pushies.

code/__DEFINES/_flags/_flags.dm

@@ -64,6 +64,8 @@ GLOBAL_LIST_INIT(bitflags, list(
 #define NO_RUINS_1 (1<<10)
 /// Should this tile be cleaned up and reinserted into an excited group?
 #define EXCITED_CLEANUP_1 (1 << 13)
+/// Whether or not this atom has contextual screentips when hovered OVER
+#define HAS_CONTEXTUAL_SCREENTIPS_1 (1 << 14)
 
 ////////////////Area flags\\\\\\\\\\\\\\
 /// If it's a valid territory for cult summoning or the CRAB-17 phone to spawn

code/__DEFINES/_flags/obj_flags.dm

@@ -17,6 +17,8 @@
 #define EXAMINE_SKIP			(1<<14) /// Makes the Examine proc not read out this item.
 #define IN_STORAGE				(1<<15) //is this item in the storage item, such as backpack? used for tooltips
 #define HAND_ITEM               (1<<16) // If an item is just your hand (circled hand, slapper) and shouldn't block things like riding
+/// Has contextual screentips when HOVERING OVER OTHER objects
+#define ITEM_HAS_CONTEXTUAL_SCREENTIPS (1 << 17)
 
 /// Integrity defines for clothing (not flags but close enough)
 #define CLOTHING_PRISTINE	0 // We have no damage on the clothing

code/__DEFINES/dcs/signals/signals_screentips.dm

@@ -0,0 +1,23 @@
+/// A "Type-A" contextual screentip interaction.
+/// These are used for items that are defined by their behavior. They define their contextual text within *themselves*,
+/// not in their targets.
+/// Examples include syringes (LMB to inject, RMB to draw) and health analyzers (LMB to scan health/wounds, RMB for chems)
+/// Items can override `add_item_context()`, and call `register_item_context()` in order to easily connect to this.
+/// Called on /obj/item with a mutable screentip context list, the hovered target, and the mob hovering.
+/// A screentip context list is a list that has context keys (SCREENTIP_CONTEXT_*, from __DEFINES/screentips.dm)
+/// that map to the action as text.
+/// If you mutate the list in this signal, you must return CONTEXTUAL_SCREENTIP_SET.
+#define COMSIG_ITEM_REQUESTING_CONTEXT_FOR_TARGET "item_requesting_context_for_target"
+
+/// A "Type-B" contextual screentip interaction.
+/// These are atoms that are defined by what happens *to* them. These should define contextual text within themselves, and
+/// not in their operating tools.
+/// Examples include construction objects (LMB with glass to put in screen for computers).
+/// Called on /atom with a mutable screentip context list, the item being used, and the mob hovering.
+/// A screentip context list is a list that has context keys (SCREENTIP_CONTEXT_*, from __DEFINES/screentips.dm)
+/// that map to the action as text.
+/// If you mutate the list in this signal, you must return CONTEXTUAL_SCREENTIP_SET.
+#define COMSIG_ATOM_REQUESTING_CONTEXT_FROM_ITEM "atom_requesting_context_from_item"
+
+/// Tells the contextual screentips system that the list context was mutated.
+#define CONTEXTUAL_SCREENTIP_SET (1 << 0)

code/__DEFINES/screentips.dm

@@ -0,0 +1,17 @@
+/// Context applied to LMB actions
+#define SCREENTIP_CONTEXT_LMB "LMB"
+
+/// Context applied to RMB actions
+#define SCREENTIP_CONTEXT_RMB "RMB"
+
+/// Context applied to Ctrl-LMB actions
+#define SCREENTIP_CONTEXT_CTRL_LMB "Ctrl-LMB"
+
+/// Screentips are always disabled
+#define SCREENTIP_PREFERENCE_DISABLED "Disabled"
+
+/// Screentips are always enabled
+#define SCREENTIP_PREFERENCE_ENABLED "Enabled"
+
+/// Screentips are only enabled when they have context
+#define SCREENTIP_PREFERENCE_CONTEXT_ONLY "Only with tips"