From: Lukas Krickl <lukas@krickl.dev>
Date: Fri, 22 Aug 2025 12:35:17 +0000 (+0200)
Subject: stats: Added basic damage calculation
X-Git-Url: https://git.krickl.dev/?a=commitdiff_plain;h=b3af087214f1a7dc032e2e3b03d721e69ec55616;p=gbrg%2F.git

stats: Added basic damage calculation
---

diff --git a/src/macros.inc b/src/macros.inc
index 808b29c..43b33fd 100644
--- a/src/macros.inc
+++ b/src/macros.inc
@@ -265,3 +265,17 @@
 #macro farcall
   rst 0x10
 #endmacro
+	
+	; subtracts b-a
+	; inputs:
+	;		a, b
+	;	returns:
+	;		b: thew new value
+	;	uses:
+	;		c, a, b
+#macro sub_ba
+	ld c, a 
+	ld a, b
+	sub a, c
+	ld b, a
+#endmacro
diff --git a/src/stats.s b/src/stats.s
index acc6263..fbeccb0 100644
--- a/src/stats.s
+++ b/src/stats.s
@@ -64,6 +64,8 @@ stat_calc_hp_max:
 	
 	; calculates physical damage of 
 	; one actor agains another
+	; formula:
+	;		physical damage = (weapon damage a1 + strength a1 / 8) - (ac a2 / 2)
 	; inputs:
 	;		de: actor1
 	;		bc: actor2
@@ -71,19 +73,52 @@ stat_calc_hp_max:
 	;		sub damage from actor2
 	;		a: damage
 stat_calc_physical_damage_vs:
+	; actor 1
+
 	call stat_calc_weapon_damage
 	; a = damage
-	push bc
-	pop de ; de = actor2 now
 	ld b, a ; b = weapon damage
 
+	; weapon damage + strenth / 8
+	call stat_calc_str
+	sla a ; / 2
+	sla a ; / 4
+	sla a ; / 8
+	add a, b
+	ld b, a ; b = real damage
+
+	; actor 2
+	
+	push bc
+	pop de ; de = actor2 now
+	; damage - ac/2
 	call stat_calc_ac
+	sla a
+	sub_ba
+	jp c, @no_damage
 
+	; b = damage to apply
+
+	; apply damage
+
+	ld hl, act_hp
+	add hl, de
+	; hl = act2 hp
+	ld a, [hl]
+	sub a, b
+	jp c, @dead
+
+	; write new hp
+	ld [hl], a
 
 	ret
 @no_damage:
 	xor a, a
 	ret
+@dead:
+	xor a, a
+	ld [hl], a ; write 0 hp
+	ret
 
   ; calculates the real speed state
   ; inputs: