overengineer entityimpl a bit more

src/deathpart.c

@@ -3,25 +3,6 @@
 #include "entityimpl.h"
 #include <stdlib.h>
 
-IMPL_UPDATE() {
-	if (this->deathpart.skip == 0) {
-		this->vel[1] *= AIR_RESISTANCE;
-		this->vel[1] += GRAVITY;
-		entity_move(this, g);
-		this->deathpart.skip = 3;
-	} else
-		this->deathpart.skip -= 1;
-} IMPL_END
-
-IMPL_DRAW() {
-	LZY_DrawSetColor(BLACK);
-	if (this->width == 1)
-		(void)LZY_DrawPoint(this->pos[0], this->pos[1]);
-	else
-		(void)LZY_DrawRect(this->pos[0], this->pos[1],
-		                   this->width, this->width);
-} IMPL_END
-
 IMPL_INIT(deathpart) {
 	this->ignore_solids = true;
 	this->vel[0] = (float)(rand() % 1024) / 1024;
@@ -30,4 +11,23 @@ IMPL_INIT(deathpart) {
 	if (rand() % 2)
 		this->vel[0] *= -1;
 	this->width = 1 + rand() % 2;
-} IMPL_END
+}
+
+IMPL(update) {
+	if (this->deathpart.skip == 0) {
+		this->vel[1] *= AIR_RESISTANCE;
+		this->vel[1] += GRAVITY;
+		entity_move(this, g);
+		this->deathpart.skip = 3;
+	} else
+		this->deathpart.skip -= 1;
+}
+
+IMPL(draw) {
+	LZY_DrawSetColor(BLACK);
+	if (this->width == 1)
+		(void)LZY_DrawPoint(this->pos[0], this->pos[1]);
+	else
+		(void)LZY_DrawRect(this->pos[0], this->pos[1],
+		                   this->width, this->width);
+}

src/entity.c

@@ -20,7 +20,7 @@ unsigned int
 entity_type(const char *type)
 {
 	for (unsigned int i = 0; i < num_entitytags; i++)
-		if (strcmp(type, entitytags[i]) == 0)
+		if (strcmp(type, entitytags[i].name) == 0)
 			return i + 1;
 	fprintf(stderr, "unknown type '%s'\n", type);
 	return 0;
@@ -100,5 +100,6 @@ entity_move(Entity *this, Game *g)
 Entity *
 entity_init(Entity *this, unsigned int type, int x, int y)
 {
-	return entityinits[type - 1](this, x, y);
+	entitytags[type - 1].init(this, x, y);
+	return this;
 }

src/entity.h

@@ -11,8 +11,8 @@ enum { ET_NONE = 0 };
 typedef struct Entity Entity;
 struct Entity {
 	unsigned long uuid;
-	Entity *(*update)(Entity *this, struct Game *g);
-	Entity *(*draw)(Entity *this, struct Game *g);
+	void (*update)(Entity *this, struct Game *g);
+	void (*draw)(Entity *this, struct Game *g);
 	unsigned int type;
 	int id;
 	int pos[2];

src/entityimpl.h

@@ -5,25 +5,26 @@
 #include "entitytag.h"
 #include <string.h>
 
-#define IMPL_UPDATE() static Entity * \
-update([[maybe_unused]] Entity *this, [[maybe_unused]] Game *g) {
+[[maybe_unused]] static void *_draw;
+[[maybe_unused]] static void *_update;
 
-#define IMPL_DRAW() static Entity * \
-draw([[maybe_unused]] Entity *this, [[maybe_unused]] Game *g) {
+#define IMPL(X) static void X(Entity *this, Game *g); \
+__attribute__((constructor)) static void init_##X() { _##X = X; } \
+static void X([[maybe_unused]] Entity *this, [[maybe_unused]] Game *g)
 
