Dave Reveman's patch for GLX_MESA_copy_sub_buffer support

20 files changed, 301 insertions, 71 deletions

diff --git a/src/mesa/drivers/dri/common/dri_util.c b/src/mesa/drivers/dri/common/dri_util.c
index 883a89c888..d68837b545 100644
--- a/src/mesa/drivers/dri/common/dri_util.c
+++ b/src/mesa/drivers/dri/common/dri_util.c
@@ -547,6 +547,13 @@ static int64_t driSwapBuffersMSC( __DRInativeDisplay * dpy, void *drawablePriv,
                                                            remainder );
 }
 
+static void driCopySubBuffer( __DRInativeDisplay *dpy, void *drawablePrivate,
+			      int x, int y, int w, int h)
+{
+    __DRIdrawablePrivate *dPriv = (__DRIdrawablePrivate *) drawablePrivate;
+    dPriv->driScreenPriv->DriverAPI.CopySubBuffer(dPriv, x, y, w, h);
+    (void) dpy;
+}
 
 /**
  * This is called via __DRIscreenRec's createNewDrawable pointer.
@@ -623,6 +630,9 @@ static void *driCreateNewDrawable(__DRInativeDisplay *dpy,
     pdraw->frameTracking = NULL;
     pdraw->queryFrameTracking = driQueryFrameTracking;
 
+    if (driCompareGLXAPIVersion (20060314) >= 0)
+	pdraw->copySubBuffer = driCopySubBuffer;
+
     /* This special default value is replaced with the configured
      * default value when the drawable is first bound to a direct
      * rendering context. 
diff --git a/src/mesa/drivers/dri/common/dri_util.h b/src/mesa/drivers/dri/common/dri_util.h
index b9b38f39cd..14c24a0efa 100644
--- a/src/mesa/drivers/dri/common/dri_util.h
+++ b/src/mesa/drivers/dri/common/dri_util.h
@@ -189,6 +189,8 @@ struct __DriverAPIRec {
     int64_t (*SwapBuffersMSC)( __DRIdrawablePrivate *priv, int64_t target_msc,
 			       int64_t divisor, int64_t remainder );
     /*@}*/
+    void (*CopySubBuffer)(__DRIdrawablePrivate *driDrawPriv,
+			  int x, int y, int w, int h);
 };
 
 
diff --git a/src/mesa/drivers/dri/i915/intel_batchbuffer.c b/src/mesa/drivers/dri/i915/intel_batchbuffer.c
index 508900de30..974a2497e1 100644
--- a/src/mesa/drivers/dri/i915/intel_batchbuffer.c
+++ b/src/mesa/drivers/dri/i915/intel_batchbuffer.c
@@ -366,7 +366,8 @@ static void intelWaitForFrameCompletion( intelContextPtr intel )
 /*
  * Copy the back buffer to the front buffer. 
  */
-void intelCopyBuffer( const __DRIdrawablePrivate *dPriv ) 
+void intelCopyBuffer( const __DRIdrawablePrivate *dPriv,
+		      const drm_clip_rect_t	 *rect)
 {
    intelContextPtr intel;
    GLboolean   missed_target;
@@ -385,15 +386,19 @@ void intelCopyBuffer( const __DRIdrawablePrivate *dPriv )
    
    LOCK_HARDWARE( intel );
    intelWaitForFrameCompletion( intel );
-   UNLOCK_HARDWARE( intel );
-   driWaitForVBlank( dPriv, &intel->vbl_seq, intel->vblank_flags, & missed_target );
 
-   LOCK_HARDWARE( intel );
+   if (!rect)
+   {
+       UNLOCK_HARDWARE( intel );
+       driWaitForVBlank( dPriv, &intel->vbl_seq, intel->vblank_flags, & missed_target );
+       LOCK_HARDWARE( intel );
+   }
    {
       const intelScreenPrivate *intelScreen = intel->intelScreen;
       const __DRIdrawablePrivate *dPriv = intel->driDrawable;
       const int nbox = dPriv->numClipRects;
       const drm_clip_rect_t *pbox = dPriv->pClipRects;
+      drm_clip_rect_t box;
       const int cpp = intelScreen->cpp;
       const int pitch = intelScreen->front.pitch; /* in bytes */
       int i;
@@ -429,18 +434,35 @@ void intelCopyBuffer( const __DRIdrawablePrivate *dPriv )
 	    continue;
          }
 
