Xkeeper | Optimizing 75 @Xkeeper0 | Uploaded February 2008 | Updated October 2024, 9 hours ago.
Reading the comments and following the video will help this make sense. I'm sorry I couldn't add subtitles; the video doesn't play on my computer.

Anyway...

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Optimiznig Room #1~75 of Link's Awakening's Dungeons
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This room is a doozy.

Some quick explanations: The bar and numbers on the left indicate the current size of the room data, in bytes. Three bytes go to defining the room itself; the rest are all objects (or 5, if it has warp data).

In this editor, two-byte objects (i.e., one block) are outlined in green. Three-byte objects, that can be more than one block in size, are outlined in red. "Special" two-byte objects, like doors, are purple (or various shades thereof).

Outlines of objects flash when hovered over to make finding them easier; blocks can be either 2-bytes (1x1), or 3-bytes (*x1 or 1x*, not *x*).

After changing to the right room and getting a feel for the objects...

1: There's an object hiding under some floor tiles; it's an inwards top-right corner. We move this out of the way for now.

2: Next, we move the floor tiles out of the way. This is a 4x1 3-byte object.

3: As a demonstration, I put back the corner piece. It shows that this room may have looked differently to how it does now; a few rooms have objects like this that tell an entirely different story.

4: Enough with that piece; I go to pull out the right wall in the top right corner, and... it's still there! This one was hiding beneath the other wall piece for some reason. Let's move it to the top-left corner, out of the way.

5: Uh... There's a top-right corner piece hiding under it, too! This is especially odd, since the template this room uses has four corners already added... we'll move this off to the corner, too.

6: Let's pull the other wall piece out, too, just to make sure. There's nothing under it, so we'll put it back.

7: The inwards corner we found back at 1 gets shoved into the corner, since it's useless. We'll go ahead and move the floor tiles back, as well, and slide the hidden door object down to the bottom. (Door objects are always required; they help generate the game's automap.)

8: There's another floor tile here, too. That means there's a 2-byte "1x1" object, next to a 3-byte "4x1" object. We can remove the 2-byte object and make the 3-byte one longer and accomplish the same thing, so let's do that.

9: Cleaning up the objects we shoved into the corner. Already 8 bytes down, and we're nowhere near done yet...

10: If you're following the pointer closely, there's a 5x1 "deep water" object, partially covered by a 2x1 floor object. Odd, isn't it? (Perhaps this room was meant to be flippers-only at some point?) ... In any case, shrinking the water object and removing the floor would accomplish the same thing, but let's try something else!

11: So instead, we'll delete that object (and more, soon) and change the room BG to "E" (deep water). This works nicely, since most of the room is deep water compared to floor, meaning it'd be easier to have a few floor tiles, than to have many deep water ones... So now we have to add the floor tiles back and remove all the (now pointless) water ones.

12: We lengthen the floor tile object a bit to make up for the now-water floor. However, we're still one short (below it), so we need to insert another 2-byte floor object to cover that.

13: Removing the useless deep-water tiles. Their red outline disappears, and only the "floor" beneath them remains.

14: Oops. Forgot about the door. We'll go ahead and sweep that one under the floor tiles at the top, heh.

15: The shallow water tiles here aren't arranged optimaly. There are 5 three-byte objects; one for the two-block "tower", then one for every row of tiles beneath it. Instead, we'll use vertical rows, which means we can accomplish it in 3 three-byte objects, and one two-byte object for the bottom tile.

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Mission accomplished! We've managed to discover some interesting things in this room, and really squeeze it down by 28 bytes! This is *by far* the largest change I've made to these rooms so far, and it's also arguably the best.

If you have any questions on how things in this video worked, don't hesitate to ask.