feature custom snapshot_cmd implemented

[boecko]

This PR introduces 4 new timelapse-options .
It allows making timelapses via invocation of a custom shellscript.
In my case i'm using gphoto2 to control a Canon EOS70D camara.
It use_snapshot_cmd is False or snapshot_cmd_check fails, the normal configuration is used.

[timelapse]
    use_snapshot_cmd: True
    snapshot_cmd: /home/pi/bin/gphoto2_capture.sh
    snapshot_cmd_check: /home/pi/bin/gphoto2_check.sh
    snapshot_cmd_waittime: 10.0

[AYA-123]

Hi, how would you go about combining this with the gcode shell command?

[AYA-123]

I have these macros:

[gcode_macro TAKE_SNAPSHOT]
description: Saves current location, moves toolhead to rear of bed, and takes a snapshot before returning.
gcode:
  {% set delayMS = 2000 %} ; Delay after moving and before taking the snapshot, deals with buffering so we don't get the print head in motion
  {% set snapshotPositionX = printer.toolhead.axis_maximum.x / 2 %} ; Middle of bed
  {% set snapshotPositionY = printer.toolhead.axis_maximum.y - 5 %} ; rear of bed w/ some buffer
  {% set currentX = printer.gcode_move.gcode_position.x %}
  {% set currentY = printer.gcode_move.gcode_position.y %}
  {% set currentZ = printer.gcode_move.gcode_position.z %} ; could be used for z-hop which we are not doing in this macro, so it's best to run this in AFTER_LAYER_CHANGE
  {% set snapshotPositionZ = printer.gcode_move.gcode_position.z + 5 %}
  
  SAVE_GCODE_STATE NAME=take_snapshot_state

  {% if printer.extruder.can_extrude|lower == 'true' %}
    G10 ; retract
  {% endif %}

  G90

  G0 X{snapshotPositionX} Y{snapshotPositionY} Z{snapshotPositionZ} F5000.0 ;Move to snapshot position

  G4 P{delayMS} ; Dwell for delayMS seconds

  RUN_SHELL_COMMAND CMD=gphoto2_trigger_snapshot

  G0 X{currentX} Y{currentY} Z {currentZ} F5000.0 ;Return to original position

  {% if printer.extruder.can_extrude|lower == 'true' %}
    G11 ; unretract
  {% endif %}

  RESTORE_GCODE_STATE NAME=take_snapshot_state



[gcode_macro GPHOTO_SNAPSHOT_TEST]
gcode:
  RUN_SHELL_COMMAND CMD=gphoto_trigger

Along with this shell command cfg file:

#=====================================================
# SET CAMERA SAVE LOCATION
#=====================================================
[gcode_shell_command gphoto2_set_config]
command: gphoto2 --set-config capturetarget=1
timeout: 1. ; make sure this is long enough to account for focus time
verbose: False

#=====================================================
# DSLR CAPTURE IMAGE
#=====================================================
[gcode_shell_command gphoto2_trigger_snapshot]
command: gphoto2 --auto-detect --trigger-capture
timeout: 10. ; make sure this is long enough to account for focus time
verbose: False

And I'm using TAKE_SNAPSHOT in my slicer after every line. I saw in #155 to do:

[timelapse]
use_gphoto2=True

But you have to download the .sh files to your pi for that - it would be much simpler to use the cfg files, so is this possible?