如何在 PyQt5 QOpenGLWidget 中对球体进行纹理处理
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【中文标题】如何在 PyQt5 QOpenGLWidget 中对球体进行纹理处理【英文标题】：How to texture a sphere in PyQt5 QOpenGLWidget 【发布时间】：2020-11-27 05:48:20 【问题描述】：我正在尝试在我使用 PyQt5 制作的程序中显示世界地图。对于到目前为止的渲染内容，这是我拥有的（主要是借用的）代码：
import sys
import math
import numpy as np
from PIL import Image, ImageQt
from PyQt5.QtCore import pyqtSignal, QPoint, QSize, Qt
from PyQt5.QtGui import QColor, QOpenGLVersionProfile
from PyQt5.QtWidgets import (QApplication, QHBoxLayout, QOpenGLWidget, QWidget)
class Window(QWidget):
def __init__(self):
super(Window, self).__init__()
self.glWidget = GLWidget()
mainLayout = QHBoxLayout()
mainLayout.addWidget(self.glWidget)
self.setLayout(mainLayout)
self.img = Image.open("BWTopo.png")
self.mapWidth, self.mapHeight = self.img.size
pgImData = np.asarray(self.img)
self.inputMapFile = np.flipud(pgImData)
self.setWindowTitle("SPHERE")
class GLWidget(QOpenGLWidget):
def __init__(self, parent=None):
super(GLWidget, self).__init__(parent)
self.object = 0
self.xRot = 0
self.yRot = 0
self.zRot = 0
self.lastPos = QPoint()
self.main = QColor.fromCmykF(0.40, 0.0, 1.0, 0.0)
self.clear = QColor.fromCmykF(0.39, 0.39, 0.0, 0.0)
def sizeHint(self):
return QSize(400, 400)
def setXRotation(self, angle):
angle = self.normalizeAngle(angle)
if angle != self.xRot:
self.xRot = angle
self.update()
def setYRotation(self, angle):
angle = self.normalizeAngle(angle)
if angle != self.yRot:
self.yRot = angle
self.update()
def setZRotation(self, angle):
angle = self.normalizeAngle(angle)
if angle != self.zRot:
self.zRot = angle
self.update()
def initializeGL(self):
version_profile = QOpenGLVersionProfile()
version_profile.setVersion(2, 0)
self.gl = self.context().versionFunctions(version_profile)
self.gl.initializeOpenGLFunctions()
self.setClearColor(self.clear.darker())
self.object = self.makeObject()
self.gl.glShadeModel(self.gl.GL_FLAT)
self.gl.glEnable(self.gl.GL_DEPTH_TEST)
self.gl.glEnable(self.gl.GL_CULL_FACE)
self.gl.glEnable(self.gl.GL_LIGHTING)
self.gl.glLightModelfv(self.gl.GL_LIGHT_MODEL_AMBIENT, [0.9, 0.9, 0.9, 1.0])
self.gl.glEnable(self.gl.GL_COLOR_MATERIAL)
self.gl.glColorMaterial(self.gl.GL_FRONT, self.gl.GL_AMBIENT_AND_DIFFUSE)
def paintGL(self):
self.gl.glClear(self.gl.GL_COLOR_BUFFER_BIT | self.gl.GL_DEPTH_BUFFER_BIT)
self.gl.glLoadIdentity()
self.gl.glTranslated(0.0, 0.0, -10.0)
self.gl.glRotated(self.xRot / 16.0, 1.0, 0.0, 0.0)
self.gl.glRotated(self.yRot / 16.0, 0.0, 1.0, 0.0)
self.gl.glRotated(self.zRot / 16.0, 0.0, 0.0, 1.0)
self.gl.glCallList(self.object)
def resizeGL(self, width, height):
side = min(width, height)
if side < 0:
return
self.gl.glViewport((width - side) // 2, (height - side) // 2, side,
side)
self.gl.glMatrixMode(self.gl.GL_PROJECTION)
self.gl.glLoadIdentity()
self.gl.glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0)
self.gl.glMatrixMode(self.gl.GL_MODELVIEW)
def mousePressEvent(self, event):
self.lastPos = event.pos()
def mouseMoveEvent(self, event):
dx = event.x() - self.lastPos.x()
dy = event.y() - self.lastPos.y()
if event.buttons() & Qt.LeftButton:
