While the default sets already cover a lot of different options, there are some things that could always be expanded.

For instance: what if you really want a matching interior for this neat tower?

The entrance area in the square part is no issue, but what about the octagonal part?

There you will need some edits, and today we will talk about how you can achieve them!

To make it easier to show what we need, I made an example room we will expand with the newly created tiles and that we will use as reference and base for the sketch.

This will help a lot by wrapping your head around which parts have to be modified in which way to match your new layout.

The turquoise line is the “new” shape of the room we are aiming for, an octagon. The red areas are roughly where the new walls will be placed.

Tip: If you have trouble getting a starting point, it helps to export your map and use that as background for your edits.

Before we actually adjust the shape of the wall tile, there is something else to keep in mind:

Our wall width as it is is 48 pixels, but the wall width for the diagonal wall is different, as of course, the diagonal through a square is longer than one of the sides.

What does that mean: if we “slope” our unedited wall tile, it might look a little weird, as if the bricks were extra wide. Its severity depends on the tile pattern we are starting with, but it is something to keep in mind.

How many pixels wide would be the diagonal wall, if we looked at it from the front?

48*48+48*48=ourresultinglength*ourresultinglength (A²+B²=C²)

Which gives us about 68 pixels as a result.

What does that mean?

Well, if you have a look at these two wall examples, A seems to be kind of overstretched, the arches and the rocks seem to be much wider than on the “fronts”. B looks much more natural, because it’s pattern has been edited to be closer to that before being made diagonal.

Look at the wall we are working with. It is built from bricks that are 24 pixels wide. So a tiling structure could be 24, 48, 72… and so on pixels wide.

72 is much closer to 68 than 48, so we edit our base pattern to have that width:

That is a simple copy and paste task.

Now we have a problem: Even though that is how that wall would look like, due to perspective this tile is still only one tile wide!

So, with copy and paste we make it more narrow and make sure we keep our pattern even and seamless.

Now we can just use “slope” (which is how this action is called in graphicsgale) in both directions and have neat diagonal walls that are seamless and don’t look off:

Tip: If you do a parallax map, you don’t have to ensure your tile is seamless and you can just transform the whole width to the accurate number you calculated. For different angles you will get different results. in general, you don’t have to be perfect, just watch out that perspective can change the length.

This already looks pretty neat. For an easy finish, you can now make the left side darker and the right lighter, as the light comes from the upper left corner:'

There you go, if we add the two new walls for example on an empty D sheet and import them, our basic map looks like this:

As you can see, only the top area is left, and you can see that I picked the “one tile wide ceiling autotile”-style for my map border here. If you use a different style, for example the ceiling tile for the whole area instead of blackness, you have to adapt that!

Unlike for the walls, for the ceiling “slope” is no option:

As you can see, the proportions look off and somehow too narrow.

Here, you need to turn the structure:

By turning the area by 45 degrees you make sure the proportions stay the same.

Now take that turned tile and edit it, so it tiles and you can map it seamlessly to any length you wish.

These results already look like they are working, but there is an issue left, as we will see when we test them on our map:

There isn't a good connection to the default tiles, and here our map on a layer behind the tiles can help a lot to get all the right shapes.

Because all we need to do, is to delete something from those diagonal walls that has the perfect shape:

At the blue spots the two ceiling parts have to have a junction. As they already have the same width, you just have to erase everything beyond the blue line:

Then merge the layers and clean the tile up to be ready to use:

Continue with all the junction areas:

As you can see, I already gave them the “black external void” for easier mapping later.

And then you have all the tiles you need to map a seamless wall around an octagonal room:

Now let’s have a look at some more special cases:

For those two ceilings, the diagonal structures work different:

The walls are quite easy, one is from our sample and the other one works the same way, but if we apply the ceiling, the trouble starts:

This looks off and there is no way to have a seamless texture here, and just cutting a diagonal part makes the junction look off.

A good solution would be to edit the stones to have them match each other:

Side note: for this specific ceiling I would also consider making the ceiling completely on the B/C/D sheet, as you see the sides have the same horizontal pattern the front has. For an overall better look I’d turn these parts by 90 degrees.

Maybe something like this:

For the other example, the problem is worse:

As you can see, the crenellations look off and seem to face a different direction than everything else.

For walls with crenellations or similar details, we will have to take a different approach. First we try to make the diagonal wall without the feature.

Here we usually have two options:

We can try to reconstruct the top from the gaps in the original wall OR we can look if we find something similar enough that we can edit into the diagonal part.

In this case, the outside version of these walls has such a structure we can borrow and edit into our diagonal part.

Now for the crenellations, I zoomed in a little so you can see better what has to be done there. The pinnacle top and bottom have to be treated separately, that’s why we cut them apart.

The top should be turned to a square here and then handled like the wall top, while the sides are handled like walls. Top is turned, sides are sloped and the brightness is adjusted.

Now we assemble it in a way that leads to a pleasing result (that is always a bit a case to case thing) and we are ready to go!

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