Flattening is a concept that came from Apophysis when 3D capability was added to the algorithm. With that addition, some new variations altered the Z coordinate while others did not. Using Z can have desirable effects if that’s what the artist intended, however it can also have undesirable effects. Artists needed a way to disable all Z coordinate modification during iteration and were given the Flatten variation to do that.

When the Flatten variation is added to an xform, it will ensure the Z coordinate of the returned point is zero when that xform is applied. To accomplish this, it’s automatically placed at the end of the variation list for the xform. This is the only variation where the order is automatically changed, an one of the few where order matters.

Fractorium allows for flatting via the Tools | Flatten menu item. This will add the flatten variation to every xform which does not contain the following variations:

pre_crop
pre_falloff2
pre_rotate_x
pre_rotate_y
pre_ztranslate
blur3D
bubble
bwraps
bwraps2
crop
cylinder
falloff2
hemisphere
julia3D
julia3Dz
linear3D
zblur
zcone
ztranslate
post_crop
post_falloff2
post_rotate_x
post_rotate_y
curl3D_cz

This list was gotten from Apophysis to maintain compatibility. If the automatic flattening does not provide what you need, you can always manually add/remove it to/from any xform you wish.

You can remove the Flatten variation from all xforms by clicking the Tools | Unflatten menu item. Both Flatten and Unflatten observe the Apply All checkbox on the Flame tab, which will apply the operation to all flames in the current file.

If you are using parameters from Apophysis and are finding that the output images look different, try applying flattening to the flame and it will likely produce the same results you are looking for. Note that Fractorium makes an educated guess about where the original flame parameters came from by inspecting the version tag in the Xml. It automatically applies flattening when loading a flame from any program other than Fractorium.