[pob2-port] Fix calculation of inverted Resistances when having a source of Penetration

spec/System/TestSkills_spec.lua.rej

@@ -0,0 +1,22 @@
+diff a/spec/System/TestSkills_spec.lua b/spec/System/TestSkills_spec.lua	(rejected hunks)
+@@ -798,6 +798,20 @@ describe("TestSkills", function()
+ 		assert.True(build.calcsTab.mainEnv.enemyDB:Sum("BASE", nil, "FireResist") < fireResistWithoutPotentExposure)
+ 	end)
+
++	it("averages inverted elemental resistance after penetration", function()
++		build.skillsTab:PasteSocketGroup("Fireball 20/0  1")
++		build.configTab.input.enemyIsBoss = "None"
++		build.configTab.input.enemyFireResist = 50
++		build.configTab.input.customMods = "Hits have 50% chance to treat Enemy Monster Elemental Resistance values as inverted\nDamage Penetrates 50% of Enemy Fire Resistance"
++		build.configTab:BuildModList()
++		runCallback("OnFrame")
++
++		assert.are.equals(1.25, build.calcsTab.calcsOutput.FireEffMult)
++		local breakdownText = table.concat(build.calcsTab.calcsEnv.player.breakdown.FireEffMult, "\n")
++		assert.truthy(breakdownText:match("inverted hit"))
++		assert.truthy(breakdownText:match("weighted average"))
++	end)
++
+ 	it("Test granted skills with exposure stats make exposure configurable", function()
+ 		build.skillsTab:PasteSocketGroup("Fireball 20/0  1")
+ 		local spec = build.spec

src/Modules/CalcBreakdown.lua.rej

@@ -0,0 +1,45 @@
+diff a/src/Modules/CalcBreakdown.lua b/src/Modules/CalcBreakdown.lua	(rejected hunks)
+@@ -110,20 +110,29 @@ function breakdown.area(base, areaMod, total, incBreakpoint, moreBreakpoint, red
+ 	return out
+ end
+
+-function breakdown.effMult(damageType, resist, pen, taken, mult, takenMore, sourceRes, useRes, invertChance, minPen)
++function breakdown.effMult(damageType, resist, pen, taken, mult, takenMore, sourceRes, useRes, invertChance, minPen, effectiveResist)
+ 	local out = { }
+ 	local resistForm = (damageType == "Physical") and "physical damage reduction" or "resistance"
+ 	local resistLabel = resistForm
+-
+-	if invertChance and invertChance ~= 0 then
+-		resistLabel = "average inverted "..resistForm
++	minPen = minPen or 0
++	local calcPenResist = function(resist)
++		return resist > minPen and m_max(resist - pen, minPen) or resist
+ 	end
++	effectiveResist = effectiveResist or calcPenResist(resist)
++
+ 	if sourceRes and sourceRes ~= damageType then
+ 		t_insert(out, s_format("Enemy %s: %d%% ^8(%s)", resistLabel, resist, sourceRes))
+ 	elseif resist ~= 0 then
+ 		t_insert(out, s_format("Enemy %s: %d%%", resistLabel, resist))
+ 	end
+-	if pen ~= 0 or not useRes then
++	if invertChance and invertChance ~= 0 and useRes then
++		local normalResist = calcPenResist(resist)
++		local invertedResist = calcPenResist(-resist)
++		t_insert(out, "Effective resistance:")
++		t_insert(out, s_format("%g%% ^8(non-inverted hit after penetration)", normalResist))
++		t_insert(out, s_format("%g%% ^8(inverted hit after penetration)", invertedResist))
++		t_insert(out, s_format("= %g%% ^8(weighted average from %.0f%% inversion chance)", effectiveResist, invertChance * 100))
++	elseif pen ~= 0 or not useRes then
+ 		t_insert(out, "Effective resistance:")
+ 		t_insert(out, s_format("%d%% ^8(resistance)", resist))
+ 		if pen < 0 then
+@@ -145,7 +154,7 @@ function breakdown.effMult(damageType, resist, pen, taken, mult, takenMore, sour
+ 	if useRes then
+ 		breakdown.multiChain(out, {
+ 			label = "Effective DPS modifier:",
+-			{ "%.2f ^8(%s)", 1 - (math.max(resist - pen,0)) / 100, resistForm },
++			{ "%.2f ^8(%s)", 1 - effectiveResist / 100, resistForm },
+ 			{ "%.2f ^8(increased/reduced damage taken)", 1 + taken / 100 },
+ 			{ "%.2f ^8(more/less damage taken)", takenMore },
+ 			total = s_format("= %.3f", mult),

