Add option to enable SDL pixel art texture filter

Add a checkbox in display config to enable SDL_SCALEMODE_PIXELART when
it is available.

Signed-off-by: Rafael Kitover <rkitover@gmail.com>

cmake/Options.cmake

@@ -76,6 +76,14 @@ option(ENABLE_LZMA "Enable LZMA archive support" ON)
 if(ENABLE_SDL3)
    set(CMAKE_C_FLAGS "-DENABLE_SDL3 ${CMAKE_C_FLAGS}")
    set(CMAKE_CXX_FLAGS "-DENABLE_SDL3 ${CMAKE_CXX_FLAGS}")
+
+   include(CheckSymbolExists)
+   check_symbol_exists(SDL_SCALEMODE_PIXELART "SDL3/SDL.h" HAVE_SDL_SCALEMODE_PIXELART)
+
+   if(HAVE_SDL_SCALEMODE_PIXELART)
+      set(CMAKE_C_FLAGS "-DHAVE_SDL3_PIXELART ${CMAKE_C_FLAGS}")
+      set(CMAKE_CXX_FLAGS "-DHAVE_SDL3_PIXELART ${CMAKE_CXX_FLAGS}")
+   endif()
 endif()
 
 if(DISABLE_OPENGL)

src/wx/config/internal/option-internal.cpp

@@ -151,6 +151,7 @@ std::array<Option, kNbOptions>& Option::All() {
     struct OwnedOptions {
         /// Display
         bool bilinear = true;
+        bool sdl_pixel_art = false;
         Filter filter = Filter::kNone;
         wxString filter_plugin = wxEmptyString;
         Interframe interframe = Interframe::kNone;
@@ -280,6 +281,7 @@ std::array<Option, kNbOptions>& Option::All() {
     static std::array<Option, kNbOptions> g_all_opts = {
         /// Display
         Option(OptionID::kDispBilinear, &g_owned_opts.bilinear),
+        Option(OptionID::kDispSDLPixelArt, &g_owned_opts.sdl_pixel_art),
         Option(OptionID::kDispFilter, &g_owned_opts.filter),
         Option(OptionID::kDispFilterPlugin, &g_owned_opts.filter_plugin),
         Option(OptionID::kDispIFB, &g_owned_opts.interframe),
@@ -427,6 +429,7 @@ namespace internal {
 const std::array<OptionData, kNbOptions + 1> kAllOptionsData = {
     /// Display
     OptionData{"Display/Bilinear", "Bilinear", _("Use bilinear filter with 3d renderer")},
+    OptionData{"Display/SDLPixelArt", "SDLPixelArt", _("Use the SDL pixel art filter with an SDL renderer")},
     OptionData{"Display/Filter", "", _("Full-screen filter to apply")},
     OptionData{"Display/FilterPlugin", "", _("Filter plugin library")},
     OptionData{"Display/IFB", "", _("Interframe blending function")},

src/wx/config/option-id.h

@@ -8,6 +8,7 @@ namespace config {
 enum class OptionID {
     /// Display
     kDispBilinear = 0,
+    kDispSDLPixelArt,
     kDispFilter,
     kDispFilterPlugin,
     kDispIFB,

src/wx/config/option-proxy.h

@@ -12,6 +12,7 @@ namespace config {
 static constexpr std::array<Option::Type, kNbOptions> kOptionsTypes = {
     /// Display
     /*kDispBilinear*/ Option::Type::kBool,
+    /*kDispSDLPixelArt*/ Option::Type::kBool,
     /*kDispFilter*/ Option::Type::kFilter,
     /*kDispFilterPlugin*/ Option::Type::kString,
     /*kDispIFB*/ Option::Type::kInterframe,

src/wx/dialogs/display-config.cpp

@@ -386,6 +386,14 @@ DisplayConfig::DisplayConfig(wxWindow* parent)
     sdlrenderer_selector_ = GetValidatedChild<wxChoice>("SDLRenderer");
     sdlrenderer_selector_->SetValidator(SDLDevicesValidator());
 
+#if !defined(ENABLE_SDL3) || !defined(HAVE_SDL3_PIXELART)
+    GetValidatedChild<wxCheckBox>("SDLPixelArt")->Hide();
+#else
+    GetValidatedChild<wxCheckBox>("SDLPixelArt")
+        ->SetValidator(
+            widgets::OptionBoolValidator(config::OptionID::kDispSDLPixelArt));
+#endif
+
     wxWindow* color_profile_srgb = GetValidatedChild("ColorProfileSRGB");
     color_profile_srgb->SetValidator(
         ColorCorrectionProfileValidator(config::ColorCorrectionProfile::kSRGB));

src/wx/panel.cpp

@@ -2577,7 +2577,11 @@ SDL_TEXTUREACCESS_STREAMING, (width * scale), (height * scale));
 
 // Set bilinear or nearest on the texture.
 #ifdef ENABLE_SDL3
+#ifdef HAVE_SDL3_PIXELART
+    SDL_SetTextureScaleMode(texture, OPTION(kDispSDLPixelArt) ? SDL_SCALEMODE_PIXELART : OPTION(kDispBilinear) ? SDL_SCALEMODE_LINEAR : SDL_SCALEMODE_NEAREST);
+#else
     SDL_SetTextureScaleMode(texture, OPTION(kDispBilinear) ? SDL_SCALEMODE_LINEAR : SDL_SCALEMODE_NEAREST);
+#endif
 #else
     SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, OPTION(kDispBilinear) ? "1" : "0");
 #endif

src/wx/xrc/DisplayConfig.xrc

@@ -170,6 +170,13 @@
                 <flag>wxALL|wxEXPAND</flag>
                 <border>5</border>
               </object>
+              <object class="sizeritem">
+                <object class="wxCheckBox" name="SDLPixelArt">
+                  <label>SDL Pixel Art Filter</label>
+                </object>
+                <flag>wxALL|wxEXPAND</flag>
+                <border>5</border>
+              </object>
               <cols>2</cols>
               <growablecols>1</growablecols>
             </object>