diff --git a/common/2d/bitmap.cpp b/common/2d/bitmap.cpp
index bd3bf7403..f51750ccb 100644
--- a/common/2d/bitmap.cpp
+++ b/common/2d/bitmap.cpp
@@ -36,6 +36,8 @@ COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
 #endif
 #include "bitmap.h"
 
+#include "compiler-make_unique.h"
+
 // Allocated a bitmap and makes its data be raw_data that is already somewhere.
 static grs_bitmap_ptr gr_create_bitmap_raw(uint16_t w, uint16_t h, unsigned char * raw_data);
 
@@ -56,7 +58,7 @@ grs_bitmap_ptr gr_create_bitmap(uint16_t w, uint16_t h )
 
 grs_bitmap_ptr gr_create_bitmap_raw(uint16_t w, uint16_t h, unsigned char * raw_data )
 {
-	grs_bitmap_ptr n(new grs_bitmap);
+	auto n = make_unique<grs_main_bitmap>();
 	gr_init_bitmap(*n.get(), 0, 0, 0, w, h, w, raw_data);
 	return n;
 }
@@ -97,16 +99,11 @@ void gr_init_bitmap_data (grs_bitmap &bm) // TODO: virtulize
 
 grs_subbitmap_ptr gr_create_sub_bitmap(grs_bitmap &bm, uint16_t x, uint16_t y, uint16_t w, uint16_t h)
 {
-	grs_subbitmap_ptr n(new grs_bitmap);
+	auto n = make_unique<grs_subbitmap>();
 	gr_init_sub_bitmap(*n.get(), bm, x, y, w, h);
 	return n;
 }
 
-void gr_free_bitmap(std::unique_ptr<grs_bitmap> bm)
-{
-	gr_free_bitmap_data(*bm.get());
-}
-
 void gr_free_bitmap_data (grs_bitmap &bm) // TODO: virtulize
 {
 #ifdef OGL
diff --git a/common/include/gr.h b/common/include/gr.h
index 5c8d06cfb..839ec8462 100644
--- a/common/include/gr.h
+++ b/common/include/gr.h
@@ -232,36 +232,37 @@ void gr_init_bitmap(grs_bitmap &bm, uint8_t mode, uint16_t x, uint16_t y, uint16
 void gr_init_sub_bitmap (grs_bitmap &bm, grs_bitmap &bmParent, uint16_t x, uint16_t y, uint16_t w, uint16_t h);
 
 void gr_init_bitmap_alloc(grs_bitmap &bm, uint8_t mode, uint16_t x, uint16_t y, uint16_t w, uint16_t h, uint16_t bytesperline);
+void gr_free_bitmap_data(grs_bitmap &bm);
 
 // Free the bitmap and its pixel data
-void gr_free_bitmap(std::unique_ptr<grs_bitmap> bm);
-
-struct bitmap_delete
+class grs_main_bitmap : public grs_bitmap
 {
-	void operator()(grs_bitmap *p) const
+public:
+	grs_main_bitmap() = default;
+	grs_main_bitmap(const grs_main_bitmap &) = delete;
+	grs_main_bitmap &operator=(const grs_main_bitmap &) = delete;
+	~grs_main_bitmap()
 	{
-		gr_free_bitmap(std::unique_ptr<grs_bitmap>(p));
+		gr_free_bitmap_data(*this);
 	}
 };
 
-typedef std::unique_ptr<grs_bitmap, bitmap_delete> grs_bitmap_ptr;
+typedef std::unique_ptr<grs_main_bitmap> grs_bitmap_ptr;
 
 // Allocate a bitmap and its pixel data buffer.
 grs_bitmap_ptr gr_create_bitmap(uint16_t w,uint16_t h);
 
 // Free the bitmap, but not the pixel data buffer
-struct subbitmap_delete : private std::default_delete<grs_bitmap>
+class grs_subbitmap : public grs_bitmap
 {
-	using default_delete<grs_bitmap>::operator();
 };
 
-typedef std::unique_ptr<grs_bitmap, subbitmap_delete> grs_subbitmap_ptr;
+typedef std::unique_ptr<grs_subbitmap> grs_subbitmap_ptr;
 
 // Creates a bitmap which is part of another bitmap
 grs_subbitmap_ptr gr_create_sub_bitmap(grs_bitmap &bm, uint16_t x, uint16_t y, uint16_t w, uint16_t h);
 
 // Free the bitmap's data
-void gr_free_bitmap_data (grs_bitmap &bm);
 void gr_init_bitmap_data (grs_bitmap &bm);
 
 void gr_bm_pixel(grs_bitmap &bm, uint_fast32_t x, uint_fast32_t y, uint8_t color );