Implement GLX_EXT_texture_from_pixmap.

Could be done more efficiently... but works.

5 files changed, 454 insertions, 25 deletions

diff --git a/src/mesa/drivers/x11/fakeglx.c b/src/mesa/drivers/x11/fakeglx.c
index 86a4deabc67..ef22a3f03eb 100644
--- a/src/mesa/drivers/x11/fakeglx.c
+++ b/src/mesa/drivers/x11/fakeglx.c
@@ -1,8 +1,8 @@
 /*
  * Mesa 3-D graphics library
- * Version:  6.5.2
+ * Version:  7.1
  *
- * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -78,6 +78,7 @@
    "GLX_MESA_pixmap_colormap " \
    "GLX_MESA_release_buffers " \
    "GLX_ARB_get_proc_address " \
+   "GLX_EXT_texture_from_pixmap " \
    "GLX_EXT_visual_info " \
    "GLX_EXT_visual_rating " \
    /*"GLX_SGI_video_sync "*/ \
@@ -1223,6 +1224,30 @@ choose_visual( Display *dpy, int screen, const int *list, GLboolean fbConfig )
             /* ignore */
             break;
 
+#ifdef GLX_EXT_texture_from_pixmap
+         case GLX_BIND_TO_TEXTURE_RGB_EXT:
+            parselist++; /*skip*/
+            break;
+         case GLX_BIND_TO_TEXTURE_RGBA_EXT:
+            parselist++; /*skip*/
+            break;
+         case GLX_BIND_TO_MIPMAP_TEXTURE_EXT:
+            parselist++; /*skip*/
+            break;
+         case GLX_BIND_TO_TEXTURE_TARGETS_EXT:
+            parselist++;
+            if (*parselist & ~(GLX_TEXTURE_1D_BIT_EXT |
+                               GLX_TEXTURE_2D_BIT_EXT |
+                               GLX_TEXTURE_RECTANGLE_BIT_EXT)) {
+               /* invalid bit */
+               return NULL;
+            }
+            break;
+         case GLX_Y_INVERTED_EXT:
+            parselist++; /*skip*/
+            break;
+#endif
+
 	 case None:
             /* end of list */
 	    break;
@@ -1878,6 +1903,27 @@ get_config( XMesaVisual xmvis, int attrib, int *value, GLboolean fbconfig )
          *value = xmvis->visinfo->visualid;
          break;
 
+#ifdef GLX_EXT_texture_from_pixmap
+      case GLX_BIND_TO_TEXTURE_RGB_EXT:
+         *value = True; /*XXX*/
+         break;
+      case GLX_BIND_TO_TEXTURE_RGBA_EXT:
+         /* XXX review */
+         *value = xmvis->mesa_visual.alphaBits > 0 ? True : False;
+         break;
+      case GLX_BIND_TO_MIPMAP_TEXTURE_EXT:
+         *value = True; /*XXX*/
+         break;
+      case GLX_BIND_TO_TEXTURE_TARGETS_EXT:
+         *value = (GLX_TEXTURE_1D_BIT_EXT |
+                   GLX_TEXTURE_2D_BIT_EXT |
+                   GLX_TEXTURE_RECTANGLE_BIT_EXT); /*XXX*/
+         break;
+      case GLX_Y_INVERTED_EXT:
+         *value = False; /*XXX*/
+         break;
+#endif
+
       default:
 	 return GLX_BAD_ATTRIBUTE;
    }
@@ -2145,16 +2191,102 @@ Fake_glXCreatePixmap( Display *dpy, GLXFBConfig config, Pixmap pixmap,
 {
    XMesaVisual v = (XMesaVisual) config;
    XMesaBuffer b;
-
-   (void) dpy;
-   (void) config;
-   (void) pixmap;
-   (void) attribList;  /* Ignored in GLX 1.3 */
+   const int *attr;
+   int target = 0, format = 0, mipmap = 0;
+   int value;
 
    if (!dpy || !config || !pixmap)
       return 0;
 
