Split driver struct into swrast/tnl/core components.

4 files changed, 209 insertions, 186 deletions

diff --git a/src/mesa/drivers/x11/xm_api.c b/src/mesa/drivers/x11/xm_api.c
index abbec2d7dd..96dfc4bfe4 100644
--- a/src/mesa/drivers/x11/xm_api.c
+++ b/src/mesa/drivers/x11/xm_api.c
@@ -1,4 +1,4 @@
-/* $Id: xm_api.c,v 1.18 2001/03/08 15:23:46 brianp Exp $ */
+/* $Id: xm_api.c,v 1.19 2001/03/19 02:25:36 keithw Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -1659,10 +1659,6 @@ XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
    c->driContextPriv = driContextPriv;
 #endif
 
-   /* Set up some constant pointers:
-    */
-   xmesa_init_pointers( ctx );
-
    /* Initialize the software rasterizer and helper modules.
     */
    _swrast_CreateContext( ctx );
@@ -1672,6 +1668,11 @@ XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
 
    xmesa_register_swrast_functions( ctx );
 
+   /* Set up some constant pointers:
+    */
+   xmesa_init_pointers( ctx );
+
+
    /* Run the config file
     */
    _mesa_context_initialize( ctx );
@@ -1692,6 +1693,8 @@ void XMesaDestroyContext( XMesaContext c )
    if (c->gl_ctx) {
       _swsetup_DestroyContext( c->gl_ctx );
       _swrast_DestroyContext( c->gl_ctx );
+      _tnl_DestroyContext( c->gl_ctx );
+      _ac_DestroyContext( c->gl_ctx );
       _mesa_destroy_context( c->gl_ctx );
    }
 
diff --git a/src/mesa/drivers/x11/xm_dd.c b/src/mesa/drivers/x11/xm_dd.c
index a73b3c6973..2bb04ae504 100644
--- a/src/mesa/drivers/x11/xm_dd.c
+++ b/src/mesa/drivers/x11/xm_dd.c
@@ -1,4 +1,4 @@
-/* $Id: xm_dd.c,v 1.18 2001/03/03 20:33:30 brianp Exp $ */
+/* $Id: xm_dd.c,v 1.19 2001/03/19 02:25:36 keithw Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -41,6 +41,7 @@
 #include "swrast/s_alphabuf.h"
 #include "swrast_setup/swrast_setup.h"
 #include "tnl/tnl.h"
+#include "tnl/t_context.h"
 
 
 /*
@@ -181,8 +182,8 @@ set_draw_buffer( GLcontext *ctx, GLenum mode )
 }
 
 
-static void
-set_read_buffer( GLcontext *ctx, GLframebuffer *buffer, GLenum mode )
+void
+xmesa_set_read_buffer( GLcontext *ctx, GLframebuffer *buffer, GLenum mode )
 {
    XMesaBuffer target;
    const XMesaContext xmesa = (XMesaContext) ctx->DriverCtx;
@@ -933,27 +934,13 @@ void xmesa_update_state( GLcontext *ctx, GLuint new_state )
  */
 void xmesa_init_pointers( GLcontext *ctx )
 {
+   TNLcontext *tnl;
+
    ctx->Driver.GetString = get_string;
    ctx->Driver.GetBufferSize = get_buffer_size;
    ctx->Driver.Flush = flush;
    ctx->Driver.Finish = finish;
- 
-   /* Hooks for t_vb_render.c:
-    */
-   ctx->Driver.RenderStart = _swsetup_RenderStart;
-   ctx->Driver.RenderFinish = _swsetup_RenderFinish;
-   ctx->Driver.BuildProjectedVertices = _swsetup_BuildProjectedVertices;
-   ctx->Driver.RenderPrimitive = _swsetup_RenderPrimitive;
-   ctx->Driver.PointsFunc = _swsetup_Points;
-   ctx->Driver.LineFunc = _swsetup_Line;
-   ctx->Driver.TriangleFunc = _swsetup_Triangle;
-   ctx->Driver.QuadFunc = _swsetup_Quad;
-   ctx->Driver.ResetLineStipple = _swrast_ResetLineStipple;
-   ctx->Driver.RenderInterp = _swsetup_RenderInterp;
-   ctx->Driver.RenderCopyPV = _swsetup_RenderCopyPV;
-   ctx->Driver.RenderClippedLine = _swsetup_RenderClippedLine;
-   ctx->Driver.RenderClippedPolygon = _swsetup_RenderClippedPolygon;
-   
+    
    /* Software rasterizer pixel paths:
     */
    ctx->Driver.Accum = _swrast_Accum;
@@ -972,22 +959,49 @@ void xmesa_init_pointers( GLcontext *ctx )
    ctx->Driver.TexSubImage1D = _mesa_store_texsubimage1d;
    ctx->Driver.TexSubImage2D = _mesa_store_texsubimage2d;
    ctx->Driver.TexSubImage3D = _mesa_store_texsubimage3d;
-   ctx->Driver.CopyTexImage1D = _mesa_copy_teximage1d;
-   ctx->Driver.CopyTexImage2D = _mesa_copy_teximage2d;
-   ctx->Driver.CopyTexSubImage1D = _mesa_copy_texsubimage1d;
-   ctx->Driver.CopyTexSubImage2D = _mesa_copy_texsubimage2d;
-   ctx->Driver.CopyTexSubImage3D = _mesa_copy_texsubimage3d;
    ctx->Driver.TestProxyTexImage = _mesa_test_proxy_teximage;
 
