SRB2/src/r_splats.c
2023-09-08 17:43:55 -03:00

603 lines
13 KiB
C

// SONIC ROBO BLAST 2
//-----------------------------------------------------------------------------
// Copyright (C) 1998-2000 by DooM Legacy Team.
// Copyright (C) 1999-2023 by Sonic Team Junior.
//
// This program is free software distributed under the
// terms of the GNU General Public License, version 2.
// See the 'LICENSE' file for more details.
//-----------------------------------------------------------------------------
/// \file r_splats.c
/// \brief Floor splats
#include "r_draw.h"
#include "r_fps.h"
#include "r_main.h"
#include "r_splats.h"
#include "r_bsp.h"
#include "p_local.h"
#include "p_slopes.h"
#include "w_wad.h"
#include "z_zone.h"
struct rastery_s *prastertab; // for ASM code
static struct rastery_s rastertab[MAXVIDHEIGHT];
static void prepare_rastertab(void);
// ==========================================================================
// FLOOR SPLATS
// ==========================================================================
static void R_RasterizeFloorSplat(floorsplat_t *pSplat, vector2_t *verts, vissprite_t *vis);
static void rasterize_segment_tex(INT32 x1, INT32 y1, INT32 x2, INT32 y2, INT32 tv1, INT32 tv2, INT32 tc, INT32 dir)
{
{
fixed_t xs, xe, count;
fixed_t dx0, dx1;
if (y1 == y2)
return;
if (y2 > y1)
{
count = (y2-y1)+1;
dx0 = FixedDiv((x2-x1)<<FRACBITS, count<<FRACBITS);
dx1 = FixedDiv((tv2-tv1)<<FRACBITS, count<<FRACBITS);
xs = x1 << FRACBITS;
xe = tv1 << FRACBITS;
tc <<= FRACBITS;
if (dir == 0)
{
for (;;)
{
rastertab[y1].maxx = xs;
rastertab[y1].tx2 = xe;
rastertab[y1].ty2 = tc;
xs += dx0;
xe += dx1;
y1++;
if (count-- < 1) break;
}
}
else
{
for (;;)
{
rastertab[y1].maxx = xs;
rastertab[y1].tx2 = tc;
rastertab[y1].ty2 = xe;
xs += dx0;
xe += dx1;
y1++;
if (count-- < 1) break;
}
}
}
else
{
count = (y1-y2)+1;
dx0 = FixedDiv((x1-x2)<<FRACBITS, count<<FRACBITS);
dx1 = FixedDiv((tv1-tv2)<<FRACBITS, count<<FRACBITS);
xs = x2 << FRACBITS;
xe = tv2 << FRACBITS;
tc <<= FRACBITS;
if (dir == 0)
{
for (;;)
{
rastertab[y2].minx = xs;
rastertab[y2].tx1 = xe;
rastertab[y2].ty1 = tc;
xs += dx0;
xe += dx1;
y2++;
if (count-- < 1) break;
}
}
else
{
for (;;)
{
rastertab[y2].minx = xs;
rastertab[y2].tx1 = tc;
rastertab[y2].ty1 = xe;
xs += dx0;
xe += dx1;
y2++;
if (count-- < 1) break;
}
}
}
}
}
void R_DrawFloorSplat(vissprite_t *spr)
{
floorsplat_t splat;
mobj_t *mobj = spr->mobj;
fixed_t tr_x, tr_y, rot_x, rot_y, rot_z;
vector3_t *v3d;
vector2_t v2d[4];
vector2_t rotated[4];
fixed_t x, y;
fixed_t w, h;
angle_t angle, splatangle;
fixed_t ca, sa;
fixed_t xscale, yscale;
fixed_t xoffset, yoffset;
fixed_t leftoffset, topoffset;
INT32 i;
boolean hflip = (spr->xiscale < 0);
boolean vflip = (spr->cut & SC_VFLIP);
UINT8 flipflags = 0;
renderflags_t renderflags = spr->renderflags;
if (hflip)
flipflags |= PICFLAGS_XFLIP;
if (vflip)
flipflags |= PICFLAGS_YFLIP;
if (!mobj || P_MobjWasRemoved(mobj))
return;
Patch_GenerateFlat(spr->patch, flipflags);
splat.pic = spr->patch->flats[flipflags];
if (splat.pic == NULL)
return;
splat.mobj = mobj;
