Add SwapBuffers request

Add a SwapBuffers request for requesting a front<->back swap.  Returns a
whole new set of buffers to the client to allow for triple buffering
etc.

1 files changed, 41 insertions, 0 deletions

diff --git a/dri2proto.txt b/dri2proto.txt
index e931bfb..bad9567 100644
--- a/dri2proto.txt
+++ b/dri2proto.txt
@@ -105,6 +105,11 @@ DRI2 implementation of direct rendering GLX, should use these enty
 points to copy contents back and forth to as necessary to ensure
 consistent rendering.
 
+The client may also use the DRI2SwapBuffers function to request a swap
+of the front and back buffers.  If the display server supports it, this
+operation may be preferred, since it may be easier and/or more performant
+for the server to perform a simple buffer swap rather than a blit.
+
 
 			     ⚙ ⚙ ⚙  ⚙ ⚙ ⚙
 
@@ -288,6 +293,21 @@ The name of this extension is "DRI2".
 	the server has seen the request before proceeding with
 	rendering the next frame.
 
+┌───
+    DRI2SwapBuffers
+	drawable: DRAWABLE
+      ▶	
+	buffers: LISTofDRI2BUFFER
+└───
+	Errors: Window
+
+	Schedule a swap of the front and back buffers with the display
+	server.
+
+	In reply, the display server is expected to provide new front
+	and back buffers to the client following this request.  The
+	display server should process this request asynchronously
+	if possible, to prevent the client from blocking.
 
 ┌───
     DRI2GetBuffersWithFormat
@@ -542,6 +562,27 @@ A.3 Protocol Events
 
 The DRI2 extension specifies no events.
 
+┌───
+    DRI2SwapBuffers
+	1	CARD8			major opcode
+	1	7			DRI2 opcode
+	2	8			length
+	4	DRAWABLE		drawable
+      ▶	
+	1	1			Reply
+        1				unused
+	2	CARD16			sequence number
+	4	0			reply length
+	4	CARD32			buffer count
+	4	CARD32			unused
+	4	CARD32			unused
+	4	CARD32			unused
+	4	CARD32			unused
+	4	CARD32			unused
+	4	CARD32			unused
+	5n	LISTofDRI2BUFFER	buffers
+└───
+
 
 A.4 Protocol Errors