1Name
2
3    ANGLE_display_semaphore_share_group
4
5Name Strings
6
7    EGL_ANGLE_display_semaphore_share_group
8
9Contributors
10
11    Peng Huang, Google
12
13Contacts
14
15    Peng Huang, Google (penghuang 'at' google.com)
16
17Status
18
19    Draft
20
21Version
22
23    Version 1, July 27, 2020
24
25Number
26
27    EGL Extension TBD
28
29Dependencies
30
31    This extension is written against the wording of the EGL 1.5 specification.
32
33Overview
34
35    This extension allows for the creation of OpenGL ES contexts that share
36    semaphore objects with other contexts owned by the same display. This method
37    of sharing semaphores can be used in conjuction with regular share groups.
38
39New Types
40
41    None
42
43New Procedures and Functions
44
45    None
46
47New Tokens
48
49    Accepted as an attribute name in the <*attrib_list> argument to
50    eglCreateContext:
51
52        EGL_DISPLAY_SEMAPHORE_SHARE_GROUP_ANGLE    0x348D
53
54Additions to the EGL 1.5 Specification
55
56    Add a new section entitled "OpenGL ES Global Semaphore Share Groups"
57    to section 3.7.1:
58
59    "If the attribute EGL_DISPLAY_SEMAPHORE_SHARE_GROUP_ANGLE is set to EGL_TRUE,
60    a context that shares semaphores with other contexts owned by the same
61    display and created with EGL_DISPLAY_SEMAPHORE_SHARE_GROUP_ANGLE set to
62    EGL_TRUE will be created. If the share_context parameter to
63    eglCreateContext is not NULL, all contexts within the share group must have
64    been created with the same value of EGL_DISPLAY_SEMAPHORE_SHARE_GROUP_ANGLE.
65    The default value of EGL_DISPLAY_SEMAPHORE_SHARE_GROUP_ANGLE is EGL_FALSE."
66
67Issues
68
69    (1) What happens to the shared semaphores when a context in the global share
70        group is destroyed?
71
72    RESOLOVED: When the last context in the global semaphore share group is
73    destroyed, all semaphores in the global semaphore share group are released. If
74    a new context is created in the global semaphore share group, no semaphores
75    will exist.
76
77    This mirrors how regular share groups work, releasing all objects when the
78    last context is destroyed.
79
80Revision History
81
82    Version 1, 2020/07/27 - first draft.
83