game: minimal implementation of SP_target_camera

Based on:
 * https://github.com/id-Software/quake2-rerelease-dll/blob/main/rerelease/g_target.cpp

README.md

@@ -150,6 +150,10 @@ Goals:
 * [x] RGB particles support instead palette based one,
 * [x] Get rid of VID_PaletteColor client internal api use,
 * [x] Broken maps groups from base2 to next,
+* [ ] Group `it_pic` images in vulkan render,
+* [ ] Rearange surfaces in vulkan render before render,
+* [ ] Fully implement `target_camera`,
+* [ ] Fully implement `misc_flare`,
 * [ ] Single player ReRelease support,
 * [ ] Support effects and additional flags for ReRelease when possible.
 * [ ] Use shared model cache in client code insted reimplemnet in each render,

src/client/cl_tempentities.c

@@ -864,6 +864,7 @@ CL_ParseTEnt(void)
 			break;
 
 		case TE_RAILTRAIL: /* railgun effect */
+		case TE_RAILTRAIL2:
 			MSG_ReadPos(&net_message, pos);
 			MSG_ReadPos(&net_message, pos2);
 			CL_RailTrail(pos, pos2);

src/game/g_target.c

@@ -1474,6 +1474,55 @@ SP_target_earthquake(edict_t *self)
 	}
 }
 
+/*
+ * QUAKED target_camera (1 0 0) (-8 -8 -8) (8 8 8)
+ * [Sam-KEX] Creates a camera path as seen in the N64 version.
+*/
+void
+use_target_camera(edict_t *self, edict_t *other, edict_t *activator)
+{
+	edict_t *target;
+
+	if (!self)
+	{
+		return;
+	}
+
+	if (self->sounds)
+	{
+		gi.configstring(CS_CDTRACK, va("%i", self->sounds));
+	}
+
+	if (!self->killtarget)
+	{
+		return;
+	}
+
+	target = G_PickTarget(self->killtarget);
+
+	if (!target || !target->use)
+	{
+		return;
+	}
+
+	/* TODO: Fully implement target camera logic */
+	target->use(target, self, activator);
+}
+
+void
+SP_target_camera(edict_t* self)
+{
+	if (deathmatch->value)
+	{
+		/* auto-remove for deathmatch */
+		G_FreeEdict(self);
+		return;
+	}
+
+	self->use = use_target_camera;
+	self->svflags = SVF_NOCLIENT;
+}
+
 /*
  * QUAKED target_gravity (1 0 0) (-8 -8 -8) (8 8 8) NOTRAIL NOEFFECTS
  * [Sam-KEX] Changes gravity, as seen in the N64 version

src/game/savegame/tables/gamefunc_decs.h

@@ -1434,6 +1434,7 @@ extern void use_killbox ( edict_t * self , edict_t * other , edict_t * activator
 extern void use_nuke ( edict_t * self , edict_t * other , edict_t * activator ) ;
 extern void use_scanner ( edict_t * self ) ;
 extern void use_target_blaster ( edict_t * self , edict_t * other , edict_t * activator ) ;
+extern void use_target_camera ( edict_t * self , edict_t * other , edict_t * activator);
 extern void use_target_changelevel ( edict_t * self , edict_t * other , edict_t * activator ) ;
 extern void use_target_explosion ( edict_t * self , edict_t * other , edict_t * activator ) ;
 extern void use_target_goal ( edict_t * ent , edict_t * other , edict_t * activator ) ;

src/game/savegame/tables/gamefunc_list.h

@@ -1430,6 +1430,7 @@
 {"use_nuke", (byte *)use_nuke},
 {"use_scanner", (byte *)use_scanner},
 {"use_target_blaster", (byte *)use_target_blaster},
+{"use_target_camera", (byte *)use_target_camera},
 {"use_target_changelevel", (byte *)use_target_changelevel},
 {"use_target_explosion", (byte *)use_target_explosion},
 {"use_target_goal", (byte *)use_target_goal},

src/game/savegame/tables/spawnfunc_decs.h

@@ -162,6 +162,7 @@ extern void SP_target_actor(edict_t * self);
 extern void SP_target_anger(edict_t * self);
 extern void SP_target_blacklight ( edict_t * ent ) ;
 extern void SP_target_blaster(edict_t * self);
+extern void SP_target_camera(edict_t* self);
 extern void SP_target_changelevel ( edict_t * ent ) ;
 extern void SP_target_character(edict_t * self);
 extern void SP_target_crosslevel_target(edict_t * self);

src/game/savegame/tables/spawnfunc_list.h

@@ -168,6 +168,7 @@
 {"target_anger", SP_target_anger},
 {"target_blacklight", SP_target_blacklight},
 {"target_blaster", SP_target_blaster},
+{"target_camera", SP_target_camera},
 {"target_changelevel", SP_target_changelevel},
 {"target_character", SP_target_character},
 {"target_crosslevel_target", SP_target_crosslevel_target},