Component: Hologram
==================
This component is provided by the [[block:hologram_projector|Hologram Projector]].  
These can be used to create holographic projections in a resolution of 48x32x48, over a maximum area of 9x6x9 blocks. Tier two holograms do not provide a higher resolution, instead they allow using up to three colors in the displayed hologram (as opposed to just one for the tier one hologram).

Component name: `hologram`.  
Callbacks:

- `clear()`  
  Clears the hologram.
- `get(x:number, y:number, z:number):number`  
  Returns the value at the specified position.
- `set(x:number, y:number, z:number, value:number or boolean)`  
  Set the value for the specified position.
- `fill(x:number, z:number[, minY:number], maxY:number, value:number)`  
  Fills an interval in the specified column column with the specified value. Will overwrite only the voxels in the interval. If `minY` is omitted it defaults to 1. The two interval ends are inclusive.  
  //Note:// Before 1.3.3 there was no `minY` argument and all voxels below and including the specified height would be set, all voxels above would be unset.
- `copy(x:number, z:number, sx:number, sz:number, tx:number, tz:number)`  
  Copies an area of columns by the specified translation.
- `getScale():number`  
  Returns the current render scale of the hologram.
- `setScale(value:number)`  
  Set the render scale. A larger scale consumes more energy. The minimum scale is 0.33, where the hologram will fit in a single block space, the maximum scale is 3, where the hologram will take up a 9x6x9 block space.
- `getTranslation:number, number, number`
  Return the current translation offset.
- `setTranslation(x:number, y:number, z:number)`
  Set the translation vector. The hologram display will be offset by this vector from its normal location. The maximum allowable translation is a function of tier. Units are the hologram's size, so the distance translated increases and decreases with scale as well.
- `maxDepth():number`  
  The color depth supported by the hologram.
- `getPaletteColor(index:number):number`  
  Get the hex color defined for the specified value.
- `setPaletteColor(index:number, value:number):number`  
  Set the hex color defined for the specified value.

Simple example program that allows setting individual voxels:
```lua
local component = require("component")
local hologram = component.hologram
local args = {...}
hologram.set(tonumber(args[1]), tonumber(args[2]), tonumber(args[3]), args[4] == "true" or args[4] == "on")
```

Example use (assuming it's saved as `holo-set.lua`):  
`# holo-set 16 8 20 true`

Further examples:

- [Holo Flow](https://github.com/OpenPrograms/Sangar-Programs/blob/master/holo-flow.lua)  
  This program generates a heightmap and 'moves' across it over time, creating the effect of a flowing terrain.
- [Holo Text](https://github.com/OpenPrograms/Sangar-Programs/blob/master/holo-text.lua)  
  This program generates a random heightmap and displays scrolling text above it.

Note, the second example is quite a bit more advanced then the first. **Important**: both scripts also need the [noise.lua](https://github.com/OpenPrograms/Sangar-Programs/blob/master/noise.lua) script to be in the same folder.

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