Difference between revisions of "DAT file format"
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Revision as of 22:27, 12 August 2012
Contents
- 1 1. Preamble
- 2 2. Introduction
- 3 3. Primitives
- 4 4. DAT v1.0 Format Specifications
- 5 5. DAT v2.0 Format Specifications
- 6 6. PLV v1.0 Format Specifications
- 7 7. The SAV v1.0 format
- 8 8. The HOF v1.0 format
- 9 9. Credits
- 10 10. License
1. Preamble
This file was written thanks to the hard work on reverse engineering made by several people, see the credits section. In case you find any mistake in the text please report it. A copy of this document should be available in our official site at http://www.princed.org.
2. Introduction
There are two versions of the DAT file format: DAT v1.0 used in POP 1.x and DAT v2.0 used in POP 2. In this document we will specify DAT v1.0.
DAT files were made to store levels, images, palettes, wave, midi and internal speaker sounds. Each type has its own format as described below in the following sections.
As the format is very old and the original game was distributed in disks, it is normal to think that the file format uses some kind of checksum validation to detect file corruptions.
DAT files are indexed, this means that there is an index and you can access each resource through an ID that is unique for the resource inside the file.
Images store their height and width but not their palette, so the palette is another resource and must be shared by a group of images.
PLV files use the extension defined to support a format with only one level inside.
3. Primitives
This section shows how the PR dat handling primitives works, this library is useful to access resources without having to worry about the format. Here you can find the primitive chart of the dat.h library.
3.1. DAT reading and writing primitives
Opening a dat file for RW mode Syntax: int mRWBeginDatFile( const char* vFile, /* the name of the file to be open */ unsigned short int *numberOfItems, /* saves the total items count */ int optionflag /* see optionflag appendix */ ); Return values are:
int mRWCloseDatFile(dontSave);
3.2. DAT reading primitives
int mReadBeginDatFile(unsigned short int *numberOfItems,
const char* vFile);
int mReadFileInDatFile(int indexNumber,unsigned char** data,
unsigned long int *size);
int mReadInitResource(tResource** res,const unsigned char* data,
long size);
void mReadCloseDatFile();
3.3. DAT writing primitives
int mWriteBeginDatFile(const char* vFile, int optionflag);
void mWriteFileInDatFile(const unsigned char* data, int size);
void mWriteFileInDatFileIgnoreChecksum(unsigned char* data,int size);
void mWriteInitResource(tResource** res);
void mWriteCloseDatFile(tResource* r[],int dontSave,int optionflag, const
char* backupExtension);
4. DAT v1.0 Format Specifications
4.1. General file specs, index and checksums
All DAT files have an index, this index has a number of items count and a list of items. The index is stored at the very end of the file. The first 6 bytes are reserved to locate the index and know the file size.
Let's define the numbers as:
US - Unsigned Short: Little endian, 16 bits, storing two groups of 8 bits
ordered from the less representative to the most representative
without sign.
i.e. 65534 is FFFE in hex and is stored FE FF (1111 1110 1111 1111)
Range: 0 to 65535
2 bytes
UL - Unsigned long: Little endian, 32 bits, storing four groups of 8 bits
each ordered from the less representative to the most representative
without sign.
i.e. 65538 is 00010002 in hex and is stored 02 00 01 00
(0000 0010 0000 0000 0000 0001 0000 0000)
Range: 0 to 2^32-1
4 bytes
SC - Signed char: 8 bits, the first bit is for the sign and the 7 last
for the number. If the first bit is a 0, then the number is
positive, if not the number is negative, in that case invert all
bits and add 1 to get the positive number.
i.e. -1 is FF (1111 1111), 1 is 01 (0000 0001)
Range: -128 to 127
1 byte
UC - Unsigned char: 8 bits that represent the number.
i.e. 32 is 20 (0010 0000)
Range: 0 to 255
1 byte
Note: Sizes are allways in bytes unless another unit is specified.
Index structures:
The DAT header: Size = 6 bytes
- Offset 0, size 4, type UL: IndexOffset
(the location where the index begins)
- Offset 4, size 2, type US: IndexSize
(the number of bytes the index has)
Note that IndexSize is 8*numberOfItems+2
Note that IndexOffset+IndexSize=file size
The DAT index: Size = IndexSize bytes
- Offset IndexOffset, size 2, type US: NumberOfItems
(resources count)
- Offset IndexOffset+2, size NumberOfItems*8: The index
(a list of NumberOfItems blocks of 8-bytes-length index record)
The 8-bytes-length index record (one per item): Size = 8 bytes
- Relative offset 0, size 2, type US: Item ID
- Relative offset 2, size 4, type UL: Resource start
(absolute offset in file)
- Relative offset 6, size 2, type US: Size of the item
(not including the checksum byte)
Note: POP1 doesn't validate a DAT file checking: IndexOffset+IndexSize=FileSize this means you can append data at the end of the file.
PR validates that IndexOffset+IndexSize<=FileSize. It also compares IndexSize with 8*numberOfItems+2 to determine if a file is a valid POP1 DAT file.
Checksum byte: There is a checksum byte for each item (resource), this is the first byte of the item, the rest of the bytes are the item data. The item type is not stored and may only be determined by reading the data and applying some filters, unfortunately this method may fail. When you extract an item you should know what kind of item you are extracting.
If you add (sum) the whole item data including checksum and take the less representative byte (modulus 256) you will get the sum of the file. This sum must be FF in hex (255 in UC or -1 in SC). If the sum is not FF, then adjust the checksum in order to set this value to the sum. The best way to do that is adding all the bytes in the item data (excluding the checksum) and inverting all the bits. The resulting byte will be the right checksum.
From now on the specification are special for each data type (that means we won't include the checksum byte anymore).
4.2. Images
Images are stored compressed and have a header and a compressed data area. Each image only one header with 6 bytes in it as follows
4.2.1 Headers
The 6-bytes-image header: 6 bytes Relative offset 0, size 2, type US: Height Relative offset 2, size 2, type UL: Width Relative offset 4, size 2: Information
Information is a set of bits where: the first 8 are zeros the next 4 are the resolution: if it is 1011 (B in hex) then the image has 16 colours if it is 0000 (0 in hex) then the image has 2 colours so to calculate the bits per pixel there are in the image, just take the last 2 bits and add 1. e. g. 11 is 4 (2^4=16 colours) and 00 is 1 (2^1=2 colours). the last 4 bits are the 5 compression types: from 0 to 4: 0 RAW_LR (0000) 1 RLE_LR (0001) 2 RLE_UD (0010) 3 LZG_LR (0011) 4 LZG_UD (0100)
The following data in the resource is the image compressed with the algorithm specified by those 4 bits.
4.2.2 Algorithms
RAW_LR means that the data wasn't compressed, it is used for small images.
The format is saved from left to right (LR) serialising a line to
the next integer byte if necessary. In case the image was 16
colours, two pixels per byte (4bpp) will be used. In case the image
was 2 colours, 8 pixels per byte (1bpp) will be used.
RLE_LR has a Run length encoding (RLE) algorithm, after uncompressed the
image can be read as a RAW_LR.
RLE_UD is the same as RLE_LR except that after uncompressed the bytes in
the image must be drawn from up to down and then from left to right.
LZG_LR has some kind of variant of the LZ77 algorithm (the sliding windows
algorithm), here we named it LZG in honour of Lance Groody, the
original coder.
After uncompressed it may be handled as RAW_LR.
LZG_UD Uses LZG compression but is drawn from top to bottom as RLE_UD
4.2.2.1 Run length encoding (RLE)
The first byte is allways a control byte, the format is SC. If the control byte is negative, then the next byte must be repeated n times as the bit inverted control byte says, after the next byte (the one that was repeated) another control byte is stored. If the control byte is positive or zero just copy textual the next n bytes where n is the control byte plus one. After that, the next byte is the following control byte. If you reach a control byte but the image size is passed, then you have completed the image.
4.2.2.2 LZ variant (LZG) =
This is a simplified algorithm explanation:
Definition: "print" means to commit a byte into the current location
of the output stream.
The output stream is a slide window initialised with zeros.
The first byte of the input stream is a maskbyte.
For each of the 8 bits in the maskbyte the next actions must be performed:
If the bit is 1 print the next unread byte to the slide window
If the bit is a zero read the next two bytes as control bytes with the
following format (RRRRRRSS SSSSSSSS):
- 6 bits for the copy size number (R). Add 3 to this number.
Range: 2 to 66
- 10 bits for the slide position (S). Add 66 to this number.
Range: 66 to 1090
Then print in the slide window the next R bytes that are the same slide
window starting with the S'th byte.
After all the maskbyte is read and processed, the following input byte is another maskbyte. Use the same procedure to finish uncompressing the file.
This version of the algorithm is limited to 1024 bytes due to the slide window size. In case you want to know the full algorithm and see how it works for bigger images you should use the source, Luke.
This is the full uncompression function source. Note that this is part of PR that is under the GPL license. The variables ??�?R??�? and ??�?S??�? are ??�?rep??�? and ??�?loc??�? respectively. The array output is the output stream and oCursor is the current location. The input array and iCursor variable had the same meaning for the input stream. The algorithm ends when the full input has been processed. The maskbyte must remain with 0 for the unexistent bytes, so if you find the maskbyte not null, it is possible that the input array wasn't a LZG compressed stream. In that case that non-zero value is going to be returned. This is the only internal way to detect an error in the compression layer. All the data that has the latest maskbyte without this issue will be detected as valid and unpacked normally.
Algorithm 4.1: LZG
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/* A big number (the output must be less that that) */
#define LZG_MAX_MEMSIZE 32001
/* modulus to be used in the 10 bits of the algorithm */
#define LZG_WINDOW_SIZE 0x400 /* =1024=1<<10 */
/* LZG expansion algorithm sub function */
unsigned char popBit(unsigned char *byte) {
register unsigned char bit=(*byte)&1;
(*byte)>>=1;
return bit;
}
/* Expands LZ Groody algorithm. This is the core of PR.
* returns 0 on success, non-zero on possible data corruption
*/
int expandLzg(const unsigned char* input, int inputSize,
unsigned char* output, int *outputSize) {
int loc, oCursor=0, iCursor=0;
unsigned char maskbyte=0, rep, k;
/* clean output garbage */
for(loc=LZG_MAX_MEMSIZE;loc--;output[loc]=0);
/* main loop */
while (iCursor<inputSize) {
maskbyte=input[iCursor++];
for (k=8;k&&(iCursor<inputSize);k--) {
if (popBit(&maskbyte)) {
output[oCursor++]=input[iCursor++]; /* copy input to output */
} else {
/*
* loc:
* 10 bits for the slide iCursorition (S). Add 66 to this number.
* rep:
* 6 bits for the repetition number (R). Add 3 to this number.
*/
loc= 66 + ((input[iCursor] & 0x03 /*00000011*/) <<8) + input[iCursor+1];
rep= 3 + ((input[iCursor] & 0xfc /*11111100*/) >>2);
iCursor+=2;
while (rep--) { /* repeat pattern in output */
loc=loc%LZG_WINDOW_SIZE; /* loc is in range 0-1023 */
/*
* delta is ((loc-oCursor)%LZG_WINDOW_SIZE)
* this is the offset where the bytes will be looked for
* in the simple algorithm it is allways negative
* in bigger images it can be iCursoritive
*
* this value is inside the range -1023 to 1023.
* if loc>oCursor the result is iCursoritive
* if loc<oCursor the result is negative
*/
output[oCursor]=output[oCursor+((loc-oCursor)%LZG_WINDOW_SIZE)];
oCursor++;
loc++;
}
}
}
}
*outputSize=oCursor;
return maskbyte;
}
4.3. Palettes
Palettes have 100 bytes allways, after 4 bytes from the beginning the first 16 records of 3 bytes are the VGA colours stored in the RGB-18 bits format (6 bits for each colour). Each colour is a number from 0 to 63. Remember to shift the colour bytes by two to get the colour number from 0 to 256.
4.4. Levels
This table has a summary of the blocks to be used in this section, you can referr it from the text below.
Table 4.1: Level blocks
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Length Offset Block Name 12:30, 11 Aug 2005 (UTC)~ 12:30, 11 Aug 2005 (UTC)~ 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC) 720 0 wall 720 720 background 256 1440 door I 256 1696 door II 96 1952 links 64 2048 unknown I 3 2112 start_position 3 2115 unknown II 1 2116 unknown III 24 2119 guard_location 24 2143 guard_direction 24 2167 unknown VI (a) 24 2191 unknown VI (b) 24 2215 guard_skill 24 2239 unknown VI (c) 24 2263 guard_colour 16 2287 unknown VI (d) 2 2303 0F 09 (2319)
All levels has a size of 2305, except in the original game, that the potion level has a size of 2304 (may be it was wrong trimmed).
