Source code for pyqtgraph.opengl.GLViewWidget

from ..Qt import QtCore, QtGui, QtOpenGL, USE_PYQT5
from OpenGL.GL import *
import OpenGL.GL.framebufferobjects as glfbo
import numpy as np
from .. import Vector
from .. import functions as fn

##Vector = QtGui.QVector3D

ShareWidget = None

[docs]class GLViewWidget(QtOpenGL.QGLWidget): """ Basic widget for displaying 3D data - Rotation/scale controls - Axis/grid display - Export options """
[docs] def __init__(self, parent=None): global ShareWidget if ShareWidget is None: ## create a dummy widget to allow sharing objects (textures, shaders, etc) between views ShareWidget = QtOpenGL.QGLWidget() QtOpenGL.QGLWidget.__init__(self, parent, ShareWidget) self.setFocusPolicy(QtCore.Qt.ClickFocus) self.opts = { 'center': Vector(0,0,0), ## will always appear at the center of the widget 'distance': 10.0, ## distance of camera from center 'fov': 60, ## horizontal field of view in degrees 'elevation': 30, ## camera's angle of elevation in degrees 'azimuth': 45, ## camera's azimuthal angle in degrees ## (rotation around z-axis 0 points along x-axis) 'viewport': None, ## glViewport params; None == whole widget } self.setBackgroundColor('k') self.items = [] self.noRepeatKeys = [QtCore.Qt.Key_Right, QtCore.Qt.Key_Left, QtCore.Qt.Key_Up, QtCore.Qt.Key_Down, QtCore.Qt.Key_PageUp, QtCore.Qt.Key_PageDown] self.keysPressed = {} self.keyTimer = QtCore.QTimer() self.keyTimer.timeout.connect(self.evalKeyState) self.makeCurrent()
def addItem(self, item): self.items.append(item) if hasattr(item, 'initializeGL'): self.makeCurrent() try: item.initializeGL() except: self.checkOpenGLVersion('Error while adding item %s to GLViewWidget.' % str(item)) item._setView(self) #print "set view", item, self, item.view() self.update() def removeItem(self, item): self.items.remove(item) item._setView(None) self.update() def initializeGL(self): self.resizeGL(self.width(), self.height())
[docs] def setBackgroundColor(self, *args, **kwds): """ Set the background color of the widget. Accepts the same arguments as pg.mkColor() and pg.glColor(). """ self.opts['bgcolor'] = fn.glColor(*args, **kwds) self.update()
def getViewport(self): vp = self.opts['viewport'] if vp is None: return (0, 0, self.width(), self.height()) else: return vp def resizeGL(self, w, h): pass #glViewport(*self.getViewport()) #self.update() def setProjection(self, region=None): m = self.projectionMatrix(region) glMatrixMode(GL_PROJECTION) glLoadIdentity() a = np.array(m.copyDataTo()).reshape((4,4)) glMultMatrixf(a.transpose()) def projectionMatrix(self, region=None): # Xw = (Xnd + 1) * width/2 + X if region is None: region = (0, 0, self.width(), self.height()) x0, y0, w, h = self.getViewport() dist = self.opts['distance'] fov = self.opts['fov'] nearClip = dist * 0.001 farClip = dist * 1000. r = nearClip * np.tan(fov * 0.5 * np.pi / 180.) t = r * h / w # convert screen coordinates (region) to normalized device coordinates # Xnd = (Xw - X0) * 2/width - 1 ## Note that X0 and width in these equations must be the values used in viewport left = r * ((region[0]-x0) * (2.0/w) - 1) right = r * ((region[0]+region[2]-x0) * (2.0/w) - 1) bottom = t * ((region[1]-y0) * (2.0/h) - 1) top = t * ((region[1]+region[3]-y0) * (2.0/h) - 1) tr = QtGui.QMatrix4x4() tr.frustum(left, right, bottom, top, nearClip, farClip) return tr def setModelview(self): glMatrixMode(GL_MODELVIEW) glLoadIdentity() m = self.viewMatrix() a = np.array(m.copyDataTo()).reshape((4,4)) glMultMatrixf(a.transpose()) def viewMatrix(self): tr = QtGui.QMatrix4x4() tr.translate( 0.0, 0.0, -self.opts['distance']) tr.rotate(self.opts['elevation']-90, 1, 0, 0) tr.rotate(self.opts['azimuth']+90, 0, 0, -1) center = self.opts['center'] tr.translate(-center.x(), -center.y(), -center.z()) return tr
