Name

    OHOS_image_native_buffer

Name Strings

    EGL_OHOS_image_native_buffer

Contributors

    Xindong Shi
    Zheng Li

Contact

    Xindong Shi, Huawei Inc. (shixindong 'at' huawei.com)
    Zheng Li, Huawei Inc. (lizheng2 'at' huawei.com)

Status

    Complete

Version

    Version 1, Dec. 14, 2021

Number

    EGL Extension #148

Dependencies

    EGL 1.2 is required.

    EGL_KHR_image_base is required.

    This extension is written against the wording of the EGL 1.2
    Specification.

Overview

    This extension enables using a Openharmony native buffer (struct
    HNativeWindowBuffer) as an EGLImage source.

New Types

    None.

New Procedures and Functions

    None.

New Tokens

    Accepted by the <target> parameter of eglCreateImageKHR:

    EGL_NATIVE_BUFFER_OHOS             0x34E1

Changes to Chapter 3 of the EGL 1.2 Specification (EGL Functions and Errors)

    Add to section 2.5.1 "EGLImage Specification" (as defined by the
    EGL_KHR_image_base specification), in the description of
    eglCreateImageKHR:

   "Values accepted for <target> are listed in Table aaa, below.

      +-------------------------+---------------------------------------------------+
      | <target>                | Notes                                             |
      +-------------------------+---------------------------------------------------+
      | EGL_NATIVE_BUFFER_OHOS  | Used for Openharmony HNativeWindowBuffer objects  |
      +-------------------------+---------------------------------------------------+
       Table aaa.  Legal values for eglCreateImageKHR <target> parameter

    ...

    If <target> is EGL_NATIVE_BUFFER_OHOS, <dpy> must be a valid display,
    <ctx> must be EGL_NO_CONTEXT, <buffer> must be a pointer to a valid
    HNativeWindowBuffer object (cast into the type EGLClientBuffer), and
    attributes other than EGL_IMAGE_PRESERVED_KHR are ignored."

    Add to the list of error conditions for eglCreateImageKHR:

      "* If <target> is EGL_NATIVE_BUFFER_OHOS and <buffer> is not a
         pointer to a valid HNativeWindowBuffer, the error EGL_BAD_PARAMETER
         is generated.

       * If <target> is EGL_NATIVE_BUFFER_OHOS and <ctx> is not
         EGL_NO_CONTEXT, the error EGL_BAD_CONTEXT is generated.

       * If <target> is EGL_NATIVE_BUFFER_OHOS and <buffer> was created
         with properties (format, usage, dimensions, etc.) not supported by
         the EGL implementation, the error EGL_BAD_PARAMETER is generated."

Issues

    1. Should this extension define what combinations of HNativeWindowBuffer
    properties implementations are required to support?

    RESOLVED: No.

    The requirements have evolved over time and will continue to change with
    future Openharmony releases. The minimum requirements for a given Openharmony
    version should be documented by that version.


Revision History

#1 (Xindong Shi, Zheng Li, Dec. 14, 2021)
    - Initial draft.