Edit Maps

The map compression is finally working and most of the maps look good now!
As a result it is now possible to edit a map and write it back to the ROM.
Some examples:

Map Exit Area

I discovered two more data bytes for the map exits that hold the size of the exit area.
The correct size of an exit area is now displayed on the maps:

As for map editing I will need some more extra effort since the compression routine doesn't work for all of the maps yet.

Edit Map Tiles

I finished the map compression routine so now it's possible to read back map arrangement and tileset data back to the ROM!
With this post I will show the editing of the tileset data:

You can choose a specific tile in the editor and change it's properties. You can change the X/Y mirror, the palette and tileset offset as well if the tile is displayed above the player or not.
You can also change the property of the tile which means what interaction takes place if the player is on a specific tile.
Here is a list of the possible properties:

0 - Tile Pass
1 - Steps
2 - Climb (Up/Down)
3 - Ramp (Down)
4 - ?
5 - Ramp (Left)
6 - Tile Block (Diagonal Left)
7- Climb (Left/Right)
8 - Jump Down
9 - Tile Block (Diagonal Right)
10 - Ramp (Right)
11 - ?
12 - Ramp (Up)
13 - ?
14 - ?
15 - Tile Block

As an example I changed the property of the wall tile from "Jump Down" to "Climb (Up/Down)".

The result in the game, the player doesn't jump down the wall but climbs it up and down:

I also changed the gras tile property so the player climbs from the left to the right:

In the next post I will show how you can edit a map and write it back to the ROM.

Map Display Improvement

I improved the display of the maps by considering the tileset offset bit which is part of the tileset data. This bit signals which part of a large tileset (Size = 0x4000 Bytes instead of 0x2000 Bytes) is to be used for a specific tile.
As a result, some maps look much better now, some of them can be seen in the following screenshots with a comparison of the old and new look.

Edward's Castle Old:

Edward's Castle New:

Inca Ship Old:

Inca Ship New:

Sprite Palettes

I found the palette offset information for the sprites so now the color palettes seem to be correct.
A few impressions:

 I also rewrited the loading algorithm for the sprites and it is much faster now. I needed this improvement for the display of the sprites on the maps which will be my next goal.
And as a little outlook:
I need to finish the map data compression routine to write the edited map data back to the ROM. Once this is done I will release the next version of the editor that will enable map editing and mabye even sprite editing.

Map Palettes

The map palettes are displayed correctly now! Worked faster than I expected :)

I played around a little with the map editor and added a second floor to the house:

I also renovated the dark part of Freejia a little:

Map Editor

It's now possible to edit the maps in the editor just as I did in the following screenshot:

I still need to finish the compression routine to make it possible to write the edited map data back to the ROM.
I'm also working on the map palettes currently. A map consists of several palettes (up to 8). The palette which a single map tile uses is assigned by a 3 bit index that is part of the tileset data.
With this index I willtry to display the map with all the right palettes.