self.setXRotation(self.xRot + 8 * dy)
self.setYRotation(self.yRot + 8 * dx)
elif event.buttons() & Qt.RightButton:
self.setXRotation(self.xRot + 8 * dy)
self.setZRotation(self.zRot + 8 * dx)
self.lastPos = event.pos()
def makeObject(self):
genList = self.gl.glGenLists(1)
self.gl.glNewList(genList, self.gl.GL_COMPILE)
self.gl.glBegin(self.gl.GL_TRIANGLES)
UResolution = 18
VResolution = 36
r = 0.3
startU = 0
startV = 0
endU = math.pi * 2
endV = math.pi
stepU = (endU-startU)/UResolution # step size between U-points on the grid
stepV = (endV-startV)/VResolution # step size between V-points on the grid
for i in range(UResolution): # U-points
for j in range(VResolution): # V-points
u = i*stepU+startU
v = j*stepV+startV
un = endU if (i+1==UResolution) else (i+1)*stepU+startU
vn = endV if (j+1==VResolution) else (j+1)*stepV+startV
p0 = [ math.cos(u)*math.sin(v)*r, math.cos(v)*r, math.sin(u)*math.sin(v)*r ]
p1 = [ math.cos(u)*math.sin(vn)*r, math.cos(vn)*r, math.sin(u)*math.sin(vn)*r ]
p2 = [ math.cos(un)*math.sin(v)*r, math.cos(v)*r, math.sin(un)*math.sin(v)*r ]
p3 = [ math.cos(un)*math.sin(vn)*r, math.cos(vn)*r, math.sin(un)*math.sin(vn)*r ]
# Output the first triangle of this grid square
self.gl.glVertex3f(p0[0],p0[1],p0[2])
self.gl.glVertex3f(p2[0],p2[1],p2[2])
self.gl.glVertex3f(p1[0],p1[1],p1[2])
# Output the other triangle of this grid square
self.gl.glVertex3f(p3[0],p3[1],p3[2])
self.gl.glVertex3f(p1[0],p1[1],p1[2])
self.gl.glVertex3f(p2[0],p2[1],p2[2])
self.gl.glEnd()
self.gl.glEndList()
return genList
def normalizeAngle(self, angle):
while angle < 0:
angle += 360 * 16
while angle > 360 * 16:
angle -= 360 * 16
return angle
def setClearColor(self, c):
self.gl.glClearColor(c.redF(), c.greenF(), c.blueF(), c.alphaF())
def setColor(self, c):
self.gl.glColor4f(c.redF(), c.greenF(), c.blueF(), c.alphaF())
if __name__ == '__main__':
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
它在窗口中创建一个无阴影的球体。我想将从“BWTopo”加载的图像作为等角投影图应用到球体上。我该怎么做呢？
【问题讨论】：
【参考方案1】：你必须创建一个纹理对象：
self.gl.glActiveTexture(self.gl.GL_TEXTURE0)
self.text_obj = self.gl.glGenTextures(1)
self.gl.glBindTexture(self.gl.GL_TEXTURE_2D, self.text_obj)
self.gl.glPixelStorei(self.gl.GL_UNPACK_ALIGNMENT, 1)
self.gl.glTexImage2D(self.gl.GL_TEXTURE_2D, 0, self.gl.GL_RGB, self.mapWidth, self.mapHeight, 0, self.gl.GL_RGB, self.gl.GL_UNSIGNED_BYTE, self.inputMapFile.tobytes())
self.gl.glPixelStorei(self.gl.GL_UNPACK_ALIGNMENT, 4)
self.gl.glTexParameterf(self.gl.GL_TEXTURE_2D, self.gl.GL_TEXTURE_MAG_FILTER, self.gl.GL_LINEAR)
self.gl.glTexParameterf(self.gl.GL_TEXTURE_2D, self.gl.GL_TEXTURE_MIN_FILTER, self.gl.GL_LINEAR)
您需要在 [0, 1] 范围内创建纹理坐标：
t0 = [i/UResolution, 1-j/VResolution]
t1 = [i/UResolution, 1-(j+1)/VResolution]
t2 = [(i+1)/UResolution, 1-j/VResolution]
t3 = [(i+1)/UResolution, 1-(j+1)/VResolution]
# Output the first triangle of this grid square
self.gl.glTexCoord2f(*t0)
self.gl.glVertex3f(*p0)
self.gl.glTexCoord2f(*t2)
self.gl.glVertex3f(*p2)
self.gl.glTexCoord2f(*t1)
self.gl.glVertex3f(*p1)
# Output the other triangle of this grid square
self.gl.glTexCoord2f(*t3)
self.gl.glVertex3f(*p3)
self.gl.glTexCoord2f(*t1)