[docs] def itemsAt(self, region=None): """ Return a list of the items displayed in the region (x, y, w, h) relative to the widget. """ region = (region[0], self.height()-(region[1]+region[3]), region[2], region[3]) #buf = np.zeros(100000, dtype=np.uint) buf = glSelectBuffer(100000) try: glRenderMode(GL_SELECT) glInitNames() glPushName(0) self._itemNames = {} self.paintGL(region=region, useItemNames=True) finally: hits = glRenderMode(GL_RENDER) items = [(h.near, h.names[0]) for h in hits] items.sort(key=lambda i: i[0]) return [self._itemNames[i[1]] for i in items]
[docs] def paintGL(self, region=None, viewport=None, useItemNames=False): """ viewport specifies the arguments to glViewport. If None, then we use self.opts['viewport'] region specifies the sub-region of self.opts['viewport'] that should be rendered. Note that we may use viewport != self.opts['viewport'] when exporting. """ if viewport is None: glViewport(*self.getViewport()) else: glViewport(*viewport) self.setProjection(region=region) self.setModelview() bgcolor = self.opts['bgcolor'] glClearColor(*bgcolor) glClear( GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT ) self.drawItemTree(useItemNames=useItemNames)
def drawItemTree(self, item=None, useItemNames=False): if item is None: items = [x for x in self.items if x.parentItem() is None] else: items = item.childItems() items.append(item) items.sort(key=lambda a: a.depthValue()) for i in items: if not i.visible(): continue if i is item: try: glPushAttrib(GL_ALL_ATTRIB_BITS) if useItemNames: glLoadName(i._id) self._itemNames[i._id] = i i.paint() except: from .. import debug debug.printExc() msg = "Error while drawing item %s." % str(item) ver = glGetString(GL_VERSION) if ver is not None: ver = ver.split()[0] if int(ver.split(b'.')[0]) < 2: print(msg + " The original exception is printed above; however, pyqtgraph requires OpenGL version 2.0 or greater for many of its 3D features and your OpenGL version is %s. Installing updated display drivers may resolve this issue." % ver) else: print(msg) finally: glPopAttrib() else: glMatrixMode(GL_MODELVIEW) glPushMatrix() try: tr = i.transform() a = np.array(tr.copyDataTo()).reshape((4,4)) glMultMatrixf(a.transpose()) self.drawItemTree(i, useItemNames=useItemNames) finally: glMatrixMode(GL_MODELVIEW) glPopMatrix() def setCameraPosition(self, pos=None, distance=None, elevation=None, azimuth=None): if distance is not None: self.opts['distance'] = distance if elevation is not None: self.opts['elevation'] = elevation if azimuth is not None: self.opts['azimuth'] = azimuth self.update()
[docs] def cameraPosition(self): """Return current position of camera based on center, dist, elevation, and azimuth""" center = self.opts['center'] dist = self.opts['distance'] elev = self.opts['elevation'] * np.pi/180. azim = self.opts['azimuth'] * np.pi/180. pos = Vector( center.x() + dist * np.cos(elev) * np.cos(azim), center.y() + dist * np.cos(elev) * np.sin(azim), center.z() + dist * np.sin(elev) ) return pos
