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# TextureResource.Compression.ASTCBlockSize

The compressed block size.

```
enum ASTCBlockSize
```

## Overview> Note: RealityKit stores block pixel data in groups of 128 bits.
> For instance, a `block4x4` bits per pixel is
> 128/(4*4) = 8 bit per pixel.

## Topics

### Compression block sizes

[`case block4x4`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block4x4)

[`case block5x4`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block5x4)

[`case block5x5`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block5x5)

[`case block6x5`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block6x5)

[`case block6x6`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block6x6)

[`case block8x5`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block8x5)

[`case block8x6`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block8x6)

[`case block8x8`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block8x8)

[`case block10x10`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block10x10)

[`case block10x5`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block10x5)

[`case block10x6`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block10x6)

[`case block10x8`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block10x8)

[`case block12x10`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block12x10)

[`case block12x12`](/documentation/RealityKit/TextureResource/Compression/ASTCBlockSize/block12x12)

### Comparing compression block sizes

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Equatable`](/documentation/Swift/Equatable)

[`Encodable`](/documentation/Swift/Encodable)

[`Decodable`](/documentation/Swift/Decodable)

[`Hashable`](/documentation/Swift/Hashable)

---

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