gistfile1.txt

def do_magic(context):
    lights = []
    for o in context.scene.objects:
        if o.type == "LAMP":
            lights.append(o)
    print(lights)
    obj = context.active_object
    bm = bmesh.new() 
    mesh = obj.data
    bm.from_mesh(mesh)
    color = bm.loops.layers.color[0]
    for face in bm.faces:
        for loop in face.loops:
            vcol = loop[color]
            vquat = obj.matrix_world.decompose()[1]
            v = loop.vert 
            n = v.normal * obj.matrix_world.inverted()
            co = (vquat * v.co) + obj.location #* obj.matrix_world
            final = Vector((0,0,0)) 
            for lamp in lights:
                lv = lamp.location - co
                distance = lv.length / (lamp.data.distance)
                energy = lamp.data.energy*10
                lcolor = lamp.data.color

                intensity = (1/(distance*distance))*energy

                d = n.dot(lv)
                f = d*(intensity)
                if d > 0:
                    final = final + (Vector((lcolor.r,lcolor.g,lcolor.b))  * f)

            lc = Vector((vcol.r,vcol.b,vcol.g))  
            fc = final * lc
            # print("-------")
            # print(final)
            # print( lc )
            #print((final*lc)[0]+":"+(final*lc)[1]+":"+(final*lc)[2])
            loop[color] = (final[0], final[1], final[2])
    bm.to_mesh(mesh)