| Name |
| |
| ANGLE_get_tex_level_parameter |
| |
| Name Strings |
| |
| GL_ANGLE_get_tex_level_parameter |
| |
| Contributors |
| |
| Geoff Lang, Google |
| |
| Contact |
| |
| Geoff Lang (geofflang 'at' google.com) |
| |
| Status |
| |
| Incomplete |
| |
| Version |
| |
| Last Modified Date: Oct 12, 2020 |
| Author Revision: 1 |
| |
| Number |
| |
| OpenGL ES Extension XX |
| |
| Dependencies |
| |
| OpenGL ES 2.0 is required. |
| |
| This extension is written against the OpenGL ES 3.0.6 specification. |
| |
| Overview |
| |
| This extension allows the user to query information about specific texture |
| levels exposed later in OpenGL ES 3.1. |
| |
| IP Status |
| |
| No known IP claims. |
| |
| New Procedures and Functions |
| |
| void GetTexLevelParameter{if}vANGLE(enum target, int level, |
| enum pname, T *params ); |
| |
| New Tokens |
| |
| Accepted by the <pname> parameter of GetTexLevelParameter{if}vANGLE: |
| |
| TEXTURE_WIDTH_ANGLE 0x1000 |
| TEXTURE_HEIGHT_ANGLE 0x1001 |
| TEXTURE_DEPTH_ANGLE 0x8071 |
| TEXTURE_INTERNAL_FORMAT_ANGLE 0x1003 |
| TEXTURE_RED_SIZE_ANGLE 0x805C |
| TEXTURE_GREEN_SIZE_ANGLE 0x805D |
| TEXTURE_BLUE_SIZE_ANGLE 0x805E |
| TEXTURE_ALPHA_SIZE_ANGLE 0x805F |
| TEXTURE_DEPTH_SIZE_ANGLE 0x884A |
| TEXTURE_STENCIL_SIZE_ANGLE 0x88F1 |
| TEXTURE_SHARED_SIZE_ANGLE 0x8C3F |
| TEXTURE_RED_TYPE_ANGLE 0x8C10 |
| TEXTURE_GREEN_TYPE_ANGLE 0x8C11 |
| TEXTURE_BLUE_TYPE_ANGLE 0x8C12 |
| TEXTURE_ALPHA_TYPE_ANGLE 0x8C13 |
| TEXTURE_DEPTH_TYPE_ANGLE 0x8C16 |
| TEXTURE_COMPRESSED_ANGLE 0x86A1 |
| TEXTURE_SAMPLES_ANGLE 0x9106 |
| TEXTURE_FIXED_SAMPLE_LOCATIONS_ANGLE 0x9107 |
| |
| (Note: these tokens are shared with OpenGL ES 3.1.) |
| |
| Returned in <params> by GetTexLevelParameter{if}vANGLE: |
| |
| UNSIGNED_NORMALIZED_ANGLE 0x8C17 |
| SIGNED_NORMALIZED_ANGLE 0x8F9C |
| |
| (Note: these tokens are shared with OpenGL ES 3.0.) |
| |
| Additions to Chapter 6 of the OpenGL ES 3.0.5 Specification (State and State |
| Requests) |
| |
| Modify Section 6.1.4 "Texture Queries": |
| |
| (Add the following text to the end of the section) |
| |
| The commands |
| |
| void GetTexLevelParameter{if}vANGLE(enum target, int level, |
| enum pname, T *params ); |
| |
| place information about texture image parameter <pname> for level-of-detail |
| <level> of the specified <target> into <params>. <pname> must be one of the |
| symbolic values in table 6.10. |
| |
| <target> may be any of the cube map face targets from table 3.21 or any |
| texture target valid for the BindTexture command except TEXTURE_CUBE_MAP. |
| |
| <level> determines which level-of-detail's state is returned. The maximum |
| value of <level> depends on the texture <target>: |
| |
| * For cube map targets, the maximum value is log2 of the value of |
| MAX_CUBE_MAP_TEXTURE_SIZE. |
| |
| * For the 3D texture target, the maximum value is log2 of the value of |
| MAX_3D_TEXTURE_SIZE. |
| |
| * For targets that do not support mipmaps, the maximum value is zero. |
| |
| * For all other texture targets, the maximum value is log2 of the value of |
| MAX_TEXTURE_SIZE. |
| |
| For texture images with uncompressed internal formats, queries of <pname> |