splat.width = spr->patch->width;
splat.height = spr->patch->height;
splat.scale = mobj->scale;
if (mobj->skin && ((skin_t *)mobj->skin)->flags & SF_HIRES)
splat.scale = FixedMul(splat.scale, ((skin_t *)mobj->skin)->highresscale);
if (spr->rotateflags & SRF_3D || renderflags & RF_NOSPLATBILLBOARD)
splatangle = mobj->angle;
else
splatangle = spr->viewpoint.angle;
if (!(spr->cut & SC_ISROTATED))
splatangle += mobj->spriteroll;
splat.angle = -splatangle;
splat.angle += ANGLE_90;
topoffset = spr->spriteyoffset;
leftoffset = spr->spritexoffset;
if (hflip)
leftoffset = ((splat.width * FRACUNIT) - leftoffset);
xscale = spr->spritexscale;
yscale = spr->spriteyscale;
splat.xscale = FixedMul(splat.scale, xscale);
splat.yscale = FixedMul(splat.scale, yscale);
xoffset = FixedMul(leftoffset, splat.xscale);
yoffset = FixedMul(topoffset, splat.yscale);
x = mobj->x;
y = mobj->y;
w = (splat.width * splat.xscale);
h = (splat.height * splat.yscale);
splat.x = x;
splat.y = y;
splat.z = spr->pz;
splat.slope = NULL;
// Set positions
// 3--2
// | |
// 0--1
splat.verts[0].x = w - xoffset;
splat.verts[0].y = yoffset;
splat.verts[1].x = -xoffset;
splat.verts[1].y = yoffset;
splat.verts[2].x = -xoffset;
splat.verts[2].y = -h + yoffset;
splat.verts[3].x = w - xoffset;
splat.verts[3].y = -h + yoffset;
angle = -splat.angle>>ANGLETOFINESHIFT;
ca = FINECOSINE(angle);
sa = FINESINE(angle);
// Rotate
for (i = 0; i < 4; i++)
{
rotated[i].x = FixedMul(splat.verts[i].x, ca) - FixedMul(splat.verts[i].y, sa);
rotated[i].y = FixedMul(splat.verts[i].x, sa) + FixedMul(splat.verts[i].y, ca);
}
if (renderflags & (RF_SLOPESPLAT | RF_OBJECTSLOPESPLAT))
{
pslope_t *standingslope = mobj->standingslope; // The slope that the object is standing on.
// The slope that was defined for the sprite.
if (renderflags & RF_SLOPESPLAT)
splat.slope = mobj->floorspriteslope;
if (standingslope && (renderflags & RF_OBJECTSLOPESPLAT))
splat.slope = standingslope;
}
// Translate
for (i = 0; i < 4; i++)
{
tr_x = rotated[i].x + mobj->x;
tr_y = rotated[i].y + mobj->y;
if (splat.slope)
{
rot_z = P_GetSlopeZAt(splat.slope, tr_x, tr_y);
splat.verts[i].z = rot_z;
}
else
splat.verts[i].z = splat.z;
splat.verts[i].x = tr_x;
splat.verts[i].y = tr_y;
}
angle = spr->viewpoint.angle >> ANGLETOFINESHIFT;
ca = FINECOSINE(angle);
sa = FINESINE(angle);
// Project
for (i = 0; i < 4; i++)
{
v3d = &splat.verts[i];
// transform the origin point
tr_x = v3d->x - spr->viewpoint.x;
tr_y = v3d->y - spr->viewpoint.y;
// rotation around vertical y axis
rot_x = FixedMul(tr_x - (mobj->x - x), sa) - FixedMul(tr_y - (mobj->y - y), ca);
rot_y = FixedMul(tr_x - (mobj->x - x), ca) + FixedMul(tr_y - (mobj->y - y), sa);
rot_z = v3d->z - spr->viewpoint.z;
if (rot_y < FRACUNIT)
return;
// note: y from view above of map, is distance far away
xscale = FixedDiv(projection, rot_y);
yscale = -FixedDiv(projectiony, rot_y);
// projection
v2d[i].x = (centerxfrac + FixedMul(rot_x, xscale))>>FRACBITS;
v2d[i].y = (centeryfrac + FixedMul(rot_z, yscale))>>FRACBITS;
}
R_RasterizeFloorSplat(&splat, v2d, spr);
}
