fix for [#36260] 2,300 Objects Makes Blender Unresponsive

- performance of outliner was low because of unoptimal data structures.
- now it uses BLI_mempool instead of custom mempool and GHash to make searches for duplicates faster.
- also fix undesired behaviour of BLI_mempool_as_arrayN

thanks to Campbell Barton and Lukas Tönne for helping me get a better fix put together.

1 files changed, 12 insertions, 2 deletions

diff --git a/source/blender/blenlib/intern/BLI_mempool.c b/source/blender/blenlib/intern/BLI_mempool.c
index 217a4b9d266..f370f32c31d 100644
--- a/source/blender/blenlib/intern/BLI_mempool.c
+++ b/source/blender/blenlib/intern/BLI_mempool.c
@@ -354,8 +354,18 @@ void BLI_mempool_as_array(BLI_mempool *pool, void **data)
  */
 void *BLI_mempool_as_arrayN(BLI_mempool *pool, const char *allocstr)
 {
-	void *data = MEM_mallocN((size_t)(BLI_mempool_count(pool) * pool->esize), allocstr);
-	BLI_mempool_as_array(pool, data);
+	char *data = MEM_mallocN((size_t)(pool->totused * pool->esize), allocstr);
+	BLI_assert(pool->flag & BLI_MEMPOOL_ALLOW_ITER);
+	if (data) {
+		BLI_mempool_iter iter;
+		char *elem, *p = data;
+		BLI_mempool_iternew(pool, &iter);
+		for (elem = BLI_mempool_iterstep(&iter); elem; elem = BLI_mempool_iterstep(&iter)) {
+			memcpy(p, elem, (size_t)pool->esize);
+			p += pool->esize;
+		}
+		BLI_assert((p - data) == pool->totused * pool->esize);
+	}
 	return data;
 }