-   b = XMesaCreatePixmapBuffer( v, pixmap, 0 );
+   for (attr = attribList; *attr; attr++) {
+      switch (*attr) {
+      case GLX_TEXTURE_FORMAT_EXT:
+         attr++;
+         switch (*attr) {
+         case GLX_TEXTURE_FORMAT_NONE_EXT:
+         case GLX_TEXTURE_FORMAT_RGB_EXT:
+         case GLX_TEXTURE_FORMAT_RGBA_EXT:
+            format = *attr;
+            break;
+         default:
+            /* error */
+            return 0;
+         }
+         break;
+      case GLX_TEXTURE_TARGET_EXT:
+         attr++;
+         switch (*attr) {
+         case GLX_TEXTURE_1D_EXT:
+         case GLX_TEXTURE_2D_EXT:
+         case GLX_TEXTURE_RECTANGLE_EXT:
+            target = *attr;
+            break;
+         default:
+            /* error */
+            return 0;
+         }
+         break;
+      case GLX_MIPMAP_TEXTURE_EXT:
+         attr++;
+         if (*attr)
+            mipmap = 1;
+         break;
+      default:
+         /* error */
+         return 0;
+      }
+   }
+
+   if (format == GLX_TEXTURE_FORMAT_RGB_EXT) {
+      if (get_config(v, GLX_BIND_TO_TEXTURE_RGB_EXT,
+                     &value, GL_TRUE) != Success
+          || !value) {
+         return 0; /* error! */
+      }
+   }
+   else if (format == GLX_TEXTURE_FORMAT_RGBA_EXT) {
+      if (get_config(v, GLX_BIND_TO_TEXTURE_RGBA_EXT,
+                     &value, GL_TRUE) != Success
+          || !value) {
+         return 0; /* error! */
+      }
+   }
+   if (mipmap) {
+      if (get_config(v, GLX_BIND_TO_MIPMAP_TEXTURE_EXT,
+                     &value, GL_TRUE) != Success
+          || !value) {
+         return 0; /* error! */
+      }
+   }
+   if (target == GLX_TEXTURE_1D_EXT) {
+      if (get_config(v, GLX_BIND_TO_TEXTURE_TARGETS_EXT,
+                     &value, GL_TRUE) != Success
+          || (value & GLX_TEXTURE_1D_BIT_EXT) == 0) {
+         return 0; /* error! */
+      }
+   }
+   else if (target == GLX_TEXTURE_2D_EXT) {
+      if (get_config(v, GLX_BIND_TO_TEXTURE_TARGETS_EXT,
+                     &value, GL_TRUE) != Success
+          || (value & GLX_TEXTURE_2D_BIT_EXT) == 0) {
+         return 0; /* error! */
+      }
+   }
+   if (target == GLX_TEXTURE_RECTANGLE_EXT) {
+      if (get_config(v, GLX_BIND_TO_TEXTURE_TARGETS_EXT,
+                     &value, GL_TRUE) != Success
+          || (value & GLX_TEXTURE_RECTANGLE_BIT_EXT) == 0) {
+         return 0; /* error! */
+      }
+   }
+
+   if (format || target || mipmap) {
+      /* texture from pixmap */
+      b = XMesaCreatePixmapTextureBuffer(v, pixmap, 0, format, target, mipmap);
+   }
+   else {
+      b = XMesaCreatePixmapBuffer( v, pixmap, 0 );
+   }
    if (!b) {
       return 0;
    }
@@ -2260,8 +2392,20 @@ Fake_glXQueryDrawable( Display *dpy, GLXDrawable draw, int attribute,
       case GLX_FBCONFIG_ID:
          *value = xmbuf->xm_visual->visinfo->visualid;
          return;
+#ifdef GLX_EXT_texture_from_pixmap
+      case GLX_TEXTURE_FORMAT_EXT:
+         *value = xmbuf->TextureFormat;
+         break;
+      case GLX_TEXTURE_TARGET_EXT:
+         *value = xmbuf->TextureTarget;
+         break;
+      case GLX_MIPMAP_TEXTURE_EXT:
+         *value = xmbuf->TextureMipmap;
+         break;
+#endif
+
       default:
-         return;  /* GLX_BAD_ATTRIBUTE? */
+         return; /* raise BadValue error */
    }
 }
 
