From 3e07e16ac7ae5035e78df74240eab346b823694c Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Tue, 20 Jul 1999 00:30:41 +0000 Subject: initial rev --- docs/MESA_window_pos.spec | 114 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 docs/MESA_window_pos.spec (limited to 'docs/MESA_window_pos.spec') diff --git a/docs/MESA_window_pos.spec b/docs/MESA_window_pos.spec new file mode 100644 index 0000000000..427bb0eeb5 --- /dev/null +++ b/docs/MESA_window_pos.spec @@ -0,0 +1,114 @@ +Name + + MESA_window_pos + +Name Strings + + GL_MESA_window_pos + +Contact + + Brian Paul, brianp 'at' mesa3d.org + +Status + + Shipping (since Mesa version 1.2.8) + +Version + + $Id: MESA_window_pos.spec,v 1.1 1999/07/20 00:30:41 brianp Exp $ + +Number + + XXX non assigned + +Dependencies + + OpenGL 1.0 is required. + The extension is written against the OpenGL 1.2 Specification + +Overview + + In order to set the current raster position to a specific window + coordinate with the RasterPos command, the modelview matrix, projection + matrix and viewport must be set very carefully. Furthermore, if the + desired window coordinate is outside of the window's bounds one must + rely a subtle side-effect of the Bitmap command in order to circumvent + frustum clipping. + + This extension provides a set of functions to directly set the + current raster position, bypassing the modelview matrix, the + projection matrix and the viewport to window mapping. Furthermore, + clip testing is not performed. + + This greatly simplifies the process of setting the current raster + position to a specific window coordinate prior to calling DrawPixels, + CopyPixels or Bitmap. + +New Procedures and Functions + + void WindowPos2dMESA(double x, double y) + void WindowPos2fMESA(float x, float y) + void WindowPos2iMESA(int x, int y) + void WindowPos2sMESA(short x, short y) + +New Tokens + + none + +Additions to Chapter 2 of the OpenGL 1.2 Specification (OpenGL Operation) + + - (2.12, p. 41) Insert after third paragraph: + + Alternately, the current raster position may be set by one of the + WindowPosMESA commands: + + void WindowPos{234}{sidf}MESA( T coords ); + void Window Pos{234}{sidf}vMESA( T coords ); + + WindosPos4MESA takes four values indicating x, y, z, and w. + WindowPos3MESA (or WindowPos2MESA) is analaguos, but sets only + x, y, and z with w implicitly set to 1 (or only x and y with z + implicititly set to 0 and w implicitly set to 1). + + WindowPosMESA operates like RasterPos except that the current modelview + matrix, projection matrix and viewport parameters are ignored and the + clip test operation always passes. The current raster position values + are directly set to the parameters passed to WindowPosMESA. The current + color, color index and texture coordinate update the current raster + position's associated data. + + The current raster distance ??? XXX ??? + + + + + + + +Additions to the AGL/GLX/WGL Specifications + + None + +GLX Protocol + + Not specified at this time. However, a protocol message very similar + to that of RasterPos is expected. + +Errors + + INVALID_OPERATION is generated if WindowPosMESA is called betweeen + Begin and End. + + +New State + + None. + +New Implementation Dependent State + + None. + +Revision History + + * Revision 1.0 - Initial specification -- cgit v1.2.3