example slider mimic script for x-touch mini

examples/x-touch.lua

@@ -0,0 +1,150 @@
+--[[
+    This file is part of darktable,
+    copyright (c) 2023 Diederik ter Rahe
+
+    darktable is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    darktable is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with darktable.  If not, see <http://www.gnu.org/licenses/>.
+]]
+--[[
+X-Touch Mini flexible encoder shortcuts
+
+This script will create virtual sliders that are mapped dynamically to
+the most relevant sliders for the currently focused processing module.
+Tailored modules are color zones, tone equalizer, color calibration and
+mask manager properties. The script can easily be amended for other
+devices or personal preferences. Virtual "toggle" buttons can be created
+as well, that dynamically change meaning depending on current status.
+
+USAGE
+* require this script from your main lua file
+* restart darktable
+* create shortcuts for each of the encoders on the x-touch mini
+  to a virtual slider under lua/x-touch
+  or import the following shortcutsrc file in the shortcuts dialog/preferences tab:
+
+None;midi:CC1=lua/x-touch/knob 1
+None;midi:CC2=lua/x-touch/knob 2
+None;midi:CC3=lua/x-touch/knob 3
+None;midi:CC4=lua/x-touch/knob 4
+None;midi:CC5=lua/x-touch/knob 5
+None;midi:CC6=lua/x-touch/knob 6
+None;midi:CC7=lua/x-touch/knob 7
+None;midi:CC8=lua/x-touch/knob 8
+midi:E0=global/modifiers
+midi:F0=global/modifiers;ctrl
+midi:F#0=global/modifiers;alt
+midi:G#-1=iop/blend/tools/show and edit mask elements
+midi:A-1=iop/colorzones;focus
+midi:A#-1=iop/toneequal;focus
+midi:B-1=iop/colorbalancergb;focus
+midi:C0=iop/channelmixerrgb;focus
+]]
+
+local dt = require "darktable"
+local du = require "lib/dtutils"
+
+du.check_min_api_version("9.1.0", "x-touch")
+
+-- set up 8 mimic sliders with the same function
+for k = 1,8 do
+  dt.gui.mimic("slider", "knob ".. k,
+    function(action, element, effect, size)
+      -- take the number from the mimic name
+      local k = tonumber(action:sub(-1))
+
+      -- only operate in darkroom; return NAN otherwise
+      if dt.gui.current_view() ~= dt.gui.views.darkroom then
+        return 0/0
+      end
+
+      local maskval = 0/0
+      if k < 8 then
+        -- first try if the mask slider at that position is active
+        local s = { "opacity",
+                    "size",
+                    "feather",
+                    "hardness",
+                    "rotation",
+                    "curvature",
+                    "compression" }
+        maskval = dt.gui.action("lib/masks/properties/" .. s[k], 
+                                element, effect, size)
+      end
+      -- if a value different from NAN is returned, the slider was active
+      if maskval == maskval then
+        return maskval
+
+      -- try if colorzones module is focused; if so select element of graph
+      elseif dt.gui.action("iop/colorzones", "focus") ~= 0 then
+        which = "iop/colorzones/graph"
+        local e = { "red",
+                    "orange",
+                    "yellow",
+                    "green",
+                    "aqua",
+                    "blue",
+                    "purple",
+                    "magenta" }
+        element = e[k]
+
+      -- if the tone equalizer is focused, 
+      -- select one of the sliders in the "simple" tab
+      elseif dt.gui.action("iop/toneequal", "focus") ~= 0 then
+        which ="iop/toneequal/simple/"..(k-9).." EV"
+
+      -- if color calibration is focused, 
+      -- the last 4 knobs are sent there
+      elseif dt.gui.action("iop/channelmixerrgb", "focus") ~= 0 
+             and k >= 5 then
+        -- knob 5 selects the active tab; pressing it resets to CAT
+        if k == 5 then
+          which = "iop/channelmixerrgb/page"
+          element = "CAT"
+          -- since the tab action is not a slider, 
+          -- the effects need to be translated
+          if     effect == "up"   then effect = "next"
+          elseif effect == "down" then effect = "previous"
+          else                         effect = "activate"
+          end
+        else
+          -- knobs 6, 7 and 8 are for the three color sliders on each tab
+          which = "iop/focus/sliders"
+          local e = { "1st",
+                      "2nd",
+                      "3rd" }
+          element = e[k - 5]
+        end
+
+      -- the 4th knob is contrast; 
+      -- either colorbalance if it is focused, or filmic
+      elseif dt.gui.action("iop/colorbalancergb", "focus") ~= 0 
+             and k == 4 then
+        which = "iop/colorbalancergb/contrast"
+
+      -- in all other cases use a default selection
+      else
+        local s = { "iop/exposure/exposure",
+                    "iop/filmicrgb/white relative exposure",
+                    "iop/filmicrgb/black relative exposure",
+                    "iop/filmicrgb/contrast",
+                    "iop/crop/left",
+                    "iop/crop/right",
+                    "iop/crop/top",
+                    "iop/crop/bottom" }
+        which = s[k]
+      end
+
+      -- now pass the element/effect/size to the selected slider
+      return dt.gui.action(which, element, effect, size)
+    end)
+end