-   /* 
+   ctx->Driver.CopyTexImage1D = _swrast_copy_teximage1d;
+   ctx->Driver.CopyTexImage2D = _swrast_copy_teximage2d;
+   ctx->Driver.CopyTexSubImage1D = _swrast_copy_texsubimage1d;
+   ctx->Driver.CopyTexSubImage2D = _swrast_copy_texsubimage2d;
+   ctx->Driver.CopyTexSubImage3D = _swrast_copy_texsubimage3d;
+
+
+   /* Swrast hooks for imaging extensions:
+    */
+   ctx->Driver.CopyColorTable = _swrast_CopyColorTable;
+   ctx->Driver.CopyColorSubTable = _swrast_CopyColorSubTable;
+   ctx->Driver.CopyConvolutionFilter1D = _swrast_CopyConvolutionFilter1D;
+   ctx->Driver.CopyConvolutionFilter2D = _swrast_CopyConvolutionFilter2D;
+
+
+   /* Statechange callbacks:
     */
    ctx->Driver.SetDrawBuffer = set_draw_buffer;
-   ctx->Driver.SetReadBuffer = set_read_buffer;
    ctx->Driver.ClearIndex = clear_index;
    ctx->Driver.ClearColor = clear_color;
    ctx->Driver.IndexMask = index_mask;
    ctx->Driver.ColorMask = color_mask;
    ctx->Driver.Enable = enable;
 
+
+   /* Initialize the TNL driver interface:
+    */
+   tnl = TNL_CONTEXT(ctx);
+   tnl->Driver.RenderStart = _swsetup_RenderStart;
+   tnl->Driver.RenderFinish = _swsetup_RenderFinish;
+   tnl->Driver.BuildProjectedVertices = _swsetup_BuildProjectedVertices;
+   tnl->Driver.RenderPrimitive = _swsetup_RenderPrimitive;
+   tnl->Driver.PointsFunc = _swsetup_Points;
+   tnl->Driver.LineFunc = _swsetup_Line;
+   tnl->Driver.TriangleFunc = _swsetup_Triangle;
+   tnl->Driver.QuadFunc = _swsetup_Quad;
+   tnl->Driver.ResetLineStipple = _swrast_ResetLineStipple;
+   tnl->Driver.RenderInterp = _swsetup_RenderInterp;
+   tnl->Driver.RenderCopyPV = _swsetup_RenderCopyPV;
+   tnl->Driver.RenderClippedLine = _swsetup_RenderClippedLine;
+   tnl->Driver.RenderClippedPolygon = _swsetup_RenderClippedPolygon;
+
    (void) DitherValues;  /* silenced unused var warning */
 }
diff --git a/src/mesa/drivers/x11/xm_span.c b/src/mesa/drivers/x11/xm_span.c
index e87fd98a8a..0991a44f7e 100644
--- a/src/mesa/drivers/x11/xm_span.c
+++ b/src/mesa/drivers/x11/xm_span.c
@@ -1,4 +1,4 @@
-/* $Id: xm_span.c,v 1.10 2001/03/03 20:33:30 brianp Exp $ */
+/* $Id: xm_span.c,v 1.11 2001/03/19 02:25:36 keithw Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -36,7 +36,7 @@
 #include "xmesaP.h"
 #include "extensions.h"
 
