gpu/GLES2/extensions/CHROMIUM/CHROMIUM_subscribe_uniform.txt

Name

    CHROMIUM_subscribe_uniform

Name Strings

    CHROMIUM_subscribe_uniform

Version

    Last Modifed Date: October 30, 2014

Dependencies

    OpenGL ES 2.0 is required.

Overview

    Allows clients to subscribe to a set of input uniforms which can
    be populated within buffers and used to modify uniform variables within
    their programs.

    Decreases percieved latency for operations performed against these
    uniforms.

New Tokens

    Accepted by the <target> parameter of glBindValueBufferCHROMIUM,
    glSubscribeValueCHROMIUM, glPopulateSubscribedValuesCHROMIUM and
    glUniformValueBufferCHROMIUM

    GL_SUBSCRIBED_VALUES_BUFFER_CHROMIUM                        0x924B

    Accepted by the <subscription> parameter of glSubscribeValueCHROMIUM and
    glUniformValueBufferCHROMIUM:

    GL_MOUSE_POSITION_CHROMIUM                                  0x924C

New Procedures and Functions

    The command

       void glGenValuebuffersCHROMIUM(GLsizei n, GLuint* buffers)

    Generates value buffer object names.
    <n> Specifies the number of value buffer object names to be generated.
    <buffers> Specifies an array in which the generated value buffer object 
              names are stored.

   The command

      void glDeleteValuebuffersCHROMIUM(GLsizei n, const GLuint* valuebuffers)

   Deletes named value buffer objects.
   <n> Specifies the number of value buffer objects to be deleted.
   <buffers> Specifies an array of value buffer objects to be deleted.

   The command

      boolean glIsValuebufferCHROMIUM(GLuint buffer);

   Returns whether an object is a value buffer object.
   <buffer> Specifies the name of a buffer object.

   The command

      void glBindValuebufferCHROMIUM(GLenum target, GLuint buffer);

   Lets you use a named value buffer object.
   <target> Specifies the target to which the buffer object is bound.
   <buffer> Specifies the name of a buffer object.

   The command

      void glSubscribeValueCHROMIUM(GLenum target, GLenum subscription)

   Subscribes the currently bound buffer object to a subscription target.
   <target> Specifies the target to which the buffer object is bound.
   <subscription> Specifies the subscription to which the currently bound
                  buffer object should be subscribed.

   The command

      void glPopulateSubscribedValuesCHROMIUM(GLenum target)

   Populates the currently bound buffer object with all subscription states
   to which it is subscribed.
   <target> Specifies the target to which the buffer object is bound.

   The command
 
      void glUniformValueBufferCHROMIUM(GLint location, GLenum target,
                                       GLenum subscription)

   Populates the uniform specified by location within the currently bound
   program with the value in the currently bound buffer for the subscription
   target.
   <location> Specifies the location of the uniform variable to by modified.
   <target> Specifies the target to which the buffer object is bound.
   <subscription> Specifies the subscription in the currently bound buffer
                  whose value should be used to populate the uniform.

Errors

    None.

New State

    None.

Revision History

    10/30/2014    Documented the extension