// --------------------------------------------------------------------------
// Rasterize the four edges of a floor splat polygon,
// fill the polygon with linear interpolation, call span drawer for each
// scan line
// --------------------------------------------------------------------------
static void R_RasterizeFloorSplat(floorsplat_t *pSplat, vector2_t *verts, vissprite_t *vis)
{
// rasterizing
INT32 miny = viewheight + 1, maxy = 0;
INT32 y, x1, ry1, x2, y2, i;
fixed_t offsetx = 0, offsety = 0;
fixed_t planeheight = 0;
fixed_t step;
int spanfunctype;
#define RASTERPARAMS(vnum1, vnum2, tv1, tv2, tc, dir) \
x1 = verts[vnum1].x; \
ry1 = verts[vnum1].y; \
x2 = verts[vnum2].x; \
y2 = verts[vnum2].y; \
if (y2 > ry1) \
step = FixedDiv(x2-x1, y2-ry1+1); \
else if (y2 == ry1) \
step = 0; \
else \
step = FixedDiv(x2-x1, ry1-y2+1); \
if (ry1 < 0) { \
if (step) { \
x1 <<= FRACBITS; \
x1 += (-ry1)*step; \
x1 >>= FRACBITS; \
} \
ry1 = 0; \
} \
if (ry1 >= vid.height) { \
if (step) { \
x1 <<= FRACBITS; \
x1 -= (vid.height-1-ry1)*step; \
x1 >>= FRACBITS; \
} \
ry1 = vid.height - 1; \
} \
if (y2 < 0) { \
if (step) { \
x2 <<= FRACBITS; \
x2 -= (-y2)*step; \
x2 >>= FRACBITS; \
} \
y2 = 0; \
} \
if (y2 >= vid.height) { \
if (step) { \
x2 <<= FRACBITS; \
x2 += (vid.height-1-y2)*step; \
x2 >>= FRACBITS; \
} \
y2 = vid.height - 1; \
} \
rasterize_segment_tex(x1, ry1, x2, y2, tv1, tv2, tc, dir); \
if (ry1 < miny) \
miny = ry1; \
if (ry1 > maxy) \
maxy = ry1;
ds_source = (UINT8 *)pSplat->pic;
ds_flatwidth = pSplat->width;
ds_flatheight = pSplat->height;
ds_powersoftwo = ds_solidcolor = false;
if (R_CheckSolidColorFlat())
ds_solidcolor = true;
else if (R_CheckPowersOfTwo())
{
R_SetFlatVars(ds_flatwidth * ds_flatheight);
ds_powersoftwo = true;
}
if (pSplat->slope)
{
R_SetTiltedSpan(0);
R_SetScaledSlopePlane(pSplat->slope, vis->viewpoint.x, vis->viewpoint.y, vis->viewpoint.z, pSplat->xscale, pSplat->yscale, -pSplat->verts[0].x, pSplat->verts[0].y, vis->viewpoint.angle, pSplat->angle);
R_CalculateSlopeVectors();
}
else if (!ds_solidcolor)
{
planeheight = abs(pSplat->z - vis->viewpoint.z);
if (pSplat->angle)
{
memset(cachedheight, 0, sizeof(cachedheight));
// Add the view offset, rotated by the plane angle.
fixed_t a = -pSplat->verts[0].x + vis->viewpoint.x;
fixed_t b = -pSplat->verts[0].y + vis->viewpoint.y;
angle_t angle = (pSplat->angle >> ANGLETOFINESHIFT);
offsetx = FixedMul(a, FINECOSINE(angle)) - FixedMul(b, FINESINE(angle));
offsety = -FixedMul(a, FINESINE(angle)) - FixedMul(b, FINECOSINE(angle));
}
else
{
offsetx = vis->viewpoint.x - pSplat->verts[0].x;
offsety = pSplat->verts[0].y - vis->viewpoint.y;
}
}
ds_colormap = vis->colormap;
ds_translation = R_GetSpriteTranslation(vis);
if (ds_translation == NULL)
ds_translation = colormaps;
if (vis->extra_colormap)
{
if (!ds_colormap)
ds_colormap = vis->extra_colormap->colormap;
else
ds_colormap = &vis->extra_colormap->colormap[ds_colormap - colormaps];
}
ds_transmap = vis->transmap;
// Determine which R_DrawWhatever to use
// Solid color
if (ds_solidcolor)
{
UINT16 px = *(UINT16 *)ds_source;
// Uh, it's not visible.