-
+#include "swrast/swrast.h"
 
 
 /*
@@ -4236,6 +4236,7 @@ void xmesa_update_span_funcs( GLcontext *ctx )
 {
    XMesaContext xmesa = (XMesaContext) ctx->DriverCtx;
    int depth=GET_VISUAL_DEPTH(xmesa->xm_visual);
+   struct swrast_device_driver *dd = _swrast_GetDeviceDriverReference( ctx );
 
    /*
     * These drawing functions depend on color buffer config:
@@ -4244,98 +4245,98 @@ void xmesa_update_span_funcs( GLcontext *ctx )
       /* Writing to window or back pixmap */
       switch (xmesa->pixelformat) {
 	 case PF_INDEX:
-	    ctx->Driver.WriteCI32Span     = write_span_index_pixmap;
-	    ctx->Driver.WriteCI8Span      = write_span_index8_pixmap;
-	    ctx->Driver.WriteMonoCISpan   = write_span_mono_index_pixmap;
-	    ctx->Driver.WriteCI32Pixels   = write_pixels_index_pixmap;
-	    ctx->Driver.WriteMonoCIPixels = write_pixels_mono_index_pixmap;
+	    dd->WriteCI32Span     = write_span_index_pixmap;
+	    dd->WriteCI8Span      = write_span_index8_pixmap;
+	    dd->WriteMonoCISpan   = write_span_mono_index_pixmap;
+	    dd->WriteCI32Pixels   = write_pixels_index_pixmap;
+	    dd->WriteMonoCIPixels = write_pixels_mono_index_pixmap;
 	    break;
 	 case PF_TRUECOLOR:
-	    ctx->Driver.WriteRGBASpan       = write_span_TRUECOLOR_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_TRUECOLOR_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_TRUECOLOR_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+	    dd->WriteRGBASpan       = write_span_TRUECOLOR_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_TRUECOLOR_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_TRUECOLOR_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
 	    break;
 	 case PF_TRUEDITHER:
-	    ctx->Driver.WriteRGBASpan       = write_span_TRUEDITHER_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_TRUEDITHER_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_TRUEDITHER_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_TRUEDITHER_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_TRUEDITHER_pixmap;
+	    dd->WriteRGBASpan       = write_span_TRUEDITHER_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_TRUEDITHER_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_TRUEDITHER_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_TRUEDITHER_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_TRUEDITHER_pixmap;
 	    break;
 	 case PF_8A8B8G8R:
-	    ctx->Driver.WriteRGBASpan       = write_span_8A8B8G8R_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_8A8B8G8R_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_8A8B8G8R_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+	    dd->WriteRGBASpan       = write_span_8A8B8G8R_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_8A8B8G8R_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_8A8B8G8R_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
 	    break;
 	 case PF_8R8G8B:
-	    ctx->Driver.WriteRGBASpan       = write_span_8R8G8B_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_8R8G8B_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_8R8G8B_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+	    dd->WriteRGBASpan       = write_span_8R8G8B_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_8R8G8B_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_8R8G8B_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
 	    break;
 	 case PF_8R8G8B24:
-	    ctx->Driver.WriteRGBASpan       = write_span_8R8G8B24_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_8R8G8B24_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_8R8G8B24_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+	    dd->WriteRGBASpan       = write_span_8R8G8B24_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_8R8G8B24_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_8R8G8B24_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
 	    break;
 	 case PF_5R6G5B:
-	    ctx->Driver.WriteRGBASpan       = write_span_5R6G5B_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_5R6G5B_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_5R6G5B_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+	    dd->WriteRGBASpan       = write_span_5R6G5B_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_5R6G5B_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_5R6G5B_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
 	    break;
 	 case PF_DITHER_5R6G5B:
-	    ctx->Driver.WriteRGBASpan       = write_span_DITHER_5R6G5B_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_DITHER_5R6G5B_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_TRUEDITHER_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_DITHER_5R6G5B_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_TRUEDITHER_pixmap;
+	    dd->WriteRGBASpan       = write_span_DITHER_5R6G5B_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_DITHER_5R6G5B_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_TRUEDITHER_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_DITHER_5R6G5B_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_TRUEDITHER_pixmap;
 	    break;
 	 case PF_DITHER:
-	    ctx->Driver.WriteRGBASpan       = write_span_DITHER_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_DITHER_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_DITHER_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_DITHER_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_DITHER_pixmap;
+	    dd->WriteRGBASpan       = write_span_DITHER_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_DITHER_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_DITHER_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_DITHER_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_DITHER_pixmap;
 	    break;
 	 case PF_1BIT:
-	    ctx->Driver.WriteRGBASpan       = write_span_1BIT_pixmap;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_1BIT_pixmap;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_1BIT_pixmap;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_1BIT_pixmap;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_1BIT_pixmap;
+	    dd->WriteRGBASpan       = write_span_1BIT_pixmap;
+	    dd->WriteRGBSpan        = write_span_rgb_1BIT_pixmap;
+	    dd->WriteMonoRGBASpan   = write_span_mono_1BIT_pixmap;
+	    dd->WriteRGBAPixels     = write_pixels_1BIT_pixmap;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_1BIT_pixmap;
 	    break;
          case PF_HPCR:
-            ctx->Driver.WriteRGBASpan       = write_span_HPCR_pixmap;
-            ctx->Driver.WriteRGBSpan        = write_span_rgb_HPCR_pixmap;
-            ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-            ctx->Driver.WriteRGBAPixels     = write_pixels_HPCR_pixmap;
-            ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+            dd->WriteRGBASpan       = write_span_HPCR_pixmap;
+            dd->WriteRGBSpan        = write_span_rgb_HPCR_pixmap;
+            dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+            dd->WriteRGBAPixels     = write_pixels_HPCR_pixmap;
+            dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
 	    if (xmesa->xm_visual->hpcr_clear_flag) {
-   		ctx->Driver.ClearColor = clear_color_HPCR_pixmap;
+	       ctx->Driver.ClearColor = clear_color_HPCR_pixmap;
 	    }
             break;
          case PF_LOOKUP:
-            ctx->Driver.WriteRGBASpan       = write_span_LOOKUP_pixmap;
-            ctx->Driver.WriteRGBSpan        = write_span_rgb_LOOKUP_pixmap;
-            ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-            ctx->Driver.WriteRGBAPixels     = write_pixels_LOOKUP_pixmap;
-            ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+            dd->WriteRGBASpan       = write_span_LOOKUP_pixmap;
+            dd->WriteRGBSpan        = write_span_rgb_LOOKUP_pixmap;
+            dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+            dd->WriteRGBAPixels     = write_pixels_LOOKUP_pixmap;
+            dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
             break;
          case PF_GRAYSCALE:
-            ctx->Driver.WriteRGBASpan       = write_span_GRAYSCALE_pixmap;
-            ctx->Driver.WriteRGBSpan        = write_span_rgb_GRAYSCALE_pixmap;
-            ctx->Driver.WriteMonoRGBASpan   = write_span_mono_pixmap;
-            ctx->Driver.WriteRGBAPixels     = write_pixels_GRAYSCALE_pixmap;
-            ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_pixmap;
+            dd->WriteRGBASpan       = write_span_GRAYSCALE_pixmap;
+            dd->WriteRGBSpan        = write_span_rgb_GRAYSCALE_pixmap;
+            dd->WriteMonoRGBASpan   = write_span_mono_pixmap;
+            dd->WriteRGBAPixels     = write_pixels_GRAYSCALE_pixmap;
+            dd->WriteMonoRGBAPixels = write_pixels_mono_pixmap;
             break;
 	 default:
 	    _mesa_problem(NULL,"Bad pixel format in xmesa_update_state (1)");
@@ -4346,128 +4347,128 @@ void xmesa_update_span_funcs( GLcontext *ctx )
       /* Writing to back XImage */
       switch (xmesa->pixelformat) {
 	 case PF_INDEX:
-	    ctx->Driver.WriteCI32Span     = write_span_index_ximage;
+	    dd->WriteCI32Span     = write_span_index_ximage;
 	    if (depth==8)
-               ctx->Driver.WriteCI8Span   = write_span_index8_ximage8;
+               dd->WriteCI8Span   = write_span_index8_ximage8;
             else
-               ctx->Driver.WriteCI8Span   = write_span_index8_ximage;
-	    ctx->Driver.WriteMonoCISpan   = write_span_mono_index_ximage;
-	    ctx->Driver.WriteCI32Pixels   = write_pixels_index_ximage;
-	    ctx->Driver.WriteMonoCIPixels = write_pixels_mono_index_ximage;
+               dd->WriteCI8Span   = write_span_index8_ximage;
+	    dd->WriteMonoCISpan   = write_span_mono_index_ximage;
+	    dd->WriteCI32Pixels   = write_pixels_index_ximage;
+	    dd->WriteMonoCIPixels = write_pixels_mono_index_ximage;
 	    break;
 	 case PF_TRUECOLOR:
 	    /* Generic RGB */
-	    ctx->Driver.WriteRGBASpan       = write_span_TRUECOLOR_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_TRUECOLOR_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_TRUECOLOR_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_ximage;