+	 box = *pbox;
+
+	 if (rect)
+	 {
+	     if (rect->x1 > box.x1)
+		 box.x1 = rect->x1;
+	     if (rect->y1 > box.y1)
+		 box.y1 = rect->y1;
+	     if (rect->x2 < box.x2)
+		 box.x2 = rect->x2;
+	     if (rect->y2 < box.y2)
+		 box.y2 = rect->y2;
+
+	     if (box.x1 > box.x2 || box.y1 > box.y2)
+		 continue;
+	 }
+
 	 BEGIN_BATCH( 8);
 	 OUT_BATCH( CMD );
 	 OUT_BATCH( BR13 );
-	 OUT_BATCH( (pbox->y1 << 16) | pbox->x1 );
-	 OUT_BATCH( (pbox->y2 << 16) | pbox->x2 );
+	 OUT_BATCH( (box.y1 << 16) | box.x1 );
+	 OUT_BATCH( (box.y2 << 16) | box.x2 );
 
 	 if (intel->sarea->pf_current_page == 0) 
 	    OUT_BATCH( intelScreen->front.offset );
 	 else
 	    OUT_BATCH( intelScreen->back.offset );			
 
-	 OUT_BATCH( (pbox->y1 << 16) | pbox->x1 );
+	 OUT_BATCH( (box.y1 << 16) | box.x1 );
 	 OUT_BATCH( BR13 & 0xffff );
 
 	 if (intel->sarea->pf_current_page == 0) 
@@ -454,14 +476,17 @@ void intelCopyBuffer( const __DRIdrawablePrivate *dPriv )
    intelFlushBatchLocked( intel, GL_TRUE, GL_TRUE, GL_TRUE );
    UNLOCK_HARDWARE( intel );
 
-   intel->swap_count++;
-   (*dri_interface->getUST)(&ust);
-   if (missed_target) {
-     intel->swap_missed_count++;
-     intel->swap_missed_ust = ust -  intel->swap_ust;
-   }
+   if (!rect)
+   {
+       intel->swap_count++;
+       (*dri_interface->getUST)(&ust);
+       if (missed_target) {
+	   intel->swap_missed_count++;
+	   intel->swap_missed_ust = ust -  intel->swap_ust;
+       }
    
-   intel->swap_ust = ust;
+       intel->swap_ust = ust;
+   }
 }
 
 
diff --git a/src/mesa/drivers/dri/i915/intel_batchbuffer.h b/src/mesa/drivers/dri/i915/intel_batchbuffer.h
index dcc63b23c8..b0aed89af5 100644
--- a/src/mesa/drivers/dri/i915/intel_batchbuffer.h
+++ b/src/mesa/drivers/dri/i915/intel_batchbuffer.h
@@ -75,7 +75,8 @@ extern void intelRestartInlinePrimitive( intelContextPtr intel );
 extern GLuint *intelEmitInlinePrimitiveLocked(intelContextPtr intel, 
 					      int primitive, int dwords,
 					      int vertex_size);
-extern void intelCopyBuffer( const __DRIdrawablePrivate *dpriv );
+extern void intelCopyBuffer( const __DRIdrawablePrivate *dpriv,
+			     const drm_clip_rect_t	*rect);
 extern void intelClearWithBlit(GLcontext *ctx, GLbitfield mask, GLboolean all,
 			     GLint cx1, GLint cy1, GLint cw, GLint ch);
 
diff --git a/src/mesa/drivers/dri/i915/intel_context.c b/src/mesa/drivers/dri/i915/intel_context.c
index c79ce9661c..7dbc2c8739 100644
--- a/src/mesa/drivers/dri/i915/intel_context.c
+++ b/src/mesa/drivers/dri/i915/intel_context.c
@@ -722,7 +722,7 @@ void intelSwapBuffers( __DRIdrawablePrivate *dPriv )
 	 if ( 0 /*intel->doPageFlip*/ ) { /* doPageFlip is never set !!! */
 	    intelPageFlip( dPriv );
 	 } else {
-	    intelCopyBuffer( dPriv );
+	     intelCopyBuffer( dPriv, NULL );
 	 }
          if (screen->current_rotation != 0) {
             intelRotateWindow(intel, dPriv, BUFFER_BIT_FRONT_LEFT);
@@ -734,6 +734,29 @@ void intelSwapBuffers( __DRIdrawablePrivate *dPriv )
    }
 }
 
