Allow display dimming/vignette

Deeper dimming/vignette when server is empty
to make it a little more visually interesting, plus
add a clearer indication that the server is in
a different state than normal play.

szutil_cinecam/init.lua

@@ -1,8 +1,10 @@
 -- LUALOCALS < ---------------------------------------------------------
 local ipairs, math, minetest, pairs, type
     = ipairs, math, minetest, pairs, type
-local math_atan2, math_cos, math_pi, math_random, math_sin, math_sqrt
-    = math.atan2, math.cos, math.pi, math.random, math.sin, math.sqrt
+local math_atan2, math_ceil, math_cos, math_pi, math_random, math_sin,
+      math_sqrt
+    = math.atan2, math.ceil, math.cos, math.pi, math.random, math.sin,
+      math.sqrt
 -- LUALOCALS > ---------------------------------------------------------
 
 local cycletime = 20 -- time between cycles
@@ -23,6 +25,11 @@ local minlight = 4 -- min light level to not affect cam time
 local maxidle = 10 -- max idle time before penalty
 local idlepenalty = 4 -- extra countdown speed for being idle
 
+local actvig = 0.25 -- vignette when active
+local actdark = 0 -- darken when active
+local dummyvig = 0.75 -- vignette when dummycam
+local dummydark = 0.3 -- darken when dummycam
+
 local modname = minetest.get_current_modname()
 
 minetest.register_privilege(modname, {
@@ -108,6 +115,45 @@ do
 	end
 end
 
+local function hudset(player, data, key, def)
+	local hud = data[key]
+	if hud then
+		if hud.text == def.text then return end
+		player:hud_change(hud.id, "text", def.text)
+		hud.text = def.text
+	else
+		data[key] = {
+			id = player:hud_add(def),
+			text = def.text
+		}
+	end
+end
+
+local function dimhuds(player, data, darken, vignette)
+	hudset(player, data, "darken", {
+			hud_elem_type = "image",
+			position = {x = 0.5, y = 0.5},
+			text = darken == 0 and "" or (
+				"[combine:1x1^[noalpha^[opacity:"
+				.. math_ceil(255 * darken)),
+			direction = 0,
+			scale = {x = -100, y = -100},
+			offset = {x = 0, y = 0},
+			quick = true
+		})
+	hudset(player, data, "vignette", {
+			hud_elem_type = "image",
+			position = {x = 0.5, y = 0.5},
+			text = vignette == 0 and "" or (
+				"szutil_cinecam_vignette.png^[opacity:"
+				.. math_ceil(255 * vignette)),
+			direction = 0,
+			scale = {x = -100, y = -100},
+			offset = {x = 0, y = 0},
+			quick = true
+		})
+end
+
 local function camdummy(player, data, dtime)
 	data.dummycam = (data.dummycam or 0) - dtime
 	if data.dummycam > 0 then
@@ -130,6 +176,8 @@ local function camdummy(player, data, dtime)
 	local tpos = vector.multiply(dpos, (len - dummyclear) / len)
 
 	if sightblocked(dpos, tpos) then return end
+
+	dimhuds(player, data, dummydark, dummyvig)
 	setcamera(player, dpos, tpos)
 	data.dummycam = cycletime
 end
@@ -141,31 +189,17 @@ local function camcheck(player, dtime)
 	if data.target then
 		text = "Watching: " .. data.target
 	end
-	if data.tip then
-		if text ~= data.tip.text then data.tip.time = 0 end
-		data.tip.text = text
-		local show = text
-		if data.tip.time >= hudtime then show = "" end
-		if data.tip.show ~= show then
-			player:hud_change(data.tip.id, "text", show)
-			data.tip.show = text
-		end
-		data.tip.time = data.tip.time + dtime
-	elseif text ~= "" then
-		data.tip = {
-			id = player:hud_add({
+	if data.tiptext ~= text then data.tiptime = 0 end
+	data.tiptext = text
+	if data.tiptime > hudtime then text = "" end
+	hudset(player, data, "tip", {
 			hud_elem_type = "text",
 			position = {x = 0.5, y = 1},
 			text = text,
 			number = 0xFFFFFF,
 			alignment = {x = 0, y = -1},
 			offset = {x = 0, y = -8},
-				}),
-			text = text,
-			show = text,
-			time = 0
-		}
-	end
+		})
 
 	if data.locked then
 		data.locked = data.locked - dtime
@@ -243,6 +277,7 @@ local function camcheck(player, dtime)
 
 		if not allow(trypos) then return end
 
+		dimhuds(player, data, actdark, actvig)
 		setcamera(player, trypos, tpos)
 
 		data.moved = 0