improved default NTSC custom palette

stella-emu · Dec 9, 2024 · 4bb07a9 · 4bb07a9
1 parent 8d5eb28
commit 4bb07a9
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Showing 2 changed files with 7 additions and 4 deletions.
diff --git a/src/common/PaletteHandler.cxx b/src/common/PaletteHandler.cxx
@@ -449,13 +449,15 @@ void PaletteHandler::generateCustomPalette(ConsoleTiming timing) const
 {
   constexpr int NUM_CHROMA = 16;
   constexpr int NUM_LUMA = 8;
-  constexpr float SATURATION = 0.25F; // default saturation
 
   if(timing == ConsoleTiming::ntsc)
   {
+    constexpr float SATURATION = 0.30F; // default NTSC saturation
     vector2d IQ[NUM_CHROMA];
-    // YIQ is YUV shifted by 33 degrees
-    constexpr float offset = 33 * BSPF::PI_f / 180;
+    // YIQ is YUV shifted by 33°
+    // -90° + 33° = -57° would create a greenish yellow
+    // -90° + 53° = -37° creates gold (which is correct according to the documentation)
+    constexpr float offset = (33 + 20) * BSPF::PI_f / 180;
     const float shift = myPhaseNTSC * BSPF::PI_f / 180;
 
     // color 0 is grayscale
@@ -496,6 +498,7 @@ void PaletteHandler::generateCustomPalette(ConsoleTiming timing) const
   }
   else if(timing == ConsoleTiming::pal)
   {
+    constexpr float SATURATION = 0.25F; // default PAL saturation
     constexpr float offset = BSPF::PI_f;
     const float shift = myPhasePAL * BSPF::PI_f / 180;
     constexpr float fixedShift = 22.5F * BSPF::PI_f / 180;

diff --git a/src/common/PaletteHandler.hxx b/src/common/PaletteHandler.hxx
@@ -33,7 +33,7 @@ class PaletteHandler
     static constexpr string_view SETTING_CUSTOM = "custom";
 
     // Phase shift default and limits
-    static constexpr float DEF_NTSC_SHIFT = 26.2F;
+    static constexpr float DEF_NTSC_SHIFT = 26.7F; // makes color $fx fall between $1x and $2x
     static constexpr float DEF_PAL_SHIFT = 31.3F; // ~= 360 / 11.5
     static constexpr float MAX_PHASE_SHIFT = 4.5F;
     static constexpr float DEF_RGB_SHIFT = 0.0F;