+void intelCopySubBuffer( __DRIdrawablePrivate *dPriv,
+			 int x, int y, int w, int h )
+{
+   if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
+      intelContextPtr intel;
+      GLcontext *ctx;
+      intel = (intelContextPtr) dPriv->driContextPriv->driverPrivate;
+      ctx = &intel->ctx;
+      if (ctx->Visual.doubleBufferMode) {
+         intelScreenPrivate *screen = intel->intelScreen;
+	 drm_clip_rect_t rect;
+	 rect.x1 = x + dPriv->x;
+	 rect.y1 = (dPriv->h - y - h) + dPriv->y;
+	 rect.x2 = rect.x1 + w;
+	 rect.y2 = rect.y1 + h;
+	 _mesa_notifySwapBuffers( ctx );  /* flush pending rendering comands */
+	 intelCopyBuffer( dPriv, &rect );
+      }
+   } else {
+      /* XXX this shouldn't be an error but we can't handle it for now */
+      fprintf(stderr, "%s: drawable has no context!\n", __FUNCTION__);
+   }
+}
 
 void intelInitState( GLcontext *ctx )
 {
diff --git a/src/mesa/drivers/dri/i915/intel_screen.c b/src/mesa/drivers/dri/i915/intel_screen.c
index 9ee44ea086..c8649d8243 100644
--- a/src/mesa/drivers/dri/i915/intel_screen.c
+++ b/src/mesa/drivers/dri/i915/intel_screen.c
@@ -341,6 +341,7 @@ static GLboolean intelInitDriver(__DRIscreenPrivate *sPriv)
       (*glx_enable_extension)( psc, "GLX_MESA_swap_frame_usage" );
       (*glx_enable_extension)( psc, "GLX_SGI_make_current_read" );
       (*glx_enable_extension)( psc, "GLX_MESA_allocate_memory" );
+      (*glx_enable_extension)( psc, "GLX_MESA_copy_sub_buffer" );
    }
    
    sPriv->psc->allocateMemory = (void *) intelAllocateMemoryMESA;
@@ -534,7 +535,8 @@ static const struct __DriverAPIRec intelAPI = {
    .GetMSC          = driGetMSC32,
    .WaitForMSC      = driWaitForMSC32,
    .WaitForSBC      = NULL,
-   .SwapBuffersMSC  = NULL
+   .SwapBuffersMSC  = NULL,
+   .CopySubBuffer   = intelCopySubBuffer
 };
 
 
diff --git a/src/mesa/drivers/dri/i915/intel_screen.h b/src/mesa/drivers/dri/i915/intel_screen.h
index 0cdcc14044..24cfd9bf8b 100644
--- a/src/mesa/drivers/dri/i915/intel_screen.h
+++ b/src/mesa/drivers/dri/i915/intel_screen.h
@@ -106,4 +106,7 @@ intelMakeCurrent(__DRIcontextPrivate *driContextPriv,
 extern void
 intelSwapBuffers(__DRIdrawablePrivate *dPriv);
 
+extern void
+intelCopySubBuffer( __DRIdrawablePrivate *dPriv, int x, int y, int w, int h );
+
 #endif
diff --git a/src/mesa/drivers/dri/r200/r200_context.c b/src/mesa/drivers/dri/r200/r200_context.c
index 0d7df499c0..e4d9e264bf 100644
--- a/src/mesa/drivers/dri/r200/r200_context.c
+++ b/src/mesa/drivers/dri/r200/r200_context.c
@@ -637,7 +637,7 @@ r200SwapBuffers( __DRIdrawablePrivate *dPriv )
             r200PageFlip( dPriv );
          }
          else {
-            r200CopyBuffer( dPriv );
+	     r200CopyBuffer( dPriv, NULL );
          }
       }
    }
@@ -647,6 +647,30 @@ r200SwapBuffers( __DRIdrawablePrivate *dPriv )
    }
 }
 
+void
+r200CopySubBuffer( __DRIdrawablePrivate *dPriv,
+		   int x, int y, int w, int h )
+{
+   if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
+      r200ContextPtr rmesa;
+      GLcontext *ctx;
+      rmesa = (r200ContextPtr) dPriv->driContextPriv->driverPrivate;
+      ctx = rmesa->glCtx;
+      if (ctx->Visual.doubleBufferMode) {
+	 drm_clip_rect_t rect;
+	 rect.x1 = x + dPriv->x;
+	 rect.y1 = (dPriv->h - y - h) + dPriv->y;
+	 rect.x2 = rect.x1 + w;
+	 rect.y2 = rect.y1 + h;
+         _mesa_notifySwapBuffers( ctx );  /* flush pending rendering comands */
+	 r200CopyBuffer( dPriv, &rect );
+      }
+   }
+   else {
+      /* XXX this shouldn't be an error but we can't handle it for now */
+      _mesa_problem(NULL, "%s: drawable has no context!", __FUNCTION__);
+   }
+}
 
