A "monster" c struct to convert

[Legolas]

Ok, so... As usual, every new libnds release I get some problems converting it to pascal. This time a sprite related struct is changed and, when I saw the c source, my face looked like this one: :shock:
Ladies and Gentlemen, the scary "monster":

typedef union {
	struct {
		struct {
			u16 posY: 8;
			union {
				struct {
					u8: 1;
					bool isHidden: 1;
					u8: 6;
				};
				struct {
					bool isRotoscale: 1;
					bool rsDouble: 1;
					tObjMode objMode: 2;
					bool isMosaic: 1;
					tObjColMode colMode: 1;
					tObjShape objShape: 2;
				};
			};
		};
 
		union {
			struct {
				u16 posX: 9;
				u8: 7;
			};
			struct {
				u8: 8;
				union {
					struct {
						u8: 4;
						bool hFlip: 1;
						bool vFlip: 1;
						u8: 2;
					};
					struct {
						u8: 1;
						u8 rsMatrixIdx: 5; 
						tObjSize objSize: 2;
					};
				};
			};
		};
 
		struct {
			u16 tileIdx: 10;
			tObjPriority objPriority: 2;
			u8 objPal: 4;
		};

		u16 attribute3;
	};
 
	struct {
		uint16 attribute[3];
		uint16 filler;
	};
 
} SpriteEntry, * pSpriteEntry;

The main thing that drives me nuts is the fact that neither structs nor unions have a name, as some bit fields too. I could try to break this big nested struct in something smaller (and more readable), but I don't know how this change will be internally "digested" by the library.

[arthurprs]

they are anonymous unions, but no idea how to convert them to pascal :?

[JernejL]

dump the data to a file, look with a hex editor and figure out what is what, then write a pascal one.

[Brainer]

Indeed, it's a very difficult structure to convert, yet I tried to do it. I'm very unsure about the speed and correctness of this code, but I thought you should take a look.
[pascal]
type
//: Only for tests!
U16 = Integer;
U8 = Integer;
tObjMode = Boolean;
tObjColMode = Boolean;
tObjColShape = Double;
tObjShape = Boolean;
tObjSize = Single;
tObjPriority = Byte;
uint16 = LongInt;

{ .: StructA :. }
StructA = record
case Integer of
0: (A: u8);
1: (isHidden: Boolean);
2: (B: u8);
end;

{ .: StructB :. }
StructB = record
case Integer of
0: (isRotoscale: Boolean);
1: (rsDouble: Boolean);
2: (objMode: tObjMode);
3: (isMosaic: Boolean);
4: (colMode: tObjColMode);
5: (objShape: tObjColShape);
end;

{ .: StructC :. }
StructC = record
posX: u16;
A: u8;
end;

{ .: StructD :. }
StructD = record
A: u8;
hFlip: Boolean;
vFlip: Boolean;
B: u8;
end;

{ .: StructE :. }
StructE = record
A: u8;
rsMatrixIdx: u8;
objSize: tObjSize;
end;

{ .: StructF :. }
StructF = record
tileIdx: u16;
objPriority: tObjPriority;
objPal: u8;
end;

{ .: StructG :. }
StructG = record
attribute: array[0..2] of uint16;
filler: uint16;
end;

{ .: UnionA :. }
UnionA = record
posY: u16;
case Integer of
0: (A: StructA);
1: (B: StructB);
end;

{ .: UnionB :. }
UnionB = record
A: u8;
case Integer of
0: (B: StructD);
1: (C: StructE);
end;

{ .: UnionC :. }
UnionC = record
A: StructC;
B: UnionB;
end;

{ .: SpriteEntry :. }
pSpriteEntry = ^SpriteEntry;
SpriteEntry = record
attribute3: u16;
U1: UnionA;
U2: UnionB;
A: StructF;
B: StructG;
end;
[/pascal]

Hope that helps.

[JSoftware]

You can' convert it without placing labels on the unions. Using bitpacking you can get a quite good match

[arthurprs]

Post the result, i will like see how the struct is on pascal