extensions: add MESA_EGL_image_cubemap

extensions/MESA/MESA_EGL_image_cubemap.txt

@@ -0,0 +1,106 @@
+Name
+
+    MESA_EGL_image_cubemap
+
+Name Strings
+
+    GL_MESA_EGL_image_cubemap
+
+Contact
+
+    Simon Zeni, Status Holdings Ltd. <[email protected]>
+
+Contributors
+
+    Simon Zeni
+
+Status
+
+    Draft
+
+Version
+
+    Version 0.1, 2022/08/05
+
+Number
+
+    OpenGL ES Extension #546
+
+Dependencies
+
+    OpenGL ES 2.0 is required, or any previous version that offers support
+    for GL_ARB_texture_cube_map extension
+
+    GL_OES_EGL_image is required.
+
+    EGL 1.2 is required, with the EGL_KHR_image or EGL_KHR_image_base
+
+    This extension is written based on the wording of the OpenGL 2.0
+
+Overview
+
+    This extension provides a mechanism for creating cubemap textures from
+    EGLImage objects.
+
+    MESA_gl_texture_cubemap_image defines the process of creating an EGLImage
+    from an OpenGL ES cubemap texture.
+
+    The companion EGL_KHR_image_base and EGL_KHR_image extensions provide the
+    definition and rationale for EGLImage objects.
+
+    EGL extension specifications are located in the EGL Registry at
+            http://www.khronos.org/registry/egl/
+
+New Tokens
+
+    None.
+
+New Procedures and Functions
+
+    void EGLImageTargetCubemapMESA(enum target, eglImageOES image)
+
+Additions to Chapter 3 of the OpenGL 2.0 Specification (Rasterization)
+
+    In section 3.8.2 following the specification added by OES_EGL_image:
+
+    "It is also possible to specify cubemap textures images from existing
+    EGLImage objects. Images specified this way will be EGLImage sibilings
+    with the original EGLImage source and any other EGLImage targets.
+
+    The command
+
+        void EGLImageTargetCubemapMESA(enum target, eglImageOES image);
+
+    defines an complete cubemap texture with 6 faces. All properties of the
+    texture images (including width, height, format, border, mipmap levels of
+    detail, and image data) are taken from the specified eglImageOES <image>,
+    rather than from the client or the framebuffer.  Any existing image arrays
+    associated with any mipmap levels in the texture object are freed (as if
+    TexImage was called for each, with an image of zero size). As a result of
+    this referencing operation, all of the pixel data in the <buffer> used as
+    the EGLImage source resource (i.e., the <buffer> parameter passed to the
+    CreateImageOES command that returned <image>) will become undefined.
+
+    <target> must be TEXTURE_CUBE_MAP, and <image> must be the handle of a
+    valid EGLImage resource, cast into the type eglImageOES. Assuming no
+    errors are generated by the command EGLImageTargetCubemapMESA, the newly
+    specified texture object will be an EGLImage target of the specified
+    eglImageOES. If an application later respecifies any face of the cubemap
+    texture object (through mechanism such as calls to TexImage2D or
+    TexSubImage2D), the implementation must allocate a new space for the image
+    and copy any existing data to the newly (re)specified texture object. The
+    (re)specified texture object will not be an EGLImage target.
+
+    If the GL is unable to specify a texture object using the supploed
+    eglImageOES <image> (if the <image> refers to a different type of image,
+    such as a TEXTURE_2D), the error INVALID_OPERATION is generated.
+
+    If <image> does not refer to a valid eglImageOES object, the error
+    INVALID_VALUE is generated.
+
+    If <target> is not TEXTURE_CUBE_MAP, the error INVALID_ENUM is generated.
+
+Revision History
+
+    Version 0.1, 2022-08-05 (Simon Zeni)
+            - Initial draft

extensions/glext.php

@@ -1031,6 +1031,8 @@
 </li>
 <li value=546><a href="extensions/EXT/EXT_EGL_sync.txt">GL_EXT_EGL_sync</a>
 </li>
+<li value=546><a href="extensions/MESA/MESA_EGL_image_cubemap.txt">GL_MESA_EGL_image_cubemap</a>
+</li>
 <li value=547><a href="extensions/INTEL/INTEL_shader_integer_functions2.txt">GL_INTEL_shader_integer_functions2</a>
 </li>
 <li value=548><a href="extensions/MESA/MESA_framebuffer_flip_x.txt">GL_MESA_framebuffer_flip_x</a>

extensions/registry.py

@@ -5684,4 +5684,10 @@
         'supporters' : { 'NVIDIA' },
         'url' : 'extensions/NV/GLX_NV_multigpu_context.txt',
     },
+    'GL_MESA_EGL_image_cubemap' : {
+        'number' : 546,
+        'flags' : { 'public' },
+        'supporters' : { 'MESA' },
+        'url' : 'extensions/MESA/MESA_EGL_image_cubemap.txt',
+    },
 }