 /* Force the context `c' to be the current context and associate with it
  * buffer `b'.
diff --git a/src/mesa/drivers/dri/r200/r200_context.h b/src/mesa/drivers/dri/r200/r200_context.h
index eee72bdacb..faf1b96a2b 100644
--- a/src/mesa/drivers/dri/r200/r200_context.h
+++ b/src/mesa/drivers/dri/r200/r200_context.h
@@ -1006,6 +1006,8 @@ extern GLboolean r200CreateContext( const __GLcontextModes *glVisual,
 				    __DRIcontextPrivate *driContextPriv,
 				    void *sharedContextPrivate);
 extern void r200SwapBuffers( __DRIdrawablePrivate *dPriv );
+extern void r200CopySubBuffer( __DRIdrawablePrivate * dPriv,
+			       int x, int y, int w, int h );
 extern GLboolean r200MakeCurrent( __DRIcontextPrivate *driContextPriv,
 				  __DRIdrawablePrivate *driDrawPriv,
 				  __DRIdrawablePrivate *driReadPriv );
diff --git a/src/mesa/drivers/dri/r200/r200_ioctl.c b/src/mesa/drivers/dri/r200/r200_ioctl.c
index 5a2f7e2ad6..ae0f35cb39 100644
--- a/src/mesa/drivers/dri/r200/r200_ioctl.c
+++ b/src/mesa/drivers/dri/r200/r200_ioctl.c
@@ -420,7 +420,8 @@ static void r200WaitForFrameCompletion( r200ContextPtr rmesa )
 
 /* Copy the back color buffer to the front color buffer.
  */
-void r200CopyBuffer( const __DRIdrawablePrivate *dPriv )
+void r200CopyBuffer( const __DRIdrawablePrivate *dPriv,
+		      const drm_clip_rect_t	 *rect)
 {
    r200ContextPtr rmesa;
    GLint nbox, i, ret;
@@ -446,9 +447,12 @@ void r200CopyBuffer( const __DRIdrawablePrivate *dPriv )
     * request at a time.
     */
    r200WaitForFrameCompletion( rmesa );
-   UNLOCK_HARDWARE( rmesa );
-   driWaitForVBlank( dPriv, & rmesa->vbl_seq, rmesa->vblank_flags, & missed_target );
-   LOCK_HARDWARE( rmesa );
+   if (!rect)
+   {
+       UNLOCK_HARDWARE( rmesa );
+       driWaitForVBlank( dPriv, & rmesa->vbl_seq, rmesa->vblank_flags, & missed_target );
+       LOCK_HARDWARE( rmesa );
+   }
 
    nbox = dPriv->numClipRects; /* must be in locked region */
 
@@ -459,8 +463,27 @@ void r200CopyBuffer( const __DRIdrawablePrivate *dPriv )
       GLint n = 0;
 
       for ( ; i < nr ; i++ ) {
-	 *b++ = box[i];
-	 n++;
+
+	  *b = box[i];
+
+	  if (rect)
+	  {
+	     if (rect->x1 > b->x1)
+		 b->x1 = rect->x1;
+	     if (rect->y1 > b->y1)
+		 b->y1 = rect->y1;
+	     if (rect->x2 < b->x2)
+		 b->x2 = rect->x2;
+	     if (rect->y2 < b->y2)
+		 b->y2 = rect->y2;
+
+	     if (b->x1 < b->x2 && b->y1 < b->y2)
+		 b++;
+	  }
+	  else
+	      b++;
+
+	  n++;
       }
       rmesa->sarea->nbox = n;
 
@@ -474,18 +497,21 @@ void r200CopyBuffer( const __DRIdrawablePrivate *dPriv )
    }
 
    UNLOCK_HARDWARE( rmesa );
-   rmesa->hw.all_dirty = GL_TRUE;
+   if (!rect)
+   {
+       rmesa->hw.all_dirty = GL_TRUE;
 
-   rmesa->swap_count++;
-   (*dri_interface->getUST)( & ust );
-   if ( missed_target ) {
-      rmesa->swap_missed_count++;
-      rmesa->swap_missed_ust = ust - rmesa->swap_ust;
-   }
+       rmesa->swap_count++;
+       (*dri_interface->getUST)( & ust );
+       if ( missed_target ) {
+	   rmesa->swap_missed_count++;
+	   rmesa->swap_missed_ust = ust - rmesa->swap_ust;
+       }
 