if (!(px & 0xFF00))
return;
// Pixel color is contained in the lower 8 bits (upper 8 are the opacity), so advance the pointer
ds_source++;
if (pSplat->slope)
{
if (ds_transmap)
spanfunctype = SPANDRAWFUNC_TILTEDTRANSSOLID;
else
spanfunctype = SPANDRAWFUNC_TILTEDSOLID;
}
else
{
if (ds_transmap)
spanfunctype = SPANDRAWFUNC_TRANSSOLID;
else
spanfunctype = SPANDRAWFUNC_SOLID;
}
}
// Transparent
else if (ds_transmap)
{
if (pSplat->slope)
spanfunctype = SPANDRAWFUNC_TILTEDTRANSSPRITE;
else
spanfunctype = SPANDRAWFUNC_TRANSSPRITE;
}
// Opaque
else
{
if (pSplat->slope)
spanfunctype = SPANDRAWFUNC_TILTEDSPRITE;
else
spanfunctype = SPANDRAWFUNC_SPRITE;
}
if (ds_powersoftwo || ds_solidcolor)
spanfunc = spanfuncs[spanfunctype];
else
spanfunc = spanfuncs_npo2[spanfunctype];
prepare_rastertab();
// do segment a -> top of texture
RASTERPARAMS(3,2,0,pSplat->width-1,0,0);
// do segment b -> right side of texture
RASTERPARAMS(2,1,0,pSplat->width-1,pSplat->height-1,0);
// do segment c -> bottom of texture
RASTERPARAMS(1,0,pSplat->width-1,0,pSplat->height-1,0);
// do segment d -> left side of texture
RASTERPARAMS(0,3,pSplat->width-1,0,0,1);
if (maxy >= vid.height)
maxy = vid.height-1;
for (y = miny; y <= maxy; y++)
{
boolean cliptab[MAXVIDWIDTH+1];
x1 = rastertab[y].minx>>FRACBITS;
x2 = rastertab[y].maxx>>FRACBITS;
if (x1 > x2)
{
INT32 swap = x1;
x1 = x2;
x2 = swap;
}
if (x1 == INT16_MIN || x2 == INT16_MAX)
continue;
if (x1 < 0)
x1 = 0;
if (x2 >= viewwidth)
x2 = viewwidth - 1;
if (x1 >= viewwidth || x2 < 0)
continue;
for (i = x1; i <= x2; i++)
cliptab[i] = (y >= mfloorclip[i] || y <= mceilingclip[i]);
// clip left
while (cliptab[x1])
{
x1++;
if (x1 >= viewwidth)
break;
}
// clip right
i = x2;
while (i > x1)
{
if (cliptab[i])
x2 = i-1;
i--;
if (i < 0)
break;
}
if (x2 < x1)
continue;
if (!ds_solidcolor && !pSplat->slope)
{
fixed_t xstep, ystep;
fixed_t distance, span;
angle_t angle = (vis->viewpoint.angle + pSplat->angle)>>ANGLETOFINESHIFT;
angle_t planecos = FINECOSINE(angle);
angle_t planesin = FINESINE(angle);
if (planeheight != cachedheight[y])
{
cachedheight[y] = planeheight;
distance = cacheddistance[y] = FixedMul(planeheight, yslope[y]);
span = abs(centery - y);
if (span) // Don't divide by zero
{
xstep = FixedMul(planesin, planeheight) / span;
ystep = FixedMul(planecos, planeheight) / span;
}
else
xstep = ystep = FRACUNIT;
cachedxstep[y] = xstep;
cachedystep[y] = ystep;
}
else
{
distance = cacheddistance[y];
xstep = cachedxstep[y];
ystep = cachedystep[y];
}
ds_xstep = FixedDiv(xstep, pSplat->xscale);
ds_ystep = FixedDiv(ystep, pSplat->yscale);
ds_xfrac = FixedDiv(offsetx + FixedMul(planecos, distance) + (x1 - centerx) * xstep, pSplat->xscale);
ds_yfrac = FixedDiv(offsety - FixedMul(planesin, distance) + (x1 - centerx) * ystep, pSplat->yscale);
}
ds_y = y;
ds_x1 = x1;
ds_x2 = x2;
spanfunc();
rastertab[y].minx = INT32_MAX;
rastertab[y].maxx = INT32_MIN;
}
if (!ds_solidcolor && pSplat->angle && !pSplat->slope)
memset(cachedheight, 0, sizeof(cachedheight));
}
static void prepare_rastertab(void)
{
INT32 i;
prastertab = rastertab;
for (i = 0; i < vid.height; i++)
{
rastertab[i].minx = INT32_MAX;
rastertab[i].maxx = INT32_MIN;
}
}