| Name |
| |
| SGIX_depth_texture |
| |
| Name Strings |
| |
| GL_SGIX_depth_texture |
| |
| Version |
| |
| $Date: 1997/02/26 03:36:29 $ $Revision: 1.5 $ |
| |
| Number |
| |
| 63 |
| |
| Dependencies |
| |
| EXT_texture is required |
| EXT_subtexture affects the definition of this extension |
| EXT_copy_texture affects the definition of this extension |
| |
| Overview |
| |
| This extension defines a new depth texture format. An important |
| application of depth texture images is shadow casting, but separating |
| this from the shadow extension allows for the potential use of depth |
| textures in other applications such as image-based rendering or |
| displacement mapping. This extension does not define new depth-texture |
| environment functions, such as filtering or applying the depth values |
| computed from a texture, but leaves this to other extensions, such as |
| the shadow extension. |
| |
| New Procedures and Functions |
| |
| None |
| |
| New Tokens |
| |
| Accepted by the <components> parameters of TexImage1D and TexImage2D, |
| and by the <internalformat> parameters of TexImage3DEXT, |
| CopyTexImage1DEXT, and CopyTexImage2DEXT: |
| |
| DEPTH_COMPONENT16_SGIX 0x81A5 |
| DEPTH_COMPONENT24_SGIX 0x81A6 |
| DEPTH_COMPONENT32_SGIX 0x81A7 |
| |
| |
| Additions to Chapter 2 of the 1.0 Specification (OpenGL Operation) |
| |
| None |
| |
| Additions to Chapter 3 of the 1.0 Specification (Rasterization) |
| |
| XXX - lots |
| |
| Notes: |
| |
| * Defines DEPTH_COMPONENT as a new base internal format for |
| textures. Defines 16, 24, and 32 bit specific internal formats |
| for texture. Just as for the specific color internal formats, |
| an implementation can choose whether to implement them or not. |
| |
| * Texture commands that accept images from memory now allow the |
| internal format to be DEPTH_COMPONENT or DEPTH_COMPONENT*_SGIX |
| when the format of the image data is DEPTH_COMPONENT. Depth, not |
| color pixel transfer operations are applied to depth images. |
| |
| * Texture commands that accept images from the framebuffer now take |
| their data from the depth buffer when the internal format is |
| DEPTH_COMPONENT or DEPTH_COMPONENT*_SGIX, or when no internal |
| format is specified, and the internal format of the target texture |
| is DEPTH_COMPONENT or DEPTH_COMPONENT*_SGIX. |
| |
| Additions to Chapter 4 of the 1.0 Specification (Per-Fragment Operations |
| and the Frame Buffer) |
| |
| None |
| |
| Additions to Chapter 5 of the 1.0 Specification (Special Functions) |
| |
| None |
| |
| Additions to Chapter 6 of the 1.0 Specification (State and State Requests) |
| |
| None |
| |
| Additions to the GLX Specification |
| |
| None |
| |
| Dependencies on EXT_texture |
| |
| EXT_texture is required. |
| |
| Dependencies on EXT_texture3D |
| |
| EXT_texture3D is not required, but if it is not supported, the |
| implementation must compute the R texture coordinate as if it were. |
| If EXT_texture3D is not supported, references to TexImage3DEXT and |
| TexSubImage3DEXT in this document are invalid and should be ignored. |
| |
| Dependencies on EXT_subtexture |
| |
| If EXT_subtexture is not supported, references to TexSubImage1DEXT, |
| TexSubImage2DEXT, and TexSubImage3DEXT in this document are invalid and |
| should be ignored. If EXT_subtexture is supported, the operations of |
| these three commands are affected by this extension. |
| |
| Dependencies on EXT_copy_texture |
| |
| If EXT_copy_texture is not supported, references to CopyTexImage1DEXT |
| and CopyTexImage2DEXT in this document are invalid and should be |
| ignored. If EXT_copy_texture is supported, the operations of these two |
| commands, and of CopyTexSubImage1DEXT, CopyTexSubImage2DEXT, and |
| CopyTexSubImage3DEXT are affected by this extension. |
| |
| Errors |
| |
| INVALID_OPERATION is generated if TexImage1D or TexImage2D parameter |
| <format> is DEPTH_COMPONENT and parameter <components> is not |
| DEPTH_COMPONENT, DEPTH_COMPONENT16_SGI, DEPTH_COMPONENT24_SGI, or |
| DEPTH_COMPONENT32_SGI. |
| |
| INVALID_OPERATION is generated if TexImage3DEXT parameter <format> is |
| DEPTH_COMPONENT and parameter <internalformat> is not |
| DEPTH_COMPONENT, DEPTH_COMPONENT16_SGI, DEPTH_COMPONENT24_SGI, or |
| DEPTH_COMPONENT32_SGI. |
| |
| INVALID_OPERATION is generated if CopyTexImage1DEXT or CopyTexImage2DEXT |
| parameter <internalformat> is DEPTH_COMPONENT, DEPTH_COMPONENT16_SGI, |
| DEPTH_COMPONENT24_SGI, or DEPTH_COMPONENT32_SGI, and there is no |
| depth buffer. |
| |
| New State |
| |
| None |
| |
| New Implementation Dependent State |
| |
| None |