-   rmesa->swap_ust = ust;
+       rmesa->swap_ust = ust;
 
-   sched_yield();
+       sched_yield();
+   }
 }
 
 void r200PageFlip( const __DRIdrawablePrivate *dPriv )
diff --git a/src/mesa/drivers/dri/r200/r200_ioctl.h b/src/mesa/drivers/dri/r200/r200_ioctl.h
index cf4188afe8..f53752739d 100644
--- a/src/mesa/drivers/dri/r200/r200_ioctl.h
+++ b/src/mesa/drivers/dri/r200/r200_ioctl.h
@@ -90,7 +90,8 @@ extern void r200ReleaseDmaRegion( r200ContextPtr rmesa,
 				    struct r200_dma_region *region,
 				    const char *caller );
 
-extern void r200CopyBuffer( const __DRIdrawablePrivate *drawable );
+extern void r200CopyBuffer( const __DRIdrawablePrivate *drawable,
+			    const drm_clip_rect_t      *rect);
 extern void r200PageFlip( const __DRIdrawablePrivate *drawable );
 extern void r200Flush( GLcontext *ctx );
 extern void r200Finish( GLcontext *ctx );
diff --git a/src/mesa/drivers/dri/r300/radeon_context.c b/src/mesa/drivers/dri/r300/radeon_context.c
index 0a957816db..4e351dd66b 100644
--- a/src/mesa/drivers/dri/r300/radeon_context.c
+++ b/src/mesa/drivers/dri/r300/radeon_context.c
@@ -231,7 +231,7 @@ void radeonSwapBuffers(__DRIdrawablePrivate * dPriv)
 			if (radeon->doPageFlip) {
 				radeonPageFlip(dPriv);
 			} else {
-				radeonCopyBuffer(dPriv);
+			    radeonCopyBuffer(dPriv, NULL);
 			}
 		}
 	} else {
@@ -241,6 +241,31 @@ void radeonSwapBuffers(__DRIdrawablePrivate * dPriv)
 	}
 }
 
+void radeonCopySubBuffer(__DRIdrawablePrivate * dPriv,
+			 int x, int y, int w, int h )
+{
+    if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
+	radeonContextPtr radeon;
+	GLcontext *ctx;
+
+	radeon = (radeonContextPtr) dPriv->driContextPriv->driverPrivate;
+	ctx = radeon->glCtx;
+
+	if (ctx->Visual.doubleBufferMode) {
+	    drm_clip_rect_t rect;
+	    rect.x1 = x + dPriv->x;
+	    rect.y1 = (dPriv->h - y - h) + dPriv->y;
+	    rect.x2 = rect.x1 + w;
+	    rect.y2 = rect.y1 + h;
+	    _mesa_notifySwapBuffers(ctx);	/* flush pending rendering comands */
+	    radeonCopyBuffer(dPriv, &rect);
+	}
+    } else {
+	/* XXX this shouldn't be an error but we can't handle it for now */
+	_mesa_problem(NULL, "%s: drawable has no context!",
+		      __FUNCTION__);
+    }
+}
 
 /* Force the context `c' to be the current context and associate with it
  * buffer `b'.
diff --git a/src/mesa/drivers/dri/r300/radeon_context.h b/src/mesa/drivers/dri/r300/radeon_context.h
index 671c14df03..4eeb4edcfd 100644
--- a/src/mesa/drivers/dri/r300/radeon_context.h
+++ b/src/mesa/drivers/dri/r300/radeon_context.h
@@ -203,6 +203,8 @@ struct radeon_context {
 #define RADEON_CONTEXT(glctx) ((radeonContextPtr)(ctx->DriverCtx))
 
 extern void radeonSwapBuffers(__DRIdrawablePrivate * dPriv);
+extern void radeonCopySubBuffer(__DRIdrawablePrivate * dPriv,
+				int x, int y, int w, int h);
 extern GLboolean radeonInitContext(radeonContextPtr radeon,
 				   struct dd_function_table* functions,
 				   const __GLcontextModes * glVisual,
diff --git a/src/mesa/drivers/dri/r300/radeon_ioctl.c b/src/mesa/drivers/dri/r300/radeon_ioctl.c
index f562762878..798e83c010 100644
--- a/src/mesa/drivers/dri/r300/radeon_ioctl.c
+++ b/src/mesa/drivers/dri/r300/radeon_ioctl.c
@@ -164,7 +164,8 @@ static void radeonWaitForFrameCompletion(radeonContextPtr radeon)
 
