vengi/docs/voxconvert/Index.md

# General

Convert voxel volume formats between each other or export to obj or ply.

* [Supported voxel formats](../Formats.md)
* [Scripting support](../LUAScript.md)

## Usage

`./vengi-voxconvert --merge --scale --input infile --output outfile`

* `--export-palette`: will save the included palette as png next to the source file. Use in combination with `--src-palette`.
* `--filter <filter>`: will filter out layers not mentioned in the expression. E.g. `1-2,4` will handle layer 1, 2 and 4. It is the same as `1,2,4`. The first layer is `0`. See the layers note below.
* `--force`: overwrite existing files
* `--input <file>`: allows to specify input files. You can specify more than one file
* `--merge`: will merge a multi layer volume (like vox, qb or qbt) into a single volume of the target file
* `--mirror <x|y|z>`: allows you to mirror the volumes at x, y and z axis
* `--output <file>`: allows you to specify the output filename
* `--pivot <x:y:z>`: change the pivots of the volume layers. Not all voxel formats support this.
* `--rotate <x|y|z>`: allows you to rotate the volumes by 90 degree at x, y and z axis
* `--scale`: perform lod conversion of the input volume (50% scale per call)
* `--script "<script> <args>"`: execute the given script - see [scripting support](../LUAScript.md) for more details
* `--src-palette`: will use the included palette and doesn't perform any quantization to the default palette
* `--translate <x:y:z>`: translates the volumes by x (right), y (up), z (back)

Just type `vengi-voxconvert` to get a full list of commands and options.

Using a different target palette is also possible by setting the `palette` config var.

`./vengi-voxconvert -set palette /path/to/palette.png --input infile outfile`

The palette file has to be in the dimensions 1x256. It is also possible to just provide the basename of the palette.
This is e.g. `nippon`. The tool will then try to look up the file `palette-nippon.png` in the file search paths.

You can convert to a different palette with this command. The closest possible color will be chosen for each
color from the source file palette to the specified palette.

### The order of execution is:

* filter
* merge
* scale
* mirror
* rotate
* translate
* script
* pivot

### Layers

Some formats also have layer support. Our layers are maybe not the layers you know from your favorite editor. Each layer can currently only have one object or volume in it. To get the proper layer ids (starting from 0) for your voxel file, you should load it once in [voxedit](../voxedit/Index.md) and check the layer panel.

Especially magicavoxel supports more objects in one layer. This might be confusing to get the right numbers for `voxconvert`. See [this issue](https://github.com/mgerhardy/engine/issues/68) for a few more details.

## Level of detail (LOD)

Generate a lod scaled by 50% from the input model.

`./vengi-voxconvert -s --input infile.vox output.vox`

## Merge several models

Merge several models into one:

`./vengi-voxconvert --input one.vox --input two.vox --output onetwo.vox`

## Generate from heightmap

Just specify the heightmap as input file like this:

`./vengi-voxconvert --input heightmap.png --output outfile.vox`

## Translate the voxels

You can translate the voxels in the world like this:

`./vengi-voxconvert --translate 0:10:0 --input heightmap.png --output outfile.vox`

This would move the voxels 10 units upwards. But keep in mind that not every format supports
to store a translation offset.

## Execute lua script

Use the `--script` parameter:

`./vengi-voxconvert --script "cover 2" --input infile.vox --output outfile.vox`

This is executing the script in `./scripts/cover.lua` with a parameter of `2`.

`./vengi-voxconvert --script "./scripts/cover.lua 2" --input infile.vox --output outfile.vox`

This is doing exactly the same as above - just with a full path.

See the [scripting](../LUAScript.md) documentation for further details.

## Extract palette png

Saves the png in the same dir as the vox file:

`./vengi-voxconvert --src-palette --export-palette --input infile.vox --output outfile.vox`

There will be an `infile.png` now.

## Extract single layers

Extract just a few layers from the input file.

`./vengi-voxconvert --filter 1-2,4 --input infile.vox --output outfile.vox`

This will export layers 1, 2 and 4.

## Convert to mesh

You can export your volume model into a obj or ply.

`./vengi-voxconvert --input infile.vox --output outfile.obj`

Config vars to control the meshing:

* `voxformat_ambientocclusion`: Don't export extra quads for ambient occlusion voxels
* `voxformat_mergequads`: Merge similar quads to optimize the mesh
* `voxformat_reusevertices`: Reuse vertices or always create new ones
* `voxformat_scale`: Scale the vertices by the given factor
* `voxformat_quads`: Export to quads
* `voxformat_withcolor`: Export vertex colors
* `voxformat_withtexcoords`: Export texture coordinates

See `./vengi-voxconvert --help` or [configuration](../Configuration.md) for more details.

## Batch convert

To convert a complete directory of e.g. `*.vox` to `*.obj` files, you can use e.g. the bash like this:

```bash
for i in *.vox; do vengi-voxconvert --input $i --output ${i%.vox}.obj; done
```

An example for the windows powershell to extract single layers into a new model

```ps
$array = "1-2,5", "1-2,7"
foreach ($i in $array){
  ./vengi-voxconvert --filter $i --input input.vox --output output_$i.vxm
}
```

## Screenshots

![image](https://raw.githubusercontent.com/wiki/mgerhardy/engine/images/voxconvert-export-to-obj.png)

![image](https://raw.githubusercontent.com/wiki/mgerhardy/engine/images/voxconvert-export-obj.png)