@@ -2854,6 +2998,26 @@ Fake_glXGetAGPOffsetMESA( const GLvoid *pointer )
 }
 
 
+/*** GLX_EXT_texture_from_pixmap ***/
+
+static void
+Fake_glXBindTexImageEXT(Display *dpy, GLXDrawable drawable, int buffer,
+                        const int *attrib_list)
+{
+   XMesaBuffer b = XMesaFindBuffer(dpy, drawable);
+   if (b)
+      XMesaBindTexImage(dpy, b, buffer, attrib_list);
+}
+
+static void
+Fake_glXReleaseTexImageEXT(Display *dpy, GLXDrawable drawable, int buffer)
+{
+   XMesaBuffer b = XMesaFindBuffer(dpy, drawable);
+   if (b)
+      XMesaReleaseTexImage(dpy, b, buffer);
+}
+
+
 /* silence warning */
 extern struct _glxapi_table *_mesa_GetGLXDispatchTable(void);
 
@@ -3009,5 +3173,9 @@ _mesa_GetGLXDispatchTable(void)
    /*** GLX_MESA_agp_offset ***/
    glx.GetAGPOffsetMESA = Fake_glXGetAGPOffsetMESA;
 
+   /*** GLX_EXT_texture_from_pixmap ***/
+   glx.BindTexImageEXT = Fake_glXBindTexImageEXT;
+   glx.ReleaseTexImageEXT = Fake_glXReleaseTexImageEXT;
+
    return &glx;
 }
diff --git a/src/mesa/drivers/x11/glxapi.c b/src/mesa/drivers/x11/glxapi.c
index 973f3940451..5f11c90c13c 100644
--- a/src/mesa/drivers/x11/glxapi.c
+++ b/src/mesa/drivers/x11/glxapi.c
@@ -1,8 +1,8 @@
 /*
  * Mesa 3-D graphics library
- * Version:  6.5
+ * Version:  7.1
  * 
- * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -1104,6 +1104,27 @@ glXGetMemoryOffsetMESA(Display *dpy, int scrn, const void *pointer)
 }
 
 
+/*** GLX_EXT_texture_from_pixmap */
+
+void
+glXBindTexImageEXT(Display *dpy, GLXDrawable drawable, int buffer,
+                   const int *attrib_list)
+{
+   struct _glxapi_table *t;
+   GET_DISPATCH(dpy, t);
+   if (t)
+      t->BindTexImageEXT(dpy, drawable, buffer, attrib_list);
+}
+
+void
+glXReleaseTexImageEXT(Display *dpy, GLXDrawable drawable, int buffer)
+{
+   struct _glxapi_table *t;
+   GET_DISPATCH(dpy, t);
+   if (t)
+      t->ReleaseTexImageEXT(dpy, drawable, buffer);
+}
+
 
 /**********************************************************************/
 /* GLX API management functions                                       */
@@ -1148,6 +1169,9 @@ _glxapi_get_extensions(void)
 #ifdef GLX_SGIX_pbuffer
       "GLX_SGIX_pbuffer",
 #endif
+#ifdef GLX_EXT_texture_from_pixmap,
+      "GLX_EXT_texture_from_pixmap",
+#endif
       NULL
    };
    return extensions;
@@ -1333,6 +1357,10 @@ static struct name_address_pair GLX_functions[] = {
    { "glXFreeMemoryMESA", (__GLXextFuncPtr) glXFreeMemoryMESA },
    { "glXGetMemoryOffsetMESA", (__GLXextFuncPtr) glXGetMemoryOffsetMESA },
 
+   /*** GLX_EXT_texture_from_pixmap ***/
+   { "glXBindTexImageEXT", (__GLXextFuncPtr) glXBindTexImageEXT },
+   { "glXReleaseTexImageEXT", (__GLXextFuncPtr) glXReleaseTexImageEXT },
+
    { NULL, NULL }   /* end of list */
 };
 
diff --git a/src/mesa/drivers/x11/glxapi.h b/src/mesa/drivers/x11/glxapi.h
index 3187534c9a3..37de81e55ac 100644
--- a/src/mesa/drivers/x11/glxapi.h
+++ b/src/mesa/drivers/x11/glxapi.h
@@ -196,6 +196,11 @@ struct _glxapi_table {
 
