--- a/tools/lib64gfx.h	Mon May 14 04:11:45 2018 +0300
+++ b/tools/lib64gfx.h	Mon May 14 04:27:53 2018 +0300
@@ -98,6 +98,13 @@
 };
 
 
+typedef struct
+{
+    Uint8 *data;
+    size_t size;
+} DMC64MemBlock;
+
+
 typedef struct _DMC64Image
 {
     int type,       // Image type (D64_FMT_*)
@@ -107,20 +114,20 @@
     int width, height; // Width and height in pixels
     int chWidth, chHeight; // Width and height in charblocks
 
-    size_t
-        screenSize,
-        bitmapSize,
-        charmemSize;
+    // Bitmaps, color RAM, screen, etc. blocks * nbanks
+    // Not all of them may be allocated
+    DMC64MemBlock
+        *color,
+        *bitmap,
+        *screen,
+        *charData;
 
-    Uint8
-        **color,
-        **bitmap,
-        **screen,
-        **charmem,
-        *extraData[C64_MAX_EXTRA_DATA],
-        d020, bgcolor, d022, d023, d024;
+    // Other standard colours
+    Uint8 d020, bgcolor, d022, d023, d024;
 
-    size_t extraDataSizes[C64_MAX_EXTRA_DATA];
+    // Extra data areas used by some formats,
+    // for example raster colours might be stored
+    DMC64MemBlock extraData[C64_MAX_EXTRA_DATA];
 
     DMC64Sprite sprites[C64_MAX_SPRITES];
 } DMC64Image;
@@ -217,14 +224,20 @@
 // Miscellaneous functions
 //
 void      dmC64ImageDump(FILE *fh, const DMC64Image *img, const DMC64ImageFormat *fmt);
+char *    dmC64GetImageTypeString(char *buf, const size_t len, const int type, const BOOL lng);
+
 void      dmSetDefaultC64Palette(DMImage *img);
-char *    dmC64GetImageTypeString(char *buf, const size_t len, const int type, const BOOL lng);
+int       dmC64ImageGetNumBanks(const DMC64ImageFormat *fmt);
 int       dmC64ConvertCSDataToImage(DMImage *img, int xoffs, int yoffs, const Uint8 *inBuf, int width, int height, BOOL multicolor, int *colors);
-int       dmC64ImageGetNumBanks(const DMC64ImageFormat *fmt);
 BOOL      dmCompareAddr16(const Uint8 *buf, const size_t offs, const Uint16 addr);
+
 int       dmC64SanityCheckEncDecOp(const int i, const DMC64EncDecOp *op, const DMC64Image *img);
 BOOL      dmC64GetOpSize(const DMC64EncDecOp *op, const DMC64ImageFormat *fmt, size_t *size);
 
+int       dmC64MemBlockAlloc(DMC64MemBlock *blk, const size_t size);
+int       dmC64MemBlockCopy(DMC64MemBlock *dst, const DMC64MemBlock *src);
+void      dmC64MemBlockFree(DMC64MemBlock *blk);
+
 
 // C64 bitmap image allocation/freeing
 DMC64Image *dmC64ImageAlloc(const DMC64ImageFormat *fmt);
@@ -263,10 +276,10 @@
     const int vshift, const int vbank, const int vbitmap, const int cbank)
 {
     (void) cbank;
-    if ((img->bitmap[vbitmap][bmoffs] >> vshift) & 1)
-        return img->screen[vbank][scroffs] >> 4;
+    if ((img->bitmap[vbitmap].data[bmoffs] >> vshift) & 1)
+        return img->screen[vbank].data[scroffs] >> 4;
     else
-        return img->screen[vbank][scroffs] & 15;
+        return img->screen[vbank].data[scroffs] & 15;
 }
 
 
@@ -275,12 +288,12 @@
     const int vshift, const int vbank, const int vbitmap, const int cbank,
     const int bgcolor)
 {
-    switch ((img->bitmap[vbitmap][bmoffs] >> vshift) & 3)
+    switch ((img->bitmap[vbitmap].data[bmoffs] >> vshift) & 3)
     {
         case  0: return bgcolor;
-        case  1: return img->screen[vbank][scroffs] >> 4;
-        case  2: return img->screen[vbank][scroffs] & 15;
-        default: return img->color[cbank][scroffs] & 15;
+        case  1: return img->screen[vbank].data[scroffs] >> 4;
+        case  2: return img->screen[vbank].data[scroffs] & 15;
+        default: return img->color[cbank].data[scroffs] & 15;
     }
 }