| Name |
| |
| INGR_interlace_read |
| |
| Name Strings |
| |
| GL_INGR_interlace_read |
| |
| Version |
| |
| Date: 12/14/98 Revision: 1.0 |
| |
| Number |
| |
| 175 |
| |
| Dependencies |
| |
| None |
| |
| Overview |
| |
| This extension provides a way to skip rows of pixels when reading |
| or copying pixel rectangles. This extension is complementary to |
| the EXT_interlace extension except that it has no affect on getting |
| texture images. |
| |
| New Procedures and Functions |
| |
| None |
| |
| New Tokens |
| |
| Accepted by the <cap> parameter of of Enable, Disable, IsEnabled, and |
| by the <pname> parameter of GetBooleanv, GetIntegerv, GetFloatv, |
| GetDoublev: |
| |
| INTERLACE_READ_INGR 0x8568 |
| |
| Additions to Chapter 2 of the 1.2 Specification (OpenGL Operation) |
| |
| None |
| |
| Additions to Chapter 3 of the 1.2 Specification (Rasterization) |
| |
| None |
| |
| Additions to Chapter 4 of the 1.2 Specification (Per-Fragment Operations |
| and the Frame Buffer) |
| |
| [In section 4.3.2 "Reading Pixels" the specification of an interlace |
| read operation is added to the GL Specification in the sectino on |
| "Obtaining Pixels from the FrameBuffer."] |
| |
| Reading interlaced rows of pixels is enabled or disabled with Enable |
| or Disable using the symbolic constant INTERLACE_READ_INGR. If |
| INTERLACE_READ_INGR is disabled, then ReadPixels obtains values from |
| the selected buffer from each pixel with lower left hand corner at |
| (x+i, y+j) for 0 <= i < width and 0 <= j < height; this pixel is said |
| to be the ith pixel in the jth row. |
| |
| If INTERLACE_READ_INGR is enabled, then ReadPixels obtains values |
| from the selected buffer from each pixel with lower left hand corner |
| at (x+i, y+(j*2)) for 0 <= i < width and 0 <= j < height; this pixel |
| is said to be the ith pixel in the jth row. |
| |
| If any of these pixels lies outside of the window... |
| |
| Additions to Chapter 5 of the 1.2 Specification (Special Functions) |
| |
| None |
| |
| Additions to Chapter 6 of the 1.2 Specification (State and State Requests) |
| |
| None |
| |
| Additions to the GLX Specification |
| |
| None |
| |
| Errors |
| |
| None |
| |
| New State |
| |
| Get Value Get Command Type Initial Value Attribute |
| -------------------- --------------- ----- -------------- ------------- |
| INTERLACE_READ_INGR IsEnabled B False pixel/enable |
| |
| New Implementation Dependent State |
| |
| None |