[docs] def orbit(self, azim, elev): """Orbits the camera around the center position. *azim* and *elev* are given in degrees.""" self.opts['azimuth'] += azim #self.opts['elevation'] += elev self.opts['elevation'] = np.clip(self.opts['elevation'] + elev, -90, 90) self.update()
[docs] def pan(self, dx, dy, dz, relative=False): """ Moves the center (look-at) position while holding the camera in place. If relative=True, then the coordinates are interpreted such that x if in the global xy plane and points to the right side of the view, y is in the global xy plane and orthogonal to x, and z points in the global z direction. Distances are scaled roughly such that a value of 1.0 moves by one pixel on screen. """ if not relative: self.opts['center'] += QtGui.QVector3D(dx, dy, dz) else: cPos = self.cameraPosition() cVec = self.opts['center'] - cPos dist = cVec.length() ## distance from camera to center xDist = dist * 2. * np.tan(0.5 * self.opts['fov'] * np.pi / 180.) ## approx. width of view at distance of center point xScale = xDist / self.width() zVec = QtGui.QVector3D(0,0,1) xVec = QtGui.QVector3D.crossProduct(zVec, cVec).normalized() yVec = QtGui.QVector3D.crossProduct(xVec, zVec).normalized() self.opts['center'] = self.opts['center'] + xVec * xScale * dx + yVec * xScale * dy + zVec * xScale * dz self.update()
[docs] def pixelSize(self, pos): """ Return the approximate size of a screen pixel at the location pos Pos may be a Vector or an (N,3) array of locations """ cam = self.cameraPosition() if isinstance(pos, np.ndarray): cam = np.array(cam).reshape((1,)*(pos.ndim-1)+(3,)) dist = ((pos-cam)**2).sum(axis=-1)**0.5 else: dist = (pos-cam).length() xDist = dist * 2. * np.tan(0.5 * self.opts['fov'] * np.pi / 180.) return xDist / self.width()
def mousePressEvent(self, ev): self.mousePos = ev.pos() def mouseMoveEvent(self, ev): diff = ev.pos() - self.mousePos self.mousePos = ev.pos() if ev.buttons() == QtCore.Qt.LeftButton: self.orbit(-diff.x(), diff.y()) #print self.opts['azimuth'], self.opts['elevation'] elif ev.buttons() == QtCore.Qt.MidButton: if (ev.modifiers() & QtCore.Qt.ControlModifier): self.pan(diff.x(), 0, diff.y(), relative=True) else: self.pan(diff.x(), diff.y(), 0, relative=True) def mouseReleaseEvent(self, ev): pass # Example item selection code: #region = (ev.pos().x()-5, ev.pos().y()-5, 10, 10) #print(self.itemsAt(region)) ## debugging code: draw the picking region #glViewport(*self.getViewport()) #glClear( GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT ) #region = (region[0], self.height()-(region[1]+region[3]), region[2], region[3]) #self.paintGL(region=region) #self.swapBuffers() def wheelEvent(self, ev): delta = 0 if not USE_PYQT5: delta = ev.delta() else: delta = ev.angleDelta().x() if delta == 0: delta = ev.angleDelta().y() if (ev.modifiers() & QtCore.Qt.ControlModifier): self.opts['fov'] *= 0.999**delta else: self.opts['distance'] *= 0.999**delta self.update() def keyPressEvent(self, ev): if ev.key() in self.noRepeatKeys: ev.accept() if ev.isAutoRepeat(): return self.keysPressed[ev.key()] = 1 self.evalKeyState() def keyReleaseEvent(self, ev): if ev.key() in self.noRepeatKeys: ev.accept() if ev.isAutoRepeat(): return try: del self.keysPressed[ev.key()] except: self.keysPressed = {} self.evalKeyState() def evalKeyState(self): speed = 2.0 if len(self.keysPressed) > 0: