test

donkle.py

import bpy
import bgl
from bpy_extras.view3d_utils import location_3d_to_region_2d as loc3d2d

# (...)

def draw_points(context, points, size, gl_col):
    """
    input 
    - context:  bpy.context ( a 3d view )
    - points:   a list/iterable of proper vectors
    - size:     dot/vertex size, pixels
    - gl_col:   rgba as tuple (0.2, 0.9, 0.2, .2)

    outpt
    - draws points to screen.

    loc3d2d is renamed during import purely 
    because it's a big whopping function name

    """
    region = context.region
    rv3d = context.space_data.region_3d
    
    this_object = context.active_object
    matrix_world = this_object.matrix_world  
    
    # needed for adjusting the size of gl_points    
    bgl.glEnable(bgl.GL_POINT_SMOOTH)
    bgl.glPointSize(size)
    bgl.glBlendFunc(bgl.GL_SRC_ALPHA, bgl.GL_ONE_MINUS_SRC_ALPHA)
    
    bgl.glBegin(bgl.GL_POINTS)
    bgl.glColor4f(*gl_col)    

    # for each vector in points, call bgl.glVertex2f
    for coord in points:
        vector3d = matrix_world * coord
        vector2d = loc3d2d(region, rv3d, vector3d) # returns a 2-tuple
        bgl.glVertex2f(*vector2d) # needs a 2d vector to draw to 2d screen
    bgl.glEnd()
    
    bgl.glDisable(bgl.GL_POINT_SMOOTH)
    bgl.glDisable(bgl.GL_POINTS)
    return