ref: 13a26589a3f292ef3f6dce941de68ea7b33746b0
dir: /src/heretic/r_plane.c/
// // Copyright(C) 1993-1996 Id Software, Inc. // Copyright(C) 1993-2008 Raven Software // Copyright(C) 2005-2014 Simon Howard // // 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. // // R_planes.c #include <stdlib.h> #include "doomdef.h" #include "deh_str.h" #include "i_system.h" #include "r_local.h" planefunction_t floorfunc, ceilingfunc; // // sky mapping // int skyflatnum; int skytexture; int skytexturemid; fixed_t skyiscale; // // opening // visplane_t visplanes[MAXVISPLANES], *lastvisplane; visplane_t *floorplane, *ceilingplane; short openings[MAXOPENINGS], *lastopening; // // clip values are the solid pixel bounding the range // floorclip starts out SCREENHEIGHT // ceilingclip starts out -1 // short floorclip[SCREENWIDTH]; short ceilingclip[SCREENWIDTH]; // // spanstart holds the start of a plane span // initialized to 0 at start // int spanstart[SCREENHEIGHT]; int spanstop[SCREENHEIGHT]; // // texture mapping // lighttable_t **planezlight; fixed_t planeheight; fixed_t yslope[SCREENHEIGHT]; fixed_t distscale[SCREENWIDTH]; fixed_t basexscale, baseyscale; fixed_t cachedheight[SCREENHEIGHT]; fixed_t cacheddistance[SCREENHEIGHT]; fixed_t cachedxstep[SCREENHEIGHT]; fixed_t cachedystep[SCREENHEIGHT]; /* ================ = = R_InitSkyMap = = Called whenever the view size changes = ================ */ void R_InitSkyMap(void) { skyflatnum = R_FlatNumForName(DEH_String("F_SKY1")); skytexturemid = 200 * FRACUNIT; skyiscale = FRACUNIT; } /* ==================== = = R_InitPlanes = = Only at game startup ==================== */ void R_InitPlanes(void) { } /* ================ = = R_MapPlane = global vars: planeheight ds_source basexscale baseyscale viewx viewy BASIC PRIMITIVE ================ */ 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 > 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; ds_xfrac = viewx + FixedMul(finecosine[angle], length); ds_yfrac = -viewy - FixedMul(finesine[angle], length); if (fixedcolormap) ds_colormap = fixedcolormap; else { index = distance >> LIGHTZSHIFT; if (index >= MAXLIGHTZ) index = MAXLIGHTZ - 1; ds_colormap = planezlight[index]; } ds_y = y; ds_x1 = x1; ds_x2 = x2; spanfunc(); // high or low detail } //============================================================================= /* ==================== = = 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; } lastvisplane = visplanes; lastopening = openings; // // texture calculation // memset(cachedheight, 0, sizeof(cachedheight)); angle = (viewangle - ANG90) >> ANGLETOFINESHIFT; // left to right mapping // scale will be unit scale at SCREENWIDTH/2 distance basexscale = FixedDiv(finecosine[angle], centerxfrac); baseyscale = -FixedDiv(finesine[angle], centerxfrac); } /* =============== = = R_FindPlane = =============== */ visplane_t *R_FindPlane(fixed_t height, int picnum, int lightlevel, int special) { visplane_t *check; if (picnum == skyflatnum) { // all skies map together height = 0; lightlevel = 0; } for (check = visplanes; check < lastvisplane; check++) { if (height == check->height && picnum == check->picnum && lightlevel == check->lightlevel && special == check->special) break; } if (check < lastvisplane) { return (check); } if (lastvisplane - visplanes == MAXVISPLANES) { I_Error("R_FindPlane: no more visplanes"); } lastvisplane++; check->height = height; check->picnum = picnum; check->lightlevel = lightlevel; check->special = special; check->minx = SCREENWIDTH; check->maxx = -1; 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; int unionl, unionh; int 