Edge color in MeshVisual

[ManuGraiph]

Hi! I'm plotting a mesh using:

MeshV = scene.visuals.create_visual_node(visuals.MeshVisual)
m1 = MeshV(parent=view.scene)
m1.set_data(vertices=mesh.points(),faces=np.array(mesh.faces()),face_colors=color_array_here)

Now, is there any way to change the colors of the edges in the mesh (the lines connecting the triangle vertices)?

[djhoese]

There is a vertex_colors keyword argument.

vispy/vispy/visuals/mesh.py

Lines 166 to 167 in 16d8c5b

	vertex_colors : array-like | None
	Colors to use for each vertex.

Does that handle it? Otherwise I think you'd need to make a LineVisual that has the same vertex points and control those colors. I think that's how it is done in other compound visuals (visuals that use multiple other visuals).

There are only the concepts of faces and vertices in a MeshVisual it seems.

[ManuGraiph]

No, i'm asking for the edge colours, not the vertex colors.

I thought maybe there was some built-in arg for it.

[djhoese]

There is for other Visuals that uses Meshes like the BoxVisual where it uses a Mesh for the object then another Mesh for the edges apparently:

vispy/vispy/visuals/box.py

Lines 51 to 57 in 16d8c5b

	self._mesh = MeshVisual(vertices['position'], filled_indices,
	vertex_colors, face_colors, color)
	if edge_color:
	self._border = MeshVisual(vertices['position'], outline_indices,
	color=edge_color, mode='lines')
	else:
	self._border = MeshVisual()

But then you have Visuals like PolygonVisual that uses a Mesh and a Line:

vispy/vispy/visuals/polygon.py

Lines 54 to 66 in 16d8c5b

	self._mesh = MeshVisual()
	self._border = LineVisual(method=border_method)
	self._pos = pos
	self._color = Color(color)
	self._border_width = border_width
	self._border_color = Color(border_color)
	self._triangulate = triangulate
	self._update()
	CompoundVisual.__init__(self, [self._mesh, self._border], **kwargs)
	self._mesh.set_gl_state(polygon_offset_fill=True,
	polygon_offset=(1, 1), cull_face=False)
	self.freeze()

[ManuGraiph]

Ohh, interesting.. it seems that with the mode = 'lines' it only plots the wireframe if the mesh and then the color arg is the edge color. I'm gonna give it a try, thanks!!