11 Last Modifed Date: Apr 30, 2014
15 OpenGL ES 2.0 is required.
19 This extension allows for more efficient uploading of texture data through
20 Chromium's OpenGL ES 2.0 implementation as well as enable hardware overlay
21 support by providing ability to create buffers capable of being scanned out
22 directly by the display controller.
24 For security reasons Chromium accesses the GPU from a separate process. User
25 processes are not allowed to access the GPU directly. This multi-process
26 architechure has the advantage that GPU operations can be secured and
27 pipelined but it has the disadvantage that all data that is going to be
28 passed to GPU must first be made available to the separate GPU process.
30 This extension helps the application directly allocate and access texture
39 Accepted by the <pname> parameter of GetImageParameterivCHROMIUM:
41 IMAGE_ROWBYTES_CHROMIUM 0x78F0
43 Accepted by the <usage> parameter of CreateImageCHROMIUM:
45 IMAGE_MAP_CHROMIUM 0x78F1
46 IMAGE_SCANOUT_CHROMIUM 0x78F2
48 New Procedures and Functions
50 GLuint CreateImageCHROMIUM(GLsizei width, GLsizei height,
51 GLenum internalformat, GLenum usage)
53 Allocate an image with width equal to <width> and height equal
54 to <height> stored in format <internalformat>.
56 Returns a unique identifier for the allocated image that could be used
57 in subsequent operations.
59 INVALID_VALUE is generated if <width> or <height> is nonpositive.
61 INVALID_ENUM is generated if <usage> is not one of
62 IMAGE_MAP_CHROMIUM and IMAGE_SCANOUT_CHROMIUM.
64 void DestroyImageCHROMIUM(GLuint image_id)
66 Frees the image previously allocated by a call to CreateImageCHROMIUM.
68 INVALID_OPERATION is generated if <image_id> is not a valid image id.
70 void* MapImageCHROMIUM(GLuint image_id)
72 Returns a pointer to in the user memory for the application to modify
73 the image. It is illegal to call this function on an image not created
74 with IMAGE_MAP_CHROMIUM usage.
76 INVALID_OPERATION is generated if <image_id> is not a valid image id.
78 INVALID_OPERATION is generated if the image was already mapped by a previous
81 void UnmapImageCHROMIUM(GLuint image_id)
83 Removes the mapping created by a call to MapImageCHROMIUM.
85 Note that after calling UnmapImageCHROMIUM the application should assume
86 that the memory returned by MapImageCHROMIUM is off limits and is no longer
87 accessible by the application. Accessing it after calling
88 UnmapImageCHROMIUM will produce undefined results.
90 INVALID_OPERATION is generated if <image_id> is not a valid image id.
92 INVALID_OPERATION is generated if the image was not already mapped by a
93 previous call to MapImageCHROMIUM.
95 void GetImageParameterivCHROMIUM(GLuint image_id, GLenum pname,
98 Sets <params> to the integer value of the parameter specified by <pname>
99 for the image specified by <image_id>. <params> is expected to be
100 properly allocated before calling this method.
102 INVALID_OPERATION is generated if <image_id> is not a valid image id.
104 INVALID_ENUM is generated if <pname> is not IMAGE_ROWBYTES_CHROMIUM.
116 5/9/2013 Documented the extension
117 4/30/2014 Moved usage flag to creation function.