self.gl.glVertex3f(*p1)
self.gl.glTexCoord2f(*t2)
self.gl.glVertex3f(*p2)
二维纹理必须开启，见glEnable，并且在绘制网格之前需要绑定纹理对象：
self.gl.glEnable(self.gl.GL_TEXTURE_2D)
self.gl.glBindTexture(self.gl.GL_TEXTURE_2D, self.text_obj)
self.gl.glColor3f(1, 1, 1)
self.gl.glCallList(self.object)
完整示例：
import sys
import math
import numpy as np
from PIL import Image, ImageQt
from PyQt5.QtCore import pyqtSignal, QPoint, QSize, Qt
from PyQt5.QtGui import QColor, QOpenGLVersionProfile
from PyQt5.QtWidgets import (QApplication, QHBoxLayout, QOpenGLWidget, QWidget)
class Window(QWidget):
def __init__(self):
super(Window, self).__init__()
self.glWidget = GLWidget()
mainLayout = QHBoxLayout()
mainLayout.addWidget(self.glWidget)
self.setLayout(mainLayout)
self.setWindowTitle("SPHERE")
class GLWidget(QOpenGLWidget):
def __init__(self, parent=None):
super(GLWidget, self).__init__(parent)
self.object = 0
self.xRot = 0
self.yRot = 0
self.zRot = 0
self.lastPos = QPoint()
self.main = QColor.fromCmykF(0.40, 0.0, 1.0, 0.0)
self.clear = QColor.fromCmykF(0.39, 0.39, 0.0, 0.0)
self.img = Image.open("BWTopo.png")
#self.img = Image.open("worldmap1.bmp")
self.mapWidth, self.mapHeight = self.img.size
pgImData = np.asarray(self.img)
self.inputMapFile = np.flipud(pgImData)
def sizeHint(self):
return QSize(400, 400)
def setXRotation(self, angle):
angle = self.normalizeAngle(angle)
if angle != self.xRot:
self.xRot = angle
self.update()
def setYRotation(self, angle):
angle = self.normalizeAngle(angle)
if angle != self.yRot:
self.yRot = angle
self.update()
def setZRotation(self, angle):
angle = self.normalizeAngle(angle)
if angle != self.zRot:
self.zRot = angle
self.update()
def initializeGL(self):
version_profile = QOpenGLVersionProfile()
version_profile.setVersion(2, 0)
self.gl = self.context().versionFunctions(version_profile)
self.gl.initializeOpenGLFunctions()
self.setClearColor(self.clear.darker())
self.object = self.makeObject()
self.gl.glShadeModel(self.gl.GL_SMOOTH)
self.gl.glEnable(self.gl.GL_DEPTH_TEST)
self.gl.glEnable(self.gl.GL_CULL_FACE)
self.gl.glEnable(self.gl.GL_LIGHTING)
self.gl.glLightModelfv(self.gl.GL_LIGHT_MODEL_AMBIENT, [0.9, 0.9, 0.9, 1.0])
self.gl.glEnable(self.gl.GL_COLOR_MATERIAL)
self.gl.glColorMaterial(self.gl.GL_FRONT, self.gl.GL_AMBIENT_AND_DIFFUSE)
self.gl.glActiveTexture(self.gl.GL_TEXTURE0)
self.text_obj = self.gl.glGenTextures(1)
self.gl.glBindTexture(self.gl.GL_TEXTURE_2D, self.text_obj)
self.gl.glPixelStorei(self.gl.GL_UNPACK_ALIGNMENT, 1)
self.gl.glTexImage2D(self.gl.GL_TEXTURE_2D, 0, self.gl.GL_RGB, self.mapWidth, self.mapHeight, 0, self.gl.GL_RGB, self.gl.GL_UNSIGNED_BYTE, self.inputMapFile.tobytes())
self.gl.glPixelStorei(self.gl.GL_UNPACK_ALIGNMENT, 4)
self.gl.glTexParameterf(self.gl.GL_TEXTURE_2D, self.gl.GL_TEXTURE_MAG_FILTER, self.gl.GL_LINEAR)
self.gl.glTexParameterf(self.gl.GL_TEXTURE_2D, self.gl.GL_TEXTURE_MIN_FILTER, self.gl.GL_LINEAR)
def paintGL(self):
self.gl.glClear(self.gl.GL_COLOR_BUFFER_BIT | self.gl.GL_DEPTH_BUFFER_BIT)
self.gl.glLoadIdentity()
self.gl.glTranslated(0.0, 0.0, -10.0)
self.gl.glRotated(self.xRot / 16.0, 1.0, 0.0, 0.0)
self.gl.glRotated(self.yRot / 16.0, 0.0, 1.0, 0.0)
