Mesa (master): Add glsync demo program from jbarnes for testing vblank synchronization.

Eric Anholt anholt at kemper.freedesktop.org
Wed Nov 12 21:59:15 UTC 2008


Module: Mesa
Branch: master
Commit: 72bbc89534f682579ab49a7259203724d07db942
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=72bbc89534f682579ab49a7259203724d07db942

Author: Eric Anholt <eric at anholt.net>
Date:   Tue Nov  4 12:34:29 2008 -0800

Add glsync demo program from jbarnes for testing vblank synchronization.

---

 progs/xdemos/.gitignore |    1 +
 progs/xdemos/Makefile   |    1 +
 progs/xdemos/glsync.c   |  273 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 275 insertions(+), 0 deletions(-)

diff --git a/progs/xdemos/.gitignore b/progs/xdemos/.gitignore
index 868249d..084dee5 100644
--- a/progs/xdemos/.gitignore
+++ b/progs/xdemos/.gitignore
@@ -1,4 +1,5 @@
 corender
+glsync
 glthreads
 glxcontexts
 glxdemo
diff --git a/progs/xdemos/Makefile b/progs/xdemos/Makefile
index b259671..f8f2f15 100644
--- a/progs/xdemos/Makefile
+++ b/progs/xdemos/Makefile
@@ -12,6 +12,7 @@ LIBS = -L$(TOP)/$(LIB_DIR) -l$(GL_LIB) $(APP_LIB_DEPS)
 
