New APIs: GetWindowSurfaceBufferFD() and CreateMemDCFromSurfaceBufferFD() for compositing schema.

RELEASE-NOTES.md

@@ -1,5 +1,7 @@
 # Release Notes
 
+- [Version 5.2.0](#version-520)
+   + [What's new in version 5.2.0](#whats-new-in-version-520)
 - [Version 5.0.13](#version-5013)
    + [What's new in version 5.0.13](#whats-new-in-version-5013)
 - [Version 5.0.12](#version-5012)
@@ -32,6 +34,17 @@
    + [Changes leading to incompatibility](#changes-leading-to-incompatibility)
    + [Deprecated APIs](#deprecated-apis)
 
+## Version 5.2.0
+
+On Nov. 30, 2023, FMSoft announces the availability of MiniGUI 5.2.0,
+which is an mainline release with some major enhancements:
+
+* ENHANCEMENTS:
+   - Optimize NEWGAL engines: `shadow`, `drm`, and `fbcon` for large resolution.
+   - New APIs: `GetWindowSurfaceBufferFD()` and `CreateMemDCFromSurfaceBufferFD()` for compositing schema.
+* CHANGES:
+   - The operations for DRM userland driver changed.
+
 ## Version 5.0.13
 
 On Aug. 31, 2023, FMSoft announces the availability of MiniGUI 5.0.13,

include/gdi.h

@@ -1704,6 +1704,27 @@ MG_EXPORT BOOL GUIAPI IsScreenDC (HDC hdc);
  */
 MG_EXPORT BOOL GUIAPI IsWindowDC (HDC hdc);
 
+#ifdef _MGSCHEMA_COMPOSITING
+/**
+ * \fn HDC GUIAPI CreateMemDCFromSurfaceBufferFD (int fd);
+ * \brief Creates a memory DC from a file descriptor of a surface buffer.
+ *
+ * This function creates a memory DC from the specified file descriptor \a fd,
+ * which represents a surface buffer.
+ *
+ * \param fd The file descriptor which represents a surface buffer.
+ *
+ * \return The handle to a new memory DC, HDC_INVALID indicates an error.
+ *
+ * \note This function only available when _MGSCHEMA_COMPOSITING is defined.
+ *
+ * \sa GetWindowSurfaceBufferFD
+ *
+ * Since 5.0.13
+ */
+MG_EXPORT HDC GUIAPI CreateMemDCFromSurfaceBufferFD (int fd);
+#endif /* _MGSCHEMA_COMPOSITING */
+
 /**
  * \fn HDC GUIAPI CreateMemDCEx (int width, int height, int depth, DWORD flags, \
  Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask,

include/window.h

@@ -7237,6 +7237,29 @@ MG_EXPORT BOOL GUIAPI SetMainWindowGestureFlags (HWND hWnd, DWORD dwFlags);
 
 #ifdef _MGSCHEMA_COMPOSITING
 
+/**
+ * \fn int GUIAPI GetWindowSurfaceBufferFD (HWND hwnd)
+ * \brief Gets the file descriptor of the surface buffer for a window or
+ * the main window it locates.
+ *
+ * This function gets the file descriptor of the surface buffer for
+ * the specified window if it is a main window or the main window it locates.
+ * Note that if the window is a control that has the style `WS_EX_CTRLASMAINWIN`,
+ * the window will have a separate surface buffer.
+ *
+ * \param hwnd The handle to the window.
+ *
+ * \return An integer larger than or equal to 0 for a valid file descriptor,
+ *      otherwise a negative value.
+ *
+ * \note This function only available when _MGSCHEMA_COMPOSITING is defined.
+ *
+ * \sa CreateMemDCFromSurfaceBufferFD
+ *
+ * Since 5.0.13
+ */
+MG_EXPORT int GUIAPI GetWindowSurfaceBufferFD (HWND hWnd);
+
 /**
  * \fn BOOL GUIAPI SetMainWindowCompositing (HWND hWnd,
         int type, DWORD arg)

src/gui/window.c

@@ -6066,6 +6066,19 @@ error:
     return HWND_INVALID;
 }
 
+#ifdef _MGSCHEMA_COMPOSITING
+int GUIAPI GetWindowSurfaceBufferFD (HWND hWnd)
+{
+    MG_CHECK_RET (MG_IS_APP_WINDOW (hWnd), -1);
+
+    PMAINWIN pWin = (PMAINWIN)hWnd;
+    if (pWin->surf->shared_header)
+        return pWin->surf->shared_header->fd;
+
+    return -1;
+}
+#endif /* _MGSCHEMA_COMPOSITING */
+
 BOOL GUIAPI DestroyWindow (HWND hWnd)
 {
     PCONTROL pCtrl;

src/newgdi/gdi.c

@@ -3391,6 +3391,29 @@ struct GAL_Surface* GetSurfaceFromDC (HDC hdc)
     return pdc->surface;
 }
 
+#ifdef _MGSCHEMA_COMPOSITING
+HDC GUIAPI CreateMemDCFromSurfaceBufferFD (int fd)
+{
+    HDC memdc = HDC_INVALID;
+    GAL_Surface* surf;
+
+    surf = GAL_AttachSharedRGBSurface (fd, 0, GAL_HWSURFACE, TRUE);
+    if (surf) {
+        memdc = CreateMemDCFromSurface (surf);
+        if (memdc == HDC_INVALID) {
+            GAL_FreeSurface(surf);
+
+            _ERR_PRINTF("failed to create memory dc from surface: %p\n", surf);
+        }
+    }
+    else {
+        _ERR_PRINTF("failed to attach to surface buffer via fd: %d\n", fd);
+    }
+
+    return memdc;
+}
+#endif /* _MGSCHEMA_COMPOSITING */
+
 HDC GUIAPI CreateSubMemDC (HDC parent, int off_x, int off_y,
                 int width, int height, BOOL comp_to_parent)
 {