Fix calculation of Bifurcated Crits

spec/System/TestAttacks_spec.lua

@@ -231,6 +231,49 @@ describe("TestAttacks", function()
 		end
 	end)
 
+	it("correctly calculates Garukhan's Resolve bifurcated critical hit damage", function()
+		local function setup(socketGroup)
+			newBuild()
+			build.itemsTab:CreateDisplayItemFromRaw([[
+				New Item
+				Razor Quarterstaff
+				Quality: 0
+				This Weapon's Critical Hit Chance is 0%
+				-100% increased physical damage
+				adds 1 to 1 physical damage to attacks
+				nearby enemies have 100% less armour
+				nearby enemies have 100% less evasion
+			]])
+			build.itemsTab:AddDisplayItem()
+			runCallback("OnFrame")
+			build.skillsTab:PasteSocketGroup(socketGroup)
+			runCallback("OnFrame")
+
+			build.configTab.input.customMods = [[
+				+50% to critical hit chance
+				your critical damage bonus is 1000000%
+				+4000 to accuracy
+			]]
+			build.configTab:BuildModList()
+			runCallback("OnFrame")
+			build.calcsTab:BuildOutput()
+			runCallback("OnFrame")
+
+			return build.calcsTab.mainOutput.MainHand
+		end
+
+		local normalOutput = setup("Quarterstaff Strike 1/0  1")
+		assert.are.equals(50, normalOutput.CritChance)
+		assert.are.equals(10001, normalOutput.CritMultiplier)
+		assert.are.equals(5001, normalOutput.AverageHit)
+
+		local garukhanOutput = setup("Quarterstaff Strike 1/0  1\nGarukhan's Resolve 1/0  1")
+		assert.are.equals(50, garukhanOutput.PreBifurcateCritChance)
+		assert.are.equals(75, garukhanOutput.CritChance)
+		assert.is_true(math.abs(1 / 3 - (garukhanOutput.CritBifurcates - 1)) < 0.000001)
+		assert.is_true(math.abs(10001 - garukhanOutput.AverageHit) < 0.01)
+	end)
+
 	it("correctly adds damage with oracle forced outcome", function()
 		-- Setup: Add weapon with no crit chance, and strip enemy defenses
 		build.itemsTab:CreateDisplayItemFromRaw([[

src/Modules/CalcOffence.lua

@@ -3808,18 +3808,22 @@ function calcs.offence(env, actor, activeSkill)
 					-- get crit chance and calculate odds of critting twice
 					local critChancePercentage = output.PreBifurcateCritChance
 					local bifurcateMultiChance = (critChancePercentage ^ 2) / 100
-					output.CritBifurcates = bifurcateMultiChance
+					local effectiveCritChance = output.CritChance
+					local conditionalBifurcateChance = effectiveCritChance > 0 and bifurcateMultiChance / effectiveCritChance or 0
+					output.CritBifurcates = 1 + conditionalBifurcateChance
 					local damageBonus = extraDamage
-					local bifurcatedBonus = bifurcateMultiChance * extraDamage / 100
-					if breakdown and enemyInc ~= 1 then
+					local bifurcatedBonus = conditionalBifurcateChance * extraDamage
+					if breakdown then
 						breakdown.CritBifurcates = {
-							s_format("%.2f%% ^8(effective crit chance)", critChancePercentage),
+							s_format("%.2f%% ^8(pre-bifurcate crit chance)", critChancePercentage),
 							s_format("x %.2f%%", critChancePercentage),
-							s_format("= %.2f%% ^8(crit Bifurcates chance)", bifurcateMultiChance),
+							s_format("= %.2f%% ^8(chance both crit rolls succeed)", bifurcateMultiChance),
+							s_format("/ %.2f%% ^8(chance at least one crit roll succeeds)", effectiveCritChance),
+							s_format("= %.2f ^8(crit Bifurcates effect)", 1 + conditionalBifurcateChance),
 						}
 					end
 					extraDamage = damageBonus + bifurcatedBonus
-					skillModList:NewMod("CritMultiplier", "MORE", floor(bifurcateMultiChance, 2), "Bifurcated Crit Damage Bonus")
+					skillModList:NewMod("CritMultiplier", "MORE", floor(conditionalBifurcateChance * 100, 2), "Bifurcated Crit Damage Bonus")
 				end
 
 				if env.mode_effective then

src/Modules/CalcSections.lua

@@ -576,7 +576,7 @@ return {
 		{ label = "Player modifiers", modName = { "CritChance", "WeaponBaseCritChance", "MainHandCritIsEqualToParent", "MainHandCritIsEqualToPartyMember", "AttackCritIsEqualToParentMainHand", "InevitableCriticalHits" }, cfg = "weapon1" }, 
 		{ label = "Enemy modifiers", modName = "SelfCritChance", enemy = true }, 
 	}, },
-	{ label = "MH Crit Bifurcates", bgCol = colorCodes.MAINHANDBG, haveOutput = "MainHand.CritBifurcates", flag = "weapon1Attack", { format = "{2:output:MainHand.CritBifurcates}%", 
+	{ label = "MH Crit Bifurcates", bgCol = colorCodes.MAINHANDBG, haveOutput = "MainHand.CritBifurcates", flag = "weapon1Attack", { format = "x {2:output:MainHand.CritBifurcates}", 
 		{ breakdown = "MainHand.CritBifurcates" }, 
 		{ label = "Player modifiers", modName = "BifurcateCrit", cfg = "weapon1" },
 	}, },
@@ -596,7 +596,7 @@ return {
 		{ label = "Player modifiers", modName = { "CritChance", "WeaponBaseCritChance", "AttackCritIsEqualToParentMainHand", "InevitableCriticalHits" }, cfg = "weapon2" },
 		{ label = "Enemy modifiers", modName = "SelfCritChance", enemy = true }, 
 	}, },
-	{ label = "OH Crit Bifurcates", bgCol = colorCodes.OFFHANDBG, haveOutput = "OffHand.CritBifurcates", flag = "weapon2Attack", { format = "{2:output:OffHand.CritBifurcates}%", 
+	{ label = "OH Crit Bifurcates", bgCol = colorCodes.OFFHANDBG, haveOutput = "OffHand.CritBifurcates", flag = "weapon2Attack", { format = "x {2:output:OffHand.CritBifurcates}", 
 		{ breakdown = "OffHand.CritBifurcates" }, 
 		{ label = "Player modifiers", modName = "BifurcateCrit", cfg = "weapon2" },
 	}, },