| TEXTURE_RED_TYPE_ANGLE, TEXTURE_GREEN_TYPE_ANGLE, TEXTURE_BLUE_TYPE_ANGLE, |
| TEXTURE_ALPHA_TYPE_ANGLE, and TEXTURE_DEPTH_TYPE_ANGLE return the data type |
| used to store the component. Types NONE, SIGNED_NORMALIZED, UNSIGNED_- |
| NORMALIZED, FLOAT, INT, and UNSIGNED_INT respectively indicate missing, |
| signed normalized fixed-point, unsigned normalized fixed-point, floating- |
| point, signed unnormalized integer, and unsigned unnormalized integer |
| components. Queries of <pname> TEXTURE_RED_SIZE_ANGLE, TEXTURE_GREEN_SIZE_- |
| ANGLE, TEXTURE_BLUE_SIZE_ANGLE, TEXTURE_ALPHA_SIZE_ANGLE, TEXTURE_DEPTH_- |
| SIZE_ANGLE, TEXTURE_STENCIL_SIZE_ANGLE, and TEXTURE_SHARED_SIZE_ANGLE return |
| the actual resolutions of the stored image components, not the resolutions |
| specified when the image was defined. |
| |
| For texture images with compressed internal formats, the types returned |
| specify how components are interpreted after decompression, while the |
| resolutions returned specify the component resolution of an uncompressed |
| internal format that produces an image of roughly the same quality as the |
| compressed image in question. Since the quality of the implementation's |
| compression algorithm is likely data-dependent, the returned component sizes |
| should be treated only as rough approximations. |
| |
| Queries of <pname> TEXTURE_INTERNAL_FORMAT_ANGLE, TEXTURE_WIDTH_ANGLE, |
| TEXTURE_HEIGHT_ANGLE, and TEXTURE_DEPTH_ANGLE return the internal format, |
| width, height, and depth, respectively, as specified when the texture image |
| was created. Queries of <pname> TEXTURE_DEPTH_ANGLE return 1 if the created |
| image has neither 3D slices nor array layers. |
| |
| Queries of <pname> TEXTURE_SAMPLES_ANGLE, and TEXTURE_FIXED_SAMPLE_- |
| LOCATIONS_ANGLE on multisample textures return the number of samples and |
| whether texture sample fixed locations are enabled, respectively. |
| For non-multisample textures, the default values in table 6.10 are returned. |
| |
| Errors |
| |
| The error INVALID_ENUM is generated by GetTexLevelParameter{if}vANGLE |
| if <target> is not one of the texture targets described above. |
| |
| The error INVALID_VALUE is generated by GetTexLevelParameter{if}vANGLE |
| if <level> is negative or larger than the maximum allowable level-of-detail. |
| |
| The error INVALID_ENUM is generated by GetTexLevelParameter{if}vANGLE |
| if <pname> is not one of the symbolic values in table 6.10. |
| |
| Interactions with OpenGL ES 3.1 |
| |
| If this extension is exposed on OpenGL ES 3.1 or higher context versions, |
| the GetTexLevelParameter{if}vANGLE commands become identical to the core |
| GetTexLevelParameter{if}v commands. |
| |
| Interactions with OpenGL ES 3.0 |
| |
| If this extension is exposed on OpenGL ES 3.0, which does not support |
| multisample textures, queries with the TEXTURE_SAMPLES_ANGLE and |
| TEXTURE_FIXED_SAMPLE_LOCATIONS_ANGLE parameters are still valid. |
| |
| If multisample textures are supported via additional extensions, such as |
| ANGLE_texture_multisample, queries with these parameters return |
| corresponding parameter values for multisample textures. |
| |
| Interactions with OpenGL ES 2.0 |
| |
