Add interfaces for overriding texture images with driver specific 'offsets'.

To be used by AIGLX for GLX_EXT_texture_from_pixmap without several
additional data copies.

include/GL/internal/dri_interface.h

@@ -361,6 +361,18 @@ struct __DRIscreenRec {
     void * (*createNewContext)(__DRInativeDisplay *dpy, const __GLcontextModes *modes,
 			       int render_type,
 			       void *sharedPrivate, __DRIcontext *pctx);
+
+    /**
+     * Method to override base texture image with a driver specific 'offset'.
+     * The depth passed in allows e.g. to ignore the alpha channel of texture
+     * images where the non-alpha components don't occupy a whole texel.
+     *
+     * For GLX_EXT_texture_from_pixmap with AIGLX.
+     *
+     * \since Internal API version 20070121.
+     */
+    void (*setTexOffset)(__DRIcontext *pDRICtx, GLint texname,
+			 unsigned long long offset, GLint depth, GLuint pitch);
 };
 
 /**

src/mesa/drivers/dri/common/dri_util.c

@@ -995,6 +995,9 @@ __driUtilCreateNewScreen(__DRInativeDisplay *dpy, int scrn, __DRIscreen *psc,
     psc->getMSC            = driGetMSC;
     psc->createNewContext  = driCreateNewContext;
 
+    if (internal_api_version >= 20070121)
+	psc->setTexOffset  = psp->DriverAPI.setTexOffset;
+
     if ( (psp->DriverAPI.InitDriver != NULL)
 	 && !(*psp->DriverAPI.InitDriver)(psp) ) {
 	_mesa_free( psp );

src/mesa/drivers/dri/common/dri_util.h

@@ -189,6 +189,12 @@ struct __DriverAPIRec {
     /*@}*/
     void (*CopySubBuffer)(__DRIdrawablePrivate *driDrawPriv,
 			  int x, int y, int w, int h);
+
+    /**
+     * See corresponding field in \c __DRIscreenRec.
+     */
+    void (*setTexOffset)(__DRIcontext *pDRICtx, GLint texname,
+			 unsigned long long offset, GLint depth, GLuint pitch);
 };