Native retina support.

.vscode/settings.json

@@ -28,6 +28,71 @@
         "__cxx_version": "cpp",
         "string": "cpp",
         "type_traits": "cpp",
-        "ostream": "cpp"
+        "ostream": "cpp",
+        "__bit_reference": "cpp",
+        "__config": "cpp",
+        "__debug": "cpp",
+        "__errc": "cpp",
+        "__hash_table": "cpp",
+        "__locale": "cpp",
+        "__mutex_base": "cpp",
+        "__node_handle": "cpp",
+        "__nullptr": "cpp",
+        "__split_buffer": "cpp",
+        "__string": "cpp",
+        "__threading_support": "cpp",
+        "__tree": "cpp",
+        "__tuple": "cpp",
+        "algorithm": "cpp",
+        "atomic": "cpp",
+        "bit": "cpp",
+        "bitset": "cpp",
+        "cctype": "cpp",
+        "chrono": "cpp",
+        "clocale": "cpp",
+        "cmath": "cpp",
+        "codecvt": "cpp",
+        "complex": "cpp",
+        "condition_variable": "cpp",
+        "cstdarg": "cpp",
+        "cstddef": "cpp",
+        "cstdint": "cpp",
+        "cstdio": "cpp",
+        "cstdlib": "cpp",
+        "cstring": "cpp",
+        "ctime": "cpp",
+        "cwchar": "cpp",
+        "cwctype": "cpp",
+        "deque": "cpp",
+        "exception": "cpp",
+        "fstream": "cpp",
+        "initializer_list": "cpp",
+        "ios": "cpp",
+        "iosfwd": "cpp",
+        "iostream": "cpp",
+        "iterator": "cpp",
+        "limits": "cpp",
+        "list": "cpp",
+        "map": "cpp",
+        "mutex": "cpp",
+        "new": "cpp",
+        "numeric": "cpp",
+        "optional": "cpp",
+        "queue": "cpp",
+        "random": "cpp",
+        "ratio": "cpp",
+        "set": "cpp",
+        "sstream": "cpp",
+        "stack": "cpp",
+        "stdexcept": "cpp",
+        "streambuf": "cpp",
+        "string_view": "cpp",
+        "system_error": "cpp",
+        "typeinfo": "cpp",
+        "unordered_map": "cpp",
+        "vector": "cpp",
+        "memory_resource": "cpp",
+        "cfenv": "cpp",
+        "cinttypes": "cpp"
     }
 }

src/common/FrameBufferSDL2.cxx

@@ -33,7 +33,9 @@ FrameBufferSDL2::FrameBufferSDL2(OSystem& osystem)
     myWindow(nullptr),
     myRenderer(nullptr),
     myCenter(false),
-    myRenderTargetSupport(false)
+    myRenderTargetSupport(false),
+    myScaleX(1),
+    myScaleY(1)
 {
   ASSERT_MAIN_THREAD;
 
@@ -263,6 +265,7 @@ bool FrameBufferSDL2::setVideoMode(const string& title, const VideoMode& mode)
     posY = BSPF::clamp(posY, y0 + 50, y1 - 50);
   }
   uInt32 flags = mode.fsIndex != -1 ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0;
+  flags |= SDL_WINDOW_ALLOW_HIGHDPI;
 
   // macOS seems to have issues with destroying the window, and wants to
   // keep the same handle
@@ -321,7 +324,9 @@ bool FrameBufferSDL2::setVideoMode(const string& title, const VideoMode& mode)
     SDL_SetHint(SDL_HINT_RENDER_DRIVER, video.c_str());
 
   myRenderer = SDL_CreateRenderer(myWindow, -1, renderFlags);
+
   detectFeatures();
+  calculateScaleFactors();
 
   if(myRenderer == nullptr)
   {
@@ -513,3 +518,30 @@ bool FrameBufferSDL2::hasRenderTargetSupport() const
 {
   return myRenderTargetSupport;
 }
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FrameBufferSDL2::calculateScaleFactors()
+{
+  if (myRenderer == nullptr) {
+    myScaleX = myScaleY = 1;
+    return;
+  }
+
+  int windowW, windowH, renderW, renderH;
+
+  SDL_GetWindowSize(myWindow, &windowW, &windowH);
+  SDL_GetRendererOutputSize(myRenderer, &renderW, &renderH);
+
+  myScaleX = renderW / windowW;
+  myScaleY = renderH / windowH;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt8 FrameBufferSDL2::scaleX() const {
+  return myScaleX;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt8 FrameBufferSDL2::scaleY() const {
+  return myScaleY;
+}

src/common/FrameBufferSDL2.hxx

@@ -134,6 +134,16 @@ class FrameBufferSDL2 : public FrameBuffer
      */
     bool hasRenderTargetSupport() const;
 
+    /**
+      Retina scale factor, x direction;
+     */
+    uInt8 scaleX() const;
+
+    /**
+      Retina scale Factor, y direction;
+     */
+    uInt8 scaleY() const;
+
   protected:
     //////////////////////////////////////////////////////////////////////
     // The following are derived from protected methods in FrameBuffer.hxx
@@ -208,6 +218,8 @@ class FrameBufferSDL2 : public FrameBuffer
      */
     bool detectRenderTargetSupport();
 
+    void calculateScaleFactors();
+
   private:
     // The SDL video buffer
     SDL_Window* myWindow;
@@ -222,8 +234,12 @@ class FrameBufferSDL2 : public FrameBuffer
     // last position of windowed window
     Common::Point myWindowedPos;
 
+    // Does the renderer support render targets?
     bool myRenderTargetSupport;
 
+    // Retina scale factors
+    uInt32 myScaleX, myScaleY;
+
   private:
     // Following constructors and assignment operators not supported
     FrameBufferSDL2() = delete;

src/common/sdl_blitter/BilinearBlitter.cxx

@@ -57,6 +57,11 @@ void BilinearBlitter::reinitialize(
    mySrcRect = srcRect;
    myDstRect = destRect;
    myAttributes = attributes;
+
+   myDstRect.x *= myFB.scaleX();
+   myDstRect.y *= myFB.scaleY();
+   myDstRect.w *= myFB.scaleX();
+   myDstRect.h *= myFB.scaleY();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/common/sdl_blitter/QisBlitter.cxx

@@ -65,6 +65,11 @@ void QisBlitter::reinitialize(
    mySrcRect = srcRect;
    myDstRect = destRect;
    myAttributes = attributes;
+
+   myDstRect.x *= myFB.scaleX();
+   myDstRect.y *= myFB.scaleY();
+   myDstRect.w *= myFB.scaleX();
+   myDstRect.h *= myFB.scaleY();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -