Ports scanline HUDs from nebula. (#8675)

code/_onclick/hud/hud.dm

@@ -21,7 +21,7 @@ var/list/global_huds
 	var/obj/screen/science
 	var/obj/screen/holomap
 
-/datum/global_hud/proc/setup_overlay(var/icon_state)
+/datum/global_hud/proc/setup_overlay(var/icon_state, var/color)
 	var/obj/screen/screen = new /obj/screen()
 	screen.alpha = 25 // Adjust this if you want goggle overlays to be thinner or thicker.
 	screen.screen_loc = "SOUTHWEST to NORTHEAST" // Will tile up to the whole screen, scaling beyond 15x15 if needed.
@@ -29,6 +29,7 @@ var/list/global_huds
 	screen.icon_state = icon_state
 	screen.layer = SCREEN_LAYER
 	screen.mouse_opacity = 0
+	screen.color = color
 
 	return screen
 
@@ -47,10 +48,10 @@ var/list/global_huds
 	blurry.layer = 17
 	blurry.mouse_opacity = 0
 
-	nvg = setup_overlay("nvg_hud")
-	thermal = setup_overlay("thermal_hud")
-	meson = setup_overlay("meson_hud")
-	science = setup_overlay("science_hud")
+	nvg = setup_overlay("scanline", "#06ff00")
+	thermal = setup_overlay("scanline", "#ff0000")
+	meson = setup_overlay("scanline", "#9fd800")
+	science = setup_overlay("scanline", "#d600d6")
 
 	// The holomap screen object is actually totally invisible.
 	// Station maps work by setting it as an images location before sending to client, not

html/changelogs/mattatlas-scanline.yml

@@ -0,0 +1,41 @@
+################################
+# Example Changelog File
+#
+# Note: This file, and files beginning with ".", and files that don't end in ".yml" will not be read. If you change this file, you will look really dumb.
+#
+# Your changelog will be merged with a master changelog. (New stuff added only, and only on the date entry for the day it was merged.)
+# When it is, any changes listed below will disappear.
+#
+# Valid Prefixes: 
+#   bugfix
+#   wip (For works in progress)
+#   tweak
+#   soundadd
+#   sounddel
+#   rscadd (general adding of nice things)
+#   rscdel (general deleting of nice things)
+#   imageadd
+#   imagedel
+#   maptweak
+#   spellcheck (typo fixes)
+#   experiment
+#   balance
+#   admin
+#   backend
+#   security
+#   refactor
+#################################
+
+# Your name.  
+author: MattAtlas
+
+# Optional: Remove this file after generating master changelog.  Useful for PR changelogs that won't get used again.
+delete-after: True
+
+# Any changes you've made.  See valid prefix list above.
+# INDENT WITH TWO SPACES.  NOT TABS.  SPACES.
+# SCREW THIS UP AND IT WON'T WORK.
+# Also, all entries are changed into a single [] after a master changelog generation. Just remove the brackets when you add new entries.
+# Please surround your changes in  double quotes ("), as certain characters otherwise screws up compiling. The quotes will not show up in the changelog.
+changes: 
+  - rscadd: "Mesons, NVGs, science goggles and such all have scanline effects now."