for key in self.keysPressed: if key == QtCore.Qt.Key_Right: self.orbit(azim=-speed, elev=0) elif key == QtCore.Qt.Key_Left: self.orbit(azim=speed, elev=0) elif key == QtCore.Qt.Key_Up: self.orbit(azim=0, elev=-speed) elif key == QtCore.Qt.Key_Down: self.orbit(azim=0, elev=speed) elif key == QtCore.Qt.Key_PageUp: pass elif key == QtCore.Qt.Key_PageDown: pass self.keyTimer.start(16) else: self.keyTimer.stop() def checkOpenGLVersion(self, msg): ## Only to be called from within exception handler. ver = glGetString(GL_VERSION).split()[0] if int(ver.split('.')[0]) < 2: from .. import debug pyqtgraph.debug.printExc() raise Exception(msg + " The original exception is printed above; however, pyqtgraph requires OpenGL version 2.0 or greater for many of its 3D features and your OpenGL version is %s. Installing updated display drivers may resolve this issue." % ver) else: raise
[docs] def readQImage(self): """ Read the current buffer pixels out as a QImage. """ w = self.width() h = self.height() self.repaint() pixels = np.empty((h, w, 4), dtype=np.ubyte) pixels[:] = 128 pixels[...,0] = 50 pixels[...,3] = 255 glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, pixels) # swap B,R channels for Qt tmp = pixels[...,0].copy() pixels[...,0] = pixels[...,2] pixels[...,2] = tmp pixels = pixels[::-1] # flip vertical img = fn.makeQImage(pixels, transpose=False) return img
def renderToArray(self, size, format=GL_BGRA, type=GL_UNSIGNED_BYTE, textureSize=1024, padding=256): w,h = map(int, size) self.makeCurrent() tex = None fb = None try: output = np.empty((w, h, 4), dtype=np.ubyte) fb = glfbo.glGenFramebuffers(1) glfbo.glBindFramebuffer(glfbo.GL_FRAMEBUFFER, fb ) glEnable(GL_TEXTURE_2D) tex = glGenTextures(1) glBindTexture(GL_TEXTURE_2D, tex) texwidth = textureSize data = np.zeros((texwidth,texwidth,4), dtype=np.ubyte) ## Test texture dimensions first glTexImage2D(GL_PROXY_TEXTURE_2D, 0, GL_RGBA, texwidth, texwidth, 0, GL_RGBA, GL_UNSIGNED_BYTE, None) if glGetTexLevelParameteriv(GL_PROXY_TEXTURE_2D, 0, GL_TEXTURE_WIDTH) == 0: raise Exception("OpenGL failed to create 2D texture (%dx%d); too large for this hardware." % shape[:2]) ## create teture glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texwidth, texwidth, 0, GL_RGBA, GL_UNSIGNED_BYTE, data.transpose((1,0,2))) self.opts['viewport'] = (0, 0, w, h) # viewport is the complete image; this ensures that paintGL(region=...) # is interpreted correctly. p2 = 2 * padding for x in range(-padding, w-padding, texwidth-p2): for y in range(-padding, h-padding, texwidth-p2): x2 = min(x+texwidth, w+padding) y2 = min(y+texwidth, h+padding) w2 = x2-x h2 = y2-y ## render to texture glfbo.glFramebufferTexture2D(glfbo.GL_FRAMEBUFFER, glfbo.GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex, 0) self.paintGL(region=(x, h-y-h2, w2, h2), viewport=(0, 0, w2, h2)) # only render sub-region ## read texture back to array data = glGetTexImage(GL_TEXTURE_2D, 0, format, type) data = np.fromstring(data, dtype=np.ubyte).reshape(texwidth,texwidth,4).transpose(1,0,2)[:, ::-1] output[x+padding:x2-padding, y+padding:y2-padding] = data[padding:w2-padding, -(h2-padding):-padding] finally: self.opts['viewport'] = None glfbo.glBindFramebuffer(glfbo.GL_FRAMEBUFFER, 0) glBindTexture(GL_TEXTURE_2D, 0) if tex is not None: glDeleteTextures([tex]) if fb is not None: glfbo.glDeleteFramebuffers([fb]) return output