Struct TextureCompressor 

pub struct TextureCompressor { /* private fields */ }

GPU-accelerated texture compressor for BC1 and BC4 block formats.

Create once with TextureCompressor::new, then call TextureCompressor::compress for each image. The width and height supplied at construction time are fixed for the lifetime of this object.

When no wgpu backend is available (e.g., headless CI) compress falls back automatically to the CPU path provided by compress_bc1_block_cpu and compress_bc4_block_cpu.

Implementations

impl TextureCompressor

pub fn new( ctx: &GpuContext, format: TextureFormat, width: u32, height: u32, ) -> GpuResult<Self>

Create a new TextureCompressor.

Arguments

• ctx — Active GPU context.
• format — Target compressed format (Bc1RgbUnorm or Bc4RUnorm).
• width — Pixel width of images to compress (must be a multiple of 4).
• height — Pixel height of images to compress (must be a multiple of 4).

Errors

Returns GpuError::InvalidKernelParams when either dimension is not a multiple of 4, or a pipeline error when WGSL compilation fails.

pub fn format(&self) -> TextureFormat

The target texture format.

pub fn width(&self) -> u32

Image width (pixels) supplied at construction time.

pub fn height(&self) -> u32

Image height (pixels) supplied at construction time.

pub fn compress(&self, ctx: &GpuContext, input: &[u8]) -> GpuResult<Vec<u8>>

Compress input using this compressor’s format.

• BC1: input must be width × height × 4 bytes (RGBA8 row-major).
• BC4: input must be width × height bytes (R8 row-major).

Returns (width/4) × (height/4) × 8 bytes of block-compressed data.

GPU path

When a wgpu backend is available the method dispatches a compute shader and reads back the result synchronously.

CPU fallback

When self.pipeline is None (shader compilation failed or no backend) or when wgpu dispatch fails, the method falls back to the pure-Rust block encoders compress_bc1_block_cpu / compress_bc4_block_cpu.

Errors

Returns an error when the input length does not match the expected size for the configured format and dimensions.