Scene Format

Dump

The ".dump" file stores a header containing width, height, SPP, render time; and the actual dump, which is three "doubles" per pixel. Doubles are double-precision floating-point format (sometimes called FP64 or float64).

Old Dump Format

GZIP stream of header + dump stored in column major order

New Dump Format

0x44 0x55 0x4D 0x50 <1 as int> <header> <dump compressed with fpc magic>

Header

<width int> <height int> <spp int> <render time in millis long>

Octree

The octree file is GZIP-compressed and contains a version integer, block palette, world octree, water octree, grass tinting, foliage tinting, and water tinting data. The first 4 bytes are a version number and currently must be between v3 and v6. v3-v4 octrees are currently converted to v5 for loading, as data nodes (only used for water and lava) were replaced by new per-variant types.

There are a few different octrees that are available within Chunky. These are NODE (legacy), PACKED (default), and BIGPACKED, all which have different pros and cons. Available octrees can be expanded via plugins such as aTom3333's Octree plugin.

There are a few different BVH build methods available within Chunky. Thses are SAH_MA (default), SAH, and MIDPOINT, all which have different pros and cons. Available BVHs can be expanded via plugins such as aTom3333's BVH plugin.

Octree Format

<version int> <block palette data> <world octree data> <water octree data> <grass tinting data> <foliage tinting data> <water tinting data if version >= 4>

The section of code

Block Palette Data

Stores NBT tags for each block.

<version int == 4> <number of block types> <Serialized NBT tags for each block in order>

World and water Octree Data

"octree is pretty complex lol"

"The octree itself is something like storing it depth first with 0xFFFF FFFF as a node and the type if it is a leaf."

World / Tint Textures

Stores tint colors for grass, foliage, and water as WorldTexture.

<number of tiles (chunks)> for each tile: <chunk x coordinate int> <chunk y coordinate int> <chunk texture in x major order, rgb as floats in linear color space>

Emittergrid

The ".emittergrid" is only generated if Emitter Sampling Strategy is set to ONE or All. Is also GZIP-compressed.

• Version 0 - <version as int> <grid size as int> <cell size as int> for each emitter position <positions as ints, -x, -y, -z corner, +0.5 to get center> for each grid <number of emitters in grid, index of emitters in positions array>

• Version 1 -<version as int> <cell size as int> <grid offset x> <grid size x> <grid offset y> ...

• Version 2 - <x,y,z center float, radius as float> for emitter position

Scene Description Format (SDF)

Most of the settings in Chunky scenes are stored in Scene Description files using a JSON-based file format. This page documents the SDF file format. The documentation is currently incomplete, and may lag behind the current Chunky version as new versions are released. Check the version history at the end of this page to see the latest updates made to the SDF documentation.

SDF JSON files are stored in the scene directory and the filename is based on the scene name with .json appended. For example, the JSON file for a scene named "MyScene" would be "MyScene.json".

Structure

General

Key	Value range	Default value	Description
sdfVersion	Integer	9	Scene Description Format (SDF) version
name	String		Scene name
width	Integer	400	Canvas width
height	Integer	400	Canvas height
yClipMin	Integer		Clipping world when loading into scene
yClipMax	Integer		Clipping world when loading into scene
yMin	Integer		Slicing map view (impacts octree offset)
yMax	Integer		Slicing map view (impacts octree offset)
exposure	Number	1	Camera exposure
postprocess	{"NONE", “TONEMAP2”, "GAMMA", "TONEMAP3", "TONEMAP1"}	“GAMMA”	Tonemapping operator
outputMode	{"PNG", "TIFF_32", “PFM”}	“PNG”	Image output mode
renderTime	Number		Current cumulative rendering time
spp	Integer		Current samples per pixel (SPP)
sppTarget	Integer	1000	Render SPP target
rayDepth	Integer	5	Ray recursion depth
pathTrace	Boolean	false	Rendering mode (true = path tracing, false = preview)
dumpFrequency	Integer	500	How often the current render state is saved (samples per state save)
saveSnapshots	Boolean	false	Whether a snapshot image is saved for each render dump
emittersEnabled	Boolean	false	Whether emitters should emit light or not
emitterIntensity	Number	13.0	Controls intensity of emitters
sunEnabled	Boolean	true	Whether the sun should emit light or not
stillWater	Boolean	false	Whether water should be still or wavy
waterOpacity	Number {0 to 1}	0.42	Opacity of water
waterVisibility	Number	9.0	Distance rays can travel in water in blocks
useCustomWaterColor	Boolean	false	Toggle between biome tinted water and custom water color
waterColor	RGB Object		See below
fogColor	RGB Object		See below
fastFog	Boolean	true	Faster fog algorithm
biomeColorsEnabled	Boolean	true	Enable biome tint
transparentSky	Boolean	false	Treat sky as transparent
fogDensity	Number	0.0	Fog density
skyFogDensity	Number {0 to 1}	1.0	Controls the amount fog blends into the sky
waterWorldEnabled	Boolean	false	Enable water world
waterWorldHeight	Number	63.0	Controls height of water world
waterWorldHeightOffsetEnabled	Boolean	true	Applies Minecraft water offset
waterWorldClipEnabled	Boolean	true
renderActors	Boolean	true
world	World Object		See below
camera	Camera Object		See below
sun	Sun Object		See below
sky	Sky Object		See below
cameraPresets	Array of Camera Preset Objects		See below
materials	Material Array Object		See below
chunkList	Array of integer arrays		Chunks in the scene
entities	Array of Entity Objects		Static entities in the scene, e.g. paintings
actors	Array of Actor Objects		Posable entities such as players.
entityLoadingPreferences	entityLoadingPreferences Object		See below
octreeImplementation	{“PACKED”, “NODE”, “BIGPACKED”}	“PACKED”	Octree implementation to use
bvhImplementation	{“SAH_MA”, “SAH”, “MIDPOINT”}	“SAH_MA”	BVH implementation to use
emitterSamplingStrategy	{“NONE”, “ONE”, “ALL”}	“NONE”	Enables NEE for emitters for one or all per bounce
preventNormalEmitterWithSampling	Boolean	true	Attempts to prevent normal emitters and just use NEE
animationTime	Number	0.0
renderer	{“PathTracingRenderer”}	“PathTracingRenderer”	Change renderer used for path tracing
previewRenderer	{“PreviewRenderer”}	“PreviewRenderer”	Change renderer used for previews
additionalData	{}	{}	Unknown