 /* Copy the back color buffer to the front color buffer.
  */
-void radeonCopyBuffer(const __DRIdrawablePrivate * dPriv)
+void radeonCopyBuffer(const __DRIdrawablePrivate * dPriv,
+		      const drm_clip_rect_t	 * rect)
 {
 	radeonContextPtr radeon;
 	GLint nbox, i, ret;
@@ -193,10 +194,13 @@ void radeonCopyBuffer(const __DRIdrawablePrivate * dPriv)
 	 * request at a time.
 	 */
 	radeonWaitForFrameCompletion(radeon);
-	UNLOCK_HARDWARE(radeon);
-	driWaitForVBlank(dPriv, &radeon->vbl_seq, radeon->vblank_flags,
-			 &missed_target);
-	LOCK_HARDWARE(radeon);
+	if (!rect)
+	{
+	    UNLOCK_HARDWARE(radeon);
+	    driWaitForVBlank(dPriv, &radeon->vbl_seq, radeon->vblank_flags,
+			     &missed_target);
+	    LOCK_HARDWARE(radeon);
+	}
 
 	nbox = dPriv->numClipRects;	/* must be in locked region */
 
@@ -206,9 +210,28 @@ void radeonCopyBuffer(const __DRIdrawablePrivate * dPriv)
 		drm_clip_rect_t *b = radeon->sarea->boxes;
 		GLint n = 0;
 
-		for (; i < nr; i++) {
-			*b++ = box[i];
-			n++;
+		for ( ; i < nr ; i++ ) {
+
+		    *b = box[i];
+
+		    if (rect)
+		    {
+			if (rect->x1 > b->x1)
+			    b->x1 = rect->x1;
+			if (rect->y1 > b->y1)
+			    b->y1 = rect->y1;
+			if (rect->x2 < b->x2)
+			    b->x2 = rect->x2;
+			if (rect->y2 < b->y2)
+			    b->y2 = rect->y2;
+
+			if (b->x1 < b->x2 && b->y1 < b->y2)
+			    b++;
+		    }
+		    else
+			b++;
+
+		    n++;
 		}
 		radeon->sarea->nbox = n;
 
@@ -223,22 +246,24 @@ void radeonCopyBuffer(const __DRIdrawablePrivate * dPriv)
 	}
 
 	UNLOCK_HARDWARE(radeon);
-
-	if (IS_R200_CLASS(radeon->radeonScreen))
+	if (!rect)
+	{
+	    if (IS_R200_CLASS(radeon->radeonScreen))
 		((r200ContextPtr)radeon)->hw.all_dirty = GL_TRUE;
-	else
+	    else
 		((r300ContextPtr)radeon)->hw.all_dirty = GL_TRUE;
 
-	radeon->swap_count++;
-	(*dri_interface->getUST) (&ust);
-	if (missed_target) {
+	    radeon->swap_count++;
+	    (*dri_interface->getUST) (&ust);
+	    if (missed_target) {
 		radeon->swap_missed_count++;
 		radeon->swap_missed_ust = ust - radeon->swap_ust;
-	}
+	    }
 
-	radeon->swap_ust = ust;
+	    radeon->swap_ust = ust;
 
-	sched_yield();
+	    sched_yield();
+	}
 }
 
 void radeonPageFlip(const __DRIdrawablePrivate * dPriv)
diff --git a/src/mesa/drivers/dri/r300/radeon_ioctl.h b/src/mesa/drivers/dri/r300/radeon_ioctl.h
index 4ddd776602..b53767510e 100644
--- a/src/mesa/drivers/dri/r300/radeon_ioctl.h
+++ b/src/mesa/drivers/dri/r300/radeon_ioctl.h
@@ -44,7 +44,8 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include "r200_context.h"
 #include "radeon_drm.h"
 
-extern void radeonCopyBuffer(const __DRIdrawablePrivate * drawable);
+extern void radeonCopyBuffer(const __DRIdrawablePrivate * drawable,
+			     const drm_clip_rect_t	* rect);
 extern void radeonPageFlip(const __DRIdrawablePrivate * drawable);
 extern void radeonFlush(GLcontext * ctx);
 extern void radeonFinish(GLcontext * ctx);
diff --git a/src/mesa/drivers/dri/radeon/radeon_context.c b/src/mesa/drivers/dri/radeon/radeon_context.c
index f546731ad4..791d1a37bc 100644
--- a/src/mesa/drivers/dri/radeon/radeon_context.c
+++ b/src/mesa/drivers/dri/radeon/radeon_context.c
@@ -572,7 +572,7 @@ radeonSwapBuffers( __DRIdrawablePrivate *dPriv )
             radeonPageFlip( dPriv );
          }
          else {
-            radeonCopyBuffer( dPriv );
+	     radeonCopyBuffer( dPriv, NULL );
          }
       }
    }
@@ -582,6 +582,31 @@ radeonSwapBuffers( __DRIdrawablePrivate *dPriv )
    }
 }
 
