Add core_mesh_data_source_color_map

Author: tpaviot

examples/core_mesh_data_source_color_map.py

@@ -0,0 +1,71 @@
+##Copyright 2021 Thomas Paviot ([email protected])
+##
+##This file is part of pythonOCC.
+##
+##pythonOCC is free software: you can redistribute it and/or modify
+##it under the terms of the GNU Lesser General Public License as published by
+##the Free Software Foundation, either version 3 of the License, or
+##(at your option) any later version.
+##
+##pythonOCC is distributed in the hope that it will be useful,
+##but WITHOUT ANY WARRANTY; without even the implied warranty of
+##MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+##GNU Lesser General Public License for more details.
+##
+##You should have received a copy of the GNU Lesser General Public License
+##along with pythonOCC.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+import random
+
+from OCC.Core.MeshDataSource import Mesh_DataSource
+from OCC.Core.RWStl import rwstl_ReadFile
+from OCC.Core.MeshVS import *
+from OCC.Core.Aspect import Aspect_SequenceOfColor
+from OCC.Core.Quantity import Quantity_Color, Quantity_NOC_RED, Quantity_NOC_BLUE1, Quantity_NOC_BLACK
+from OCC.Core.TColStd import TColStd_DataMapOfIntegerReal
+
+from OCC.Display.SimpleGui import init_display
+
+stl_filename = os.path.join('..', 'assets', 'models', 'fan.stl')
+
+# read the stl file
+a_stl_mesh = rwstl_ReadFile(stl_filename)
+
+# create the data source
+a_data_source = Mesh_DataSource(a_stl_mesh)
+
+# create a mesh from the data source
+a_mesh = MeshVS_Mesh()
+a_mesh.SetDataSource(a_data_source)
+
+# assign nodal builder to the mesh
+a_builder = MeshVS_NodalColorPrsBuilder(a_mesh, MeshVS_DMF_NodalColorDataPrs | MeshVS_DMF_OCCMask)
+a_builder.UseTexture(True)
+
+# prepare color map
+aColorMap = Aspect_SequenceOfColor()
+aColorMap.Append(Quantity_Color(Quantity_NOC_RED))
+aColorMap.Append(Quantity_Color(Quantity_NOC_BLUE1))
+
+# assign color scale map values (0..1) to nodes
+aScaleMap = TColStd_DataMapOfIntegerReal()
+
+# iterate through the nodes and add an node id and
+# an appropriate value to the map
+# color should be from 0. to 1.
+for anId in range(1000):  # TODO use the mesh number of nodes
+	aValue = random.uniform(0, 1)
+	aScaleMap.Bind(anId, aValue)
+
+# pass color map and color scale values to the builder
+a_builder.SetColorMap(aColorMap)
+a_builder.SetInvalidColor(Quantity_Color(Quantity_NOC_BLACK))
+a_builder.SetTextureCoords(aScaleMap)
+a_mesh.AddBuilder(a_builder, True)
+
+# display
+display, start_display, add_menu, add_function_to_menu = init_display()
+display.Context.Display(a_mesh, True)
+display.FitAll()
+start_display()