAY_BUFFER, ArrayDatatype.arrayByteCount(self.y), self.y, GL.GL_DYNAMIC_DRAW)
## Bind attributes
#self.stride = self.x.strides[0]
#self.offset = ctypes.c_void_p(0)
self.loc = GL.glGetAttribLocation(self.program, "x_position".encode('utf-8'))
GL.glEnableVertexAttribArray(self.loc)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.x_data_buffer)
GL.glVertexAttribPointer(self.loc, 1, GL.GL_FLOAT, GL.GL_FALSE, 0, 0)
#self.stride = self.y.strides[0]
#self.offset = ctypes.c_void_p(0)
self.loc = GL.glGetAttribLocation(self.program, "y_position".encode('utf-8'))
GL.glEnableVertexAttribArray(self.loc)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.y_data_buffer)
GL.glVertexAttribPointer(self.loc, 1, GL.GL_FLOAT, GL.GL_FALSE, 0, 0)
def resizeGL(self, width, height):
if height == 0: height = 1
GL.glViewport(0, 0, width, height)
GL.glMatrixMode(GL.GL_PROJECTION)
GL.glLoadIdentity()
aspect = width/float(height)
GLU.gluPerspective(45.0, aspect, 1.0, 100.0)
GL.glMatrixMode(GL.GL_MODELVIEW)
def paintGL(self):
GL.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT)
GL.glDrawArrays(GL.GL_LINE_STRIP, 0, self.bins)
def initGeometry(self):
self.bins = 1000
self.x = np.linspace(-0.5,0.5,self.bins)
self.y = np.array([np.sin(val*2*np.pi) for val in self.x])
self.color = np.array([(1,1,1,1) for x in np.arange(self.bins)])
def addPoint(self, point):
#print('ADD POINT')
self.y[self.current_position] = point
if self.current_position < self.bins-1:
self.current_position += 1
else:
self.current_position = 0
return True
def render(self):
#print('RENDER')
self.updateGL()
return True
我也把程序的完整工作版本瀏覽：
import sys
from PyQt5.QtWidgets import QDesktopWidget, QMainWindow, QWidget, QAction, qApp, QApplication, QHBoxLayout, QVBoxLayout, QPushButton
from PyQt5.QtCore import QTimer
from PyQt5.QtGui import QIcon
from PyQt5 import QtOpenGL
from OpenGL import GL
from OpenGL import GLU
from OpenGL.arrays.arraydatatype import ArrayDatatype
import ctypes
import numpy as np
from threading import Timer, Thread, Event
class OxySensor(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
self.initActions()
self.initMenuBar()
self.initRenderTimer()
self.start()
def initUI(self):
self.resize(800,600)
self.center()
self.setWindowTitle('OxySensor')
okButton = QPushButton("OK")
cancelButton = QPushButton("Cancel")
hbox = QHBoxLayout()
hbox.addStretch(1)
hbox.addWidget(okButton)
hbox.addWidget(cancelButton)
vbox = QVBoxLayout()
#vbox.addStretch(1)
self.gl_widget = GLWidget()
vbox.addWidget(self.gl_widget)
vbox.addLayout(hbox)
mainWidget = QWidget(self)
mainWidget.setLayout(vbox)
self.setCentralWidget(mainWidget)
self.show()
def initActions(self):
self.exitAction = QAction(QIcon('images/close20.png'), '&Exit', self)
self.exitAction.setShortcut('Ctrl+W')
self.exitAction.setStatusTip('Exit application')
self.exitAction.triggered.connect(self.onExit)
def initMenuBar(self):
menubar = self.menuBar()
fileMenu = menubar.addMenu('&File')
fileMenu.addAction(self.exitAction)
return True
def initRenderTimer(self):
self.timer = QTimer()
self.timer.timeout.connect(self.gl_widget.render)
self.timer.start(100)
return True
def start(self):
self.stop_flag = Event()
self.thread = SerialPort(self.onTimerExpired, self.stop_flag)
self.thread.start()
self.statusBar().showMessage('Ready')
def center(self):
qr = self.frameGeometry()
cp = QDesktopWidget().availableGeometry().center()
qr.moveCenter(cp)
self.move(qr.topLeft())
return True
def onTimerExpired(self):
data = np.random.uniform(-1,1)
self.gl_widget.addPoint(data)
return True
def onExit(self):
self.close()
return None
def closeEvent(self,event):
self.stop_flag.set()
event.accept()
return None
class GLWidget(QtOpenGL.QGLWidget):
def __init__(self, parent=None):
self.parent = parent
QtOpenGL.QGLWidget.__init__(self, parent)
self.yRotDeg = 0.0
self.current_position = 0
def initializeGL(self):
self.initGeometry()