4.4.1 Unknown blocks
Blocks described in this section are: Unknown from I to IV.
Unknown III and VI blocks doesn't affect the level if changed, if you find out what they are used to we will welcome your specification text.
Unknown I may corrupt the level if edited.
We believe unknown II has something to do with the start position, but we don't know about it.
As unknown II were all zeros for each level in the original set, it was a team decision to use those bytes for format extension. If one of them is not the default 00 00 00 hex then the level was extended by the team. Those extensions are only supported by RoomShaker at this moment. To see how those extensions were defined read the appendix I'll write some day. For the moment you may contact us if you need to know that.
4.4.2 Room mapping
This section explains how the main walls and objects are stored. The blocks involved here are "wall" and "background"
In a level you can store a maximum of 24 screens (also called rooms) of 30 tiles each, having three stages of 10 tiles each. Screens are numbered from 1 to 24 (not 0 to 23) because the 0 was reserved special cases.
The wall and background blocks have 24 sub-blocks inside. Those sub-blocks has a size of 30 bytes each and has a screen associated. So, for example, the sub-block staring in 0 corresponds to the screen 1 and the sub-block starting in 690 corresponds to the screen 24. It is reserved 1 byte from the wall block and one from the background block for each tile. To locate the appropriate tile you have to do the following calculation: tile=(screen-1)*30+tileOffset where tileOffset is a number from 0 to 29 that means a tile from 0 to 9 if in the upper stage, from 10 to 19 if in the middle stage and 20 to 29 if in the bottom stage. We define this as the location format and will be used also in the start position. Allways looking from the left to the right. So there is a wall and background byte for each tile in the level and this is stored this way.
The wall part of the tile stores the main tile form according to the table below. Note that those are just a limited number of tiles, each code has a tile in the game. The tiles listed are all the ones needed to make a level so the missing tiles have an equivalent in this list.
Each tile has a code id, as some codes are repeated this is how you have to calculate the codes. A tile in the wall part has 8 bits in this format rrmccccc, where rr are random bits and can be ignored. m is a modifier of the tile. For example modified loose floors do not fall down. The rest ccccc is the code of the tile tabled below. Tile names are the same as the ones used by RoomShaker to keep compatibility.
Table 4.2: Foreground Walls
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Hex Binary Group Description Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)~ 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC)~ 0x00 00000 free Empty 0x01 00001 free Floor 0x02 00010 spike Spikes 0x03 00011 none Pillar 0x04 00100 gate Gate 0x05 00101 none Stuck Button 0x06 00110 event Drop Button 0x07 00111 tapest Tapestry 0x08 01000 none Top Big-pillar 0x09 01001 none Bottom Big-pillar 0x0A 01010 potion Potion 0x0B 01011 none Loose Floor 0x0C 01100 ttop Tapestry Top 0x0D 01101 none Mirror 0x0E 01110 none Debris 0x0F 01111 event Raise Button 0x10 10000 none Exit Left 0x11 10001 none Exit Right 0x12 10010 chomp Chopper 0x13 10011 none Torch 0x14 10100 wall Wall 0x15 10101 none Skeleton 0x16 10110 none Sword 0x17 10111 none Balcony Left 0x18 11000 none Balcony Right 0x19 11001 none Lattice Pillar 0x1A 11010 none Lattice Support 0x1B 11011 none Small Lattice 0x1C 11100 none Lattice Left 0x1D 11101 none Lattice Right 0x1E 11110 none Torch with Debris 0x1F 11111 none Null
The background part of the tile stores a modifier or attribute of the wall part of the tile. This works independently of the modifier bit in the code. The tile modifier depends on the group the tile belongs which are wall, chomp, event, ttop, potion, tapp, gate, spike and free. The group event allows the 256 modifiers and will be described in 4.4.6. Note + means allowed for the dungeon environment, - means allowed for the palace environment.
