From 8763c437b3d6a57537c25ff65d7bc3801a7ecca7 Mon Sep 17 00:00:00 2001
From: Camden Dixie O'Brien <cdo@wip.sh>
Date: Sat, 4 Jan 2025 06:13:33 +0000
Subject: [PATCH] Add tag and prev, next pointers to entity structs

---
 game/main.c | 31 +++++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 8 deletions(-)

diff --git a/game/main.c b/game/main.c
index 9117bde..a033d6e 100644
--- a/game/main.c
+++ b/game/main.c
@@ -79,7 +79,19 @@ typedef struct {
 	dvec_t off, ext;
 } dbox_t;
 
+typedef enum {
+	ENTITY_DYN,
+	ENTITY_OBJ,
+} entitytag_t;
+
+typedef struct entity {
+	entitytag_t tag;
+	struct entity *prev;
+	struct entity *next;
+} entity_t;
+
 typedef struct {
+	entity_t e;
 	int svar, animlen;
 	double speed;
 	dvec_t pos, dir;
@@ -95,6 +107,7 @@ typedef struct {
 } objtype_t;
 
 typedef struct {
+	entity_t e;
 	unsigned type;
 	ivec_t pos;
 } objentity_t;
@@ -142,7 +155,7 @@ map_tile(const map_t map, int layeridx, double x, double y)
 		return map[layeridx][row][col];
 }
 
-static inline int propint(xmlNodePtr node, const char *prop)
+static inline int prop_int(xmlNodePtr node, const char *prop)
 {
 	xmlChar *str = xmlGetProp(node, (const xmlChar *)prop);
 	assert(str);
@@ -165,8 +178,8 @@ static void load_layer(map_t map, xmlNodePtr layernode, int layeridx)
 		if (0 != xmlStrcmp(node->name, (const xmlChar *)"chunk"))
 			continue;
 
-		const int chunk_x = propint(node, "x");
-		const int chunk_y = propint(node, "y");
+		const int chunk_x = prop_int(node, "x");
+		const int chunk_y = prop_int(node, "y");
 
 		chunk_contents = node->xmlChildrenNode;
 		assert(
@@ -227,15 +240,15 @@ load_objtype(gamestate_t *state, const char *templ, SDL_Renderer *renderer)
 	       && xmlStrcmp(node->name, (const xmlChar *)"object") != 0)
 		node = node->next;
 	assert(NULL != node);
-	unsigned id = propint(node, "gid");
+	unsigned id = prop_int(node, "gid");
 	assert(id < MAXOBJTYPES);
 
 	// Populate objtype struct if not already loaded
 	if (NULL == state->objtypes[id].tex) {
 		state->objtypes[id].src.x = 0;
 		state->objtypes[id].src.y = 0;
-		state->objtypes[id].src.w = propint(node, "width");
-		state->objtypes[id].src.h = propint(node, "height");
+		state->objtypes[id].src.w = prop_int(node, "width");
+		state->objtypes[id].src.h = prop_int(node, "height");
 
 		node = node->xmlChildrenNode;
 		while (node != NULL
@@ -293,6 +306,7 @@ load_objects(gamestate_t *state, xmlNodePtr node, SDL_Renderer *renderer)
 			assert(state->objcol.buf);
 		}
 		objentity_t *o = &state->objcol.buf[state->objcol.n++];
+		o->e.tag = ENTITY_OBJ;
 
 		// Load object type
 		xmlChar *templ = xmlGetProp(node, (const xmlChar *)"template");
@@ -301,8 +315,8 @@ load_objects(gamestate_t *state, xmlNodePtr node, SDL_Renderer *renderer)
 		xmlFree(templ);
 
 		// Load object location
-		o->pos.x = propint(node, "x");
-		o->pos.y = propint(node, "y");
+		o->pos.x = prop_int(node, "x");
+		o->pos.y = prop_int(node, "y");
 	} while ((node = node->next) != NULL);
 }
 
@@ -363,6 +377,7 @@ void game_init(int argc, char *argv[], void *mem, SDL_Renderer *renderer)
 	state->vpos.y = -96;
 
 	// Initialize player state
+	state->p.e.tag = ENTITY_DYN;
 	state->p.svar = SPRITE_DIR_DOWN;
 	state->p.animlen = PANIMLEN;
 	state->p.animstep.x = PWIDTH;