commit e3e098cbd389e6e99f43b62721d3f75f76ffec9f
author Daniel Kurtz <djkurtz@chromium.org> Mon Apr 09 08:18:51 2012
committer Daniel Kurtz <djkurtz@chromium.org> Mon Apr 09 08:18:51 2012
tree ab1391c72cf1328e27781507cc179ac0d892b483
parent c20d0e85ade1622f899f127bb9d127b70c8f747c

Add default true persist option to display positions with persistence

Setting --persist=0 will cause only the current detected contact positions
to be plotted.  This behavior can be toggled at run time by pressing the
'p' key.

BUG=chromium-os:29063
TEST=mtplot --persist=1 # shows persistent dots
TEST=mtplot --persist=0 # does not show persistent dots

Change-Id: I1d70dd89e8880423a26fae4534c01ec7a0658d1e

mtplot.c

diff --git a/mtplot.c b/mtplot.c
index b89291f..d6c5174 100644
--- a/mtplot.c
+++ b/mtplot.c
@@ -431,6 +431,7 @@
 
 // Program Options
 bool monotonic = true;
+bool persist = true;
 
 static Display *dpy;
 static unsigned long blackColor;
@@ -555,6 +556,8 @@
 
 static void MtStatePaint(struct mt_state *s) {
   int i;
+  if (!persist)
+    XClearWindow(dpy, w);
   for (i = slot_min; i <= slot_max; i++)
     MtSlotPaint(&s->slot[i - slot_min]);
   XFlush(dpy);
@@ -825,18 +828,22 @@
 static const struct option long_options[] = {
   { "display", required_argument, NULL, 'd' },
   { "monotonic", optional_argument, NULL, 'm' },
+  { "persist", optional_argument, NULL, 'p' },
   { 0, },
 };
 
 // Print usage information.
 static int Usage(void) {
   printf("USAGE:\n");
-  printf("   %s /dev/input/eventX [--display DISPLAY] [--monotonic]\n",
+  printf("   %s /dev/input/eventX [--display DISPLAY] [--monotonic] [--persist]\n",
          program_invocation_short_name);
   printf("\n");
   printf(" -m, --monotonic[=0|1]  =1: requests input events with monotonic timestamps\n"
          "                            if supported by the kernel (default)\n"
          "                        =0: request input events with wallclock timestamps\n");
+  printf(" -p, --persist[=0|1]    =1: display persistent trails for each contact (default)\n"
+         "                        =0: only display the current contact positions\n"
+         "                            To toggle at runtime press 'p'\n");
 
   return EXIT_FAILURE;
 }
@@ -852,7 +859,7 @@
   fd_set rdfs;
 
   while (1) {
-    int c = getopt_long_only(argc, argv, "d:m:", long_options, NULL);
+    int c = getopt_long_only(argc, argv, "d:m:p:", long_options, NULL);
     if (c == -1)
       break;
     switch (c) {
@@ -862,6 +869,9 @@
       case 'm':
         monotonic = (optarg) ? atoi(optarg) : true;
         break;
+      case 'p':
+        persist = (optarg) ? atoi(optarg) : true;
+        break;
       default:  // Fall through case
         printf("Unknown option '%c'\n", c);
       case '?':
@@ -996,6 +1006,8 @@
           KeySym ks = XLookupKeysym(&xke, 0);
           if (ks == XK_Escape)
             XClearWindow(dpy, w);
+          else if (ks == XK_p)
+            persist = !persist;
         }
       }
     }