    /*** GLX_MESA_agp_offset ***/
    GLuint (*GetAGPOffsetMESA)( const GLvoid *pointer );
+
+   /*** GLX_EXT_texture_from_pixmap ***/
+   void (*BindTexImageEXT)(Display *dpy, GLXDrawable drawable, int buffer,
+                           const int *attrib_list);
+   void (*ReleaseTexImageEXT)(Display *dpy, GLXDrawable drawable, int buffer);
 };
 
 
diff --git a/src/mesa/drivers/x11/xm_api.c b/src/mesa/drivers/x11/xm_api.c
index a07d0a90cf3..edaa71508fc 100644
--- a/src/mesa/drivers/x11/xm_api.c
+++ b/src/mesa/drivers/x11/xm_api.c
@@ -1,8 +1,8 @@
 /*
  * Mesa 3-D graphics library
- * Version:  6.5.2
+ * Version:  7.1
  *
- * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -72,6 +72,7 @@
 #include "imports.h"
 #include "macros.h"
 #include "renderbuffer.h"
+#include "teximage.h"
 #include "swrast/swrast.h"
 #include "swrast_setup/swrast_setup.h"
 #include "vbo/vbo.h"
@@ -295,6 +296,19 @@ static GLboolean window_exists( XMesaDisplay *dpy, Window win )
 #endif
 
 
+static Status
+get_drawable_size(Display *dpy, Drawable d, GLuint *width, GLuint *height)
+{
+   Window root;
+   Status stat;
+   int xpos, ypos;
+   unsigned int w, h, bw, depth;
+   stat = XGetGeometry(dpy, d, &root, &xpos, &ypos, &w, &h, &bw, &depth);
+   *width = w;
+   *height = h;
+   return stat;
+}
+
 
 /**
  * Return the size of the window (or pixmap) that corresponds to the
@@ -310,22 +324,14 @@ xmesa_get_window_size(XMesaDisplay *dpy, XMesaBuffer b,
    *width = MIN2(b->frontxrb->drawable->width, MAX_WIDTH);
    *height = MIN2(b->frontxrb->drawable->height, MAX_HEIGHT);
 #else
-   Window root;
    Status stat;
-   int xpos, ypos;
-   unsigned int w, h, bw, depth;
 
    _glthread_LOCK_MUTEX(_xmesa_lock);
    XSync(b->xm_visual->display, 0); /* added for Chromium */
-   stat = XGetGeometry(dpy, b->frontxrb->pixmap, &root, &xpos, &ypos,
-                       &w, &h, &bw, &depth);
+   stat = get_drawable_size(dpy, b->frontxrb->pixmap, width, height);
    _glthread_UNLOCK_MUTEX(_xmesa_lock);
 
-   if (stat) {
-      *width = w;
-      *height = h;
-   }
-   else {
+   if (!stat) {
       /* probably querying a window that's recently been destroyed */
       _mesa_warning(NULL, "XGetGeometry failed!\n");
       *width = *height = 1;
@@ -431,6 +437,11 @@ create_xmesa_buffer(XMesaDrawable d, BufferType type,
                                 b->swAlpha,
                                 vis->mesa_visual.numAuxBuffers > 0 );
 
+   /* GLX_EXT_texture_from_pixmap */
+   b->TextureTarget = 0;
+   b->TextureFormat = GLX_TEXTURE_FORMAT_NONE_EXT;
+   b->TextureMipmap = 0;
+
    /* insert buffer into linked list */
    b->Next = XMesaBufferList;
    XMesaBufferList = b;
@@ -1673,6 +1684,67 @@ XMesaCreatePixmapBuffer(XMesaVisual v, XMesaPixmap p, XMesaColormap cmap)
 }
 
