NAME

       clCreateFromGLTexture - Creates an OpenCL image object, image array object, or image
       buffer object from an OpenGL texture object, texture array object, texture buffer object,
       or a single face of an OpenGL cubemap texture object.

       cl_mem clCreateFromGLTexture(cl_context context, cl_mem_flags flags,
                                    GLenum texture_target, GLint miplevel, GLuint texture,
                                    cl_int * errcode_ret);

PARAMETERS

        context
           A valid OpenCL context created from an OpenGL context.

        flags
           A bit-field that is used to specify usage information. Refer to the table for
           clCreateBuffer(3clc)for a description of flags. Only the values CL_MEM_READ_ONLY,
           CL_MEM_WRITE_ONLY and CL_MEM_READ_WRITE can be used.

        texture_target
           texture_target This value must be one of GL_TEXTURE_1D, GL_TEXTURE_1D_ARRAY,
           GL_TEXTURE_BUFFER, GL_TEXTURE_2D, GL_TEXTURE_2D_ARRAY, GL_TEXTURE_3D,
           GL_TEXTURE_CUBE_MAP_POSITIVE_X, GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
           GL_TEXTURE_CUBE_MAP_POSITIVE_Z, GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
           GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or
           GL_TEXTURE_RECTANGLE. This requires OpenGL 3.1. Alternatively,
           GL_TEXTURE_RECTANGLE_ARB may be specified if the OpenGL extension
           GL_ARB_texture_rectangle is supported.  texture_target is used only to define the
           image type of texture. No reference to a bound GL texture object is made or implied by
           this parameter.

        miplevel
           The mipmap level to be used. If texture_target is GL_TEXTURE_BUFFER, miplevel must be
           0. Implementations may return CL_INVALID_OPERATION for miplevel values > 0

        texture
           The name of a GL 1D, 2D, 3D, 1D array, 2D array, cubemap, rectangle or buffer texture
           object. The texture object must be a complete texture as per OpenGL rules on texture
           completeness. The texture format and dimensions defined by OpenGL for the specified
           miplevel of the texture will be used to create the OpenCL image memory object. Only GL
           texture objects with an internal format that maps to appropriate image channel order
           and data type specified in tables 5.5 and 5.6 may be used to create the OpenCL image
           memory object.

        errcode_ret
           Returns an appropriate error code as described below. If errcode_ret is NULL, no error
           code is returned.

NOTES

       If the state of a GL texture object is modified through the GL API (e.g.  glTexImage2D,
       glTexImage3D or the values of the texture parameters GL_TEXTURE_BASE_LEVEL or
       GL_TEXTURE_MAX_LEVEL are modified) while there exists a corresponding CL image object,
       subsequent use of the CL image object will result in undefined behavior.

       The clRetainMemObject(3clc) and clReleaseMemObject(3clc) functions can be used to retain
       and release the image objects.

ERRORS

       Returns a valid non-zero OpenCL image object and errcode_ret is set to CL_SUCCESS if the
       image object is created successfully. Otherwise, it returns a NULL value with one of the
       following error values returned in errcode_ret:

       ·   CL_INVALID_CONTEXT if context is not a valid context or was not created from a GL
           context.

       ·   CL_INVALID_VALUE if values specified in flags are not valid or if value specified in
           texture_target is not one of the values specified in the description of
           texture_target.

       ·   CL_INVALID_MIP_LEVEL if miplevel is less than the value of levelbase (for OpenGL
           implementations) or zero (for OpenGL ES implementations); or greater than the value of
           q (for both OpenGL and OpenGL ES). levelbase and q are defined for the texture in
           section 3.8.10 (Texture Completeness) of the OpenGL 2.1 specification and section
           3.7.10 of the OpenGL ES 2.0.

       ·   CL_INVALID_MIP_LEVEL if miplevel is greater than zero and the OpenGL implementation
           does not support creating from non-zero mipmap levels.

       ·   CL_INVALID_GL_OBJECT if texture is not a GL texture object whose type matches
           texture_target, if the specified miplevel of texture is not defined, or if the width
           or height of the specified miplevel is zero.

       ·   CL_INVALID_IMAGE_FORMAT_DESCRIPTOR if the OpenGL texture internal format does not map
           to a supported OpenCL image format.

       ·   CL_INVALID_OPERATION if texture is a GL texture object created with a border width
           value greater than zero.

       ·   CL_OUT_OF_RESOURCES if there is a failure to allocate resources required by the OpenCL
           implementation on the device.

       ·   CL_OUT_OF_HOST_MEMORY if there is a failure to allocate resources required by the
           OpenCL implementation on the host.

SPECIFICATION

       OpenCL Specification[1]

SEE ALSO

       obsolete page replaced by clCreateFromGLTexture

       cl_khr_gl_sharing(3clc), clCreateBuffer(3clc), clCreateFromGLTexture(3clc)

AUTHORS

       The Khronos Group

COPYRIGHT

       Copyright © 2007-2011 The Khronos Group Inc.
       Permission is hereby granted, free of charge, to any person obtaining a copy of this
       software and/or associated documentation files (the "Materials"), to deal in the Materials
       without restriction, including without limitation the rights to use, copy, modify, merge,
       publish, distribute, sublicense, and/or sell copies of the Materials, and to permit
       persons to whom the Materials are furnished to do so, subject to the condition that this
       copyright notice and permission notice shall be included in all copies or substantial
       portions of the Materials.

NOTES

        1. OpenCL Specification
           page 50, section 9.7.3 - CL Image Objects -> GL Textures