+	    dd->WriteRGBASpan       = write_span_TRUECOLOR_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_TRUECOLOR_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_TRUECOLOR_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_ximage;
 	    break;
 	 case PF_TRUEDITHER:
-	    ctx->Driver.WriteRGBASpan       = write_span_TRUEDITHER_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_TRUEDITHER_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_TRUEDITHER_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_TRUEDITHER_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_TRUEDITHER_ximage;
+	    dd->WriteRGBASpan       = write_span_TRUEDITHER_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_TRUEDITHER_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_TRUEDITHER_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_TRUEDITHER_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_TRUEDITHER_ximage;
 	    break;
 	 case PF_8A8B8G8R:
-	    ctx->Driver.WriteRGBASpan       = write_span_8A8B8G8R_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_8A8B8G8R_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_8A8B8G8R_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_8A8B8G8R_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_8A8B8G8R_ximage;
+	    dd->WriteRGBASpan       = write_span_8A8B8G8R_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_8A8B8G8R_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_8A8B8G8R_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_8A8B8G8R_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_8A8B8G8R_ximage;
 	    break;
 	 case PF_8R8G8B:
-	    ctx->Driver.WriteRGBASpan       = write_span_8R8G8B_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_8R8G8B_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_8R8G8B_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_8R8G8B_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_8R8G8B_ximage;
+	    dd->WriteRGBASpan       = write_span_8R8G8B_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_8R8G8B_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_8R8G8B_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_8R8G8B_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_8R8G8B_ximage;
 	    break;
 	 case PF_8R8G8B24:
-	    ctx->Driver.WriteRGBASpan       = write_span_8R8G8B24_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_8R8G8B24_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_8R8G8B24_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_8R8G8B24_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_8R8G8B24_ximage;
+	    dd->WriteRGBASpan       = write_span_8R8G8B24_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_8R8G8B24_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_8R8G8B24_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_8R8G8B24_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_8R8G8B24_ximage;
 	    break;
 	 case PF_5R6G5B:
-	    ctx->Driver.WriteRGBASpan       = write_span_5R6G5B_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_5R6G5B_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_5R6G5B_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_ximage;
+	    dd->WriteRGBASpan       = write_span_5R6G5B_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_5R6G5B_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_5R6G5B_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_ximage;
 	    break;
 	 case PF_DITHER_5R6G5B:
-	    ctx->Driver.WriteRGBASpan       = write_span_DITHER_5R6G5B_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_DITHER_5R6G5B_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_DITHER_5R6G5B_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_DITHER_5R6G5B_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_DITHER_5R6G5B_ximage;
+	    dd->WriteRGBASpan       = write_span_DITHER_5R6G5B_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_DITHER_5R6G5B_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_DITHER_5R6G5B_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_DITHER_5R6G5B_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_DITHER_5R6G5B_ximage;
 	    break;
 	 case PF_DITHER:
 	    if (depth==8) {
-	       ctx->Driver.WriteRGBASpan      = write_span_DITHER8_ximage;
-	       ctx->Driver.WriteRGBSpan       = write_span_rgb_DITHER8_ximage;
-	       ctx->Driver.WriteMonoRGBASpan  = write_span_mono_DITHER8_ximage;
-	       ctx->Driver.WriteRGBAPixels    = write_pixels_DITHER8_ximage;
-	       ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_DITHER8_ximage;
+	       dd->WriteRGBASpan      = write_span_DITHER8_ximage;
+	       dd->WriteRGBSpan       = write_span_rgb_DITHER8_ximage;
+	       dd->WriteMonoRGBASpan  = write_span_mono_DITHER8_ximage;
+	       dd->WriteRGBAPixels    = write_pixels_DITHER8_ximage;
+	       dd->WriteMonoRGBAPixels = write_pixels_mono_DITHER8_ximage;
 	    }
 	    else {
-	       ctx->Driver.WriteRGBASpan       = write_span_DITHER_ximage;
-	       ctx->Driver.WriteRGBSpan        = write_span_rgb_DITHER_ximage;
-	       ctx->Driver.WriteMonoRGBASpan   = write_span_mono_DITHER_ximage;
-	       ctx->Driver.WriteRGBAPixels     = write_pixels_DITHER_ximage;
