[win32] Disable automatic thumbnail squaring for everything except IE…

…xtractIcon.

It seems this causes cover art for e.g. Wii U and PS2 to be squished.
I'm pretty sure it worked before, though...

The Win32 CreateThumbnail class now takes a parameter, doSquaring.
It's set to false by default, but RP_ExtractIcon sets it to true.
CreateThumbnail::rpImageToImgClass() will only square the image if
the doSquaring parameter was set to true in the constructor.

CreateThumbnailNoAlpha also has the parameter, though since this class
is only used by RP_ExtractImage, it will stay false.

Fixes #385: Ratio of ps2 longbox thumbnails looks wrong?
Reported by @Masamune3210.

NEWS.md

@@ -18,6 +18,9 @@
     * This was broken in v2.2.
     * Fixes #389: Gamecube Property sheet is blank
       * Reported by @Masamune3210.
+  * Windows: Don't square thumbnails for anything except icon extraction.
+    * Fixes #385: Ratio of ps2 longbox thumbnails looks wrong?
+      * Reported by @Masamune3210.
 
 ## v2.2 (released 2023/07/01)
 

src/win32/CreateThumbnail.cpp

@@ -2,7 +2,7 @@
  * ROM Properties Page shell extension. (Win32)                            *
  * CreateThumbnail.cpp: TCreateThumbnail<HBITMAP> implementation.          *
  *                                                                         *
- * Copyright (c) 2016-2022 by David Korth.                                 *
+ * Copyright (c) 2016-2023 by David Korth.                                 *
  * SPDX-License-Identifier: GPL-2.0-or-later                               *
  ***************************************************************************/
 
@@ -51,9 +51,8 @@ HBITMAP CreateThumbnail::rpImageToImgClass(const rp_image *img) const
 	// Windows doesn't like non-square icons.
 	// Add extra transparent columns/rows before
 	// converting to HBITMAP.
-	// TODO: Disable this for RP_ExtractImage and RP_ThumbnailProvider?
 	rp_image *tmp_img = nullptr;
-	if (!img->isSquare()) {
+	if (m_doSquaring && !img->isSquare()) {
 		// Image is non-square.
 		tmp_img = img->squared();
 		assert(tmp_img != nullptr);

src/win32/CreateThumbnail.hpp

@@ -18,7 +18,10 @@
 class CreateThumbnail : public LibRomData::TCreateThumbnail<HBITMAP>
 {
 	public:
-		explicit CreateThumbnail() = default;
+		explicit CreateThumbnail(bool doSquaring = false)
+		{
+			m_doSquaring = doSquaring;
+		}
 
 	private:
 		typedef TCreateThumbnail<HBITMAP> super;
@@ -102,6 +105,14 @@ class CreateThumbnail : public LibRomData::TCreateThumbnail<HBITMAP>
 		 * @return True if metered; false if not.
 		 */
 		bool isMetered(void) final;
+
+	private:
+		// Enable automatic squaring of thumbnails when converting to the
+		// native OS image class. This is needed for icons.
+		// - IExtractIcon: squared
+		// - IExtractImage: not squared
+		// - IThumbnailProvider: not squared
+		bool m_doSquaring;
 };
 
 /**
@@ -112,7 +123,9 @@ class CreateThumbnail : public LibRomData::TCreateThumbnail<HBITMAP>
 class CreateThumbnailNoAlpha final : public CreateThumbnail
 {
 	public:
-		explicit CreateThumbnailNoAlpha() = default;
+		explicit CreateThumbnailNoAlpha(bool doSquaring = false)
+			: super(doSquaring)
+		{ }
 
 	private:
 		typedef CreateThumbnail super;

src/win32/RP_ExtractIcon.cpp

@@ -30,6 +30,7 @@ const CLSID CLSID_RP_ExtractIcon =
 RP_ExtractIcon_Private::RP_ExtractIcon_Private()
 	: filename(nullptr)
 	, romData(nullptr)
+	, thumbnailer(true)	// enable automatic squaring
 { }
 
 RP_ExtractIcon_Private::~RP_ExtractIcon_Private()