OES_texture_half_float_linear
OES_texture_float_linear

GL_OES_texture_half_float_linear, GL_OES_texture_float_linear

Copyright (c) 2005-2014 The Khronos Group Inc. Copyright terms at
    http://www.khronos.org/registry/speccopyright.html

Khronos-approved extension specifications are updated in response to
issues and bugs prioritized by the Khronos OpenGL ES Working Group. For
extensions which have been promoted to a core Specification, fixes will
first appear in the latest version of that core Specification, and will
eventually be backported to the extension document. This policy is
described in more detail at
    https://www.khronos.org/registry/OpenGL/docs/update_policy.php

Please refer to the ARB_texture_float extension.

Ratified by the Khronos BOP, July 22, 2005.

Revision 3, September 21, 2018

OpenGL ES Extension #35

This extension is written against the OpenGL ES 2.0 Specification.

This extension is derived from the ARB_texture_float extension.

Either
 - OES_texture_half_float and OES_texture_float are required.
or
 - OpenGL ES 3.0 is required.

These extensions expand upon the OES_texture_half_float and
OES_texture_float extensions by allowing support for LINEAR
magnification filter and LINEAR, NEAREST_MIPMAP_LINEAR,
LINEAR_MIPMAP_NEAREST and LINEAR_MIPMAP_NEAREST minification
filters.

When implemented against OpenGL ES 3.0 or later versions, the
existing sized 32-bit floating-point formats become texture-filterable,
but no new formats are added.

Modify Table 3.13, Correspondence of sized internal color formats to base internal format:

Check the ``Texture-filterable'' column for the R32F, RG32F, RGB32F, and RGBA32F formats.

  OES_texture_float was written against OpenGL ES 2.0 and adds a set of
  new unsized formats, including floating-point versions of LUMINANCE and
  LUMINANCE_ALPHA formats.

  OES_texture_float_linear and OES_texture_half_float_linear makes these
  formats filterable for FLOAT and HALF_FLOAT_OES types, respectively.

  OpenGL ES 3.0 added sized internal formats. The unsized formats and
  the LUMINANCE formats are considered legacy formats. Floating point
  versions of these formats were therefore not added in OpenGL ES 3.0.

  Further, OpenGL ES 3.0 requires that the required floating-point
  formats with 16-bits per component ('half-float') are filterable, but
  does not support filtering for floating-point formats with 32-bits per
  component.

  Some OpenGL ES 3.0 implementations want a way to indicate that the
  required floating-point formats with 32-bit per component are also
  filterable _without_ adding the additional unsized formats from
  OES_texture_float. This is achieved by exposing this extension without
  exposing OES_texture_float.

  For an OpenGL ES 3.0 implementation, the following holds for the
  combination of the OES_texture_float, OES_texture_float_linear,
  and OES_texture_half_float_linear extensions:

    - If none of these extensions are supported:
       - floating-point formats with 32-bit per component are not filterable
       - floating-point formats with 16-bit per component are filterable

    - If OES_texture_float_linear is supported:
       - all floating-point formats in Table 3.13 are filterable

    - If OES_texture_float and OES_texture_float_linear are supported:
       - all floating-point formats in Table 3.13 are filterable
       - all formats of type FLOAT added by OES_texture_float are filterable

    - If OES_texture_half_float and OES_texture_half_float_linear are
       supported:
       - all floating-point formats in Table 3.13 are filterable
       - all formats of type HALF_FLOAT_OES added by OES_texture_half_float
         are filterable

07/06/2005  0.1   Original draft

10/29/2014  2     Add interactions with ES 3.0/3.1.

09/21/2018  3     Clarified interactions with ES 3.x.