| Brian Paul | 09b00c5 | 2003-05-01 19:12:23 +0000 | [diff] [blame] | 1 | Name |
| 2 | |
| 3 | MESA_swap_control |
| 4 | |
| 5 | Name Strings |
| 6 | |
| 7 | GLX_MESA_swap_control |
| 8 | |
| 9 | Contact |
| 10 | |
| 11 | Ian Romanick, IBM (idr 'at' us.ibm.com) |
| 12 | |
| 13 | Status |
| 14 | |
| 15 | Deployed in DRI drivers post-XFree86 4.3. |
| 16 | |
| 17 | Version |
| 18 | |
| 19 | Date: 3/17/2003 Revision: 1.0 |
| 20 | |
| 21 | Number |
| 22 | |
| 23 | ??? |
| 24 | |
| 25 | Dependencies |
| 26 | |
| 27 | None |
| 28 | |
| 29 | Based on GLX_SGI_swap_control version 1.9 and WGL_EXT_swap_control |
| 30 | version 1.5. |
| 31 | |
| 32 | Overview |
| 33 | |
| 34 | This extension allows an application to specify a minimum periodicity |
| 35 | of color buffer swaps, measured in video frame periods. |
| 36 | |
| 37 | New Procedures and Functions |
| 38 | |
| 39 | int glXSwapIntervalMESA(int interval) |
| 40 | int glXGetSwapIntervalMESA(void) |
| 41 | |
| 42 | New Tokens |
| 43 | |
| 44 | None |
| 45 | |
| 46 | Additions to Chapter 2 of the 1.4 GL Specification (OpenGL Operation) |
| 47 | |
| 48 | None |
| 49 | |
| 50 | Additions to Chapter 3 of the 1.4 GL Specification (Rasterization) |
| 51 | |
| 52 | None |
| 53 | |
| 54 | Additions to Chapter 4 of the 1.4 GL Specification (Per-Fragment Operations |
| 55 | and the Framebuffer) |
| 56 | |
| 57 | None |
| 58 | |
| 59 | Additions to Chapter 5 of the 1.4 GL Specification (Special Functions) |
| 60 | |
| 61 | None |
| 62 | |
| 63 | Additions to Chapter 6 of the 1.4 GL Specification (State and State Requests) |
| 64 | |
| 65 | None |
| 66 | |
| 67 | Additions to the GLX 1.3 Specification |
| 68 | |
| 69 | [Add the following to Section 3.3.10 of the GLX Specification (Double |
| 70 | Buffering)] |
| 71 | |
| 72 | glXSwapIntervalMESA specifies the minimum number of video frame periods |
| 73 | per buffer swap. (e.g. a value of two means that the color buffers |
| 74 | will be swapped at most every other video frame.) A return value |
| 75 | of zero indicates success; otherwise an error occurred. The interval |
| 76 | takes effect when glXSwapBuffers is first called subsequent to the |
| 77 | glXSwapIntervalMESA call. |
| 78 | |
| 79 | A video frame period is the time required by the monitor to display a |
| 80 | full frame of video data. In the case of an interlaced monitor, |
| 81 | this is typically the time required to display both the even and odd |
| 82 | fields of a frame of video data. |
| 83 | |
| 84 | If <interval> is set to a value of 0, buffer swaps are not synchron- |
| 85 | ized to a video frame. The <interval> value is silently clamped to |
| 86 | the maximum implementation-dependent value supported before being |
| 87 | stored. |
| 88 | |
| 89 | The swap interval is not part of the render context state. It cannot |
| 90 | be pushed or popped. The current swap interval for the window |
| 91 | associated with the current context can be obtained by calling |
| 92 | glXGetSwapIntervalMESA. The default swap interval is 1. |
| 93 | |
| 94 | On XFree86, setting the environment variable LIBGL_NO_VSYNC sets the |
| 95 | swap interval to 0. |
| 96 | |
| 97 | Errors |
| 98 | |
| 99 | glXSwapIntervalMESA returns GLX_BAD_VALUE if parameter <interval> is |
| 100 | less than zero. |
| 101 | |
| 102 | glXSwapIntervalMESA returns GLX_BAD_CONTEXT if there is no current |
| 103 | GLXContext. |
| 104 | |
| 105 | GLX Protocol |
| 106 | |
| 107 | None. This extension only extends to direct rendering contexts. |
| 108 | |
| 109 | New State |
| 110 | |
| 111 | Get Value Get Command Type Initial Value |
| 112 | --------- ----------- ---- ------------- |
| 113 | [swap interval] GetSwapInterval Z+ 1 |
| 114 | |
| 115 | New Implementation Dependent State |
| 116 | |
| 117 | None |