add showtime dynamics to sunbeams

sunbeam multiplier: fade factor is multiplicative, with an additional initial "attack" factor (simple linear fade-in to avoid instant flashes while also allowing the fadeout)

darken: fade factor is additive

Author: pingu7867

lua/pac3/core/client/parts/sunbeams.lua

@@ -11,18 +11,36 @@ local draw_distance = CreateClientConVar("pac_limit_sunbeams_draw_distance", "10
 
 
 BUILDER:StartStorableVars()
-	BUILDER:GetSet("Darken", 0)
-	BUILDER:GetSet("Multiplier", 0.25, {editor_sensitivity = 0.25})
-	BUILDER:GetSet("Size", 0.1, {editor_sensitivity = 0.25})
-	BUILDER:GetSet("DrawDistance", 1000, {editor_onchange = function(self, val) return math.max(val,0) end})
-	BUILDER:GetSet("Translucent", true)
+		BUILDER:GetSet("Darken", 0)
+		BUILDER:GetSet("Multiplier", 0.25, {editor_sensitivity = 0.25})
+		BUILDER:GetSet("Size", 0.1, {editor_sensitivity = 0.25})
+		BUILDER:GetSet("DrawDistance", 1000, {editor_onchange = function(self, val) return math.max(val,0) end})
+		BUILDER:GetSet("Translucent", true)
+
+	BUILDER:SetPropertyGroup("Showtime dynamics")
+		BUILDER:GetSet("EnableDynamics", false, {description = "If you want to make a fading effect, you can do it here instead of adding proxies.\nThe multiplier parts work multiplicatively, involving 3 terms: attack * multiplier * fade\nThe darken part works additively. It can add more darken on top of the existing darken value"})
+		BUILDER:GetSet("EndMultiplier", 1)
+		BUILDER:GetSet("StartMultiplier", 1)
+		BUILDER:GetSet("MultiplierFadePower", 1)
+		BUILDER:GetSet("MultiplierFadeSpeed", 1)
+		BUILDER:GetSet("MultiplierAttack", 0, {description = "Additional fade-in time to optionally soften the flash. This is in terms of normalized speed"})
+
+		BUILDER:GetSet("EndDarken", 0)
+		BUILDER:GetSet("StartDarken", 0)
+		BUILDER:GetSet("DarkenFadeSpeed", 1)
+		BUILDER:GetSet("DarkenFadePower", 1)
+
 BUILDER:EndStorableVars()
 
 function PART:GetNiceName()
 	local mult = self:GetMultiplier()
 	return mult > 0 and "bright sunbeams" or mult < 0 and "dark sunbeams" or self.ClassName
 end
 
+function PART:OnShow()
+	self.starttime = CurTime()
+end
+
 function PART:OnDraw()
 	if not DrawSunbeams then DrawSunbeams = _G.DrawSunbeams end
 
@@ -35,13 +53,38 @@ function PART:OnDraw()
 
 	local dist_mult = - math.Clamp(pac.EyePos:Distance(pos) / distance, 0, 1) + 1
 
-	DrawSunbeams(
-		self.Darken,
-		dist_mult * self.Multiplier * (math.Clamp(pac.EyeAng:Forward():Dot((pos - pac.EyePos):GetNormalized()) - 0.5, 0, 1) * 2) ^ 5,
-		self.Size,
-		spos.x / ScrW(),
-		spos.y / ScrH()
-	)
+	if self.EnableDynamics then
+		local lifetime = (CurTime() - self.starttime)
+
+		local init_mult = 1
+		if self.MultiplierAttack > 0 then init_mult = math.Clamp(lifetime*self.MultiplierAttack,0,1) end
+
+		local fade_factor_m = math.Clamp(lifetime*self.MultiplierFadeSpeed,0,1)
+		local fade_factor_d = math.Clamp(lifetime*self.DarkenFadeSpeed,0,1)
+		local final_mult_mult = self.EnableDynamics and
+			self.StartMultiplier + (self.EndMultiplier - self.StartMultiplier) * math.pow(fade_factor_m,self.MultiplierFadePower)
+			or self.Multiplier
+
+		local final_darken_add = self.EnableDynamics and
+			self.StartDarken + (self.EndDarken - self.StartDarken) * math.pow(fade_factor_d,self.DarkenFadePower)
+			or 0
+
+		DrawSunbeams(
+			self.Darken + final_darken_add,
+			dist_mult * init_mult * self.Multiplier * final_mult_mult * (math.Clamp(pac.EyeAng:Forward():Dot((pos - pac.EyePos):GetNormalized()) - 0.5, 0, 1) * 2) ^ 5,
+			self.Size,
+			spos.x / ScrW(),
+			spos.y / ScrH()
+		)
+	else
+		DrawSunbeams(
+			self.Darken,
+			dist_mult * self.Multiplier * (math.Clamp(pac.EyeAng:Forward():Dot((pos - pac.EyePos):GetNormalized()) - 0.5, 0, 1) * 2) ^ 5,
+			self.Size,
+			spos.x / ScrW(),
+			spos.y / ScrH()
+		)
+	end
 	cam.End2D()
 end