Added basic 3D line plot class

opengl/items/GLLinePlotItem.py

+from OpenGL.GL import *
+from OpenGL.arrays import vbo
+from .. GLGraphicsItem import GLGraphicsItem
+from .. import shaders
+from pyqtgraph import QtGui
+import numpy as np
+
+__all__ = ['GLLinePlotItem']
+
+class GLLinePlotItem(GLGraphicsItem):
+    """Draws line plots in 3D."""
+    
+    def __init__(self, **kwds):
+        GLGraphicsItem.__init__(self)
+        glopts = kwds.pop('glOptions', 'additive')
+        self.setGLOptions(glopts)
+        self.pos = None
+        self.width = 1.
+        self.color = (1.0,1.0,1.0,1.0)
+        self.setData(**kwds)
+    
+    def setData(self, **kwds):
+        """
+        Update the data displayed by this item. All arguments are optional; 
+        for example it is allowed to update spot positions while leaving 
+        colors unchanged, etc.
+        
+        ====================  ==================================================
+        Arguments:
+        ------------------------------------------------------------------------
+        pos                   (N,3) array of floats specifying point locations.
+        color                 tuple of floats (0.0-1.0) specifying
+                              a color for the entire item.
+        width                 float specifying line width
+        ====================  ==================================================
+        """
+        args = ['pos', 'color', 'width', 'connected']
+        for k in kwds.keys():
+            if k not in args:
+                raise Exception('Invalid keyword argument: %s (allowed arguments are %s)' % (k, str(args)))
+            
+        for arg in args:
+            if arg in kwds:
+                setattr(self, arg, kwds[arg])
+                #self.vbo.pop(arg, None)
+        self.update()
+
+    def initializeGL(self):
+        pass
+        
+    #def setupGLState(self):
+        #"""Prepare OpenGL state for drawing. This function is called immediately before painting."""
+        ##glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)  ## requires z-sorting to render properly.
+        #glBlendFunc(GL_SRC_ALPHA, GL_ONE)
+        #glEnable( GL_BLEND )
+        #glEnable( GL_ALPHA_TEST )
+        #glDisable( GL_DEPTH_TEST )
+        
+        ##glEnable( GL_POINT_SMOOTH )
+
+        ##glHint(GL_POINT_SMOOTH_HINT, GL_NICEST)
+        ##glPointParameterfv(GL_POINT_DISTANCE_ATTENUATION, (0, 0, -1e-3))
+        ##glPointParameterfv(GL_POINT_SIZE_MAX, (65500,))
+        ##glPointParameterfv(GL_POINT_SIZE_MIN, (0,))
+        
+    def paint(self):
+        if self.pos is None:
+            return
+        self.setupGLState()
+        
+        glEnableClientState(GL_VERTEX_ARRAY)
+        try:
+            glVertexPointerf(self.pos)
+            glColor4f(*self.color)
+            
+            glPointSize(self.width)
+            glDrawArrays(GL_LINE_STRIP, 0, self.pos.size / self.pos.shape[-1])
+        finally:
+            glDisableClientState(GL_VERTEX_ARRAY)
+    
+