-#define IMPL_INIT(X) static Entity *init(Entity *this, int x, int y); \
+#define IMPL_INIT(X) static void init(Entity *this, int x, int y); \
 __attribute__((constructor)) static void init_tag() { \
-	entityinits[num_entitytags] = init; \
-	entitytags[num_entitytags++] = #X; \
+	entitytags[num_entitytags].init = init; \
+	entitytags[num_entitytags++].name = #X; \
 } \
-static Entity * \
-init(Entity *this, int x, int y) { do { \
+static void _init(Entity *this); \
+static void init(Entity *this, int x, int y) { \
 	memset(this, 0, sizeof(*this)); \
-	this->update = update; \
-	this->draw = draw; \
+	this->update = _update; \
+	this->draw = _draw; \
 	this->pos[0] = x; \
 	this->pos[1] = y; \
 	this->type = entity_type(#X); \
-} while(0);
-
-#define IMPL_END return this; }
+	_init(this); \
+} \
+static void _init([[maybe_unused]] Entity *this)

src/entitytag.c

@@ -1,5 +1,4 @@
 #include "entitytag.h"
 
 unsigned int num_entitytags = 0;
-const char *entitytags[256] = {};
-EntityInit entityinits[256] = {};
+EntityTag entitytags[256] = {};

src/entitytag.h

@@ -1,7 +1,10 @@
 #pragma once
 #include "entity.h"
 
-typedef Entity *(*EntityInit)(Entity *this, int x, int y);
+typedef struct {
+	const char *name;
+	void (*init)(Entity *this, int x, int y);
+} EntityTag;
+
 extern unsigned int num_entitytags;
-extern const char *entitytags[256];
-extern EntityInit entityinits[256];
+extern EntityTag entitytags[256];

src/exit.c

@@ -1,17 +1,14 @@
 #include "entityimpl.h"
 #include "rotrect.h"
 
-IMPL_UPDATE() {
-} IMPL_END
-
-IMPL_DRAW() {
-	LZY_DrawSetColor(BLACK);
-	rotrect(this->pos[0], this->pos[1],
-	        this->width, this->height, 0.2 * this->exit.dir);
-} IMPL_END
-
 IMPL_INIT(exit) {
 	this->width = 12;
 	this->height = 12;
 	this->exit.dir = 1;
-} IMPL_END
+}
+
+IMPL(draw) {
+	LZY_DrawSetColor(BLACK);
+	rotrect(this->pos[0], this->pos[1],
+	        this->width, this->height, 0.2 * this->exit.dir);
+}

src/player.c

@@ -5,7 +5,23 @@
 #include "rotrect.h"
 #include <math.h>
 
-IMPL_UPDATE() {
+IMPL_INIT(player) {
+	this->width = 10;
+	this->height = 10;
+	this->player.scale_x = 1.0;
+	this->player.scale_y = 1.0;
+	this->player.dirx = 1;
+}
+
+IMPL(draw) {
+	LZY_DrawSetColor(BLACK);
+	const double width = this->width * this->player.scale_x + 2;
+	const double height = this->height * this->player.scale_y + 2;
+	rotrect(this->pos[0] - 1, this->pos[1] - 1,
+	        width, height, this->player.angle);
+}
+
+IMPL(update) {
 	const int on_ground = entity_collide(this, g, 0, 1);
 
 	this->vel[0] = 2.0 * this->player.dirx;
@@ -71,20 +87,4 @@ IMPL_UPDATE() {
 
 	if (entity_place_meeting(this, g, entity_type("exit")) != NULL)
 		g->queue_next_scene = true;
-} IMPL_END
-
-IMPL_DRAW() {
-	LZY_DrawSetColor(BLACK);
-	const double width = this->width * this->player.scale_x + 2;
-	const double height = this->height * this->player.scale_y + 2;
-	rotrect(this->pos[0] - 1, this->pos[1] - 1,
-	        width, height, this->player.angle);
-} IMPL_END
-
-IMPL_INIT(player) {
-	this->width = 10;
-	this->height = 10;
-	this->player.scale_x = 1.0;
-	this->player.scale_y = 1.0;
-	this->player.dirx = 1;
-} IMPL_END
+}

src/spike.c

@@ -1,14 +1,11 @@
 #include "entityimpl.h"
 #include "rotrect.h"
 
-IMPL_UPDATE() {
-} IMPL_END
-
-IMPL_DRAW() {
-	rotrect_draw(g->spike_rect, this->pos[0], this->pos[1]);
-	rotrect_draw(g->spike_irect, this->pos[0], this->pos[1]);
-} IMPL_END
-
 IMPL_INIT(spike) {
 	this->height = this->width = 8;
-} IMPL_END
+}
+
+IMPL(draw) {
+	rotrect_draw(g->spike_rect, this->pos[0], this->pos[1]);
+	rotrect_draw(g->spike_irect, this->pos[0], this->pos[1]);
+}