RGB Object

Key	Value range
red	Number {0 to 1}
green	Number {0 to 1}
blue	Number {0 to 1}

World Object

Key	Value range
path	String
dimension	Integer {0 to 2}

Camera Object

Key	Value range	Default value	Description
name	String	“camera 1”
position	XYZ Object		See [below](#xyz-objec
orientation	Direction Object		See below
projectionMode	{"PINHOLE", "PARALLEL", "FISHEYE", "STEREOGRAPHIC", "PANORAMIC", "PANORAMIC_SLOT", “ODS_LEFT”, “ODS_RIGHT”}	“PINHOLE”	Camera projection mode
fov	Number	70.0	Field of View
dof	Number	"Infinity"	Depth of Field, also accepts numbers like "0.0"
focalOffset	Number	2.0	Distance to target
shift	XY Object		See XYZ object

XYZ Object

Note - XY Object is a XYZ Object just without the Z component.

Key	Value range
x	Number
y	Number
z	Number

Direction Object

Key	Value range	Description
roll	Number	In radians
pitch	Number	In radians
yaw	Number	In radians

Sun Object

Key	Value range	Default value	Description
altitude	Number {0 to PI/2}	1.0471975511965976	The direction to the sun above the horizon (60 degrees in radians)
azimuth	Number {0 to 2PI}	1.2566370614359172	The direction to the sun measured from north (-72 degrees in radians)
intensity	Number	1.25	Sunlight scaling factor
color	RGB Object		See above
drawTexture	boolean	true	Whether to draw the resource pack texture for the sun or not

Sky Object

Key	Value range	Default value	Description
skyYaw	Number {0 to 2PI}	0.0	Offset angle for the sky map in radians
skyMirrored	Boolean	true	Enables mirroring of the skymap at the horizon (use when the vertical skymap angle is 90 degrees)
skyLight	Number	1.0	Sky light scaling factor
mode	{"SIMULATED", "SOLID_COLOR", “GRADIENT”, “SKYMAP_PANORAMIC”, “SKYMAP_SPHERICAL”, “SKYBOX”, “BLACK”}	"SIMULATED"	Sky rendering mode
horizonOffset	Number	0.0	Offset the horizon to simulate a curved earth. This helps hiding the horizon below distant objects.
cloudsEnabled	Boolean	false	Enable clouds
cloudSize	Number	64.0	Scale cloud map
cloudOffset	XYZ Object		See above
gradient	Array of Gradient Objects		See below
color	“RGB” Object		Not really an RGB object.. but kinda?
simulatedSky	{"Preetham", “Nishita”}	"Preetham"	Select method of rendering a simulated sky
skyCacheResolution	Integer	128	Internal resolution to be used for simulated sky, is interpolated
skymap	String		Path to skymap
skybox	Array of six Strings		Array of six paths to skybox images

Gradient Object

Key	Value range
rgb	String (RGB HEX)
pos	Number

Camera Preset Object

Key	Value range	Default value	Description
"camera object: name"	Camera Object		"camera name" is the value of the name field

Material Array Object

Key	Value range	Default value	Description
"block / entity name"	Material Object		Ie "minecraft:acacia_log": {...}

Material Object

Key	Value range	Default value	Description
emittance	Number {0+}		How much light the material emits
specular	Number {0 to 1}		Specular reflection coefficient
roughness	Number {0 to 1}		Blurriness of reflection
ior	Number		Index of refraction
metalness	Number {0 to 1}		Percentage of rays tinted by material color (complex fresnel)

