pygel3d.gl_display

 1""" This modules provides an OpenGL based viewer for graphs and meshes """
 2from pygel3d import hmesh, graph, lib_py_gel
 3import ctypes as ct
 4import numpy as np
 5from os import getcwd, chdir
 6
 7try:
 8    lib_py_gel.GLManifoldViewer_new.restype = ct.c_void_p
 9    lib_py_gel.GLManifoldViewer_delete.argtypes = (ct.c_void_p,)
10    lib_py_gel.GLManifoldViewer_display.argtypes = (ct.c_void_p,ct.c_void_p,ct.c_void_p,ct.c_char,ct.c_bool, ct.POINTER(ct.c_float*3), ct.POINTER(ct.c_double),ct.c_bool,ct.c_bool)
11    lib_py_gel.GLManifoldViewer_get_annotation_points.restype = ct.c_size_t
12    lib_py_gel.GLManifoldViewer_get_annotation_points.argtypes = (ct.c_void_p, ct.POINTER(ct.POINTER(ct.c_double)))
13    lib_py_gel.GLManifoldViewer_set_annotation_points.argtypes = (ct.c_void_p, ct.c_int, ct.POINTER(ct.c_double))
14    lib_py_gel.GLManifoldViewer_event_loop.argtypes = (ct.c_bool,)
15    class Viewer:
16        """ An OpenGL Viewer for Manifolds and Graphs. Having created an instance of this
17        class, call display to show a mesh or a graph. The display function is flexible,
18        allowing several types of interactive visualization. Each instance of this
19        class corresponds to a single window, but you can have several
20        GLManifoldViewer and hence also several windows showing different
21        visualizations. """
22        def __init__(self):
23            current_directory = getcwd()
24            self.obj = lib_py_gel.GLManifoldViewer_new()
25            chdir(current_directory) # Necessary because init_glfw changes cwd
26        def __del__(self):
27            lib_py_gel.GLManifoldViewer_delete(self.obj)
28        def display(self, m, g=None, mode='w', smooth=True, bg_col=[0.3,0.3,0.3], data=None, reset_view=False, once=False):
29            """ Display a mesh
30
31            Args:
32            ---
33            - m : the Manifold mesh or Graph we want to show.
34            - g : the Graph we want to show. If you only want to show a graph, you
35                can simply pass the graph as m, so the g argument is relevant only if
36                you need to show both a Manifold _and_ a Graph.
37            - mode : a single character that determines how the mesh is visualized:
38                'w' - wireframe,
39                'i' - isophote,
40                'g' - glazed (try it and see),
41                's' - scalar field,
42                'l' - line field,
43                'n' - normal.
44                'x' - xray or ghost rendering. Useful to show Manifold on top of Graph
45            - smooth : if True we use vertex normals. Otherwise, face normals.
46            - bg_col : background color.
47            - data : per vertex data for visualization. scalar or vector field.
48            - reset_view : if False view is as left in the previous display call. If
49                True, the view is reset to the default.
50            - once : if True we immediately exit the event loop and return. However,
51                the window stays and if the event loop is called from this or any
52                other viewer, the window will still be responsive.
53
54            Interactive controls:
55            ---
56            When a viewer window is displayed on the screen, you can naviagate with
57            the mouse: Left mouse button rotates, right mouse button is used for
58            zooming and (if shift is pressed) for panning. If you hold control, any
59            mouse button will pick a point on the 3D model. Up to 19 of these points
60            have unique colors.  If you pick an already placed annotation point it
61            will be removed and can now be placed elsewhere. Hit space bar to clear
62            the annotation points. Hitting ESC exits the event loop causing control
63            to return to the script.
64            """
65            data_ct = np.array(data,dtype=ct.c_double).ctypes
66            data_a = data_ct.data_as(ct.POINTER(ct.c_double))
67            bg_col_ct = np.array(bg_col,dtype=ct.c_float).ctypes
68            bg_col_a = bg_col_ct.data_as(ct.POINTER(ct.c_float*3))
69            if isinstance(m,graph.Graph):
70                g = m
71                m = None
72            if isinstance(m,hmesh.Manifold) and isinstance(g,graph.Graph):
73                lib_py_gel.GLManifoldViewer_display(self.obj, m.obj, g.obj, ct.c_char(mode.encode('ascii')),smooth,bg_col_a,data_a,reset_view,once)
74            elif isinstance(m,hmesh.Manifold):
75                lib_py_gel.GLManifoldViewer_display(self.obj, m.obj, 0, ct.c_char(mode.encode('ascii')),smooth,bg_col_a,data_a,reset_view,once)
76            elif isinstance(g,graph.Graph):
77                lib_py_gel.GLManifoldViewer_display(self.obj, 0, g.obj, ct.c_char(mode.encode('ascii')),smooth,bg_col_a,data_a,reset_view,once)
78                
79        def annotation_points(self):
80            """ Retrieve a vector of annotation points. This vector is not a copy,
81            so any changes made to the points will be reflected in the viewer. """
82            pos = ct.POINTER(ct.c_double)()
83            n = lib_py_gel.GLManifoldViewer_get_annotation_points(self.obj, ct.byref(pos))
84            if n == 0:
85                return None
86            return np.ctypeslib.as_array(pos,(n,3))
87        def set_annotation_points(self, pts):
88            n = int(np.size(pts)/3)
89            pts_ct = np.array(pts,dtype=ct.c_double).ctypes
90            pts_a = pts_ct.data_as(ct.POINTER(ct.c_double))
91            lib_py_gel.GLManifoldViewer_set_annotation_points(self.obj, n, pts_a)
92        @staticmethod
93        def event_loop():
94            """ Explicit call to the event loop. This function enters the event loop.
95            Call it if you want to turn on interactivity in the currently displayed
96            window."""
97            lib_py_gel.GLManifoldViewer_event_loop(False)
98except AttributeError:
99    pass