rockbox/apps/plugins/doom/r_plane.c
Dave Chapman 47f4a458d6 Patch #2969 - Doom! Currently only working on the H300.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@9312 a1c6a512-1295-4272-9138-f99709370657
2006-03-28 15:44:01 +00:00

434 lines
12 KiB
C

/* Emacs style mode select -*- C++ -*-
*-----------------------------------------------------------------------------
*
*
* PrBoom a Doom port merged with LxDoom and LSDLDoom
* based on BOOM, a modified and improved DOOM engine
* Copyright (C) 1999 by
* id Software, Chi Hoang, Lee Killough, Jim Flynn, Rand Phares, Ty Halderman
* Copyright (C) 1999-2000 by
* Jess Haas, Nicolas Kalkhof, Colin Phipps, Florian Schulze
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*
* DESCRIPTION:
* Here is a core component: drawing the floors and ceilings,
* while maintaining a per column clipping list only.
* Moreover, the sky areas have to be determined.
*
* MAXVISPLANES is no longer a limit on the number of visplanes,
* but a limit on the number of hash slots; larger numbers mean
* better performance usually but after a point they are wasted,
* and memory and time overheads creep in.
*
* For more information on visplanes, see:
*
* http://classicgaming.com/doom/editing/
*
* Lee Killough
*
*-----------------------------------------------------------------------------*/
#include "z_zone.h" /* memory allocation wrappers -- killough */
#include "doomstat.h"
#include "w_wad.h"
#include "r_main.h"
#include "r_draw.h"
#include "r_things.h"
#include "r_sky.h"
#include "r_plane.h"
#include "rockmacros.h"
#define MAXVISPLANES 128 /* must be a power of 2 */
static visplane_t *visplanes[MAXVISPLANES] IBSS_ATTR; // killough
static visplane_t *freetail; // killough
static visplane_t **freehead = &freetail; // killough
visplane_t *floorplane, *ceilingplane;
// killough -- hash function for visplanes
// Empirically verified to be fairly uniform:
#define visplane_hash(picnum,lightlevel,height) \
((unsigned)((picnum)*3+(lightlevel)+(height)*7) & (MAXVISPLANES-1))
size_t maxopenings;
short *openings,*lastopening;
// Clip values are the solid pixel bounding the range.
// floorclip starts out SCREENHEIGHT
// ceilingclip starts out -1
short floorclip[SCREENWIDTH], ceilingclip[SCREENWIDTH];
// spanstart holds the start of a plane span; initialized to 0 at start
static int spanstart[SCREENHEIGHT]; // killough 2/8/98
//
// texture mapping
//
static lighttable_t **planezlight;
static fixed_t planeheight;
// killough 2/8/98: make variables static
static fixed_t basexscale, baseyscale;
static fixed_t cachedheight[SCREENHEIGHT];
static fixed_t cacheddistance[SCREENHEIGHT];
static fixed_t cachedxstep[SCREENHEIGHT];
static fixed_t cachedystep[SCREENHEIGHT];
static fixed_t xoffs, yoffs; // killough 2/28/98: flat offsets
fixed_t yslope[SCREENHEIGHT], distscale[SCREENWIDTH];
//
// R_InitPlanes
// Only at game startup.
//
void R_InitPlanes (void)
{
}
//
// R_MapPlane
//
// Uses global vars:
// planeheight
// ds_source
// basexscale
// baseyscale
// viewx
// viewy
// xoffs
// yoffs
//
// BASIC PRIMITIVE
//
static void R_MapPlane(int y, int x1, int x2)
{
angle_t angle;
fixed_t distance, length;
unsigned index;
#ifdef RANGECHECK
if (x2 < x1 || x1<0 || x2>=viewwidth || (unsigned)y>(unsigned)viewheight)
I_Error ("R_MapPlane: %i, %i at %i",x1,x2,y);
#endif
if (planeheight != cachedheight[y])
{
cachedheight[y] = planeheight;
distance = cacheddistance[y] = FixedMul (planeheight, yslope[y]);
ds_xstep = cachedxstep[y] = FixedMul (distance,basexscale);
ds_ystep = cachedystep[y] = FixedMul (distance,baseyscale);
}
else
{
distance = cacheddistance[y];
ds_xstep = cachedxstep[y];
ds_ystep = cachedystep[y];
}
length = FixedMul (distance,distscale[x1]);
angle = (viewangle + xtoviewangle[x1])>>ANGLETOFINESHIFT;
// killough 2/28/98: Add offsets
ds_xfrac = viewx + FixedMul(finecosine[angle], length) + xoffs;
ds_yfrac = -viewy - FixedMul(finesine[angle], length) + yoffs;
if (!(ds_colormap = fixedcolormap))
{
index = distance >> LIGHTZSHIFT;
if (index >= MAXLIGHTZ )
index = MAXLIGHTZ-1;
ds_colormap = planezlight[index];
}
ds_y = y;
ds_x1 = x1;
ds_x2 = x2;
R_DrawSpan();
}
//
// R_ClearPlanes
// At begining of frame.
