From 34f484b8bfeb4572a224def19d1484ae058645e0 Mon Sep 17 00:00:00 2001
From: quou <quou@disroot.org>
Date: Wed, 26 Mar 2025 20:23:36 +1100
Subject: stretchy component pools

---
 world.hpp | 38 ++++++++++++++++++++++++++++++--------
 1 file changed, 30 insertions(+), 8 deletions(-)

(limited to 'world.hpp')

diff --git a/world.hpp b/world.hpp
index 267b58a..a45cf9c 100644
--- a/world.hpp
+++ b/world.hpp
@@ -12,19 +12,35 @@ using Component_Mask = uint64_t;
 using Entity_Id = uint32_t;
 
 #define max_entities 1024
-#define pool_cap 128
+#define slinky_size 128
 #define max_components 64
+#define max_slinkies (max_entities / slinky_size)
+
+struct Slinky {
+	Entity_Id* entities;
+	void* data;
+	int count;
+
+	void init(Arena* a, int size);
+	void* add(Entity_Id eid, int size, int& mapping);
+	void* get(Entity_Id eid, int mapping, int size);
+	void remove(Entity_Id eid, int mapping, int size);
+};
 
 struct Pool {
+	struct Mapping {
+		int slinky;
+		int mapping;
+	};
+
 	Component_Mask mask;
-	Pool* next;
-	void* data;
-	Entity_Id entities[pool_cap];
-	int mapping[max_entities];
+	Slinky slinkies[max_slinkies];
+	Mapping mapping[max_entities];
 	int offsets[max_components];
-	int size, count;
+	int size, count, slinky_count;
 
 	void init(Arena* a, Component_Mask m);
+	Slinky& get_slinky(Arena* a);
 	void* add(Arena* a, Entity_Id eid);
 	void* get(Entity_Id eid, int cid);
 	void* get(Entity_Id eid);
@@ -126,8 +142,11 @@ struct World {
 			template <typename C>
 			C& get() {
 				Pool* p = v->pools[ind];
+				Slinky& s = p->slinkies[ptr / slinky_size];
+				int si = &s - p->slinkies;
+				int off = ptr - (si * slinky_size);
 				return *(C*)(
-					(char*)p->data + ptr * p->size +
+					(char*)s.data + off * p->size +
 					p->offsets[v->w->get_component_id<C>()]
 				);
 			}
@@ -138,7 +157,10 @@ struct World {
 
 			Entity_Id entity() {
 				Pool* p = v->pools[ind];
-				return p->entities[ptr];
+				Slinky& s = p->slinkies[ptr / slinky_size];
+				int si = &s - p->slinkies;
+				int off = ptr - (si * slinky_size);
+				return s.entities[off];
 			}
 		};
 
-- 
cgit v1.2.3-54-g00ecf