 PROGS = \
 	corender \
+	glsync \
 	glthreads \
 	glxdemo \
 	glxgears \
diff --git a/progs/xdemos/glsync.c b/progs/xdemos/glsync.c
new file mode 100644
index 0000000..95cd1af
--- /dev/null
+++ b/progs/xdemos/glsync.c
@@ -0,0 +1,273 @@
+/*
+ * Copyright © 2007 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Authors:
+ *    Jesse Barnes <jesse.barnes at intel.com>
+ *
+ */
+
+/** @file glsync.c
+ * The program is simple:  it paints a window alternating colors (red &
+ * white) either as fast as possible or synchronized to vblank events
+ *
+ * If run normally, the program should display a window that exhibits
+ * significant tearing between red and white colors (e.g. you might get
+ * a "waterfall" effect of red and white horizontal bars).
+ *
+ * If run with the '-s b' option, the program should synchronize the
+ * window color changes with the vertical blank period, resulting in a
+ * window that looks orangish with a high frequency flicker (which may
+ * be invisible).  If the window is moved to another screen, this
+ * property should be preserved.  If the window spans two screens, it
+ * shouldn't tear on whichever screen most of the window is on; the
+ * portion on the other screen may show some tearing (like the
+ * waterfall effect above).
+ *
+ * Other options include '-w <width>' and '-h <height' to set the
+ * window size.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/glx.h>
+#include <GL/glxext.h>
+#include <X11/X.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+void (*video_sync_get)();
+void (*video_sync)();
+
+static int GLXExtensionSupported(Display *dpy, const char *extension)
+{
+	const char *extensionsString, *client_extensions, *pos;
+
+	extensionsString = glXQueryExtensionsString(dpy, DefaultScreen(dpy));
+	client_extensions = glXGetClientString(dpy, GLX_EXTENSIONS);
+
+	pos = strstr(extensionsString, extension);
+
+	if (pos != NULL && (pos == extensionsString || pos[-1] == ' ') &&
+	    (pos[strlen(extension)] == ' ' || pos[strlen(extension)] == '\0'))
+		return 1;
+
+	pos = strstr(client_extensions, extension);
+
+	if (pos != NULL && (pos == extensionsString || pos[-1] == ' ') &&
+	    (pos[strlen(extension)] == ' ' || pos[strlen(extension)] == '\0'))
+		return 1;
+
+	return 0;
+}
+
+extern char *optarg;
+extern int optind, opterr, optopt;
+static char optstr[] = "w:h:s:v";
+
+enum sync_type {
+	none = 0,
+	sgi_video_sync,
+	buffer_swap,
+};
+
+static void usage(char *name)
+{
+	printf("usage: %s [-w <width>] [-h <height>] [-s<sync method>] "
+	       "[-vc]\n", name);
+	printf("\t-s<sync method>:\n");
+	printf("\t\tn: none\n");
+	printf("\t\ts: SGI video sync extension\n");
+	printf("\t\tb: buffer swap\n");
+	printf("\t-v: verbose (print count)\n");
+	exit(-1);
+}
+
+int main(int argc, char *argv[])
+{
+	Display *disp;
+	XVisualInfo *pvi;
+	XSetWindowAttributes swa;
+	int attrib[14];
+	GLint last_val = -1, count = 0;
+	Window winGL;
+	int dummy;
+	Atom wmDelete;
+	enum sync_type waitforsync = none;
+	int width = 500, height = 500, verbose = 0,
+		countonly = 0;
+	int c, i = 1;
+
+	opterr = 0;
+	while ((c = getopt(argc, argv, optstr)) != -1) {
+		switch (c) {
+		case 'w':
+			width = atoi(optarg);
+			break;
+		case 'h':
+			height = atoi(optarg);
+			break;
+		case 's':
+			switch (optarg[0]) {
+			case 'n':
+				waitforsync = none;
+				break;
+			case 's':
+				waitforsync = sgi_video_sync;
+				break;
+			case 'b':
+				waitforsync = buffer_swap;
+				break;
+			default:
+				usage(argv[0]);
+				break;
+			}
+			break;
+		case 'v':
+			verbose = 1;
+			break;
+		default:
+			usage(argv[0]);
+			break;
+		}
+	}
+
+	disp = XOpenDisplay(NULL);
+	if (!disp) {
+		fprintf(stderr, "failed to open display\n");
+		return -1;
+	}
+
+	if (!glXQueryExtension(disp, &dummy, &dummy)) {
+		fprintf(stderr, "glXQueryExtension failed\n");
+		return -1;
+	}
+
+	if (!GLXExtensionSupported(disp, "GLX_SGI_video_sync")) {
+		fprintf(stderr, "GLX_SGI_video_sync not supported, exiting\n");
+		return -1;
+	}
+
+	attrib[0] = GLX_RGBA;
+	attrib[1] = 1;
+	attrib[2] = GLX_RED_SIZE;
+	attrib[3] = 1;
+	attrib[4] = GLX_GREEN_SIZE;
+	attrib[5] = 1;
+	attrib[6] = GLX_BLUE_SIZE;
+	attrib[7] = 1;
+	if (waitforsync != buffer_swap)
+		attrib[8] = None;
+	else {
+		attrib[8] = GLX_DOUBLEBUFFER;
+		attrib[9] = 1;
+		attrib[10] = None;
+	}
+
+	GLXContext context;
+	pvi = glXChooseVisual(disp, DefaultScreen(disp), attrib);
+	if (!pvi) {
+		fprintf(stderr, "failed to choose visual, exiting\n");
+		return -1;
+	}
+
+	context = glXCreateContext(disp, pvi, None, GL_TRUE);
+	if (!context) {
+		fprintf(stderr, "failed to create glx context\n");
+		return -1;
+	}
+
+	pvi->screen = DefaultScreen(disp);
+
+	swa.colormap = XCreateColormap(disp, RootWindow(disp, pvi->screen),
+				       pvi->visual, AllocNone);
+	swa.border_pixel = 0;
+	swa.event_mask = ExposureMask | KeyPressMask | ButtonPressMask |
+		StructureNotifyMask;
+	winGL = XCreateWindow(disp, RootWindow(disp, pvi->screen),
+			      0, 0,
+			      width, height,
+			      0, pvi->depth, InputOutput, pvi->visual,
+			      CWBorderPixel | CWColormap | CWEventMask, &swa);
+	if (!winGL) {
+		fprintf(stderr, "window creation failed\n");
+		return -1;
+	}
+        wmDelete = XInternAtom(disp, "WM_DELETE_WINDOW", True);
+        XSetWMProtocols(disp, winGL, &wmDelete, 1);
+
+	XSetStandardProperties(disp, winGL, "glsync test", "glsync text",
+			       None, NULL, 0, NULL);
+
+	XMapRaised(disp, winGL);
+
+	glXMakeCurrent(disp, winGL, context);
+
+	video_sync_get = glXGetProcAddress((unsigned char *)"glXGetVideoSyncSGI");
+	video_sync = glXGetProcAddress((unsigned char *)"glXWaitVideoSyncSGI");
+
+	if (!video_sync_get || !video_sync) {
+		fprintf(stderr, "failed to get sync functions\n");
+		return -1;
+	}
+
+	video_sync_get(&count);
+	count++;
+	while (i++) {
+		/* Wait for vsync */
+		if (waitforsync == sgi_video_sync) {
+			if (verbose)
+				fprintf(stderr, "waiting on count %d\n", count);
+			video_sync(2, (count + 1) % 2, &count);
+			if (count < last_val)
+				fprintf(stderr, "error:  vblank count went backwards: %d -> %d\n", last_val, count);
+			if (count == last_val)
+				fprintf(stderr, "error:  count didn't change: %d\n", count);
+			last_val = count;
+		} else if (waitforsync == buffer_swap) {
+			glXSwapBuffers(disp, winGL);
+		}
+
+		if (countonly) {
+			video_sync(2, 1, &count);
+			fprintf(stderr, "current count: %d\n", count);
+			sleep(1);
+			continue;
+		}
+
+		/* Alternate colors to make tearing obvious */
+		if (i & 1)
+			glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
+		else
+			glClearColor(1.0f, 0.0f, 0.0f, 0.0f);
+		glClear(GL_COLOR_BUFFER_BIT);
+		glFlush();
+	}
+
+	XDestroyWindow(disp, winGL);
+	glXDestroyContext(disp, context);
+	XCloseDisplay(disp);
+
+	return 0;
+}




More information about the mesa-commit mailing list