Table 4.3: Background modifiers by group
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Group Code Description 12:30, 11 Aug 2005 (UTC) Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC)~ none 0x00 This value is used allways for this group free 0x00 +Nothing -Blue line free 0x01 +Spot1 -No blue line free 0x02 +Spot2 -Diamond free 0x03 Window free 0xFF +Spot3 -Blue line? spike 0x00 Normal (allows animation) spike 0x01 Barely Out spike 0x02 Half Out spike 0x03 Fully Out spike 0x04 Fully Out spike 0x05 Out? spike 0x06 Out? spike 0x07 Half Out? spike 0x08 Barely Out? spike 0x09 Disabled gate 0x00 Closed gate 0x01 Open tapest 0x00 -With Lattice tapest 0x01 -Alternative Design tapest 0x02 -Normal tapest 0x03 -Black potion 0x00 Empty potion 0x01 Health point potion 0x02 Life potion 0x03 Feather Fall potion 0x04 Invert potion 0x05 Poison potion 0x06 Open ttop 0x00 -With lattice ttop 0x01 -Alernative design ttop 0x02 -Normal ttop 0x03 -Black ttop 0x04 -Black ttop 0x05 -With alternative design and bottom ttop 0x06 -With bottom ttop 0x07 -With window chomp 0x00 Normal chomp 0x01 Half Open chomp 0x02 Closed chomp 0x03 Partially Open chomp 0x04 Extra Open chomp 0x05 Stuck Open wall 0x00 +Normal -Blue line wall 0x01 +Normal -No Blue line
Note: Some modifiers have not been tested, there may be any other unknown
tile type we didn't discover.
4.4.2.1 Wall drawing algorithm
This section doesn't have a direct relation with the format because it describes how the walls must be drawn on the screen. However, as this information should be usefull to recreate a cloned screen read from the format we decided to include this section to the document.
Wall drawing depends on what is in the right panel. If the right panel is not a wall (binary code ends in 10100) a base wall will be drawn and other random seed will be used. If the right panel is a wall then the main base wall will be drawn and the described seed will be used.
When the base wall is drawn, the modifiers should be blitted over it. There are 53 different types of walls using the same base image. We will call the seed array to the one having the modifier information of those 53 panels. This array has indexes from 1 to 53 included.
To calculate what value take from the array this calculation must be performed: panelInfo=seedArray[screenNumber+wallPosition] where panelInfo is the result modifier information that will be applied to the base image; seedArray is this array that will be described above as a table; screenNumber is the number of the screen the wall is (from 1 to 24) and wallPosition is the position the wall is (from 0 to 29), using the location format specified in section 4.4.2. This means the first value is 1 (screenNumber=1 and wallPosition=0) and the last is 53 (screenNumber=24 and wallPosition=29).
Modifiers affects the corners of a stone. There are three stone rows per wall. If the modifier is activated this corner will appear different (seems to be darker). Another modifier is the gray stone.
Table 4.4: Stone modifiers on seed position
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Modifier Seed Positions
12:30, 11 Aug 2005 (UTC)Ecalot Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)Ecalot 12:30, 11 Aug 2005 (UTC)
(First row modifiers)
Gray stone 2, 5, 14, 17, 26, 32, 35, 50
Left, bottom 2, 11, 36, 45
Left, top 37
Right, bottom 27, 33
Right, up 4, 10, 31, 37
(second row) Gray stone none Left, bottom 34, 47 Left, top 9, 10 Right, bottom 2, 8, 25, 35 Right, top 6, 12, 23, 29, 39
(third row) Gray stone none Left, bottom none Left, top 16 Right, bottom none Right, top none
Another modifiers are saved in the seed too. Those modifiers are not boolean values, they are offsets and sizes. As each stone has a different size the stone separation offset is saved in the seed. For the first row, the stones are all the same size and the seed is not needed. For the second row we've got the first 20 values, ordered from 1 to 20. position 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20 offsets: 5,4,3,3,1,5,4,2,1, 1, 5, 3, 2, 1, 5, 4, 3, 2, 5, 4 separator size: 0,1,1,0,0,0,1,1,0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0
We'll be adding the next values as soon as we count the pixels ;) This information can be found in walls.conf file from FreePrince.
4.4.3 Room linking
This section describes the links block.
Each screen is linked to another by each of the four sides. Each link is stored. There is no screen mapping, just screen linking.
The links block has 24 sub-blocks of 4 bytes each. All those sub-blocks has its own correspondence with a screen (the block starting at 0 is related to the screen 1 and the block starting at with 92 is related to screen 24). Each block of 4 bytes stores the links this screen links to reserving one byte per each side in the order left (0), right (1), up (2), down (3). The number 0 is used when there is no screen there. Cross links should be made to allow the kid passing from a screen to another and then coming back to the same screen but it's not a must.