src/Modules/CalcOffence.lua.rej

@@ -0,0 +1,54 @@
+diff a/src/Modules/CalcOffence.lua b/src/Modules/CalcOffence.lua	(rejected hunks)
+@@ -4157,11 +4157,7 @@ function calcs.offence(env, actor, activeSkill)
+ 							end
+ 						end
+
+-						local invertChance = m_max(m_min(skillModList:Sum("CHANCE", cfg, "HitsInvertEleResChance"), 1), 0)
+-						if isElemental[damageType] and invertChance > 0 then
+-							-- resist = (1 - invertChance) * resist + invertChance * (-1 * resist)
+-							resist = resist - 2 * invertChance * resist
+-						end
++						local invertChance = isElemental[damageType] and m_max(m_min(skillModList:Sum("CHANCE", cfg, "HitsInvertEleResChance"), 1), 0) or 0
+ 						sourceRes = env.modDB:Flag(nil, "Enemy"..sourceRes.."ResistEqualToYours") and "Your "..sourceRes.." Resistance" or (env.partyMembers.modDB:Flag(nil, "Enemy"..sourceRes.."ResistEqualToYours") and "Party Member "..sourceRes.." Resistance" or sourceRes)
+ 						if skillFlags.projectile then
+ 							takenInc = takenInc + enemyDB:Sum("INC", nil, "ProjectileDamageTaken")
+@@ -4174,10 +4170,20 @@ function calcs.offence(env, actor, activeSkill)
+ 						end
+ 						local effMult = (1 + takenInc / 100) * takenMore
+ 						local useRes = useThisResist(damageType)
++						local effectiveResist = resist
++						local calcPenResist = function(resist)
++							return resist > minPen and m_max(resist - pen, minPen) or resist
++						end
+ 						if skillModList:Flag(cfg, isElemental[damageType] and "CannotElePenIgnore" or nil) then
+-							effMult = effMult * (1 - resist / 100)
++							effectiveResist = (isElemental[damageType] and invertChance > 0) and (resist - 2 * invertChance * resist) or resist
++							effMult = effMult * (1 - effectiveResist / 100)
+ 						elseif useRes then
+-							effMult = effMult * (1 - (resist > minPen and m_max(resist - pen, minPen) or resist) / 100)
++							if isElemental[damageType] and invertChance > 0 then
++								effectiveResist = calcPenResist(resist) * (1 - invertChance) + calcPenResist(-resist) * invertChance
++							else
++								effectiveResist = calcPenResist(resist)
++							end
++							effMult = effMult * (1 - effectiveResist / 100)
+ 						end
+ 						damageTypeHitMin = damageTypeHitMin * effMult
+ 						damageTypeHitMax = damageTypeHitMax * effMult
+@@ -4185,12 +4191,12 @@ function calcs.offence(env, actor, activeSkill)
+ 						if env.mode == "CALCS" then
+ 							output[damageType.."EffMult"] = effMult
+ 						end
+-						if pass == 2 and breakdown and (effMult ~= 1 or sourceRes ~= damageType) and skillModList:Flag(cfg, isElemental[damageType] and "CannotElePenIgnore" or nil) then
++						if pass == 2 and breakdown and (effMult ~= 1 or sourceRes ~= damageType or invertChance > 0) and skillModList:Flag(cfg, isElemental[damageType] and "CannotElePenIgnore" or nil) then
+ 							t_insert(breakdown[damageType], s_format("x %.3f ^8(effective DPS modifier)", effMult))
+-							breakdown[damageType.."EffMult"] = breakdown.effMult(damageType, resist, 0, takenInc, effMult, takenMore, sourceRes, useRes, invertChance, minPen)
+-						elseif pass == 2 and breakdown and (effMult ~= 1 or (resist - pen) < minPen or sourceRes ~= damageType) then
++							breakdown[damageType.."EffMult"] = breakdown.effMult(damageType, resist, 0, takenInc, effMult, takenMore, sourceRes, useRes, invertChance, minPen, effectiveResist)
++						elseif pass == 2 and breakdown and (effMult ~= 1 or (resist - pen) < minPen or sourceRes ~= damageType or invertChance > 0) then
+ 							t_insert(breakdown[damageType], s_format("x %.3f ^8(effective DPS modifier)", effMult))
+-							breakdown[damageType.."EffMult"] = breakdown.effMult(damageType, resist, pen, takenInc, effMult, takenMore, sourceRes, useRes, invertChance, minPen)
++							breakdown[damageType.."EffMult"] = breakdown.effMult(damageType, resist, pen, takenInc, effMult, takenMore, sourceRes, useRes, invertChance, minPen, effectiveResist)
+ 						end
+ 					end
+ 					if pass == 2 and breakdown then