 
+/**
+ * For GLX_EXT_texture_from_pixmap
+ */
+XMesaBuffer
+XMesaCreatePixmapTextureBuffer(XMesaVisual v, XMesaPixmap p,
+                               XMesaColormap cmap,
+                               int format, int target, int mipmap)
+{
+   GET_CURRENT_CONTEXT(ctx);
+   XMesaBuffer b;
+   GLuint width, height;
+
+   assert(v);
+
+   b = create_xmesa_buffer((XMesaDrawable) p, PIXMAP, v, cmap);
+   if (!b)
+      return NULL;
+
+   /* get pixmap size, update framebuffer/renderbuffer dims */
+   get_drawable_size(v->display, p, &width, &height);
+   _mesa_resize_framebuffer(NULL, &(b->mesa_buffer), width, height);
+
+   if (target == 0) {
+      /* examine dims */
+      if (ctx->Extensions.ARB_texture_non_power_of_two) {
+         target = GLX_TEXTURE_2D_EXT;
+      }
+      else if (   _mesa_bitcount(width)  == 1
+               && _mesa_bitcount(height) == 1) {
+         /* power of two size */
+         if (height == 1) {
+            target = GLX_TEXTURE_1D_EXT;
+         }
+         else {
+            target = GLX_TEXTURE_2D_EXT;
+         }
+      }
+      else if (ctx->Extensions.NV_texture_rectangle) {
+         target = GLX_TEXTURE_RECTANGLE_EXT;
+      }
+      else {
+         /* non power of two textures not supported */
+         XMesaDestroyBuffer(b);
+         return 0;
+      }
+   }
+
+   b->TextureTarget = target;
+   b->TextureFormat = format;
+   b->TextureMipmap = mipmap;
+
+   if (!initialize_visual_and_buffer(v, b, v->mesa_visual.rgbMode,
+				     (XMesaDrawable) p, cmap)) {
+      xmesa_free_buffer(b);
+      return NULL;
+   }
+
+   return b;
+}
+
+
 
 XMesaBuffer
 XMesaCreatePBuffer(XMesaVisual v, XMesaColormap cmap,
@@ -2254,3 +2326,154 @@ XMesaResizeBuffers( XMesaBuffer b )
    xmesa_check_and_update_buffer_size(xmctx, b);
 }
 