4.4.4 Guard handling
This section specifies the blocks: guard_location, guard_direction, guard_skill and guard_colour.
Each guard section has 24 bytes, each byte of them corresponds to a screen so byte 0 is related to screen 1 and byte 13 is related to screen 24. This screen is where the guard is located. The format only allows one guard per screen. Each block describes a part of the guard.
The guard_location part of a guard describes where in the screen the guard is located, this is a number from 0 to 29 if the guard is in the screen or 30 if there is no guard in this screen. Other values are allowed but are equivalent to 30. The number from 0 to 29 is in the location format specified in section 4.4.2
The guard_direction part describes where the guard looks at. If the value is 0, then the guard looks to the right, if the value is the hex FF (-1 or 255) then he looks left. This is the direction format, and will be used in the start position too.
The guard_skill is how the guard fights, style and lives. Note that the lives also depends on the level you are. Allowed numbers are from 0 to 9.
TODO: add a skill table
The guard_colour is the palette the guard has (see 4.8). The default colours are in this table:
Table 4.4: Default Guard colours
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Code Pants Cape Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC) Ecalot 12:30, 11 Aug 2005 (UTC) 0x00 Light Blue Pink 0x01 Red Purple 0x02 Orange Yellow 0x03 Green Yellow 0x04 Dark Blue Beige 0x05 Purple Beige 0x06 Yellow Orange
Other codes may generate random colours because the game is reading the palette from trashed memory. This may also cause a game crash. It should (never tested) be possible to add new colours in the guard palette resource (see 4.8) avoiding the crash due to this reason.
4.4.5 Starting Position
This section describes the start_position block.
This block stores where and how the kid starts in the level. Note that all level doors that are on the starting screen will be closed in the moment the level starts.
This block has 3 bytes. The first byte is the screen, allowed values are from 1 to 24. The second byte is the location, see the section 4.4.2 for the location format specifications. The third byte is the direction, see 4.4.4 for the direction format specifications.
4.4.6 Door events
This section explains how the doors are handled and specifies the blocks door I and II.
First of all he have to define what an event line is in this file. An event line is a link to a door that will be activated. If the event was triggered with the action close, then the event will close the door, if the action was open then the event will open the door. An event line has also a flag to trigger the next event line or not. An event is defined as a list of event lines, from the first to the last. The last must have the trigger-next-event-line flag off. This is like a list of doors that performs an action. An event performs the action that it was called to do: open those doors or close them. This action is defined by the type of tile pressed. Each event line has an ID from 0 to 255. An event has the ID of the first event line in it.
In section 4.4.2 it is explained how a door trigger is associated to an event ID. Those are the tiles that starts the event depending on what are them: closers or openers.
How events are stored: Each door block has 256 bytes, one per event line. Each event line is located in an offset that is the event line ID, so event line 30 is located in the byte 30 of each block. There is a door I part of an event line and a door II part of it. We'll define them as byte I and byte II. You can find there: the door screen, the door location, and the trigger-next flag. The format is the following:
Let's define: Screen as S and it is a number from 1 to 24 (5 bits) S = s1 s2 s3 s4 s5 where sn is the bit n of the binary representation of S Location as L and is a number from 0 to 29 (5 bits) L = l1 l2 l3 l4 l5 where ln is the bit n of the binary representation of L This number is according to the location format specifications. Trigger-next as T and is a 1 for "on" or a 0 for "off" (1 bit) T = t1
Byte I has the form: t1 s4 s5 l1 l2 l3 l4 l5 Byte II has the form: s1 s2 s3 0 0 0 0 0
4.5. Digital Waves
Read them as raw digital wave sound using the following specifications:
Table 4.4: Wave Specifications
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Size of Format: 16
Format: PCM
Attributes: 8 bit, mono, unsigned
Channels: 1
Sample rate: 11025
Bytes/Second: 11025
Block Align: 1
GNU/Linux users can play the raw waves just dropping them inside /dev/dsp As dat headers are very small it is valid to type in a shell console with dsp write access: cat digisnd?.dat>/dev/dsp to play the whole wave files.
