present demo: support multiple pixmaps

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 119 insertions, 27 deletions

diff --git a/present.c b/present.c
index f992f6d..a67893b 100644
--- a/present.c
+++ b/present.c
@@ -18,11 +18,15 @@
 #include <stdio.h>
 #include <stddef.h>
 #include <stdlib.h>
+#include <unistd.h>
+#include <stdbool.h>
 #include <time.h>
 #include <sys/mman.h>
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
 #include <xcb/present.h>
+#include <xcb/xfixes.h>
+#include <xcb/sync.h>
 
 #define	INIT_WIDTH	500
 #define INIT_HEIGHT	500
@@ -34,9 +38,14 @@ xcb_screen_t		*screen;
 xcb_gc_t		gc;
 xcb_present_event_t	present_event;
 xcb_window_t		window;
-xcb_pixmap_t		pixmap;
+xcb_xfixes_region_t	update;
+#define NPIXMAP	3
+xcb_pixmap_t		pixmap[NPIXMAP];
+bool			busy[NPIXMAP];
 xcb_generic_event_t	*event;
 xcb_generic_error_t	*error;
+xcb_sync_fence_t	wait_fence;
+int			using_fence;
 const xcb_query_extension_reply_t	*present_extension;
 uint32_t		window_mask;
 uint32_t		window_values[5];
@@ -49,29 +58,54 @@ int			x;
 int			x_inc = 30;
 uint64_t		msc;
 uint64_t		target_msc;
+int			interval = 0;
+uint32_t		serial;
+uint32_t		options = 0; // XCB_PRESENT_OPTION_ASYNC;
 
-static void make_pixmap(void)
+static void make_pixmap(int i)
 {
 	xcb_create_pixmap(c,
 			  24,
-			  (pixmap = xcb_generate_id(c)),
+			  (pixmap[i] = xcb_generate_id(c)),
 			  window,
 			  width,
 			  height);
 }
 
+static void make_update(void)
+{
+	return;
+	xcb_rectangle_t	rect = { .x = 0, .y = 0, .width = width, .height = height };
+
+	xcb_xfixes_create_region(c,
+				 (update = xcb_generate_id(c)),
+				 1,
+				 &rect);
+}
+
 static void discard_pixmap(void)
 {
-	if (pixmap) {
-		xcb_free_pixmap (c, pixmap);
-		pixmap = 0;
+	int i;
+	for (i = 0; i < NPIXMAP; i++) {
+		if (pixmap[i]) {
+			xcb_free_pixmap (c, pixmap[i]);
+			pixmap[i] = 0;
+		}
+	}
+
+	if (update) {
+		xcb_xfixes_destroy_region(c, update);
+		update = 0;
 	}
 }
 
-static void draw(void)
+static void draw(int i)
 {
-	if (!pixmap)
-		make_pixmap();
+	if (!pixmap[i])
+		make_pixmap(i);
+
+	if (!update)
+		make_update();
 
 	gc_mask = XCB_GC_FOREGROUND;
 	gc_values[0] = 0xffffffff;
@@ -80,7 +114,7 @@ static void draw(void)
 	rectangle.y = 0;
 	rectangle.width = width;
 	rectangle.height = height;
-	xcb_poly_fill_rectangle(c, pixmap, gc, 1, &rectangle);
+	xcb_poly_fill_rectangle(c, pixmap[i], gc, 1, &rectangle);
 
 	gc_mask = XCB_GC_FOREGROUND;
 	gc_values[0] = 0x0;
@@ -90,7 +124,7 @@ static void draw(void)
 	rectangle.y = 0;
 	rectangle.width = 60;
 	rectangle.height = height;
-	xcb_poly_fill_rectangle(c, pixmap, gc, 1, &rectangle);
+	xcb_poly_fill_rectangle(c, pixmap[i], gc, 1, &rectangle);
 
 	x += x_inc;
 	if (x_inc > 0) {
@@ -104,20 +138,20 @@ static void draw(void)
 
 #define None 0
 
-static void show(void)
+static void show(int i)
 {
 	xcb_present_pixmap (c,
 			    window,
-			    pixmap,
-			    0,
-			    None,
+			    pixmap[i],
+			    i,
 			    None,
+			    update,
 			    0,
 			    0,
 			    None,
+			    using_fence ? wait_fence : None,
 			    None,
-			    None,
-			    0,
+			    options,
 			    target_msc,
 			    0,
 			    0,
@@ -126,6 +160,9 @@ static void show(void)
 }
 
 int		frame_count;
+int		skip_count;
+int		copy_count;
+int		flip_count;
 uint32_t	start_time;
 uint32_t	end_time;
 
