Use a fast auto-commit delay for keyboard arrow-key edits

Nudging Disparity Shift/Threshold with Left/Right, or changing
Downscale Ratio via keyboard/gamepad navigation, now schedules the
commit 0.1s out instead of the usual 1.7s - keyboard-driven edits
already land at a known, deliberate value one step at a time, so
there's no need for the same give-me-a-moment-to-change-my-mind pause
a mouse drag gets; a mouse click on the same radio buttons still uses
the full 1.7s.

finalize() takes an optional use_fast_delay flag for this. The radio
buttons distinguish the two input methods via IsMouseClicked(), since
RadioButton() itself returns true for both a mouse click and a
keyboard/gamepad nav selection change; the slider arrow-key branches
are unambiguous (mouse dragging is a separate code path) and always
pass true.

Author: Evgeni Raikhel

common/composite-control-editor.h

@@ -107,10 +107,14 @@ namespace rs2
         }
 
         // Call once a field's edit is finalized (slider released, or immediately after a
-        // checkbox/radio click). Schedules the real auto-commit commit_delay seconds out.
-        void finalize()
+        // checkbox/radio click). Schedules the auto-commit out by commit_delay seconds, or by
+        // the much shorter fast_commit_delay when use_fast_delay is set - the caller's own way
+        // of saying "this particular edit came from a keyboard arrow-key nudge, not a mouse
+        // click/drag," which should feel closer to immediate feedback than the deliberate,
+        // give-me-a-moment-to-change-my-mind pause a mouse edit gets.
+        void finalize( bool use_fast_delay = false )
         {
-            _commit_deadline = ImGui::GetTime() + commit_delay;
+            _commit_deadline = ImGui::GetTime() + ( use_fast_delay ? fast_commit_delay : commit_delay );
             // A discrete edit (radio/checkbox click, keyboard arrow-key nudge) calls touch()+
             // finalize() together, synchronously, within the SAME frame as the
             // end_frame_and_maybe_commit() call below that just set this deadline - unlike a
@@ -228,6 +232,7 @@ namespace rs2
         bool _just_finalized = false;
 
         static constexpr double commit_delay = 1.7;          // seconds of quiet before auto-sending
+        static constexpr double fast_commit_delay = 0.1;     // ditto, for keyboard arrow-key nudges
         static constexpr float border_start_scale = 4.0f;    // 400% of normal width, right after an edit
         static constexpr float border_end_scale = 2.5f;      // 250% of normal width, right before commit
     };

common/embedded-filter-model.cpp

@@ -168,7 +168,12 @@ namespace rs2
             {
                 _minz_editor.value.downscale_ratio = v;
                 _minz_editor.touch();
-                _minz_editor.finalize();   // one click = started and finished at once
+                // A mouse click lands on this exact frame as IsMouseClicked(); a keyboard/
+                // gamepad nav selection change reaches this same "pressed" return without one,
+                // since nothing was physically clicked - use the fast delay there so arrow-key
+                // navigation feels responsive instead of waiting out the same 1.7s a deliberate
+                // mouse click gets.
+                _minz_editor.finalize( ! ImGui::IsMouseClicked( ImGuiMouseButton_Left ) );
             }
             any_field_active = any_field_active || ImGui::IsItemActive();
         }
@@ -262,13 +267,13 @@ namespace rs2
                 {
                     _minz_editor.value.disparity_shift = std::min( _minz_editor.value.disparity_shift + 1, 512 );
                     _minz_editor.touch();
-                    _minz_editor.finalize();
+                    _minz_editor.finalize( true );   // arrow-key nudge - fast turnaround
                 }
                 else if( ImGui::IsKeyPressed( ImGuiKey_LeftArrow ) )
                 {
                     _minz_editor.value.disparity_shift = std::max( _minz_editor.value.disparity_shift - 1, 0 );
                     _minz_editor.touch();
-                    _minz_editor.finalize();
+                    _minz_editor.finalize( true );   // arrow-key nudge - fast turnaround
                 }
             }
             any_field_active = any_field_active || ImGui::IsItemActive();
@@ -343,13 +348,13 @@ namespace rs2
                 {
                     _minz_editor.value.threshold = std::min( _minz_editor.value.threshold + 1, 65535 );
                     _minz_editor.touch();
-                    _minz_editor.finalize();
+                    _minz_editor.finalize( true );   // arrow-key nudge - fast turnaround
                 }
                 else if( ImGui::IsKeyPressed( ImGuiKey_LeftArrow ) )
                 {
                     _minz_editor.value.threshold = std::max( _minz_editor.value.threshold - 1, 0 );
                     _minz_editor.touch();
-                    _minz_editor.finalize();
+                    _minz_editor.finalize( true );   // arrow-key nudge - fast turnaround
                 }
             }
             any_field_active = any_field_active || ImGui::IsItemActive();