4.6. Midi music
Standard midi files
4.7. Internal PC Speaker
We are not so sure about it, but we think it is: 2 unique bytes for headers 3 bytes per note (2 for frequency and 1 for duration)
4.8. Binary files
Some binary files contains relevant information The resource number 10 in prince.dat has the VGA guard palettes in it saving n records of a 16-colour-palette of 3 bytes in the specified palette format.
5. DAT v2.0 Format Specifications
5.1. General file specs, index and checksums
POP2 DAT files aren't much different from their predecessors from POP1. The format is similar in almost each way. The main difference is in the index. As DAT v1.0 used an index in the high data, the DAT v2.0 indexes are two level encapsulated inside a high data. So there is an index of indexes.
We will use the same conventions than in the prior chapter. The checksum validations are still the same.
High data structures:
The DAT header: Size = 6 bytes
- Offset 0, size 4, type UL: HighDataOffset
(the location where the highData begins)
- Offset 4, size 2, type US: HighDataSize
(the number of bytes the highData has)
Note that HighDataOffset+HighDataSize=file size
This is similar to DAT v1.0 format, except that the index area is now called high data.
The high data part of the file contains multiple encapsulated indexes. Each of those index is indexed in a high data index of indexes. We will call this index the ??�?master index??�? and the sub index the ??�?slave indexes??�?. Slave indexes are the real file contents index.
5.2. The master index
The master index is made with:
- Offset HighDataOffset, size 2, type US: NumberOfSlaveIndexes
(the number of the high data sections)
- Offset HighDataOffset+2, size NumberOfSlaveIndexes*6: The master index record
(a list of NumberOfSlaveIndexes blocks of 6-bytes-length index
record each corresponding to one slave index)
The 6-bytes-length index record (one per item): Size = 6 bytes
- Relative offset 0, size 4, type sting: 4 ASCII bytes string denoting
the section ID. The character order is inverted.
- Relative offset 4, size 2, type US: SlaveIndexOffset
(slave index offset relative to HighDataOffset)
From the end of the DAT High Data index to the end of the file there is the High Data section contents (where the HighDataOffset relative offsets points to).
There are different 4 bytes ASCII strings section IDs. When the string is less than 4 bytes, they are ended in hex 0x00 is used. We will denote it with the cardinal # symbol. The character order is inverted, so for example the text SLAP becomes PALS, MARF becomes FRAM, #### becomes empty or RCS# becomes SCR. They must be un upper case.
Table 5.1: Section ID strings
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ID Size in records ~~ 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC) cust custom font fonts fram frames palc CGA Palette pals SVGA Palette palt TGA Palette piec Pieces psl ? scr Screens (images that have the full screen) shap Shapes (normal graphics) shpl Shape palettes strl Str snd Sound seqs Midi sequences txt4 Text
5.3. The slave indexes
All encapsulated sections are indexes.
The slave index is made with:
- Offset SlaveIndexOffset, size 2, type US: NumberOfItems
(the number of the records referring to the file data)
- Offset SlaveIndexOffset+2, size NumberOfItems*11: The slave index record
(a list of NumberOfItems blocks of 11-bytes-length index record
each corresponding to one slave index)
The 11-bytes-length slave index record (one per item): Size = 11 bytes
- Relative offset 0, size 2, type US: Item ID
- Relative offset 2, size 4, type UL: Resource start
(absolute offset in file)
- Relative offset 6, size 2, type US: Size of the item
(not including the checksum byte)
- Relative offset 8, size 3, type binary: A flags mask
(in PAHS indexes it's allways 0x40 0x00 0x00;
in others 0x00 0x00 0x00)
6. PLV v1.0 Format Specifications
PLV v1.0 files are defined in this table:
Table 6.1: PLV blocks
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Size Offset Description Type Content Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)~ 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC)~ Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)~~ 7 0 Magic identifier text "POP_LVL" 1 7 POP version UC 0x01 1 8 PLV version UC 0x01 1 9 Level Number UC 4 10 Number of fields UL 4 14 Block 1: Level size (B1) UL 2306/2305 B1 18 Block 1: Level code - 4 18+B1 Block 2: User data size (B2) UL B2 22+B1 Block 2: User data -
Level code is the exact level as described in 4.4 including the checksum byte. Note that Level size also includes the checksum byte in the count. POP version is 1 for POP1 and 2 for POP2. PLV version is 1 for PLV v1.0. Only one level may be saved in a PLV, the level number is saved inside.