//
void R_ClearPlanes(void)
{
int i;
angle_t angle;
// opening / clipping determination
for (i=0 ; i<viewwidth ; i++)
floorclip[i] = viewheight, ceilingclip[i] = -1;
for (i=0;i<MAXVISPLANES;i++) // new code -- killough
for (*freehead = visplanes[i], visplanes[i] = NULL; *freehead; )
freehead = &(*freehead)->next;
lastopening = openings;
// texture calculation
memset (cachedheight, 0, sizeof(cachedheight));
// left to right mapping
angle = (viewangle-ANG90)>>ANGLETOFINESHIFT;
// scale will be unit scale at SCREENWIDTH/2 distance
basexscale = FixedDiv (finecosine[angle],centerxfrac);
baseyscale = -FixedDiv (finesine[angle],centerxfrac);
}
// New function, by Lee Killough
static visplane_t *new_visplane(unsigned hash)
{
visplane_t *check = freetail;
if (!check)
check = calloc(1, sizeof *check);
else
if (!(freetail = freetail->next))
freehead = &freetail;
check->next = visplanes[hash];
visplanes[hash] = check;
return check;
}
/*
* R_DupPlane
*
* cph 2003/04/18 - create duplicate of existing visplane and set initial range
*/
visplane_t *R_DupPlane(const visplane_t *pl, int start, int stop)
{
unsigned hash = visplane_hash(pl->picnum, pl->lightlevel, pl->height);
visplane_t *new_pl = new_visplane(hash);
new_pl->height = pl->height;
new_pl->picnum = pl->picnum;
new_pl->lightlevel = pl->lightlevel;
new_pl->xoffs = pl->xoffs; // killough 2/28/98
new_pl->yoffs = pl->yoffs;
new_pl->minx = start;
new_pl->maxx = stop;
memset(new_pl->top, 0xff, sizeof new_pl->top);
return new_pl;
}
//
// R_FindPlane
//
// killough 2/28/98: Add offsets
visplane_t *R_FindPlane(fixed_t height, int picnum, int lightlevel,
fixed_t xoffs, fixed_t yoffs)
{
visplane_t *check;
unsigned hash; // killough
if (picnum == skyflatnum || picnum & PL_SKYFLAT)
height = lightlevel = 0; // killough 7/19/98: most skies map together
// New visplane algorithm uses hash table -- killough
hash = visplane_hash(picnum,lightlevel,height);
for (check=visplanes[hash]; check; check=check->next) // killough
if (height == check->height &&
picnum == check->picnum &&
lightlevel == check->lightlevel &&
xoffs == check->xoffs && // killough 2/28/98: Add offset checks
yoffs == check->yoffs)
return check;
check = new_visplane(hash); // killough
check->height = height;
check->picnum = picnum;
check->lightlevel = lightlevel;
check->minx = viewwidth; // Was SCREENWIDTH -- killough 11/98
check->maxx = -1;
check->xoffs = xoffs; // killough 2/28/98: Save offsets
check->yoffs = yoffs;
memset (check->top, 0xff, sizeof check->top);
return check;
}
//
// R_CheckPlane
//
visplane_t *R_CheckPlane(visplane_t *pl, int start, int stop)
{
int intrl, intrh, unionl, unionh, x;
if (start < pl->minx)
intrl = pl->minx, unionl = start;
else
unionl = pl->minx, intrl = start;
if (stop > pl->maxx)
intrh = pl->maxx, unionh = stop;
else
unionh = pl->maxx, intrh = stop;
for (x=intrl ; x <= intrh && pl->top[x] == 0xffff; x++)
;
if (x > intrh) { /* Can use existing plane; extend range */
pl->minx = unionl; pl->maxx = unionh;
return pl;
} else /* Cannot use existing plane; create a new one */
return R_DupPlane(pl,start,stop);
}
//
// R_MakeSpans
//
static void R_MakeSpans(int x, int t1, int b1, int t2, int b2)
{
for (; t1 < t2 && t1 <= b1; t1++)
R_MapPlane(t1, spanstart[t1], x-1);
for (; b1 > b2 && b1 >= t1; b1--)
R_MapPlane(b1, spanstart[b1] ,x-1);
while (t2 < t1 && t2 <= b2)
spanstart[t2++] = x;
while (b2 > b1 && b2 >= t2)
spanstart[b2--] = x;
}
// New function, by Lee Killough
static void R_DoDrawPlane(visplane_t *pl)
{
register int x;
if (pl->minx <= pl->maxx) {
if (pl->picnum == skyflatnum || pl->picnum & PL_SKYFLAT) { // sky flat
int texture;
angle_t an, flip;
// killough 10/98: allow skies to come from sidedefs.