self.vertex_code = """
#version 120
attribute vec4 color;
attribute float x_position;
attribute float y_position;
varying vec4 v_color;
void main()
{
gl_Position = vec4(x_position, y_position, 0.0, 1.0);
v_color = color;
} """
self.fragment_code = """
#version 120
varying vec4 v_color;
void main()
{
//gl_FragColor = v_color;
gl_FragColor = vec4(1,1,1,1);
} """
## Build and activate program
# Request program and shader slots from GPU
self.program = GL.glCreateProgram()
self.vertex = GL.glCreateShader(GL.GL_VERTEX_SHADER)
self.fragment = GL.glCreateShader(GL.GL_FRAGMENT_SHADER)
# Set shaders source
GL.glShaderSource(self.vertex, self.vertex_code)
GL.glShaderSource(self.fragment, self.fragment_code)
# Compile shaders
GL.glCompileShader(self.vertex)
GL.glCompileShader(self.fragment)
# Attach shader objects to the program
GL.glAttachShader(self.program, self.vertex)
GL.glAttachShader(self.program, self.fragment)
# Build program
GL.glLinkProgram(self.program)
# Get rid of shaders (not needed anymore)
GL.glDetachShader(self.program, self.vertex)
GL.glDetachShader(self.program, self.fragment)
# Make program the default program
GL.glUseProgram(self.program)
# Create array object
self.vao = GL.glGenVertexArrays(1)
GL.glBindVertexArray(self.vao)
# Request buffer slot from GPU
self.x_data_buffer = GL.glGenBuffers(1)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.x_data_buffer)
GL.glBufferData(GL.GL_ARRAY_BUFFER, ArrayDatatype.arrayByteCount(self.x), self.x, GL.GL_DYNAMIC_DRAW)
self.y_data_buffer = GL.glGenBuffers(1)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.y_data_buffer)
GL.glBufferData(GL.GL_ARRAY_BUFFER, ArrayDatatype.arrayByteCount(self.y), self.y, GL.GL_DYNAMIC_DRAW)
## Bind attributes
#self.stride = self.x.strides[0]
#self.offset = ctypes.c_void_p(0)
self.loc = GL.glGetAttribLocation(self.program, "x_position".encode('utf-8'))
GL.glEnableVertexAttribArray(self.loc)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.x_data_buffer)
GL.glVertexAttribPointer(self.loc, 1, GL.GL_FLOAT, GL.GL_FALSE, 0, 0)
#self.stride = self.y.strides[0]
#self.offset = ctypes.c_void_p(0)
self.loc = GL.glGetAttribLocation(self.program, "y_position".encode('utf-8'))
GL.glEnableVertexAttribArray(self.loc)
GL.glBindBuffer(GL.GL_ARRAY_BUFFER, self.y_data_buffer)
GL.glVertexAttribPointer(self.loc, 1, GL.GL_FLOAT, GL.GL_FALSE, 0, 0)
def resizeGL(self, width, height):
if height == 0: height = 1
GL.glViewport(0, 0, width, height)
GL.glMatrixMode(GL.GL_PROJECTION)
GL.glLoadIdentity()
aspect = width/float(height)
GLU.gluPerspective(45.0, aspect, 1.0, 100.0)
GL.glMatrixMode(GL.GL_MODELVIEW)
def paintGL(self):
GL.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT)
GL.glDrawArrays(GL.GL_LINE_STRIP, 0, self.bins)
def initGeometry(self):
self.bins = 1000
self.x = np.linspace(-0.5,0.5,self.bins)
self.y = np.array([np.sin(val*2*np.pi) for val in self.x])
self.color = np.array([(1,1,1,1) for x in np.arange(self.bins)])
def addPoint(self, point):
#print('ADD POINT')
self.y[self.current_position] = point
if self.current_position < self.bins-1:
self.current_position += 1
else:
self.current_position = 0
return True
def render(self):
#print('RENDER')
self.updateGL()
return True
class SerialPort(Thread):
def __init__(self, callback, event):
Thread.__init__(self)
self.callback = callback
self.stopped = event
return None
def SetInterval(self, time_in_seconds):
self.delay_period = time_in_seconds
return True
def run(self):
while not self.stopped.wait(0.1):
self.callback()
return True
if __name__ == '__main__':
app = QApplication(sys.argv)
oxy_sensor = OxySensor()
sys.exit(app.exec_())
'updateGL（）'方法在哪裏？到目前爲止發佈的代碼從未實際更新VBO內容後初始創建它們。 – derhass
'updateGL（）'在'render（）'方法中 – user2027202827
嗯，我可以看到它是_called_那裏。也許我誤解了一些東西，這個'updateGL'是pthon OpenGL小部件的一些方法。如果是這樣，那麼我的評論甚至應用更多：然後你從未實際更新那些VBO（我認爲這是在'updateGL'中完成的）。 – derhass