changelayer
===========
Tags:
:dfhack-keybind:`changelayer`

:index:`Change the material of an entire geology layer.
<changelayer; Change the material of an entire geology layer.>` Note that one
layer can stretch across many z-levels, and changes to the geology layer will
affect all surrounding regions, not just your embark! Mineral veins and gem
clusters will not be affected. Use `changevein` if you want to modify those.

tl;dr: You will end up with changing large areas in one go, especially if you
use it in lower z levels. Use this command with care!

Usage::

   changelayer <material RAW id> [<options>]

When run without options, ``changelayer`` will:

- only affect the geology layer at the current cursor position
- only affect the biome that covers the current cursor position
- not allow changing stone to soil and vice versa

You can use the `probe` command on various tiles around your map to find valid
material RAW ids and to get an idea how layers and biomes are distributed.

Examples
--------

``changelayer GRANITE``
   Convert the layer at the cursor position into granite.
``changelayer SILTY_CLAY force``
   Convert teh layer at the cursor position into clay, even if it's stone.
``changelayer MARBLE all_biomes all_layers``
   Convert all layers of all biomes which are not soil into marble.

.. note::

    * If you use changelayer and nothing happens, try to pause/unpause the game
      for a while and move the cursor to another tile. Then try again. If that
      doesn't help, then try to temporarily change some other layer, undo your
      changes, and try again for the layer you want to change. Saving and
      reloading your map also sometimes helps.
    * You should be fine if you only change single layers without the use
      of 'force'. Still, it's advisable to save your game before messing with
      the map.
    * When you force changelayer to convert soil to stone, you might see some
      weird stuff (flashing tiles, tiles changed all over place etc). Try
      reverting the changes manually or even better use an older savegame. You
      did save your game, right?

Options
-------

``all_biomes``
   Change the corresponding geology layer for all biomes on your map. Be aware
   that the same geology layer can AND WILL be on different z-levels for
   different biomes.
``all_layers``
   Change all geology layers on your map (only for the selected biome unless
   ``all_biomes`` is also specified). Candy mountain, anyone? Will make your map
   quite boring, but tidy.
``force``
   Allow changing stone to soil and vice versa. **THIS CAN HAVE WEIRD EFFECTS,
   USE WITH CARE AND SAVE FIRST**. Note that soil will not be magically replaced
   with stone. You will, however, get a stone floor after digging, so it will
   allow the floor to be engraved. Similarly, stone will not be magically
   replaced with soil, but you will get a soil floor after digging, so it could
   be helpful for creating farm plots on maps with no soil.
``verbose``
   Output details about what is being changed.