-	       ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_DITHER_ximage;
+	       dd->WriteRGBASpan       = write_span_DITHER_ximage;
+	       dd->WriteRGBSpan        = write_span_rgb_DITHER_ximage;
+	       dd->WriteMonoRGBASpan   = write_span_mono_DITHER_ximage;
+	       dd->WriteRGBAPixels     = write_pixels_DITHER_ximage;
+	       dd->WriteMonoRGBAPixels = write_pixels_mono_DITHER_ximage;
 	    }
 	    break;
 	 case PF_1BIT:
-	    ctx->Driver.WriteRGBASpan       = write_span_1BIT_ximage;
-	    ctx->Driver.WriteRGBSpan        = write_span_rgb_1BIT_ximage;
-	    ctx->Driver.WriteMonoRGBASpan   = write_span_mono_1BIT_ximage;
-	    ctx->Driver.WriteRGBAPixels     = write_pixels_1BIT_ximage;
-	    ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_1BIT_ximage;
+	    dd->WriteRGBASpan       = write_span_1BIT_ximage;
+	    dd->WriteRGBSpan        = write_span_rgb_1BIT_ximage;
+	    dd->WriteMonoRGBASpan   = write_span_mono_1BIT_ximage;
+	    dd->WriteRGBAPixels     = write_pixels_1BIT_ximage;
+	    dd->WriteMonoRGBAPixels = write_pixels_mono_1BIT_ximage;
 	    break;
          case PF_HPCR:
-            ctx->Driver.WriteRGBASpan       = write_span_HPCR_ximage;
-            ctx->Driver.WriteRGBSpan        = write_span_rgb_HPCR_ximage;
-            ctx->Driver.WriteMonoRGBASpan   = write_span_mono_HPCR_ximage;
-            ctx->Driver.WriteRGBAPixels     = write_pixels_HPCR_ximage;
-            ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_HPCR_ximage;
+            dd->WriteRGBASpan       = write_span_HPCR_ximage;
+            dd->WriteRGBSpan        = write_span_rgb_HPCR_ximage;
+            dd->WriteMonoRGBASpan   = write_span_mono_HPCR_ximage;
+            dd->WriteRGBAPixels     = write_pixels_HPCR_ximage;
+            dd->WriteMonoRGBAPixels = write_pixels_mono_HPCR_ximage;
 	    if (xmesa->xm_visual->hpcr_clear_flag) {
                ctx->Driver.ClearColor = clear_color_HPCR_ximage;
 	    }
             break;
          case PF_LOOKUP:
 	    if (depth==8) {
-               ctx->Driver.WriteRGBASpan       = write_span_LOOKUP8_ximage;
-               ctx->Driver.WriteRGBSpan        = write_rgb_LOOKUP8_ximage;
-               ctx->Driver.WriteMonoRGBASpan   = write_span_mono_LOOKUP8_ximage;
-               ctx->Driver.WriteRGBAPixels     = write_pixels_LOOKUP8_ximage;
-               ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_LOOKUP8_ximage;
+               dd->WriteRGBASpan       = write_span_LOOKUP8_ximage;
+               dd->WriteRGBSpan        = write_rgb_LOOKUP8_ximage;
+               dd->WriteMonoRGBASpan   = write_span_mono_LOOKUP8_ximage;
+               dd->WriteRGBAPixels     = write_pixels_LOOKUP8_ximage;
+               dd->WriteMonoRGBAPixels = write_pixels_mono_LOOKUP8_ximage;
             }
             else {
-               ctx->Driver.WriteRGBASpan       = write_span_LOOKUP_ximage;
-               ctx->Driver.WriteRGBSpan        = write_span_rgb_LOOKUP_ximage;
-               ctx->Driver.WriteMonoRGBASpan   = write_span_mono_ximage;
-               ctx->Driver.WriteRGBAPixels     = write_pixels_LOOKUP_ximage;
-               ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_ximage;
+               dd->WriteRGBASpan       = write_span_LOOKUP_ximage;
+               dd->WriteRGBSpan        = write_span_rgb_LOOKUP_ximage;
+               dd->WriteMonoRGBASpan   = write_span_mono_ximage;
+               dd->WriteRGBAPixels     = write_pixels_LOOKUP_ximage;
+               dd->WriteMonoRGBAPixels = write_pixels_mono_ximage;
             }
             break;
          case PF_GRAYSCALE:
 	    if (depth==8) {
-	       ctx->Driver.WriteRGBASpan       = write_span_GRAYSCALE8_ximage;
-	       ctx->Driver.WriteRGBSpan        = write_span_rgb_GRAYSCALE8_ximage;
-	       ctx->Driver.WriteMonoRGBASpan   = write_span_mono_GRAYSCALE8_ximage;
-	       ctx->Driver.WriteRGBAPixels     = write_pixels_GRAYSCALE8_ximage;
-	       ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_GRAYSCALE8_ximage;
+	       dd->WriteRGBASpan       = write_span_GRAYSCALE8_ximage;
+	       dd->WriteRGBSpan        = write_span_rgb_GRAYSCALE8_ximage;
+	       dd->WriteMonoRGBASpan   = write_span_mono_GRAYSCALE8_ximage;
+	       dd->WriteRGBAPixels     = write_pixels_GRAYSCALE8_ximage;
+	       dd->WriteMonoRGBAPixels = write_pixels_mono_GRAYSCALE8_ximage;
 	    }
 	    else {
-	       ctx->Driver.WriteRGBASpan       = write_span_GRAYSCALE_ximage;
-	       ctx->Driver.WriteRGBSpan        = write_span_rgb_GRAYSCALE_ximage;
-	       ctx->Driver.WriteMonoRGBASpan   = write_span_mono_ximage;
-	       ctx->Driver.WriteRGBAPixels     = write_pixels_GRAYSCALE_ximage;
-	       ctx->Driver.WriteMonoRGBAPixels = write_pixels_mono_ximage;
+	       dd->WriteRGBASpan       = write_span_GRAYSCALE_ximage;
+	       dd->WriteRGBSpan        = write_span_rgb_GRAYSCALE_ximage;
+	       dd->WriteMonoRGBASpan   = write_span_mono_ximage;
+	       dd->WriteRGBAPixels     = write_pixels_GRAYSCALE_ximage;
+	       dd->WriteMonoRGBAPixels = write_pixels_mono_ximage;
 	    }
 	    break;
 	 default:
@@ -4477,8 +4478,10 @@ void xmesa_update_span_funcs( GLcontext *ctx )
    }
 
