// Emacs style mode select   -*- C++ -*-
//-----------------------------------------------------------------------------
//
// $Id:$
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This source is available for distribution and/or modification
// only under the terms of the DOOM Source Code License as
// published by id Software. All rights reserved.
//
// The source is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
// for more details.
//
// $Log:$
//
// Revision 1.3  1997/01/29 20:10
// DESCRIPTION:
//      Preparation of data for rendering,
//      generation of lookups, caching, retrieval by name.
//
//-----------------------------------------------------------------------------


static const char
rcsid[] = "$Id: r_data.c,v 1.4 1997/02/03 16:47:55 b1 Exp $";

#include "i_system.h"
#include "z_zone.h"

#include "m_swap.h"

#include "w_wad.h"

#include "doomdef.h"
#include "r_local.h"
#include "p_local.h"

#include "doomstat.h"
#include "r_sky.h"

#ifdef LINUX
#include  <alloca.h>
#endif

#if defined(OS2) || defined (DOS)
#include <malloc.h>
#endif

#include "r_data.h"

//
// Graphics.
// DOOM graphics for walls and sprites
// is stored in vertical runs of opaque pixels (posts).
// A column is composed of zero or more posts,
// a patch or sprite is composed of zero or more columns.
//



//
// Texture definition.
// Each texture is composed of one or more patches,
// with patches being lumps stored in the WAD.
// The lumps are referenced by number, and patched
// into the rectangular texture space using origin
// and possibly other attributes.
//
typedef struct
{
    short       originx;
    short       originy;
    short       patch;
    short       stepdir;
    short       colormap;
} mappatch_t;


//
// Texture definition.
// A DOOM wall texture is a list of patches
// which are to be combined in a predefined order.
//
typedef struct
{
    char                name[8];
    int                 dummy; /* masked; */
    short               width;
    short               height;
    void                **columndirectory;      // OBSOLETE
    short               patchcount;
    mappatch_t  patches[1];
} maptexture_t;


// A single patch from a texture definition,
//  basically a rectangular area within
//  the texture rectangle.
typedef struct
{
    // Block origin (allways UL),
    // which has allready accounted
    // for the internal origin of the patch.
    int         originx;
    int         originy;
    int         patch;
} texpatch_t;


// A maptexturedef_t describes a rectangular texture,
//  which is composed of one or more mappatch_t structures
//  that arrange graphic patches.
typedef struct
{
    // Keep name for switch changing, etc.
    char        name[8];
    short       width;
    short       height;

    // All the patches[patchcount]
    //  are drawn back to front into the cached texture.
    short       patchcount;
    texpatch_t  patches[1];

} texture_t;



int             firstflat;
int             lastflat;
int             numflats;

int             firstpatch;
int             lastpatch;
int             numpatches;

int             firstspritelump;
int             lastspritelump;
int             numspritelumps;

int             numtextures;
texture_t**     textures;


int*                    texturewidthmask;
// needed for texture pegging
fixed_t*                textureheight;
int*                    texturecompositesize;
short**                 texturecolumnlump;
unsigned short**        texturecolumnofs;
byte**                  texturecomposite;

// for global animation
int*            flattranslation;
int*            texturetranslation;

// needed for pre rendering
fixed_t*        spritewidth;
fixed_t*        spriteoffset;
fixed_t*        spritetopoffset;

lighttable_t    *colormaps;


//
// MAPTEXTURE_T CACHING
// When a texture is first needed,
//  it counts the number of composite columns
//  required in the texture and allocates space
//  for a column directory and any new columns.
// The directory will simply point inside other patches
//  if there is only one patch in a given column,
//  but any columns with multiple patches
//  will have new column_ts generated.
//



