trace-graph: Add cursor line

This patch adds a cursor line when double clicked. This allows the user
to keep a reference to a location when zooming in and out.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

2 files changed, 55 insertions, 11 deletions

diff --git a/trace-graph.c b/trace-graph.c
index e4e50b2..d97c4d1 100644
--- a/trace-graph.c
+++ b/trace-graph.c
@@ -127,6 +127,21 @@ static void draw_cpu_labels(struct graph_info *ginfo)
                 __draw_cpu_label(ginfo, cpu);
 }
 
+static void draw_cursor(struct graph_info *ginfo)
+{
+        gint x;
+
+        if (ginfo->cursor < ginfo->view_start_time ||
+            ginfo->cursor > ginfo->view_end_time)
+                return;
+
+        x = (ginfo->cursor - ginfo->view_start_time)
+                * ginfo->resolution;
+
+        gdk_draw_line(ginfo->draw->window, ginfo->draw->style->mid_gc[3],
+                      x, 0, x, ginfo->draw->allocation.width);
+}
+
 static void update_with_backend(struct graph_info *ginfo,
                                 gint x, gint y,
                                 gint width, gint height)
@@ -134,6 +149,10 @@ static void update_with_backend(struct graph_info *ginfo,
         gint cpu;
 
         __update_with_backend(ginfo, x, y, width, height);
+
+        if (ginfo->cursor)
+                draw_cursor(ginfo);
+
         for (cpu = 0; cpu < ginfo->cpus; cpu++ ) {
                 if (y <= CPU_BOTTOM(cpu) &&
                     y + height > CPU_TOP(cpu) &&
@@ -162,6 +181,17 @@ draw_line(GtkWidget *widget, gdouble x, struct graph_info *ginfo)
                       x, 0, x, widget->allocation.width);
 }
 
+static void clear_last_line(GtkWidget *widget, struct graph_info *ginfo)
+{
+        gint x;
+
+        x = ginfo->last_x;
+        if (x)
+                x--;
+
+        update_with_backend(ginfo, x, 0, x+2, widget->allocation.height);
+}
+
 static gboolean
 button_press_event(GtkWidget *widget, GdkEventButton *event, gpointer data)
 {
@@ -172,6 +202,29 @@ button_press_event(GtkWidget *widget, GdkEventButton *event, gpointer data)
         if (event->button != 1)
                 return TRUE;
 
+        /* check for double click */
+        if (event->type==GDK_2BUTTON_PRESS) {
+                if (ginfo->line_active) {
+                        ginfo->line_active = FALSE;
+                        clear_last_line(widget, ginfo);
+                        ginfo->last_x = ginfo->press_x;
+                        clear_last_line(widget, ginfo);
+                }
+                if (ginfo->cursor >= ginfo->view_start_time &&
+                    ginfo->cursor <= ginfo->view_end_time) {
+                        ginfo->last_x = (ginfo->cursor - ginfo->view_start_time)
+                                * ginfo->resolution;
+                        ginfo->cursor = 0;
+                        clear_last_line(widget, ginfo);
+                }
+
+                ginfo->cursor = event->x / ginfo->resolution +
+                        ginfo->view_start_time;
+                draw_cursor(ginfo);
+                return TRUE;
+        }
+
+
         ginfo->press_x = event->x;
         ginfo->last_x = 0;
 
@@ -182,17 +235,6 @@ button_press_event(GtkWidget *widget, GdkEventButton *event, gpointer data)
         return TRUE;
 }
 
-static void clear_last_line(GtkWidget *widget, struct graph_info *ginfo)
-{
-        gint x;
-
-        x = ginfo->last_x;
-        if (x)
-                x--;
-
-        update_with_backend(ginfo, x, 0, x+2, widget->allocation.height);
-}
-
 static void print_rec_info(struct record *record, struct pevent *pevent, int cpu)
 {
         struct trace_seq s;
diff --git a/trace-graph.h b/trace-graph.h
index 61f5546..dd5f58b 100644
--- a/trace-graph.h
+++ b/trace-graph.h
@@ -16,6 +16,8 @@ struct graph_info {
         guint64                 view_end_time;  /* visible end time */
         gint                    start_x;        /* virutal start of visible area */
 
+        guint64                 cursor;         /* time of cursor (double clicked) */
+
         gdouble                 resolution;     /* pixels / time */
 
         gint                    press_x;        /* x where button is pressed */