self.gl.glRotated(self.zRot / 16.0, 0.0, 0.0, 1.0)
self.gl.glEnable(self.gl.GL_TEXTURE_2D)
self.gl.glBindTexture(self.gl.GL_TEXTURE_2D, self.text_obj)
self.gl.glColor3f(1, 1, 1)
self.gl.glCallList(self.object)
def resizeGL(self, width, height):
side = min(width, height)
if side < 0:
return
self.gl.glViewport((width - side) // 2, (height - side) // 2, side,
side)
self.gl.glMatrixMode(self.gl.GL_PROJECTION)
self.gl.glLoadIdentity()
self.gl.glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0)
self.gl.glMatrixMode(self.gl.GL_MODELVIEW)
def mousePressEvent(self, event):
self.lastPos = event.pos()
def mouseMoveEvent(self, event):
dx = event.x() - self.lastPos.x()
dy = event.y() - self.lastPos.y()
if event.buttons() & Qt.LeftButton:
self.setXRotation(self.xRot + 8 * dy)
self.setYRotation(self.yRot + 8 * dx)
elif event.buttons() & Qt.RightButton:
self.setXRotation(self.xRot + 8 * dy)
self.setZRotation(self.zRot + 8 * dx)
self.lastPos = event.pos()
def makeObject(self):
genList = self.gl.glGenLists(1)
self.gl.glNewList(genList, self.gl.GL_COMPILE)
self.gl.glBegin(self.gl.GL_TRIANGLES)
UResolution = 18
VResolution = 36
r = 0.3
startU = 0
startV = 0
endU = math.pi * 2
endV = math.pi
stepU = (endU-startU)/UResolution # step size between U-points on the grid
stepV = (endV-startV)/VResolution # step size between V-points on the grid
for i in range(UResolution): # U-points
for j in range(VResolution): # V-points
u = i*stepU+startU
v = j*stepV+startV
un = endU if (i+1==UResolution) else (i+1)*stepU+startU
vn = endV if (j+1==VResolution) else (j+1)*stepV+startV
p0 = [ math.cos(u)*math.sin(v)*r, math.cos(v)*r, math.sin(u)*math.sin(v)*r ]
p1 = [ math.cos(u)*math.sin(vn)*r, math.cos(vn)*r, math.sin(u)*math.sin(vn)*r ]
p2 = [ math.cos(un)*math.sin(v)*r, math.cos(v)*r, math.sin(un)*math.sin(v)*r ]
p3 = [ math.cos(un)*math.sin(vn)*r, math.cos(vn)*r, math.sin(un)*math.sin(vn)*r ]
t0 = [i/UResolution, 1-j/VResolution]
t1 = [i/UResolution, 1-(j+1)/VResolution]
t2 = [(i+1)/UResolution, 1-j/VResolution]
t3 = [(i+1)/UResolution, 1-(j+1)/VResolution]
# Output the first triangle of this grid square
self.gl.glTexCoord2f(*t0)
self.gl.glVertex3f(*p0)
self.gl.glTexCoord2f(*t2)
self.gl.glVertex3f(*p2)
self.gl.glTexCoord2f(*t1)
self.gl.glVertex3f(*p1)
# Output the other triangle of this grid square
self.gl.glTexCoord2f(*t3)
self.gl.glVertex3f(*p3)
self.gl.glTexCoord2f(*t1)
self.gl.glVertex3f(*p1)
self.gl.glTexCoord2f(*t2)
self.gl.glVertex3f(*p2)
self.gl.glEnd()
self.gl.glEndList()
return genList
def normalizeAngle(self, angle):
while angle < 0:
angle += 360 * 16
while angle > 360 * 16:
angle -= 360 * 16
return angle
def setClearColor(self, c):
self.gl.glClearColor(c.redF(), c.greenF(), c.blueF(), c.alphaF())
def setColor(self, c):
self.gl.glColor4f(c.redF(), c.greenF(), c.blueF(), c.alphaF())
if __name__ == '__main__':
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
【讨论】：
感谢您的回答！但是，当我使用您在程序中提供的代码时，它会完成而不显示任何内容。这是我的问题吗？ @Drickken 我已将完整、运行良好的示例添加到问题中。以上是关于如何在 PyQt5 QOpenGLWidget 中对球体进行纹理处理的主要内容，如果未能解决你的问题，请参考以下文章
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