+void radeonCopySubBuffer(__DRIdrawablePrivate * dPriv,
+			 int x, int y, int w, int h )
+{
+    if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
+	radeonContextPtr radeon;
+	GLcontext *ctx;
+
+	radeon = (radeonContextPtr) dPriv->driContextPriv->driverPrivate;
+	ctx = radeon->glCtx;
+
+	if (ctx->Visual.doubleBufferMode) {
+	    drm_clip_rect_t rect;
+	    rect.x1 = x + dPriv->x;
+	    rect.y1 = (dPriv->h - y - h) + dPriv->y;
+	    rect.x2 = rect.x1 + w;
+	    rect.y2 = rect.y1 + h;
+	    _mesa_notifySwapBuffers(ctx);	/* flush pending rendering comands */
+	    radeonCopyBuffer(dPriv, &rect);
+	}
+    } else {
+	/* XXX this shouldn't be an error but we can't handle it for now */
+	_mesa_problem(NULL, "%s: drawable has no context!",
+		      __FUNCTION__);
+    }
+}
 
 /* Make context `c' the current context and bind it to the given
  * drawing and reading surfaces.
diff --git a/src/mesa/drivers/dri/radeon/radeon_context.h b/src/mesa/drivers/dri/radeon/radeon_context.h
index 09fa948ccb..9abd866730 100644
--- a/src/mesa/drivers/dri/radeon/radeon_context.h
+++ b/src/mesa/drivers/dri/radeon/radeon_context.h
@@ -850,6 +850,8 @@ extern GLboolean radeonCreateContext(const __GLcontextModes *glVisual,
 				     __DRIcontextPrivate *driContextPriv,
 				     void *sharedContextPrivate);
 extern void radeonSwapBuffers( __DRIdrawablePrivate *dPriv );
+extern void radeonCopySubBuffer(__DRIdrawablePrivate * dPriv,
+				int x, int y, int w, int h);
 extern GLboolean radeonMakeCurrent( __DRIcontextPrivate *driContextPriv,
 				    __DRIdrawablePrivate *driDrawPriv,
 				    __DRIdrawablePrivate *driReadPriv );
diff --git a/src/mesa/drivers/dri/radeon/radeon_ioctl.c b/src/mesa/drivers/dri/radeon/radeon_ioctl.c
index fa22cbd6f9..53f6f57057 100644
--- a/src/mesa/drivers/dri/radeon/radeon_ioctl.c
+++ b/src/mesa/drivers/dri/radeon/radeon_ioctl.c
@@ -875,7 +875,8 @@ static void radeonWaitForFrameCompletion( radeonContextPtr rmesa )
 
 /* Copy the back color buffer to the front color buffer.
  */
-void radeonCopyBuffer( const __DRIdrawablePrivate *dPriv )
+void radeonCopyBuffer( const __DRIdrawablePrivate *dPriv,
+		       const drm_clip_rect_t	  *rect)
 {
    radeonContextPtr rmesa;
    GLint nbox, i, ret;
@@ -899,9 +900,12 @@ void radeonCopyBuffer( const __DRIdrawablePrivate *dPriv )
     * request at a time.
     */
    radeonWaitForFrameCompletion( rmesa );
-   UNLOCK_HARDWARE( rmesa );
-   driWaitForVBlank( dPriv, & rmesa->vbl_seq, rmesa->vblank_flags, & missed_target );
-   LOCK_HARDWARE( rmesa );
+   if (!rect)
+   {
+       UNLOCK_HARDWARE( rmesa );
+       driWaitForVBlank( dPriv, & rmesa->vbl_seq, rmesa->vblank_flags, & missed_target );
+       LOCK_HARDWARE( rmesa );
+   }
 
    nbox = dPriv->numClipRects; /* must be in locked region */
 
@@ -912,8 +916,27 @@ void radeonCopyBuffer( const __DRIdrawablePrivate *dPriv )
       GLint n = 0;
 
