vtf

0 dependency parser for Valves own .vtf (Valve Texture Format) Source Engine textures.

go get github.com/galaco/vtf/v2

Features

• Supports versions 7.0-7.5
• Full header data
• Low resolution thumbnail loading
• Complete mipmap + high-resolution texture loading, including animated frames, cubemaps and volume textures
• v7.3+ resources (key values, sprite sheets, CRCs etc.)
• Streaming reads: only the bytes the texture occupies are read, and sizes claimed by a header are never trusted for allocation
• Optional conversion to image.Image, with the vtfimage package

Usage

package main

import (
	"log"

	"github.com/galaco/vtf/v2"
)

func main() {
	texture, err := vtf.ReadFromFile("foo.vtf")
	if err != nil {
		log.Fatal(err)
	}

	header := texture.Header()
	log.Println(header.Width, header.Height, header.HighResImageFormat)

	// Raw data of the largest mipmap of the first frame, face and slice
	data := texture.Image()

	log.Println(len(data), "bytes")

	// Any mipmap (0 is the largest), frame, cubemap face or volume slice
	smallest := texture.MipmapCount() - 1
	mipmap, err := texture.Mipmap(smallest, 0, 0, 0)
	if err != nil {
		log.Fatal(err)
	}
	width, height, depth := texture.MipmapDimensions(smallest)
	log.Println(width, height, depth, len(mipmap))
}

Image data is returned in its stored format (Header().HighResImageFormat), and shares memory with the texture.

To read only the header:

reader := vtf.NewReader(file)
header, err := reader.ReadHeader()
// Optionally, continue reading the rest of the texture
texture, err := reader.Read()

v7.3+ resources:

if kv, ok := texture.Resource(vtf.ResourceTagKeyValues); ok {
	log.Println(string(kv.Data))
}

Converting to image.Image

The vtfimage package converts image data to an image.Image, and registers the format with the image package:

import (
	"image"
	"image/png"

	_ "github.com/galaco/vtf/v2/vtfimage"
)

img, _, err := image.Decode(file)
err = png.Encode(out, img)

Or convert a specific mipmap, or the thumbnail, with vtfimage.Mipmap, vtfimage.LowResImage and vtfimage.Convert.

Supported formats: all 8 bit RGB(A) orderings, 565/5551/4444 packed formats, I8, IA88, A8, blue screen formats, DXT1/DXT3/DXT5, ATI1N/ATI2N, RGBA16161616 and floating point formats (clamped to [0, 1]). P8, UV and depth buffer formats are not supported.

Migrating from v1

• Import github.com/galaco/vtf/v2.
• HighResImageData(), MipmapsForFrame() and HighestResolutionImageForFrame() are replaced by Mipmap(level, frame, face, slice), MipmapCount(), FrameCount(), FaceCount() and MipmapDimensions(). Mipmap level 0 is now the largest, where v1 indexed mipmaps smallest first.
• Header.Flags is vtf.Flags, and Header.HighResImageFormat/LowResImageFormat are format.Format. Use uint32(...) where a plain integer is needed, and Flags.Has to test flags.
• Errors are named ErrX rather than ErrorX, e.g. ErrSignatureMismatch, ErrMipmapSizeMismatch.
• FlagSRGB is now 0x40; v1 incorrectly defined it as 0xFFFF.

Whats missing

• Modify/export functionality
• Depth buffer formats (NV_DST16 etc.), which are only used for render targets

Contributing

No where near all the possible texture configurations have been tested. It's possible some could cause issues. Any issues (including offending file) are greatly appreciated.