ID:2032640
 
Not a bug
BYOND Version:510.1322
Operating System:Windows 10 Home
Web Browser:Chrome 48.0.2564.103
Applies to:Dream Seeker
Status: Not a bug

This is not a bug. It may be an incorrect use of syntax or a limitation in the software. For further discussion on the matter, please consult the BYOND forums.
Descriptive Problem Summary:

Numbered Steps to Reproduce Problem:

Expected Results:
The void to remain black.


Actual Results:
The void becomes white.

image
masterplane
plane = 0
blend_mode = BLEND_MULTIPLY
appearance_flags = PLANE_MASTER | NO_CLIENT_COLOR
color = list(null,null,null,null,"#0000")
mouse_opacity = 0
dark
plane = -2
blend_mode = BLEND_ADD
mouse_opacity = 0
icon = 'darkness.dmi'

atom/movable/var/tmp/obj/light/light

obj/light_source
plane = -2
blend_mode = BLEND_ADD
icon = 'light.dmi'
mouse_opacity = 0
alpha = 255
pixel_x = -16
pixel_y = -16
I have the map's background set to black.
I'll need a demo project for this. The code alone won't be sufficient to test.

However, your masterplane has the wrong color set; that should be #000f, not #0000, since you'll want full alpha.

I'm also not sure if your darkness plane is setup correctly; since it's not a PLANE_MASTER, you'll need to make sure its positioning is correct.
Actually a typo in the code I uploaded for my lighting demo that I corrected and never uploaded since I was adding more stuff before the update, whoops :)
The darkness plane is actually to give finer control over the alpha and color values of the "black" you see, without it the master plane ends up pure black with no control over the alpha.

The darkness is just a pure white block scaled up to fill the screen, then given a lower alpha than the light sources.
After looking at your code, I found out this is not a bug.

The matrix you actually want for the regular-map plane (called lighting_plane in the code, a misnomer) is list(null,null,null,"#0000","#000f"), because you need everything to be forced to alpha=1 exactly. The reason you're seeing white voids is that those are places where no tiles are being drawn onto that plane, and they're ending up with alpha=0. Therefore those pixels don't have any impact when they're multiplied over your actual lighting plane.
Lummox JR resolved issue (Not a bug)
May God bless you q.q
Quick question, it LOOKS as if what you're seeing is the built in opacity=1 lighting turning white, I read through the comments and there's nothing talking about that, so I might just be entirely wrong but if I'm not.

How2change default opacity lighting colour?
By changing the color of a master plane on plane 0 you'll effectively alter the color of opacity.
In response to Nadrew
Nadrew wrote:
By changing the color of a master plane on plane 0 you'll effectively alter the color of opacity.

The color of opacity was already changable before 510. It's based on the background color of the map element in the interface.