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; x++) if (pl->top[x] != 0xff) break; if (x > intrh) { pl->minx = unionl; pl->maxx = unionh; return pl; // use the same one } // make a new visplane lastvisplane->height = pl->height; lastvisplane->picnum = pl->picnum; lastvisplane->lightlevel = pl->lightlevel; lastvisplane->special = pl->special; pl = lastvisplane++; pl->minx = start; pl->maxx = stop; memset(pl->top, 0xff, sizeof(pl->top)); return pl; } //============================================================================= /* ================ = = R_MakeSpans = ================ */ void R_MakeSpans(int x, int t1, int b1, int t2, int b2) { while (t1 < t2 && t1 <= b1) { R_MapPlane(t1, spanstart[t1], x - 1); t1++; } while (b1 > b2 && b1 >= t1) { R_MapPlane(b1, spanstart[b1], x - 1); b1--; } while (t2 < t1 && t2 <= b2) { spanstart[t2] = x; t2++; } while (b2 > b1 && b2 >= t2) { spanstart[b2] = x; b2--; } } /* ================ = = R_DrawPlanes = = At the end of each frame ================ */ void R_DrawPlanes(void) { visplane_t *pl; int light; int x, stop; int lumpnum; int angle; byte *tempSource; byte *dest; int count; fixed_t frac, fracstep; extern byte *ylookup[MAXHEIGHT]; extern int columnofs[MAXWIDTH]; #ifdef RANGECHECK if (ds_p - drawsegs > MAXDRAWSEGS) I_Error("R_DrawPlanes: drawsegs overflow (%td)", ds_p - drawsegs); if (lastvisplane - visplanes > MAXVISPLANES) I_Error("R_DrawPlanes: visplane overflow (%td)", lastvisplane - visplanes); if (lastopening - openings > MAXOPENINGS) I_Error("R_DrawPlanes: opening overflow (%td)", lastopening - openings); #endif for (pl = visplanes; pl < lastvisplane; pl++) { if (pl->minx > pl->maxx) continue; // // sky flat // if (pl->picnum == skyflatnum) { dc_iscale = skyiscale; dc_colormap = colormaps; // sky is allways drawn full bright dc_texturemid = skytexturemid; for (x = pl->minx; x <= pl->maxx; x++) { dc_yl = pl->top[x]; dc_yh = pl->bottom[x]; if (dc_yl <= dc_yh) { angle = (viewangle + xtoviewangle[x]) >> ANGLETOSKYSHIFT; dc_x = x; dc_source = R_GetColumn(skytexture, angle); count = dc_yh - dc_yl; if (count < 0) return; #ifdef RANGECHECK if ((unsigned) dc_x >= SCREENWIDTH || dc_yl < 0 || dc_yh >= SCREENHEIGHT) I_Error("R_DrawColumn: %i to %i at %i", dc_yl, dc_yh, dc_x); #endif dest = ylookup[dc_yl] + columnofs[dc_x]; fracstep = 1; frac = (dc_texturemid >> FRACBITS) + (dc_yl - centery); do { *dest = dc_source[frac]; dest += SCREENWIDTH; frac += fracstep; } while (count--); // colfunc (); } } continue; } // // regular flat // lumpnum = firstflat + flattranslation[pl->picnum]; tempSource = W_CacheLumpNum(lumpnum, PU_STATIC); switch (pl->special) { case 25: case 26: case 27: case 28: case 29: // Scroll_North ds_source = tempSource; break; case 20: case 21: case 22: case 23: case 24: // Scroll_East ds_source = tempSource + ((63 - ((leveltime >> 1) & 63)) << (pl->special - 20) & 63); //ds_source = tempSource+((leveltime>>1)&63); break; case 30: case 31: case 32: case 33: case 34: // Scroll_South ds_source = tempSource; break; case 35: case 36: case 37: case 38: case 39: // Scroll_West ds_source = tempSource; break; case 4: // Scroll_EastLavaDamage ds_source = tempSource + (((63 - ((leveltime >> 1) & 63)) << 3) & 63); break; default: ds_source = tempSource; } planeheight = abs(pl->height - viewz); light = (pl->lightlevel >> LIGHTSEGSHIFT) + extralight; if (light >= LIGHTLEVELS) light = LIGHTLEVELS - 1; if (light < 0) light = 0; planezlight = zlight[light]; pl->top[pl->maxx + 1] = 0xff; pl->top[pl->minx - 1] = 0xff; stop = pl->maxx + 1; 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_ReleaseLumpNum(lumpnum); } }