Add Y distance check to business Deku Scrub talk

ASM/ootSymbols.ld

@@ -18,6 +18,7 @@ Flags_GetCollectible = 0x800206E8;
 Flags_SetCollectible = 0x8002071C;
 Actor_SetColorFilter = 0x80027090;
 CutsceneFlags_Get = 0x8005991C;
+Math_SmoothStepToS = 0x80064508;
 z64_Gfx_SetupDL_42Opa = 0x8007E868;
 Audio_StopCurrentMusic = 0x800C7684;
 sprintf = 0x800CE7b4;

ASM/src/build.asm

@@ -133,6 +133,7 @@ RANDO_CONTEXT:
 .include "en_dns.asm"
 .include "bg_gate_shutter.asm"
 .include "big_poe.asm"
+.include "endns_checkydist.asm"
 
 .align 0x10
 .importobj "../build/bundle.o"

ASM/src/endns_checkydist.asm

@@ -0,0 +1,19 @@
+EnDns_CheckYDist:
+    addiu   sp,sp,-24
+    sw      ra,16(sp)
+    jal     Math_SmoothStepToS  ; displaced call
+    li      a3,2000
+
+    lui     at,0x42c8           ; 100.0f
+    mtc1    at,$f4              ; Load 100.0f to float register
+    lwc1    $f0,148(s0)         ; EnDns Y distance to player
+    abs.s   $f0,$f0             ; Absolute EnDns-player Y distance
+    c.lt.s  $f0,$f4             ; Y distance < 100.0f?
+    bc1tl   @@Return            ; If yes, continue function
+    li      v0,1
+    li      v0,0                ; Else, to return in caller
+@@Return:
+    lh      t6,182(s0)          ; displaced
+    lw      ra,16(sp)
+    jr      ra
+    addiu   sp,sp,24

ASM/src/hacks/ovl_en_dns.asm

@@ -1,4 +1,4 @@
-; Hacks in en_dns (deku scrub salesman)
+; Hacks in en_dns (friendly Deku Scrub salesman)
 .headersize(0x80A74C60 - 0x00DF75A0)
 
 ; Hack EnDns_SetupSale to take the payment before giving the item
@@ -16,3 +16,17 @@
 
 .org 0x80a7590c
     nop
+
+;================================================================================
+; Adds Y distance check to talking with business Deku Scrub (prevents buying in
+; MQ Deku Tree from the water, but not being able to get the item)
+;================================================================================
+; Replaces jal     Math_SmoothStepToS
+;          li      a3,2000
+;          lh      t6,182(s0)
+;          move    a0,s0
+.org 0x80a754fc                 ; in EnDns_Idle
+    jal     EnDns_CheckYDist
+    nop
+    beqz    v0,0x80a75598       ; EnDns_Idle function return
+    move    a0,s0               ; displaced