//
// R_DrawColumnInCache
// Clip and draw a column
//  from a patch into a cached post.
//
void
R_DrawColumnInCache
( column_t*     patch,
  byte*         cache,
  int           originy,
  int           cacheheight )
{
    int         count;
    int         position;
    byte*       source;
    byte*       dest;

    dest = (byte *)cache + 3;

    while (patch->topdelta != 0xff)
    {
        source = (byte *)patch + 3;
        count = patch->length;
        position = originy + patch->topdelta;

        if (position < 0)
        {
            count += position;
            position = 0;
        }

        if (position + count > cacheheight)
            count = cacheheight - position;

        if (count > 0)
            memcpy (cache + position, source, count);

        patch = (column_t *)(  (byte *)patch + patch->length + 4);
    }
}



//
// R_GenerateComposite
// Using the texture definition,
//  the composite texture is created from the patches,
//  and each column is cached.
//
void R_GenerateComposite (int texnum)
{
    byte*               block;
    texture_t*          texture;
    texpatch_t*         patch;
    patch_t*            realpatch;
    int                 x;
    int                 x1;
    int                 x2;
    int                 i;
    column_t*           patchcol;
    short*              collump;
    unsigned short*     colofs;

    texture = textures[texnum];

    block = Z_Malloc (texturecompositesize[texnum],
                      PU_STATIC,
                      &texturecomposite[texnum]);

    collump = texturecolumnlump[texnum];
    colofs = texturecolumnofs[texnum];

    // Composite the columns together.
    patch = texture->patches;

    for (i=0 , patch = texture->patches;
         i<texture->patchcount;
         i++, patch++)
    {
        realpatch = W_CacheLumpNum (patch->patch, PU_CACHE);
        x1 = patch->originx;
        x2 = x1 + SHORT(realpatch->width);

        if (x1<0)
            x = 0;
        else
            x = x1;

        if (x2 > texture->width)
            x2 = texture->width;

        for ( ; x<x2 ; x++)
        {
            // Column does not have multiple patches?
            if (collump[x] >= 0)
                continue;

            patchcol = (column_t *)((byte *)realpatch
                                    + LONG(realpatch->columnofs[x-x1]));
            R_DrawColumnInCache (patchcol,
                                 block + colofs[x],
                                 patch->originy,
                                 texture->height);
        }

    }

    // Now that the texture has been built in column cache,
    //  it is purgable from zone memory.
    Z_ChangeTag (block, PU_CACHE);
}



//
// R_GenerateLookup
//
void R_GenerateLookup (int texnum)
{
    texture_t*          texture;
    byte*               patchcount;     // patchcount[texture->width]
    texpatch_t*         patch;
    patch_t*            realpatch;
    int                 x;
    int                 x1;
    int                 x2;
    int                 i;
    short*              collump;
    unsigned short*     colofs;

    texture = textures[texnum];

    // Composited texture not created yet.
    texturecomposite[texnum] = 0;

    texturecompositesize[texnum] = 0;
    collump = texturecolumnlump[texnum];
    colofs = texturecolumnofs[texnum];

    // Now count the number of columns
    //  that are covered by more than one patch.
    // Fill in the lump / offset, so columns
    //  with only a single patch are all done.
    patchcount = (byte *)alloca (texture->width);
    memset (patchcount, 0, texture->width);
    patch = texture->patches;

    for (i=0 , patch = texture->patches;
         i<texture->patchcount;
         i++, patch++)
    {
        realpatch = W_CacheLumpNum (patch->patch, PU_CACHE);
        x1 = patch->originx;
        x2 = x1 + SHORT(realpatch->width);

        if (x1 < 0)
            x = 0;
        else
            x = x1;

        if (x2 > texture->width)
            x2 = texture->width;
        for ( ; x<x2 ; x++)
        {
            patchcount[x]++;
            collump[x] = patch->patch;
            colofs[x] = LONG(realpatch->columnofs[x-x1])+3;
        }
    }

    for (x=0 ; x<texture->width ; x++)
    {
        if (!patchcount[x])
        {
            printf ("R_GenerateLookup: column without a patch (%s)\n",
                    texture->name);
            return;
        }
        // I_Error ("R_GenerateLookup: column without a patch");

        if (patchcount[x] > 1)
        {
            // Use the cached block.
            collump[x] = -1;
            colofs[x] = texturecompositesize[texnum];

            if (texturecompositesize[texnum] > 0x10000-texture->height)
            {
                I_Error ("R_GenerateLookup: texture %i is >64k",
                         texnum);
            }

            texturecompositesize[texnum] += texture->height;
        }
    }
}




//
// R_GetColumn
//
byte*
R_GetColumn
( int           tex,
  int           col )
{
    int         lump;
    int         ofs;