6.1. User data
User data is a block of extensible information, Number of fields is the count of each field/value information pair. A pair is saved in the following format: field_name\0value\0 where \0 is the null byte (0x00) and field_name and value are strings.
There are mandatory pairs that must be included in all PLV files. Those are:
Table 6.2: Mandatory Fields
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Field name Description
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Editor Name The name of the editor used to save the file
Editor Version The version of the editor used to save the file
Level Author The author of the file
Level Title A title for the level
Level Description A description
Time Created The time when the file was created
Time Last Modified The time of the last modification to the file
Original Filename The name of the original file name (levels.dat)
Original Level Number Optional. The level number it has when it was
first exported
The content values may be empty. There is no need to keep an order within
the fields.
6.2. Allowed Date format
To make easy time parsing the time format must be very strict. There are only two allowed formats: with seconds and without. With seconds the format is "YYYY-MM-DD HH:II:SS" Without seconds the format is "YYYY-MM-DD HH:II" Where YYYY is the year in 4 digits, MM is the month in numbers, MM the months, DD the days, HH the hour, II the minute and SS the second in the military time: HH is a number from 00 to 23.
If the month, day, hour or second have only one digit, the other digit must be completed with 0. i.e. 2002-11-26 22:16:39
7. The SAV v1.0 format
SAV v1.0 saves kid level, lives and remaining time information in order to restart the game from this position.
SAV files are 8 bytes length in the following format:
Table 7.1: SAV blocks
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Size Offset Description Type Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)~ 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC)~ Ecalot 12:30, 11 Aug 2005 (UTC) 2 0 Remaining minutes US (i) 2 2 Remaining ticks US (ii) 2 4 Current level US (iii) 2 6 Current hit points US (iv)
Remaining minutes (i) Range values: 0 to 32766 for minutes 32767 to 65534 for NO TIME (but the time is stored) 65535 for game over
Remaining ticks (ii) Seconds are stored in ticks, a tick is 1/12 seconds. To get the time in seconds you have to divide the integer "Remaining ticks" by 12.
Range values:
0.000 to 59.916 seconds
(rounded by units of 83 milliseconds or 1/12 seconds)
0 to 719 ticks
Level (iii) Range values: 1 to 12 for normal levels 13 for 12bis 14 for princess level 15 for potion level
Hit points (iv) Range values: 0 for an immediate death 1 to 65535 lives
8. The HOF v1.0 format
HOF files are used to save the Hall of Fame information.
All HOF v1.0 files have a size of 176 bytes. The first 2 bytes belongs to the record count. The format is US. The maximum number of records allowed is 6, so the second byte is allways 0x00. Following those bytes there is an array of records. This array has a full size of 29 bytes distributed according to the following table.
Table 8.1: HOF blocks
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Size Offset Description Type Ecalot 12:30, 11 Aug 2005 (UTC) 12:30, 11 Aug 2005 (UTC)~ 12:30, 11 Aug 2005 (UTC)12:30, 11 Aug 2005 (UTC)~ Ecalot 12:30, 11 Aug 2005 (UTC) 25 0 Player name text 2 25 Remaining minutes US (similar to SAV format) 2 27 Remaining ticks US (similar to SAV format)
In case there is no record, the 29 bytes spaces must be filled with zeros in order to complete the whole file and give it the size of 2+29*6 = 176.
9. Credits
This document: Writing . . . . . . . . . . . . . . . . . . . . . . . . . Enrique Calot Corrections . . . . . . . . . . . . . . . . . . . . . Patrik Jakobsson
Reverse Engineering:
Indexes . . . . . . . . . . . . . . . . . . . . . . . . . Enrique Calot
Levels . . . . . . . . . . . . . . . . . . . . . . . . . Enrique Calot
Brendon James
Images . . . . . . . . . . . . . . . . . . . . . . . Tammo Jan Dijkema
RLE Compression . . . . . . . . . . . . . . . . . . . Tammo Jan Dijkema
LZG Compression . . . . . . . . . . . . . . . . . . . . . Anke Balderer
Sounds . . . . . . . . . . . . . . . . . . . . . . . Christian Lundheim
PLV v1.0:
Definition . . . . . . . . . . . . . . . . . . . . . . . Brendon James
Enrique Calot
10. License
Copyright (c) 2004, 2005 The Princed Project Team
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
Texts. A copy of the license is included in the section entitled
"GNU Free Documentation License".
