[FIXED] Make transparent items when drawing using GLMeshItem pyqtgraph

Issue

I am trying to use

gl.GLMeshItem(vertexes=sel_vertices, faces=sel_face_idx, faceColors=colors,
                             drawEdges=True, edgeColor=colors)

to plot faces of selected vertices of triangles. The color includes four elements for RGBA, I tried to change the fourth element to change the transparent but there is no effect.

I also read several threads. Someone suggested:

from OpenGL.GL import *
glBlendFunc  (GL_ONE_MINUS_SRC_ALPHA, GL_SRC_ALPHA)
glEnable     (GL_BLEND)
glEnable     (GL_COLOR_MATERIAL)

However, the problem still cannot be solved. How could I do that?

Solution

the following lines should be added after initializing the widget view, i.e.:

gl.GLViewWidget()
glBlendFunc(GL_ONE_MINUS_SRC_ALPHA, GL_SRC_ALPHA)
glEnable(GL_BLEND)
glEnable(GL_COLOR_MATERIAL)

Answered By - Karim