    col &= texturewidthmask[tex];
    lump = texturecolumnlump[tex][col];
    ofs = texturecolumnofs[tex][col];

    if (lump > 0)
        return (byte *)W_CacheLumpNum(lump,PU_CACHE)+ofs;

    if (!texturecomposite[tex])
        R_GenerateComposite (tex);

    return texturecomposite[tex] + ofs;
}




//
// R_InitTextures
// Initializes the texture list
//  with the textures from the world map.
//
void R_InitTextures (void)
{
    maptexture_t*       mtexture;
    texture_t*          texture;
    mappatch_t*         mpatch;
    texpatch_t*         patch;

    int                 i;
    int                 j;

    int*                maptex;
    int*                maptex2;
    int*                maptex1;

    char                name[9];
    char*               names;
    char*               name_p;

    int*                patchlookup;

    int                 totalwidth;
    int                 nummappatches;
    int                 offset;
    int                 maxoff;
    int                 maxoff2;
    int                 numtextures1;
    int                 numtextures2;

    int*                directory;

    int                 temp1;
    int                 temp2;
    int                 temp3;


    // Load the patch names from pnames.lmp.
    name[8] = 0;
    names = W_CacheLumpName ("PNAMES", PU_STATIC);
    nummappatches = LONG ( *((int *)names) );
    name_p = names+4;
    patchlookup = alloca (nummappatches*sizeof(*patchlookup));

    for (i=0 ; i<nummappatches ; i++)
    {
        strncpy (name,name_p+i*8, 8);
        patchlookup[i] = W_CheckNumForName (name);
    }
    Z_Free (names);

    // Load the map texture definitions from textures.lmp.
    // The data is contained in one or two lumps,
    //  TEXTURE1 for shareware, plus TEXTURE2 for commercial.
    maptex = maptex1 = W_CacheLumpName ("TEXTURE1", PU_STATIC);
    numtextures1 = LONG(*maptex);
    maxoff = W_LumpLength (W_GetNumForName ("TEXTURE1"));
    directory = maptex+1;

    if (W_CheckNumForName ("TEXTURE2") != -1)
    {
        maptex2 = W_CacheLumpName ("TEXTURE2", PU_STATIC);
        numtextures2 = LONG(*maptex2);
        maxoff2 = W_LumpLength (W_GetNumForName ("TEXTURE2"));
    }
    else
    {
        maptex2 = NULL;
        numtextures2 = 0;
        maxoff2 = 0;
    }
    numtextures = numtextures1 + numtextures2;

    textures = Z_Malloc (numtextures*4, PU_STATIC, 0);
    texturecolumnlump = Z_Malloc (numtextures*4, PU_STATIC, 0);
    texturecolumnofs = Z_Malloc (numtextures*4, PU_STATIC, 0);
    texturecomposite = Z_Malloc (numtextures*4, PU_STATIC, 0);
    texturecompositesize = Z_Malloc (numtextures*4, PU_STATIC, 0);
    texturewidthmask = Z_Malloc (numtextures*4, PU_STATIC, 0);
    textureheight = Z_Malloc (numtextures*4, PU_STATIC, 0);

    totalwidth = 0;

    //  Really complex printing shit...
    temp1 = W_GetNumForName ("S_START");  // P_???????
    temp2 = W_GetNumForName ("S_END") - 1;
    temp3 = ((temp2-temp1+63)/64) + ((numtextures+63)/64);
    printf("[");
    for (i = 0; i < temp3; i++)
        printf(" ");
    printf("         ]");
    for (i = 0; i < temp3; i++)
        printf("\x8");
    printf("\x8\x8\x8\x8\x8\x8\x8\x8\x8\x8");

    for (i=0 ; i<numtextures ; i++, directory++)
    {
        if (!(i&63))
            printf (".");

        if (i == numtextures1)
        {
            // Start looking in second texture file.
            maptex = maptex2;
            maxoff = maxoff2;
            directory = maptex+1;
        }

        offset = LONG(*directory);

        if (offset > maxoff)
            I_Error ("R_InitTextures: bad texture directory");

        mtexture = (maptexture_t *) ( (byte *)maptex + offset);