       for ( ; i < nr ; i++ ) {
-	 *b++ = box[i];
-	 n++;
+
+	  *b = box[i];
+
+	  if (rect)
+	  {
+	      if (rect->x1 > b->x1)
+		  b->x1 = rect->x1;
+	      if (rect->y1 > b->y1)
+		  b->y1 = rect->y1;
+	      if (rect->x2 < b->x2)
+		  b->x2 = rect->x2;
+	      if (rect->y2 < b->y2)
+		  b->y2 = rect->y2;
+
+	      if (b->x1 < b->x2 && b->y1 < b->y2)
+		  b++;
+	  }
+	  else
+	      b++;
+
+	  n++;
       }
       rmesa->sarea->nbox = n;
 
@@ -927,15 +950,18 @@ void radeonCopyBuffer( const __DRIdrawablePrivate *dPriv )
    }
 
    UNLOCK_HARDWARE( rmesa );
-   rmesa->swap_count++;
-   (*dri_interface->getUST)( & ust );
-   if ( missed_target ) {
-      rmesa->swap_missed_count++;
-      rmesa->swap_missed_ust = ust - rmesa->swap_ust;
+   if (!rect)
+   {
+       rmesa->swap_count++;
+       (*dri_interface->getUST)( & ust );
+       if ( missed_target ) {
+	   rmesa->swap_missed_count++;
+	   rmesa->swap_missed_ust = ust - rmesa->swap_ust;
+       }
+
+       rmesa->swap_ust = ust;
+       rmesa->hw.all_dirty = GL_TRUE;
    }
-
-   rmesa->swap_ust = ust;
-   rmesa->hw.all_dirty = GL_TRUE;
 }
 
 void radeonPageFlip( const __DRIdrawablePrivate *dPriv )
diff --git a/src/mesa/drivers/dri/radeon/radeon_ioctl.h b/src/mesa/drivers/dri/radeon/radeon_ioctl.h
index dd7ed19b84..335ed77c9a 100644
--- a/src/mesa/drivers/dri/radeon/radeon_ioctl.h
+++ b/src/mesa/drivers/dri/radeon/radeon_ioctl.h
@@ -87,7 +87,8 @@ extern void radeonReleaseDmaRegion( radeonContextPtr rmesa,
 				    struct radeon_dma_region *region,
 				    const char *caller );
 
-extern void radeonCopyBuffer( const __DRIdrawablePrivate *drawable );
+extern void radeonCopyBuffer( const __DRIdrawablePrivate *drawable,
+			      const drm_clip_rect_t	 *rect);
 extern void radeonPageFlip( const __DRIdrawablePrivate *drawable );
 extern void radeonFlush( GLcontext *ctx );
 extern void radeonFinish( GLcontext *ctx );
diff --git a/src/mesa/drivers/dri/radeon/radeon_screen.c b/src/mesa/drivers/dri/radeon/radeon_screen.c
index a93cfb3821..5257e541e5 100644
--- a/src/mesa/drivers/dri/radeon/radeon_screen.c
+++ b/src/mesa/drivers/dri/radeon/radeon_screen.c
@@ -716,6 +716,8 @@ radeonCreateScreen( __DRIscreenPrivate *sPriv )
       (*glx_enable_extension)( psc, "GLX_MESA_swap_frame_usage" );
       if (IS_R200_CLASS(screen))
 	 (*glx_enable_extension)( psc, "GLX_MESA_allocate_memory" );
+
+      (*glx_enable_extension)( psc, "GLX_MESA_copy_sub_buffer" );
    }
 
 #if RADEON_COMMON && defined(RADEON_COMMON_FOR_R200)
@@ -923,7 +925,8 @@ static struct __DriverAPIRec radeonAPI = {
    .GetMSC          = driGetMSC32,
    .WaitForMSC      = driWaitForMSC32,
    .WaitForSBC      = NULL,
-   .SwapBuffersMSC  = NULL
+   .SwapBuffersMSC  = NULL,
+   .CopySubBuffer   = radeonCopySubBuffer,
 };
 #else
 static const struct __DriverAPIRec r200API = {
@@ -940,7 +943,8 @@ static const struct __DriverAPIRec r200API = {
    .GetMSC          = driGetMSC32,
    .WaitForMSC      = driWaitForMSC32,
    .WaitForSBC      = NULL,
-   .SwapBuffersMSC  = NULL
+   .SwapBuffersMSC  = NULL,
+   .CopySubBuffer   = r200CopySubBuffer
 };
 #endif