Support applying Hue/Saturation filter in selected palette entries

src/app/commands/filters/filter_manager_impl.cpp

@@ -20,7 +20,9 @@
 #include "app/modules/editors.h"
 #include "app/modules/palettes.h"
 #include "app/transaction.h"
+#include "app/ui/color_bar.h"
 #include "app/ui/editor/editor.h"
+#include "app/ui/palette_view.h"
 #include "doc/algorithm/shrink_bounds.h"
 #include "doc/cel.h"
 #include "doc/image.h"
@@ -360,6 +362,17 @@ Palette* FilterManagerImpl::getNewPalette()
   return m_site.sprite()->palette(m_site.frame());
 }
 
+doc::PalettePicks FilterManagerImpl::getPalettePicks()
+{
+  doc::PalettePicks picks;
+  ColorBar::instance()
+    ->getPaletteView()
+    ->getSelectedEntries(picks);
+  if (picks.picks() == 0)
+    picks.all();
+  return picks;
+}
+
 void FilterManagerImpl::init(Cel* cel)
 {
   ASSERT(cel);

src/app/commands/filters/filter_manager_impl.h

@@ -109,6 +109,7 @@ namespace app {
     const doc::Palette* getPalette() const override;
     const doc::RgbMap* getRgbMap() const override;
     doc::Palette* getNewPalette() override;
+    doc::PalettePicks getPalettePicks() override;
 
   private:
     void init(doc::Cel* cel);

src/filters/filter_indexed_data.h

@@ -10,6 +10,7 @@
 
 namespace doc {
   class Palette;
+  class PalettePicks;
   class RgbMap;
 }
 
@@ -26,6 +27,10 @@ namespace filters {
     // If a filter ask for a new palette, it means that the filter
     // will modify the palette instead of pixels.
     virtual doc::Palette* getNewPalette() = 0;
+
+    // Get the selected palettes to be modified by a palette filter
+    // (e.g. HueSaturationFilter).
+    virtual doc::PalettePicks getPalettePicks() = 0;
   };
 
 } // namespace filters

src/filters/hue_saturation_filter.cpp

@@ -12,6 +12,7 @@
 
 #include "doc/image.h"
 #include "doc/palette.h"
+#include "doc/palette_picks.h"
 #include "doc/rgbmap.h"
 #include "filters/filter_indexed_data.h"
 #include "filters/filter_manager.h"
@@ -154,11 +155,19 @@ void HueSaturationFilter::applyToIndexed(FilterManager* filterMgr)
   if (!filterMgr->isFirstRow())
     return;
 
-  const Palette* pal = filterMgr->getIndexedData()->getPalette();
+  FilterIndexedData* fid = filterMgr->getIndexedData();
   const Target target = filterMgr->getTarget();
-  Palette* newPal = filterMgr->getIndexedData()->getNewPalette();
+  const Palette* pal = fid->getPalette();
+  PalettePicks picks = fid->getPalettePicks();
+  Palette* newPal = fid->getNewPalette();
+
+  int i = 0;
+  for (bool state : picks) {
+    if (!state) {
+      ++i;
+      continue;
+    }
 
-  for (int i=0; i<newPal->size(); ++i) {
     color_t c = pal->getEntry(i);
     int r = rgba_getr(c);
     int g = rgba_getg(c);
@@ -197,6 +206,7 @@ void HueSaturationFilter::applyToIndexed(FilterManager* filterMgr)
     }
 
     newPal->setEntry(i, c);
+    ++i;
   }
 }