        texture = textures[i] =
            Z_Malloc (sizeof(texture_t)
                      + sizeof(texpatch_t)*(SHORT(mtexture->patchcount)-1),
                      PU_STATIC, 0);

        texture->width = SHORT(mtexture->width);
        texture->height = SHORT(mtexture->height);
        texture->patchcount = SHORT(mtexture->patchcount);

        memcpy (texture->name, mtexture->name, sizeof(texture->name));
        mpatch = &mtexture->patches[0];
        patch = &texture->patches[0];

        for (j=0 ; j<texture->patchcount ; j++, mpatch++, patch++)
        {
            patch->originx = SHORT(mpatch->originx);
            patch->originy = SHORT(mpatch->originy);
            patch->patch = patchlookup[SHORT(mpatch->patch)];
            if (patch->patch == -1)
            {
                I_Error ("R_InitTextures: Missing patch in texture %s",
                         texture->name);
            }
        }
        texturecolumnlump[i] = Z_Malloc (texture->width*2, PU_STATIC,0);
        texturecolumnofs[i] = Z_Malloc (texture->width*2, PU_STATIC,0);

        j = 1;
        while (j*2 <= texture->width)
            j<<=1;

        texturewidthmask[i] = j-1;
        textureheight[i] = texture->height<<FRACBITS;

        totalwidth += texture->width;
    }

    Z_Free (maptex1);
    if (maptex2)
        Z_Free (maptex2);

    // Precalculate whatever possible.
    for (i=0 ; i<numtextures ; i++)
        R_GenerateLookup (i);

    // Create translation table for global animation.
    texturetranslation = Z_Malloc ((numtextures+1)*4, PU_STATIC, 0);

    for (i=0 ; i<numtextures ; i++)
        texturetranslation[i] = i;
}



//
// R_InitFlats
//
void R_InitFlats (void)
{
    int         i;

    firstflat = W_GetNumForName ("F_START") + 1;
    lastflat = W_GetNumForName ("F_END") - 1;
    numflats = lastflat - firstflat + 1;

    // Create translation table for global animation.
    flattranslation = Z_Malloc ((numflats+1)*4, PU_STATIC, 0);

    for (i=0 ; i<numflats ; i++)
        flattranslation[i] = i;
}


//
// R_InitSpriteLumps
// Finds the width and hoffset of all sprites in the wad,
//  so the sprite does not need to be cached completely
//  just for having the header info ready during rendering.
//
void R_InitSpriteLumps (void)
{
    int         i;
    patch_t     *patch;

    firstspritelump = W_GetNumForName ("S_START") + 1;
    lastspritelump = W_GetNumForName ("S_END") - 1;

    numspritelumps = lastspritelump - firstspritelump + 1;
    spritewidth = Z_Malloc (numspritelumps*4, PU_STATIC, 0);
    spriteoffset = Z_Malloc (numspritelumps*4, PU_STATIC, 0);
    spritetopoffset = Z_Malloc (numspritelumps*4, PU_STATIC, 0);

    for (i=0 ; i< numspritelumps ; i++)
    {
        if (!(i&63))
            printf (".");

        patch = W_CacheLumpNum (firstspritelump+i, PU_CACHE);
        spritewidth[i] = SHORT(patch->width)<<FRACBITS;
        spriteoffset[i] = SHORT(patch->leftoffset)<<FRACBITS;
        spritetopoffset[i] = SHORT(patch->topoffset)<<FRACBITS;
    }
}



//
// R_InitColormaps
//
void R_InitColormaps (void)
{
    int lump, length;

    // Load in the light tables,
    //  256 byte align tables.
    lump = W_GetNumForName("COLORMAP");
    length = W_LumpLength (lump) + 255;
    colormaps = Z_Malloc (length, PU_STATIC, 0);
    colormaps = (byte *)( ((int)colormaps + 255)&~0xff);
    W_ReadLump (lump,colormaps);
}



//
// R_InitData
// Locates all the lumps
//  that will be used by all views
// Must be called after W_Init.
//
void R_InitData (void)
{
    R_InitTextures ();
    printf ("\nInitTextures");
    R_InitFlats ();
    printf ("\nInitFlats");
    R_InitSpriteLumps ();
    printf ("\nInitSprites");
    R_InitColormaps ();
    printf ("\nInitColormaps");
}