    /* Pixel/span reading functions: */
-   ctx->Driver.ReadCI32Span = read_index_span;
-   ctx->Driver.ReadRGBASpan = read_color_span;
-   ctx->Driver.ReadCI32Pixels = read_index_pixels;
-   ctx->Driver.ReadRGBAPixels = read_color_pixels;
+   dd->ReadCI32Span = read_index_span;
+   dd->ReadRGBASpan = read_color_span;
+   dd->ReadCI32Pixels = read_index_pixels;
+   dd->ReadRGBAPixels = read_color_pixels;
+
+   dd->SetReadBuffer = xmesa_set_read_buffer;
 }
diff --git a/src/mesa/drivers/x11/xmesaP.h b/src/mesa/drivers/x11/xmesaP.h
index 8aa8a47b14..34d07c9e82 100644
--- a/src/mesa/drivers/x11/xmesaP.h
+++ b/src/mesa/drivers/x11/xmesaP.h
@@ -1,4 +1,4 @@
-/* $Id: xmesaP.h,v 1.19 2001/01/08 04:06:20 keithw Exp $ */
+/* $Id: xmesaP.h,v 1.20 2001/03/19 02:25:36 keithw Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -551,4 +551,7 @@ extern GLboolean XMesaForceCurrent(XMesaContext c);
 extern GLboolean XMesaLoseCurrent(XMesaContext c);
 extern void XMesaReset( void );
 
+extern void xmesa_set_read_buffer( GLcontext *ctx, 
+				   GLframebuffer *buffer, GLenum mode );
+
 #endif