Dash: Add graphical control to save traj file

vmd/cv_dashboard/cv_dashboard.tcl

@@ -4,15 +4,17 @@
 # Usage (after installing):
 # package require cv_dashboard
 # cv_dashboard
+# or select the Extensions/Analysis menu item
 
 # Design principles:
 # - take advantage of colvars/VMD binding for maximum user interaction
 # - hide the colvars config text from user, instead expose colvar, names and values
 # - do not try to parse the colvars config (let the Colvars Module do it)
 #   to avoid coming up with an incompatible parser
 
-# This plugin only acts on the "top" molecule
-# which is most consistent for trajectory animation (determined by the frame number of mol)
+# Source file layout:
+# - this file contains utility functions and data structure, without GUI
+# - other files contain GUI elements
 
 # TODO Multiplot:
 # - properly calculate position of cursor in plot when not all the plot is visible (resized window)
@@ -954,7 +956,8 @@ Read the standard output (terminal) for details."
 }
 
 
-#  Create a scripted colvar that returns values from a precomputed trajectory
+# Create a scripted colvar that returns values from a precomputed trajectory
+# (internal utility function for load_cv_traj, hence not in the main namespace)
 
 proc create_traj_colvar { molid cv } {
 
@@ -1010,3 +1013,20 @@ proc create_traj_colvar { molid cv } {
   "
   cv config $configString
 }
+
+# Save trajectory of currently defined colvars to a file in the colvars.traj format
+
+proc ::cv_dashboard::save_traj_file { fileName } {
+
+  puts "Writing colvars trajectory to file $fileName"
+  set o [open $fileName w]
+  puts -nonewline $o [cv printframelabels]
+
+  set nf [molinfo top get numframes]
+  for {set f 0} {$f< $nf} {incr f} {
+    cv frame $f
+    cv update
+    puts -nonewline $o [cv printframe]
+  }
+  close $o
+}

vmd/cv_dashboard/cv_dashboard_main.tcl

@@ -33,9 +33,13 @@ proc ::cv_dashboard::createWindow {} {
     -row $gridrow -column 0 -pady 2 -padx 2 -sticky nsew
   grid [ttk::button $w.save -text "Save" -command ::cv_dashboard::save -padding "2 0 2 0"] \
     -row $gridrow -column 1 -pady 2 -padx 2 -sticky nsew
-  grid [ttk::button $w.reset -text "Reset" -command ::cv_dashboard::reset -padding "2 0 2 0"] \
+  grid [ttk::button $w.reset -text "⚠ Reset ⚠" -command ::cv_dashboard::reset -padding "2 0 2 0"] \
     -row $gridrow -column 2 -pady 2 -padx 2 -sticky nsew
 
+  incr gridrow
+  grid [ttk::button $w.save_traj -text "Save traj file" -command ::cv_dashboard::save_traj_dialog -padding "2 0 2 0"] \
+    -row $gridrow -column 0 -pady 2 -padx 2 -sticky nsew
+
   # Table of colvars
   ttk::treeview $w.cvtable -selectmode extended -show {headings tree} -height 8
   $w.cvtable configure -column val
@@ -516,7 +520,7 @@ https://colvars.github.io
 In [vmdinfo versionmsg]
 Running Tcl/Tk [info patchlevel]
 
-Jérôme Hénin (jerome.henin@ibpc.fr), Giacomo Fiorin ([email protected]) and the Colvars developers.
+Jérôme Hénin (jerome.henin@cnrs.fr), Giacomo Fiorin ([email protected]) and the Colvars developers.
 
 #Please cite the following references for features currently in use:
 
@@ -1488,3 +1492,13 @@ proc ::cv_dashboard::createRotationMenu { row } {
 
   grid remove $menu.show_rotation $menu.hide_rotation
 }
+
+# Open file dialog to choose file name, then save colvars trajectory
+
+proc ::cv_dashboard::save_traj_dialog {} {
+  set file [tk_getSaveFile -title "Colvars trajectory file to be written" \
+      -filetypes {{"Colvars traj" .colvars.traj} {"All files" *}}]
+  if {[llength $file] > 0 } {
+    ::cv_dashboard::save_traj_file $file
+  }
+}