Some of BR's features are for power users, or aren't very discoverable in the UI. This list attempts to make these neat, but less commonly used features more visible.
BR's Duplicate Room feature lets you create exact copies of existing rooms without much effort. However, it's also possible to create an exact mirrored duplicate! This is a pretty common technique for quickly padding out room counts when creating a lot of them, so BR attempts to make this a bit easier. Simply hold Alt and Duplicate will become Mirror (creates a horizontally mirrored duplicate) or Alt+Shift and it will become Mirror Y. (creates a vertically mirrored duplicate) This accounts for directional entities like Grimaces, Wall Huggers, etc. and mirrors them as needed. You can support this for your own entities via the MirrorX and MirrorY attributes. See BR's Entities xml for examples.
To play as a tainted character, in the Test Configuration Dialog enter the character's name either as 'Tainted XXX' or 'XXX-b'. Incidentally, to play as forgotten, use 'the_forgotten' as the name.
Sometimes it's desirable to replace a few entities in a room with another one. Simply select these entities and then Alt+Click the replacement entity in the palette and you're done!
Sometimes you'd like to keep an entity filter active while selecting new entities to paint for the current room. Ctrl+Click the entity you'd like to paint and the current entity filter will not change. You can also invert the normal behavior by toggling Edit > Pin Entity Filter.
Sometimes it's desirable to place a pre-configured entity multiple times. This can be done via copy-paste, or more conveniently by selecting an in-room entity that matches the palette while painting. The painted entity will have the same attributes as the selected one.
If you'd like to filter rooms by things other than entities, type, and size, you can filter for other room properties through the Other filter. This includes properties like weight, difficulty, subtype, and the last time the room was tested.
- As an aside, last test time is filtered differently from other properties.
- If no range is used, rooms that have never been tested or were tested before the left time are included.
- If a range is used, only rooms tested between the times are included, starting with the right time and ending with the left.
While already detailed in the FAQ, this feature lets you run scripts as needed when BR performs various actions. Save hooks run scripts on newly saved stbs, Test hooks run on output xmls before the game launches, etc.
Occasionally you may decide to move certain rooms to another file, or want copies there. It would be painstaking to copy them by hand, so BR provides an Copy to File option which lets you select a room file to copy selected rooms to.
Did you know that when bulk replacing entities, the "replaced" entity is based on your currently selected entity in the room, and the "replacement" entity is based on your currently selected entity in the palette? This can save some time when performing this process as you don't have to remember the actual ids. Additionally, leaving the variants and/or subtypes as -1 will either match any, for the replaced entity, or preserve the original value, for the replacement.
In the event of replacing entities across many files, check out the bulk-entity-replacer script in src. Given a config file specifying replaced entities and files to operate on, this will replace entities across those files.
Some entities (e.g. Ball & Chain and Fissure Spawner) use their SubType to customize their behavior, rather than using it as another variant (e.g. pickups). Middle-click entities to access these customizable properties.
Ever have a room file where the organization has completely gotten away from you and everything is completely out of order? This fixes that by changing their variants to be in sequence by type, starting with the first one it sees. You can also sort the rooms by variant or name before doing this.
Hypothetically you've created a bunch of rooms with... nothing in them. You did this as part of a placeholder comedic naming scheme involving a certain rapping community member, perhaps. Well now you need to figure out which ones still need attention, but fear not. If you filter for the "Null" room type, since the type isn't used much normally the filter will also include "empty" rooms. The rooms can contain a few harmless entities, like decorations and cobwebs. You can add your own entities with the 'InEmptyRooms' tag. You can also use this to filter for rooms without combat by toggling Edit > Non-Combat Room Filter.
Sometimes you want BR to open as fast as possible and don't care about mods. For that, set DisableMods to 1 in your settings.ini file in the BR folder.
If you're running BR with a console window open, you may notice some warnings from libpng complaining about formats. This is because of issues with how your custom entities icons are saved. To fix these issues and silence the warning, set FixIconFormat to 1 in the settings.ini. It will turn itself off after BR loads mods once, since it shouldn't have any additional work to do.
There is some subset of users who are using DRM free copies of Isaac, or test builds not through Steam. The test launcher uses Steam directly to avoid an annoying popup, but if the Isaac exe is DRM free launching through Steam is unintended behavior and undesired. To disable trying to launch Isaac through steam, set ForceExeLaunch to 1 in your settings.ini.
There is some subset of users who have found that the normal test launch method for InstaPreview is rejected by their OS. To get around this, set ForceUrlLaunch to 1 in your settings.ini.
Anitbirth is capable of Instapreview testing for goofing around. In the absence of a true compatibility mode, you can quickly test rooms for poking its behavior. To test rooms in Anti, go to settings.ini and set AntibirthPath to the folder you have Antibirth installed in (formatted like InstallPath) and set CompatibilityMode to Antibirth. This only supports Instapreview. For Antibirth enemies, check out resources/EntitiesAntibirth.xml. Icon PRs welcome!