From e6182709d19765b4e25cf2329f5a8ecf2068bd3c Mon Sep 17 00:00:00 2001
From: staphen <staphen@gmail.com>
Date: Sun, 3 Apr 2022 15:10:27 -0400
Subject: [PATCH] Allow casting Town Portal, Teleport, and Guardian scrolls
 from inventory

---
 Source/controls/plrctrls.cpp | 35 ++++++++++++++++++++++++-----------
 Source/items.cpp             | 17 ++++-------------
 Source/spells.cpp            | 10 ++++++++++
 Source/spells.h              |  1 +
 4 files changed, 39 insertions(+), 24 deletions(-)

diff --git a/Source/controls/plrctrls.cpp b/Source/controls/plrctrls.cpp
index 377934020..c5722ae3f 100644
--- a/Source/controls/plrctrls.cpp
+++ b/Source/controls/plrctrls.cpp
@@ -1768,7 +1768,7 @@ bool SpellHasActorTarget()
 	return pcursplr != -1 || pcursmonst != -1;
 }
 
-void UpdateSpellTarget()
+void UpdateSpellTarget(spell_id spell)
 {
 	if (SpellHasActorTarget())
 		return;
@@ -1778,7 +1778,7 @@ void UpdateSpellTarget()
 
 	auto &myPlayer = Players[MyPlayerId];
 
-	int range = myPlayer._pRSpell == SPL_TELEPORT ? 4 : 1;
+	int range = spell == SPL_TELEPORT ? 4 : 1;
 
 	cursPosition = myPlayer.position.future + Displacement(myPlayer._pdir) * range;
 }
@@ -1861,39 +1861,52 @@ void PerformSpellAction()
 		return;
 	}
 
-	UpdateSpellTarget();
+	UpdateSpellTarget(myPlayer._pRSpell);
 	CheckPlrSpell(false);
 }
 
 void CtrlUseInvItem()
 {
-	if (pcursinvitem == -1)
+	if (pcursinvitem == -1) {
 		return;
+	}
 
 	auto &myPlayer = Players[MyPlayerId];
-
 	Item &item = GetInventoryItem(myPlayer, pcursinvitem);
-	if (item.IsScroll() && spelldata[item._iSpell].sTargeted) {
-		return;
+	if (item.IsScroll()) {
+		if (TargetsMonster(item._iSpell)) {
+			return;
+		}
+		if (spelldata[item._iSpell].sTargeted) {
+			UpdateSpellTarget(item._iSpell);
+		}
 	}
+
 	int itemId = GetItemIdOnSlot(Slot);
 	if (item.isEquipment()) {
 		CheckInvItem(true, false); // auto-equip if it's an equipment
 	} else {
 		UseInvItem(MyPlayerId, pcursinvitem);
 	}
-	if (itemId != GetItemIdOnSlot(Slot))
+	if (itemId != GetItemIdOnSlot(Slot)) {
 		ResetInvCursorPosition();
+	}
 }
 
 void CtrlUseStashItem()
 {
-	if (pcursstashitem == uint16_t(-1))
+	if (pcursstashitem == uint16_t(-1)) {
 		return;
+	}
 
 	const Item &item = Stash.stashList[pcursstashitem];
-	if (item.IsScroll() && spelldata[item._iSpell].sTargeted) {
-		return;
+	if (item.IsScroll()) {
+		if (TargetsMonster(item._iSpell)) {
+			return;
+		}
+		if (spelldata[item._iSpell].sTargeted) {
+			UpdateSpellTarget(item._iSpell);
+		}
 	}
 
 	if (item.isEquipment()) {
diff --git a/Source/items.cpp b/Source/items.cpp
index 62e7f6e0c..cd3580aed 100644
--- a/Source/items.cpp
+++ b/Source/items.cpp
@@ -1810,10 +1810,7 @@ void PrintItemMisc(const Item &item)
 		if (ControlMode == ControlTypes::KeyboardAndMouse) {
 			AddPanelString(_("Right-click to read"));
 		} else {
-			if (item.IsScrollOf(SPL_TELEPORT) || item.IsScrollOf(SPL_TOWN)) {
-				AddPanelString(_("Select from spell book, then"));
-				AddPanelString(_("cast spell to read"));
-			} else if (!invflag) {
+			if (!invflag) {
 				AddPanelString(_("Open inventory to use"));
 			} else {
 				AddPanelString(_("Activate to read"));
@@ -1825,13 +1822,7 @@ void PrintItemMisc(const Item &item)
 			AddPanelString(_("Right-click to read, then"));
 			AddPanelString(_("left-click to target"));
 		} else {
-			if (item.IsScrollOf(SPL_FIREBALL)
-			    || item.IsScrollOf(SPL_FIREWALL)
-			    || item.IsScrollOf(SPL_FLAME)
-			    || item.IsScrollOf(SPL_GUARDIAN)
-			    || item.IsScrollOf(SPL_LIGHTNING)
-			    || item.IsScrollOf(SPL_STONE)
-			    || item.IsScrollOf(SPL_WAVE)) {
+			if (TargetsMonster(item._iSpell)) {
 				AddPanelString(_("Select from spell book, then"));
 				AddPanelString(_("cast spell to read"));
 			} else if (!invflag) {
@@ -3932,7 +3923,7 @@ void UseItem(int pnum, item_misc_id mid, spell_id spl)
 		}
 		break;
 	case IMISC_SCROLL:
-		if (spelldata[spl].sTargeted) {
+		if (ControlMode == ControlTypes::KeyboardAndMouse && spelldata[spl].sTargeted) {
 			player._pTSpell = spl;
 			if (pnum == MyPlayerId)
 				NewCursor(CURSOR_TELEPORT);
@@ -3949,7 +3940,7 @@ void UseItem(int pnum, item_misc_id mid, spell_id spl)
 		}
 		break;
 	case IMISC_SCROLLT:
-		if (spelldata[spl].sTargeted) {
+		if (ControlMode == ControlTypes::KeyboardAndMouse && spelldata[spl].sTargeted) {
 			player._pTSpell = spl;
 			if (pnum == MyPlayerId)
 				NewCursor(CURSOR_TELEPORT);
diff --git a/Source/spells.cpp b/Source/spells.cpp
index 01a3dfb9e..65639475a 100644
--- a/Source/spells.cpp
+++ b/Source/spells.cpp
@@ -113,6 +113,16 @@ bool IsWallSpell(spell_id spl)
 	return spl == SPL_FIREWALL || spl == SPL_LIGHTWALL;
 }
 
+bool TargetsMonster(spell_id id)
+{
+	return id == SPL_FIREBALL
+	    || id == SPL_FIREWALL
+	    || id == SPL_FLAME
+	    || id == SPL_LIGHTNING
+	    || id == SPL_STONE
+	    || id == SPL_WAVE;
+}
+
 int GetManaAmount(Player &player, spell_id sn)
 {
 	int ma; // mana amount
diff --git a/Source/spells.h b/Source/spells.h
index 53806297c..821f4bde2 100644
--- a/Source/spells.h
+++ b/Source/spells.h
@@ -17,6 +17,7 @@ enum class SpellCheckResult : uint8_t {
 };
 
 bool IsWallSpell(spell_id spl);
+bool TargetsMonster(spell_id id);
 int GetManaAmount(Player &player, spell_id sn);
 void UseMana(int id, spell_id sn);
 SpellCheckResult CheckSpell(int id, spell_id sn, spell_type st, bool manaonly);