place_meeting

2 files changed, 35 insertions, 4 deletions

diff --git a/src/entity.c b/src/entity.c
index fc45e2a..001b9e1 100644
--- a/src/entity.c
+++ b/src/entity.c
@@ -2,19 +2,48 @@
 #include "game.h"
 #include "map.h"
 #include "cfg.h"
+#include <stddef.h>
+
+void
+_points(Entity *this, int ox, int oy, int *x0, int *x1, int *y0, int *y1)
+{
+	*x0 = this->pos[0] - this->width / 2 + ox;
+	*y0 = this->pos[1] - this->width / 2 + oy;
+	*x1 = *x0 + this->width - 1;
+	*y1 = *y0 + this->height - 1;
+}
+
 
 bool
 entity_collide(Entity *this, Game *g, int ox, int oy)
 {
 	(void)g;
-	const int x0 = this->pos[0] - this->width / 2 + ox;
-	const int y0 = this->pos[1] - this->height / 2 + oy;
-	const int x1 = x0 + this->width - 1;
-	const int y1 = y0 + this->height - 1;
+	int x0, y0, x1, y1;
+	_points(this, ox, oy, &x0, &x1, &y0, &y1);
 	return (map_get_px(x0, y0) == 1 || map_get_px(x0, y1) == 1 ||
 	        map_get_px(x1, y0) == 1 || map_get_px(x1, y1) == 1);
 }
 
+bool
+entity_meet(Entity *this, Entity *other)
+{
+	int tx0, ty0, tx1, ty1;
+	int ox0, oy0, ox1, oy1;
+	_points(this, 0, 0, &tx0, &tx1, &ty0, &ty1);
+	_points(other, 0, 0, &ox0, &ox1, &oy0, &oy1);
+	return (tx0 < ox1 && tx1 > ox0 && ty0 < oy1 && ty1 > oy0);
+}
+
+Entity *
+entity_place_meeting(Entity *this, Game *g, EntityType type)
+{
+	for (int i = 0; i < MAX_ENTITIES; i++)
+		if (this != &g->entities[i] && g->entities[i].type == type &&
+		    entity_meet(this, &g->entities[i]))
+			return &g->entities[i];
+	return NULL;
+}
+
 void
 entity_move(Entity *this, Game *g)
 {
diff --git a/src/entity.h b/src/entity.h
index be8fc0b..9460273 100644
--- a/src/entity.h
+++ b/src/entity.h
@@ -31,4 +31,6 @@ struct Entity {
 };
 
 bool entity_collide(Entity *this, struct Game *g, int ox, int oy);
+bool entity_meet(Entity *this, Entity *other);
+Entity *entity_place_meeting(Entity *this, struct Game *g, EntityType type);
 void entity_move(Entity *this, struct Game *g);