+
+static GLint
+xbuffer_to_renderbuffer(int buffer)
+{
+   assert(MAX_AUX_BUFFERS <= 4);
+
+   switch (buffer) {
+   case GLX_FRONT_LEFT_EXT:
+      return BUFFER_FRONT_LEFT;
+   case GLX_FRONT_RIGHT_EXT:
+      return BUFFER_FRONT_RIGHT;
+   case GLX_BACK_LEFT_EXT:
+      return BUFFER_BACK_LEFT;
+   case GLX_BACK_RIGHT_EXT:
+      return BUFFER_BACK_RIGHT;
+   case GLX_AUX0_EXT:
+      return BUFFER_AUX0;
+   case GLX_AUX1_EXT:
+      return BUFFER_AUX1;
+   case GLX_AUX2_EXT:
+      return BUFFER_AUX2;
+   case GLX_AUX3_EXT:
+      return BUFFER_AUX3;
+   case GLX_AUX4_EXT:
+   case GLX_AUX5_EXT:
+   case GLX_AUX6_EXT:
+   case GLX_AUX7_EXT:
+   case GLX_AUX8_EXT:
+   case GLX_AUX9_EXT:
+   default:
+      /* BadValue error */
+      return -1;
+   }
+}
+
+
+PUBLIC void
+XMesaBindTexImage(Display *dpy, XMesaBuffer drawable, int buffer,
+                  const int *attrib_list)
+{
+#if 0
+   GET_CURRENT_CONTEXT(ctx);
+   const GLuint unit = ctx->Texture.CurrentUnit;
+   struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
+   struct gl_texture_object *texObj;
+#endif
+   struct gl_renderbuffer *rb;
+   struct xmesa_renderbuffer *xrb;
+   GLint b;
+   XMesaImage *img;
+   GLboolean freeImg = GL_FALSE;
+
+   b = xbuffer_to_renderbuffer(buffer);
+   if (b < 0)
+      return;
+
+   if (drawable->TextureFormat == GLX_TEXTURE_FORMAT_NONE_EXT)
+      return; /* BadMatch error */
+
+   rb = drawable->mesa_buffer.Attachment[b].Renderbuffer;
+   if (!rb) {
+      /* invalid buffer */
+      return;
+   }
+   xrb = xmesa_renderbuffer(rb);
+
+#if 0
+   switch (drawable->TextureTarget) {
+   case GLX_TEXTURE_1D_EXT:
+      texObj = texUnit->Current1D;
+      break;
+   case GLX_TEXTURE_2D_EXT:
+      texObj = texUnit->Current2D;
+      break;
+   case GLX_TEXTURE_RECTANGLE_EXT:
+      texObj = texUnit->CurrentRect;
+      break;
+   default:
+      return; /* BadMatch error */
+   }
+#endif
+
+   /*
+    * The following is a quick and simple way to implement
+    * BindTexImage.  The better way is to write some new FetchTexel()
+    * functions which would extract texels from XImages.  We'd still
+    * need to use XGetImage when texturing from a Pixmap (front buffer)
+    * but texturing from a back buffer (XImage) would avoid an image
+    * copy.
+    */
+
+   /* get XImage */
+   if (xrb->pixmap) {
+      img = XGetImage(dpy, xrb->pixmap, 0, 0, rb->Width, rb->Height,
+                      AllPlanes, ZPixmap );
+      freeImg = GL_TRUE;
+   }
+   else if (xrb->ximage) {
+      img = xrb->ximage;
+   }
+
+   /* store the XImage as a new texture image */
+   if (img) {
+      GLenum format, type, intFormat;
+      if (img->bits_per_pixel == 32) {
+         format = GL_BGRA;
+         type = GL_UNSIGNED_BYTE;
+         intFormat = GL_RGBA;
+      }
+      else if (img->bits_per_pixel == 24) {
+         format = GL_BGR;
+         type = GL_UNSIGNED_BYTE;
+         intFormat = GL_RGB;
+      }
+      else if (img->bits_per_pixel == 16) {
+         format = GL_BGR;
+         type = GL_UNSIGNED_SHORT_5_6_5;
+         intFormat = GL_RGB;
+      }
+      else {
+         _mesa_problem(NULL, "Unexpected XImage format in XMesaBindTexImage");
+         return;
+      }
+      if (drawable->TextureFormat == GLX_TEXTURE_FORMAT_RGBA_EXT) {
+         intFormat = GL_RGBA;
+      }
+      else if (drawable->TextureFormat == GLX_TEXTURE_FORMAT_RGB_EXT) {
+         intFormat = GL_RGB;
+      }
+
+      _mesa_TexImage2D(GL_TEXTURE_2D, 0, intFormat, rb->Width, rb->Height, 0,
+                       format, type, img->data);
+
+      if (freeImg) {
+	 XMesaDestroyImage(img);
+      }
+   }
+}
+
+
+
+PUBLIC void
+XMesaReleaseTexImage(Display *dpy, XMesaBuffer drawable, int buffer)
+{
+   const GLint b = xbuffer_to_renderbuffer(buffer);
+   if (b < 0)
+      return;
+
+   /* no-op for now */
+}
+
diff --git a/src/mesa/drivers/x11/xmesaP.h b/src/mesa/drivers/x11/xmesaP.h
index 01988867476..e3d7cf381f7 100644
--- a/src/mesa/drivers/x11/xmesaP.h
+++ b/src/mesa/drivers/x11/xmesaP.h
@@ -1,8 +1,8 @@
 /*
  * Mesa 3-D graphics library
- * Version:  6.5
+ * Version:  7.1
  *
- * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -267,6 +267,11 @@ struct xmesa_buffer {
    fxMesaContext FXctx;
 #endif
 
+   /* GLX_EXT_texture_from_pixmap */
+   GLint TextureTarget; /** GLX_TEXTURE_1D_EXT, for example */
+   GLint TextureFormat; /** GLX_TEXTURE_FORMAT_RGB_EXT, for example */
+   GLint TextureMipmap; /** 0 or 1 */
+
    struct xmesa_buffer *Next;	/* Linked list pointer: */
 };