//
// R_FlatNumForName
// Retrieval, get a flat number for a flat name.
//
int R_FlatNumForName (char* name)
{
    int         i;
    char        namet[9];

    i = W_CheckNumForName (name);

    if (i == -1)
    {
        namet[8] = 0;
        memcpy (namet, name,8);
        I_Error ("R_FlatNumForName: %s not found",namet);
    }
    return i - firstflat;
}




//
// R_CheckTextureNumForName
// Check whether texture is available.
// Filter out NoTexture indicator.
//
int     R_CheckTextureNumForName (char *name)
{
    int         i;

    // "NoTexture" marker.
    if (name[0] == '-')
        return 0;

    for (i=0 ; i<numtextures ; i++)
        #if defined(OS2) || defined (DOS)
          if (!strnicmp (textures[i]->name, name, 8) )
        #else
          if (!strncasecmp (textures[i]->name, name, 8) )
        #endif
            return i;

    return -1;
}



//
// R_TextureNumForName
// Calls R_CheckTextureNumForName,
//  aborts with error message.
//
int     R_TextureNumForName (char* name)
{
    int         i;

    i = R_CheckTextureNumForName (name);

    if (i==-1)
    {
        I_Error ("R_TextureNumForName: %s not found",
                 name);
    }
    return i;
}




//
// R_PrecacheLevel
// Preloads all relevant graphics for the level.
//
int             flatmemory;
int             texturememory;
int             spritememory;

void R_PrecacheLevel (void)
{
    char*               flatpresent;
    char*               texturepresent;
    char*               spritepresent;

    int                 i;
    int                 j;
    int                 k;
    int                 lump;

    texture_t*          texture;
    thinker_t*          th;
    spriteframe_t*      sf;

    if (demoplayback)
        return;

    // Precache flats.
    flatpresent = alloca(numflats);
    memset (flatpresent,0,numflats);

    for (i=0 ; i<numsectors ; i++)
    {
        flatpresent[sectors[i].floorpic] = 1;
        flatpresent[sectors[i].ceilingpic] = 1;
    }

    flatmemory = 0;

    for (i=0 ; i<numflats ; i++)
    {
        if (flatpresent[i])
        {
            lump = firstflat + i;
            flatmemory += lumpinfo[lump].size;
            W_CacheLumpNum(lump, PU_CACHE);
        }
    }

    // Precache textures.
    texturepresent = alloca(numtextures);
    memset (texturepresent,0, numtextures);

    for (i=0 ; i<numsides ; i++)
    {
        texturepresent[sides[i].toptexture] = 1;
        texturepresent[sides[i].midtexture] = 1;
        texturepresent[sides[i].bottomtexture] = 1;
    }

    // Sky texture is always present.
    // Note that F_SKY1 is the name used to
    //  indicate a sky floor/ceiling as a flat,
    //  while the sky texture is stored like
    //  a wall texture, with an episode dependend
    //  name.
    texturepresent[skytexture] = 1;

    texturememory = 0;
    for (i=0 ; i<numtextures ; i++)
    {
        if (!texturepresent[i])
            continue;

        texture = textures[i];

        for (j=0 ; j<texture->patchcount ; j++)
        {
            lump = texture->patches[j].patch;
            texturememory += lumpinfo[lump].size;
            W_CacheLumpNum(lump , PU_CACHE);
        }
    }

    // Precache sprites.
    spritepresent = alloca(numsprites);
    memset (spritepresent,0, numsprites);

    for (th = thinkercap.next ; th != &thinkercap ; th=th->next)
    {
        if (th->function.acp1 == (actionf_p1)P_MobjThinker)
            spritepresent[((mobj_t *)th)->sprite] = 1;
    }

    spritememory = 0;
    for (i=0 ; i<numsprites ; i++)
    {
        if (!spritepresent[i])
            continue;

        for (j=0 ; j<sprites[i].numframes ; j++)
        {
            sf = &sprites[i].spriteframes[j];
            for (k=0 ; k<8 ; k++)
            {
                lump = firstspritelump + sf->lump[k];
                spritememory += lumpinfo[lump].size;
                W_CacheLumpNum(lump , PU_CACHE);
            }
        }
    }
}