| If this extension is exposed on OpenGL ES 2.0, which does not support |
| multisample textures, 2D array and 3D textures, depth textures, combined |
| depth-stencil textures, and the shared-exponent internal format, queries |
| with the TEXTURE_SAMPLES_ANGLE, TEXTURE_FIXED_SAMPLE_LOCATIONS_ANGLE, |
| TEXTURE_DEPTH_ANGLE, TEXTURE_DEPTH_SIZE_ANGLE, TEXTURE_STENCIL_SIZE_ANGLE, |
| and TEXTURE_SHARED_SIZE_ANGLE parameters are still valid. |
| |
| If 3D textures are supported via additional extensions, such as |
| OES_texture_3d, queries with the TEXTURE_DEPTH_ANGLE parameter return |
| corresponding depth values for 3D textures. |
| |
| If depth textures are supported via additional extensions, such as |
| OES_depth_texture, queries with the TEXTURE_DEPTH_SIZE_ANGLE and |
| TEXTURE_DEPTH_TYPE_ANGLE parameters return corresponding resolutions |
| and types of the depth component. |
| |
| If combined depth-stencil textures are supported via additional extensions, |
| such as OES_packed_depth_stencil, queries with the TEXTURE_STENCIL_SIZE_- |
| ANGLE parameter return corresponding resolutions of the stencil |
| component. |
| |
| If the shared-exponent internal format is supported via additional |
| extensions, such as APPLE_texture_packed_float, queries with the TEXTURE_- |
| SHARED_SIZE_ANGLE parameter return corresponding resolutions of the |
| shared-exponent component. |
| |
| If this extension is exposed on OpenGL ES 2.0, the enums denoting the |
| normalized component types can be taken from this extension as they are not |
| defined in OpenGL ES 2.0 headers. |
| |
| New State |
| |
| (add new table 6.10, Textures (state per texture image), renumber subsequent tables) |
| |
| Initial |
| Get Value Type Get Command Value Description Sec. |
| ----------------------------- ---- --------------------------- ------- --------------------------- ------ |
| TEXTURE_WIDTH_ANGLE Z+ GetTexLevelParameterivANGLE 0 Specified width 3.8 |
| TEXTURE_HEIGHT_ANGLE Z+ GetTexLevelParameterivANGLE 0 Specified height (2D/3D) 3.8 |
| TEXTURE_DEPTH_ANGLE Z+ GetTexLevelParameterivANGLE 0 Specified depth (3D) 3.8 |
| TEXTURE_INTERNAL_FORMAT_ANGLE E GetTexLevelParameterivANGLE RGBA Internal format 3.8 |
| (see section 3.8.14) |
| TEXTURE_x_SIZE_ANGLE 6xZ+ GetTexLevelParameterivANGLE 0 Component resolution (x is 3.8 |
| RED, GREEN, BLUE, ALPHA, |
| DEPTH, or STENCIL) |
| TEXTURE_SHARED_SIZE_ANGLE Z+ GetTexLevelParameterivANGLE 0 Shared exponent field 3.8 |
| resolution |
| TEXTURE_x_TYPE_ANGLE E GetTexLevelParameterivANGLE NONE Component type (x is RED, 6.1.4 |
| GREEN, BLUE, ALPHA, or |
| DEPTH) |
| TEXTURE_COMPRESSED_ANGLE B GetTexLevelParameterivANGLE FALSE True if image has a 3.8.6 |
| compressed internal format |
| TEXTURE_SAMPLES_ANGLE Z+ GetTexLevelParameterivANGLE 0 Number of samples per texel |
| TEXTURE_FIXED_SAMPLE_- B GetTexLevelParameterivANGLE TRUE Whether the image uses |
| LOCATIONS_ANGLE a fixed sample pattern |
| |
| Issues |
| None |
| |
| Revision History |
| |
| Rev. Date Author Changes |
| ---- -------- ---------- -------------------------------------------- |
| 1 14/10/20 Geoff Lang First revision. Adapted from OpenGL ES |
| specification 3.1. |
