edds

Minimal EDDS reader/writer for Arma/DayZ with LZ4 chunk-stream support.

edds reads and writes EDDS files (DDS header + block table + block bodies), supports COPY/LZ4 blocks, and decodes the largest mipmap into RGBA.

Implemented

• EDDS read (config + decode largest mip)
• EDDS write (RGBA/BGRA and BC1/BC2/BC3, optional mipmaps)
• Stream-oriented encode/decode APIs for io.Reader / io.Writer
• Reusable Encoder / Decoder for batch pipelines
• Optional passthrough of bcn.EncodeOptions (quality/workers/etc.)
• LZ4 Enfusion chunk-stream compress/decompress (COPY/LZ4 blocks)
• DDS header interop via github.com/woozymasta/bcn

Usage

Read EDDS

img, err := edds.Read("atlas.edds")
if err != nil {
  /* handle */
}
_ = img

Read config only

cfg, err := edds.ReadConfig("atlas.edds")
if err != nil {
  /* handle */
}
_ = cfg

Write EDDS with mipmaps (BGRA8)

err := edds.WriteWithMipmaps(img, "atlas.edds", 0) // 0 = full chain
if err != nil {
  /* handle */
}

Write EDDS with format

err := edds.WriteWithFormat(img, "atlas_bc5.edds", bcn.FormatBC5, 0)
if err != nil {
  /* handle */
}

Write EDDS with full options

err := edds.WriteWithOptions(img, "atlas_dxt5.edds", &edds.WriteOptions{
  Format:     bcn.FormatDXT5,
  MaxMipMaps: 0,
  Compression: edds.CompressionOptions{
    Mode: edds.CompressionLZ4,
  },
  EncodeOptions: &bcn.EncodeOptions{
    QualityLevel: 8,
    Workers: 0,
  },
})
if err != nil {
  /* handle */
}

Use CompressionNone for COPY blocks or CompressionLZ4HC with HCLevel for slower size-priority compression.

Write EDDS from pre-encoded blocks

err := edds.WriteFromBlocks("atlas_bc3.edds", bcn.FormatDXT5, width, height, mipPayloads)
if err != nil {
  /* handle */
}

Stream encode/decode

var buf bytes.Buffer

if err := edds.Encode(&buf, img); err != nil {
  /* handle */
}

decoded, err := edds.Decode(bytes.NewReader(buf.Bytes()))
if err != nil {
  /* handle */
}
_ = decoded

Pre-encoded mip payloads can be written to any io.Writer:

err := edds.EncodeFromBlocks(&buf, bcn.FormatDXT5, width, height, mipPayloads)
if err != nil {
  /* handle */
}

Batch encode/decode

Use one Encoder or Decoder per worker goroutine to reuse internal buffers:

enc := edds.NewEncoder()
dec := edds.NewDecoder()

_ = enc.Encode(w, img)
decoded, err := dec.Decode(r)
_ = decoded
_ = err

Encoder and Decoder are not safe for concurrent use. Images returned by Decoder share its reusable pixel buffer and remain valid only until the next decode call on the same decoder. Copy the image if it must be retained.

Notes

• Package-level encode/decode supports BGRA8, RGBA8, DXT1/3/5, BC4, BC5.
• DXT3, BC4, BC5 may decode in tooling but may not display correctly in-game/Workbench.
• Only 2D textures are handled.