Space Objects represent nearly everything you see in the night sky, they contain the information on how an object should behave and what it looks like.

The following are considered Space Objects:

• Planets
• Moons
• Stars
• Black Holes
• Nebulae
• Star Fields

Textured Object and Orbiting Object

A Textured Object is a subtype of Space Object that is visually represented with one or more textures.

The following are considered Textured Objects:

• Planets
• Moons
• Stars
• Black Holes
• Nebulae

Example of a Textured Object:

{
	"coords": { "right_ascension": {"hours": 5, "minutes": 34, "seconds": 31.94}, "declination": {"degrees": 22, "minutes": 0, "seconds": 52.2}, "distance": {"ly": 6500} },
	"axis_rotation": { "x_axis": 0, "y_axis": 0, "z_axis": 0 },
	"texture_layers":
	[
		{
			"texture": "stellarview:textures/environment/halo_template.png",
			"rgba": {"red": 255, "green": 0, "blue": 0, "alpha": 255},
			"blend": true,
			"size": 4488626469,
			"min_size": 0.9,
			"clamp_at_min_size": true,
			"rotation": 0,
			"uv": { "flip_uv": false }
		},
		{
			"texture": "stellarview:textures/environment/nebula/crab_nebula.png",
			"rgba": {"red": 255, "green": 255, "blue": 255, "alpha": 255},
			"blend": true,
			"size": 4488626469,
			"min_size": 0.5,
			"clamp_at_min_size": true,
			"rotation": 0,
			"uv": { "flip_uv": false }
		}
	]
}

The Textured Object has a special field called texture_layers which allows Resourcepacks to define the textures used to represent the object, layer by layer.
These Texture Layers are rendered from top to bottom, which means that in the above example, halo_template.png is rendered first and crab_nebula.png is rendered second, above the first one.

Texture Layer

A texture layer consists of the following fields:

• texture REQUIRED - Defines the path to the texture file used for rendering the layer.
• rgba REQUIRED - A set of 4 values, the first 3 (red, green, blue) define color adjustments and the last one (alpha) adjusts the transparency (255 = no transparency, 0 = full transparency).
• blend REQUIRED - Specifies whether or not the layer should blend with the background.
• size REQUIRED - Defines the visual size of the layer (in meters).
• min_size OPTIONAL - When specified, defines the minimal visual size of the object. When the object is far enough away that its visual size would be smaller than min_size, the layer stops rendering.
• clamp_at_min_size OPTIONAL - When specified and min_size is present, it changes the behaviour of min_size and instead of the layer no longer rendering, it will remain at this minimum size no matter how far away the object moves.
• rotation REQUIRED - Defines the amount by which the layer is rotated by along the axis facing the player (in degrees).
• uv OPTIONAL - Allows Resourcepacks to specify the phase_handler (OPTIONAL) which can change the UV coordinates of a texture based on time and flip_uv (OPTIONAL) decides whether the texture should have its U coordinate flipped.

"uv":
{
	"phase_handler":
	{
		"ticks_per_phase": 24000,
		"phase_tick_offset": 0,
		"columns": 4,
		"rows": 2
	},
	"flip_uv": true
}

In the above example taken from Luna, we define the 8 phases of the Moon using the following values:

• ticks_per_phase REQUIRED - Specifies how many ticks it takes before the phase switches to the next one. In this case, the Moon's phases change each day, so we set it to 24000 ticks, which is exactly 1 day in Minecraft.
• phase_tick_offset OPTIONAL - Specifies the offset at which the phases start. For example, setting it to 48000 would make the Moon start at its 3rd phase in this case.
• columns REQUIRED - defines the number of columns used for phases along the U-axis. In the case of the Moon, there are 4 (see Minecraft Wiki for reference)
• rows REQUIRED - defines the number of rows used for phases along the V-axis. In the case of the Moon, there are 2 (see Minecraft Wiki for reference)

Orbiting Object

An Orbiting Object is a subtype of Textured Object, which can orbit other Space Objects.

The following are considered Orbiting Objects:

• Planets
• Moons
• Stars
• Black Holes

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