xlib_playground

commit a20b34d8e11f276e4d2c206ad94a383e97881226
parent 3e95708f12e1d914a256d850d04d630b2b043fb5
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Tue, 10 Jan 2023 14:05:16 +0900

Implement collision handler.

Implemented collision handler which handles collision of nearest
pair first and distant ones last.
The code need refactoring.

Diffstat:
M
ex9/object.c
 | 
49
+++++++++++++++++++++++++++++++++++++++++++++++--

1 file changed, 47 insertions(+), 2 deletions(-)
diff --git a/ex9/object.c b/ex9/object.c
@@ -220,6 +220,30 @@ olqsortx(struct List *p)
 	lqsort(p, (int (*)(void *, void *))&olcmpx);
 }
 
+struct LLD {
+	struct Object *o0;
+	struct Object *o1;
+	float dist;
+};
+int
+lldcmpdst(struct LLD *p, struct LLD *q)
+{
+	if (p->dist < q->dist)
+		return -1;
+	else if (p->dist == q->dist)
+		return 0;
+	else
+		return 1;
+}
+void
+lldprint(struct LLD *p)
+{
+	printf("{");
+	oprint(p->o0);
+	printf(", ");
+	oprint(p->o1);
+	printf(", %2.0f}", p->dist);
+}
 /*
  * The order of list o will be changed.
  */
@@ -236,13 +260,34 @@ lhandle_collision(struct List *p)
 			((struct Object *)stack->item)->body.rectangle.w <=
 			((struct Object *)p->item)->p.x) {
 			// handle collision among the items in the stack.
+			// LLD: {struct Object *o0, struct Object *o1, float dist}
+			// sort LLD according to dist.
+			struct List *lld, *tmplld;
 			struct List *s, *t;
+			lld = NULL;
 			for (s = stack; s != NULL && s->next != NULL; s = s->next) {
 				for (t = s->next; t != NULL; t = t->next) {
-					ohandle_collision((struct Object *)s->item,
-						(struct Object *)t->item);
+					struct LLD *l;
+					l = (struct LLD *)malloc(sizeof(struct LLD));
+					l->o0 = (struct Object *)s->item;
+					l->o1 = (struct Object *)t->item;
+					l->dist = object_dist((struct Object *)s->item,
+							(struct Object *)t->item);
+					tmplld = laddfront(lld, l);
+					if (tmplld == NULL) {
+						fprintf(stderr, "lhandle_collision: Error. Could not"
+							"add item to lld\n");
+						exit(1);
+					}
+					lld = tmplld;
 				}
 			}
+			lqsort(lld, (int (*)(void *, void *))&lldcmpdst);
+			for (tmplld = lld; tmplld != NULL; tmplld = tmplld->next) {
+				ohandle_collision(((struct LLD *)tmplld->item)->o0,
+					((struct LLD *)tmplld->item)->o1);
+			}
+			lfree(lld);
 			lfree(stack);
 			stack = NULL;
 		}