Revision as of 23:14, 16 April 2019

picture format edits

Hi Wesley, I wanted to approve these edits but I'm not sure they're correct. You state "There is also a different picture format used for the starting screens, help pages, and the Heretic picture format.". Do you mean TITLEPIC by starting screens, or something else? I'm not aware of a different picture format for TITLEPIC/HELP/CREDIT etc., nor changes made for Heretic. Can you elaborate, please? — Shambler (talk) 08:10, 15 April 2019 (CDT)

It is not clear how this discussion is supposed to take place, this does not seem to be a forum.

The first question is going to be what this particular page is going to be about? Is it just about patch format? (then it should call it patch format and not picture format). If it is about all the formats then it might have to admit to png and the other formats that some other ports use.

I cleaned up the Doom picture format page because it seemed to be about the patch format, and kept trying to call it something else. The sentence about other formats is true, there are other formats in the modern implementations of Doom. The vanilla Doom may be pretty close to using patches for everything, but not many people who are going to explore the code are going to go to that source. I left it an ambiguous sentence that warned them to look out for other formats when these other page types are concerned.

I spent several hours tracking down specifics, and then had to give that up because it was open-ended work.

This is what I found out looking at DoomLegacy.

Doom Large Images From doom.wad Graphics

TITLEPIC, HELP1, INTERPIC  patch
WIMAP0, WIMAP1, WIMAP2   patch
M_DOOM    patch
END sequence   patch
ENDPIC, PFUB1 PFUB2, VICTORY2  patch

Patches

SKY1, SKY2, SKY3, SKY4     patch

Sprites

- all monster, weapon, object patches

From doom2.wad Graphics

TITLEPIC, BOSSBACK, CREDIT, HELP, INTERPIC  patch
M_DOOM    patch
- several menu labels  patch
- map names            patch

Patches

RSKY1, RSKY2, RSKY3     patch
- all wall texture patches

Sprites

- all monster, weapon, object patches

Textures

texture lump

From heretic.wad Graphics

M_HTIC     patch
MAPE1, MAPE2, MAPE3   patch

Lumps

CREDIT, TITLE, E2END      raw
FINAL1, FINAL2   raw
HELP1, HELP2     raw

Patches

SKY1, SKY2, SKY3     patch

From legacy.wad

CREDIT    patch
RSKY1, RSKY2, RSKY3     patch
- several menu labels  patch
  RANKINGS  patch

Lumps

SBOHEALT  lmp  pic_t
SBOARMOR  lmp  pic_t
SBOEMPTY  lmp  pic_t
SBOFRAGS  lmp  pic_t

Doom

HELP1, HELP2
-> V_DrawScalePatch

Doom2

HELP, CREDIT
-> V_DrawScalePatch

Heretic

HELP1, HELP2
-> V_DrawRawScreen_Num

Doom status bar overlay - draws status bar images that are lumps stored in pic_t format

 - DoomLegacy feature, lumps are from legacy.wad
   - status bar health   SBOHEALT
   - status bar armor    SBOARMOR
   - status bar frags    SBOFRAGS
-> V_DrawScalePic_Num
   -> W_CachePicNum
   -> V_BlitScalePic

Func D_PageDrawer // Draws whole screen patches. // Fills the borders by repeating a flat. // Used for TITLEPIC, HELP1, HELP2, ORDER, CREDIT, FINAL1, FINAL2, E2END

Func V_DrawScalePic_Num // Used for Legacy overlay graphics

-> W_CachePicNum
-> V_BlitScalePic

Func V_DrawRawScreen // Used for Legacy credits. // Used for heretic: TITLE, HELP1, HELP2, ORDER, CREDIT, FINAL1, FINAL2, E2END

 -> W_CacheRawAsPic
 -> V_BlitScalePic

Func W_CacheRawAsPic // convert raw heretic picture to legacy pic_t format // Used for heretic: TITLE, HELP1, HELP2, ORDER, CREDIT, FINAL1, FINAL2, E2END

Func W_CachePicName, W_CachePicNum - reads a lump that is in pic_t format

Func V_BlitScalePic - renders images that are in pic_t format

 - can only draw pic mode = PALETTE
 - the usual pic are sized for 320x200

// This is the Doom PIC format (not the Pictor PIC format). typedef enum {

   PALETTE         = 0,  // 1 byte is the index in the doom palette (as usual)
   INTENSITY       = 1,  // 1 byte intensity
   INTENSITY_ALPHA = 2,  // 2 byte : alpha then intensity
   RGB24           = 3,  // 24 bit rgb
   RGBA32          = 4,  // 32 bit rgba

} pic_mode_t;

pic_t image format

   uint16_t  width;
   byte      zero;   // set to 0 allow autodetection of pic_t 
                     // mode instead of patch or raw
   byte      mode;   // see pic_mode_t above
   uint16_t  height;
   uint16_t  reserved1;  // set to 0
   byte      data[0];

In spite of the mode definition above, all actual Doom pic seem to be mode 0.

Flats - stored as a raw image without a header - original was 64x64 raw image

 - DoomLegacy will accept other square sizes, upto 256x256

- drawn horizontally (by rows)

func R_GetFlat // just reads a lump into a cache