// Allows scrolling and/or animated skies, as well as
// arbitrary multiple skies per level without having
// to use info lumps.
an = viewangle;
if (pl->picnum & PL_SKYFLAT)
{
// Sky Linedef
const line_t *l = &lines[pl->picnum & ~PL_SKYFLAT];
// Sky transferred from first sidedef
const side_t *s = *l->sidenum + sides;
// Texture comes from upper texture of reference sidedef
texture = texturetranslation[s->toptexture];
// Horizontal offset is turned into an angle offset,
// to allow sky rotation as well as careful positioning.
// However, the offset is scaled very small, so that it
// allows a long-period of sky rotation.
an += s->textureoffset;
// Vertical offset allows careful sky positioning.
dc_texturemid = s->rowoffset - 28*FRACUNIT;
// We sometimes flip the picture horizontally.
//
// Doom always flipped the picture, so we make it optional,
// to make it easier to use the new feature, while to still
// allow old sky textures to be used.
flip = l->special==272 ? 0u : ~0u;
}
else
{ // Normal Doom sky, only one allowed per level
dc_texturemid = skytexturemid; // Default y-offset
texture = skytexture; // Default texture
flip = 0; // Doom flips it
}
/* Sky is always drawn full bright, i.e. colormaps[0] is used.
* Because of this hack, sky is not affected by INVUL inverse mapping.
* Until Boom fixed this. Compat option added in MBF. */
if (comp[comp_skymap] || !(dc_colormap = fixedcolormap))
dc_colormap = fullcolormap; // killough 3/20/98
dc_texheight = textureheight[skytexture]>>FRACBITS; // killough
// proff 09/21/98: Changed for high-res
dc_iscale = FRACUNIT*200/viewheight;
// killough 10/98: Use sky scrolling offset, and possibly flip picture
for (x = pl->minx; (dc_x = x) <= pl->maxx; x++)
if ((dc_yl = pl->top[x]) <= (dc_yh = pl->bottom[x]))
{
dc_source = R_GetColumn(texture, ((an + xtoviewangle[x])^flip) >>
ANGLETOSKYSHIFT);
colfunc();
}
} else { // regular flat
int stop, light;
ds_source = W_CacheLumpNum(firstflat + flattranslation[pl->picnum]);
xoffs = pl->xoffs; // killough 2/28/98: Add offsets
yoffs = pl->yoffs;
planeheight = D_abs(pl->height-viewz);
light = (pl->lightlevel >> LIGHTSEGSHIFT) + extralight;
if (light >= LIGHTLEVELS)
light = LIGHTLEVELS-1;
if (light < 0)
light = 0;
stop = pl->maxx + 1;
planezlight = zlight[light];
pl->top[pl->minx-1] = pl->top[stop] = 0xffff;
for (x = pl->minx ; x <= stop ; x++)
R_MakeSpans(x,pl->top[x-1],pl->bottom[x-1],pl->top[x],pl->bottom[x]);
W_UnlockLumpNum(firstflat + flattranslation[pl->picnum]);
}
}
}
//
// RDrawPlanes
// At the end of each frame.
//
void R_DrawPlanes (void)
{
visplane_t *pl;
int i;
for (i=0;i<MAXVISPLANES;i++)
for (pl=visplanes[i]; pl; pl=pl->next)
R_DoDrawPlane(pl);
}