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Re: [Public WebGL] KTX file format

Ericsson's intent is that the code be usable for purposes related to Khronos Group APIs which WebGL surely is. I see that the license as currently written would not cover WebGL on D3D. This case is very similar to using the decompressor in a software implementation of OpenGL ES which they definitely intended to be permissible. So I am confident we can get Ericsson to amend the license. Thanks for pointing out the problem.



On 2010/08/06 11:17, Chris Marrin wrote:
On Aug 6, 2010, at 10:56 AM, Mark Callow wrote:

Some time ago there was discussion on this list downloading textures in a compressed format. Well last week at Siggraph, Khronos announced the KTX file format and tools.

KTX (Khronos Texture) is a lightweight file format for OpenGL® textures, designed around how textures are loaded in OpenGL. KTX files contain all the parameters needed for texture loading. A single file can contain everything from a simple base-level 2D texture through to an array texture with all mipmap levels. Textures can be stored in one of the compressed formats, e.g. ETC1, supported by OpenGL family APIs and extensions or can be stored uncompressed.

We expect most texture compression tools will add support for KTX and we expect ETC (Ericsson Texture Compression) to become more widely available in the future. Thus together these two standards will ultimately provide a solution to downloading compressed texture data for WebGL.
It's sad that ETC1 has a oppressive license (http://www.khronos.org/opengles/sdk/tools/KTX/doc/libktx/licensing.html) which will probably make it unusable for most WebGL implementations. IANAL, but it looks to me like an implementation of WebGL on top of D3D will not be able to use ETC1, since it would not be "a middleware API that is built on top of a Khronos API". 

Too bad.



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