from OpenGL.GL import * # noqa
import numpy as np
from ..MeshData import MeshData
from .GLMeshItem import GLMeshItem
__all__ = ['GLSurfacePlotItem']
[docs]
class GLSurfacePlotItem(GLMeshItem):
"""
**Bases:** :class:`GLMeshItem <pyqtgraph.opengl.GLMeshItem>`
Displays a surface plot on a regular x,y grid
"""
[docs]
def __init__(self, x=None, y=None, z=None, colors=None, parentItem=None, **kwds):
"""
The x, y, z, and colors arguments are passed to setData().
All other keyword arguments are passed to GLMeshItem.__init__().
"""
self._x = None
self._y = None
self._z = None
self._color = None
self._vertexes = None
self._meshdata = MeshData()
super().__init__(parentItem=parentItem, meshdata=self._meshdata, **kwds)
self.setData(x, y, z, colors)
[docs]
def setData(self, x=None, y=None, z=None, colors=None):
"""
Update the data in this surface plot.
============== =====================================================================
**Arguments:**
x,y 1D arrays of values specifying the x,y positions of vertexes in the
grid. If these are omitted, then the values will be assumed to be
integers.
z 2D array of height values for each grid vertex.
colors (width, height, 4) array of vertex colors.
============== =====================================================================
All arguments are optional.
Note that if vertex positions are updated, the normal vectors for each triangle must
be recomputed. This is somewhat expensive if the surface was initialized with smooth=False
and very expensive if smooth=True. For faster performance, initialize with
computeNormals=False and use per-vertex colors or a normal-independent shader program.
"""
if x is not None:
if self._x is None or len(x) != len(self._x):
self._vertexes = None
self._x = x
if y is not None:
if self._y is None or len(y) != len(self._y):
self._vertexes = None
self._y = y
if z is not None:
#if self._x is None:
#self._x = np.arange(z.shape[0])
#self._vertexes = None
#if self._y is None:
#self._y = np.arange(z.shape[1])
#self._vertexes = None
if self._x is not None and z.shape[0] != len(self._x):
raise Exception('Z values must have shape (len(x), len(y))')
if self._y is not None and z.shape[1] != len(self._y):
raise Exception('Z values must have shape (len(x), len(y))')
self._z = z
if self._vertexes is not None and self._z.shape != self._vertexes.shape[:2]:
self._vertexes = None
if colors is not None:
self._colors = colors
self._meshdata.setVertexColors(colors)
if self._z is None:
return
updateMesh = False
newVertexes = False
## Generate vertex and face array
if self._vertexes is None:
newVertexes = True
self._vertexes = np.empty((self._z.shape[0], self._z.shape[1], 3), dtype=float)
self.generateFaces()
self._meshdata.setFaces(self._faces)
updateMesh = True
## Copy x, y, z data into vertex array
if newVertexes or x is not None:
if x is None:
if self._x is None:
x = np.arange(self._z.shape[0])
else:
x = self._x
self._vertexes[:, :, 0] = x.reshape(len(x), 1)
updateMesh = True
if newVertexes or y is not None:
if y is None:
if self._y is None:
y = np.arange(self._z.shape[1])
else:
y = self._y
self._vertexes[:, :, 1] = y.reshape(1, len(y))
updateMesh = True
if newVertexes or z is not None:
self._vertexes[...,2] = self._z
updateMesh = True
## Update MeshData
if updateMesh:
self._meshdata.setVertexes(self._vertexes.reshape(self._vertexes.shape[0]*self._vertexes.shape[1], 3))
self.meshDataChanged()
def generateFaces(self):
cols = self._z.shape[1]-1
rows = self._z.shape[0]-1
faces = np.empty((cols*rows*2, 3), dtype=np.uint)
rowtemplate1 = np.arange(cols).reshape(cols, 1) + np.array([[0, 1, cols+1]])
rowtemplate2 = np.arange(cols).reshape(cols, 1) + np.array([[cols+1, 1, cols+2]])
for row in range(rows):
start = row * cols * 2
faces[start:start+cols] = rowtemplate1 + row * (cols+1)
faces[start+cols:start+(cols*2)] = rowtemplate2 + row * (cols+1)
self._faces = faces