@@ -139,10 +176,16 @@ millis(void)
 
 static void frame(void)
 {
-	draw();
-	target_msc = msc + 1;
-	show();
-	++frame_count;
+	int	p;
+
+	for (p = 0; p < NPIXMAP; p++) {
+		if (!busy[p]) {
+			busy[p] = true;
+			draw(p);
+			target_msc += interval;
+			show(p);
+		}
+	}
 }
 
 int
@@ -155,9 +198,11 @@ main (int argc, char **argv)
 	}
 	screen = xcb_aux_get_screen(c, screen_num);
 
+	(void) xcb_xfixes_query_version(c, XCB_XFIXES_MAJOR_VERSION, XCB_XFIXES_MINOR_VERSION);
+
 	window_mask = XCB_CW_BACK_PIXEL|XCB_CW_EVENT_MASK;
 	window_values[0] = 0xffffff;
-	window_values[1] = XCB_EVENT_MASK_EXPOSURE;
+	window_values[1] = XCB_EVENT_MASK_EXPOSURE|XCB_EVENT_MASK_KEY_PRESS;
 
 	width = INIT_WIDTH;
 	height = INIT_HEIGHT;
@@ -181,6 +226,11 @@ main (int argc, char **argv)
 		      0,					/* mask */
 		      NULL);					/* values */
 
+	xcb_sync_create_fence(c,
+			      window,
+			      (wait_fence = xcb_generate_id(c)),
+			      0);
+
 	xcb_present_select_input(c,
 				 (present_event = xcb_generate_id(c)),
 				 window,
@@ -191,10 +241,10 @@ main (int argc, char **argv)
 	present_extension = xcb_get_extension_data(c, &xcb_present_id);
 
 	start_time = millis();
-	draw();
+	draw(0);
 
 	xcb_map_window(c, window);
-	show();
+	show(0);
 	xcb_present_notify_msc(c, window, 0, 0, 5 * 60, 0);
 
 	printf ("mapped\n");
@@ -207,6 +257,21 @@ main (int argc, char **argv)
 		switch (event->response_type) {
 		case XCB_EXPOSE:
 			break;
+		case XCB_KEY_PRESS:
+			switch (++using_fence) {
+			case 1:
+				printf ("wait fence\n");
+				break;
+			case 2:
+				printf ("trigger fence\n");
+				xcb_sync_trigger_fence(c, wait_fence);
+				break;
+			case 3:
+				printf ("no fence\n");
+				xcb_sync_reset_fence(c, wait_fence);
+				using_fence = 0;
+			}
+			break;
 		case 0:
 			error = (xcb_generic_error_t *) event;
 			printf ("error %d major %d minor %d\n",
@@ -229,25 +294,52 @@ main (int argc, char **argv)
 				}
 				case XCB_PRESENT_COMPLETE_NOTIFY: {
 					xcb_present_complete_notify_event_t *ce = (void *) event;
+//					printf ("kind %d mode %d\n", ce->kind, ce->mode);
 					if (ce->kind == XCB_PRESENT_COMPLETE_KIND_PIXMAP) {
 						int64_t	diff = ce->msc - target_msc;
 
 						if (diff< 0)
 							diff = -diff;
-						if (diff)
+						if (diff && interval)
 							printf ("target %lld actual %lld\n", target_msc, ce->msc);
+						++frame_count;
+						switch (ce->mode) {
+						case XCB_PRESENT_COMPLETE_MODE_COPY:
+							++copy_count;
+							break;
+						case XCB_PRESENT_COMPLETE_MODE_SKIP:
+							++skip_count;
+							break;
+						case XCB_PRESENT_COMPLETE_MODE_FLIP:
+							++flip_count;
+							break;
+						}
 						msc = ce->msc;
-						frame();
+						target_msc = msc + interval;
+						if (interval)
+							frame();
 					} else {
 						xcb_present_notify_msc(c, window, 0, 0, 5 * 60, 0);
 						end_time = millis();
 						double seconds = (end_time - start_time) / 1000.0;
-						printf ("%5d frames in %8.3f seconds. frame rate: %f\n", frame_count, seconds, (double) frame_count / ((double) (end_time - start_time) / 1000.0));
+						printf ("%5d frames in %8.3f seconds. frame rate: %f copy %d skip %d flip %d\n",
+							frame_count, seconds, (double) frame_count / ((double) (end_time - start_time) / 1000.0),
+							copy_count, skip_count, flip_count);
 						frame_count = 0;
+						copy_count = 0;
+						skip_count = 0;
+						flip_count = 0;
 						start_time = millis();
 					}
 					break;
 				}
+				case XCB_PRESENT_IDLE_NOTIFY: {
+					xcb_present_idle_notify_event_t *ie = (void *) event;
+					busy[ie->serial] = false;
+					if (!interval)
+						frame();
+					break;
+				}
 				}
 			}
 			break;