Entity Object

Key	Value range	Default value	Description
kind	String		Minecraft entity name
position	XYZ Object		See above
rotation	Integer		Entity rotation
design	Banner Design Object		See below
text	Array of four Text Objects		See below
direction	Integer		Entity rotation
material	{“oak”, "dark_oak"} TODO		Sign Material
art	String		Minecraft art ID
angle	Number		art angle? Legit just at n90 degrees.
placement	Integer		Head placement?
skin	String		Head texture URL

Banner Design Object

Key	Value range	Default value	Description
base	Integer		Banner base
patterns	Arrange of Patterns Object		See below

Patterns Object

Key	Value range	Default value	Description
pattern	{"b", "bs", "ts", "ls", "rs", "cs", "ms", "drs", "dls", "ss", "cr", "sc", "ld", "rud", "lud", "rd", "vh", "vhr", "hh", "hhb", "bl", "br", "tl", "tr", "bt", "tt", "bts", "tts", "mc", "mr", "bo", "cbo", "bri", "gra", "gru", "cre", "sku", "flo", "moj", "glb", "pig"}		Banner pattern code
color	Integer

Text Object

Key	Value range
text	String
color	Integer

Actor Object

Key	Value range	Default value	Description
kind	String		Minecraft posable name
position	XYZ Object		See above
scale	Number		Scale actor
headScale	Number		Scale actor head
showArms	Boolean		Hide / show actor arms
gear	Array of Gear Objects		See below
pose	Pose Object		See below
invisible	Boolean		If actor is invisible
noBasePlate	Boolean		If armour_stand base plate is visible

Gear Object

Key	Value range	Default value	Description
head	ID_Skin Object		“head”
OR
{“feet”, “legs”, “chest”}	“id”: “...”		Minecraft item ID

ID_Skin Object

Key	Value range	Default value	Description
id	String	“minecraft:player_head”
skin	String		URL for skin texture

Pose Object

Key	Value range	Default value	Description
all	Array of three Numbers		Array of parts Roll, Pitch, and Yaw
head	Array of three Numbers		Array of parts Roll, Pitch, and Yaw
chest	Array of three Numbers		Array of parts Roll, Pitch, and Yaw
leftArm	Array of three Numbers		Array of parts Roll, Pitch, and Yaw
rightArm	Array of three Numbers		Array of parts Roll, Pitch, and Yaw
leftLeg	Array of three Numbers		Array of parts Roll, Pitch, and Yaw
rightLeg	Array of three Numbers		Array of parts Roll, Pitch, and Yaw

entityLoadingPreferences Object

Key	Value range	Default value	Description
se.llbit.chunky.entity.Book		true	Whether to load book entities
se.llbit.chunky.entity.ArmorStand		true	Whether to load armor stand entities
se.llbit.chunky.entity.PaintingEntity		true	Whether to load painting entities
se.llbit.chunky.entity.PlayerEntity		true	Whether to load player entities
other		true	Whether to load “other” entities

Scripting

A simple way to process scene files is by using a scripting language such as Python. For example, below is a Python script that generates individual scenes for each chunk in a square grid of chunks. The script uses an original scene as template for the new scenes.

import json
import os.path
original_scene = 'D:\Users\Jesper\.chunky\scenes\shore-sun.json'
scene_dir = os.path.abspath(os.path.join(original_scene, os.pardir))
with open(original_scene, 'r') as f:
    scene = json.load(f)
for x in range(-10, 1):
    for z in range(110, 119):
        scene_name = 'chunk_%dx_%dz' % (x, z)
        scene['name'] = scene_name
        scene['chunkList'] = [ [ x, z ] ]
        scene['spp'] = 0
        scene['renderTime'] = 0
        new_scene = os.path.join(scene_dir, scene_name + '.json')
        print('Writing scene file %s' % new_scene)
        with open(new_scene, 'w') as f:
            json.dump(scene, f)

Version History

• Version 2 (Chunky 1.2.0 to 1.2.3)
• Version 3 (Chunky 1.3-alpha1 to 1.3.3)
• Version 4 (Chunky 1.3.4)
  • removed clearWater (Boolean)
  • added waterOpacity (Number)
  • added waterVisibility (Number)
  • added waterColor (RGB Object)
  • added useCustomWaterColor (Boolean)
• Version 5 (Chunky 1.3.5-alpha5)
  • removed atmosphereEnabled (Boolean)
  • removed volumetricFogEnabled (Boolean)
  • added fogDensity (Number)
  • added fogColor (RGB Object)
  • added fastFog (Boolean)
• Version 6 (Chunky 1.3.5-alpha5)
  • Changed postprocess from Integer to Enum
  • Added outputMode (Enum)
• Version 7 (Chunky 1.3.8)
  • Added renderActors (Boolean)
  • Added actors (Array of Entity Objects)
• Version 8 (Chunky 1.4.3)
  • Added materials (material properties)
• Version 9 (Chunky 1.4.4)
  • Changed entity pose format.
  • Added entity armor items.