ref: e19308ee166dd085f7773621471a5fc589af45d4
dir: /sys/src/games/doom/r_draw.c/
// 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. // // $Log:$ // // DESCRIPTION: // The actual span/column drawing functions. // Here find the main potential for optimization, // e.g. inline assembly, different algorithms. // //----------------------------------------------------------------------------- static const char rcsid[] = "$Id: r_draw.c,v 1.4 1997/02/03 16:47:55 b1 Exp $"; #include "doomdef.h" #include "i_system.h" #include "z_zone.h" #include "w_wad.h" #include "r_local.h" // Needs access to LFB (guess what). #include "v_video.h" // State. #include "doomstat.h" // ? #define MAXWIDTH 1120 #define MAXHEIGHT 832 // status bar height at bottom of screen #define SBARHEIGHT 32 // // All drawing to the view buffer is accomplished in this file. // The other refresh files only know about ccordinates, // not the architecture of the frame buffer. // Conveniently, the frame buffer is a linear one, // and we need only the base address, // and the total size == width*height*depth/8., // byte* viewimage; int viewwidth; int scaledviewwidth; int viewheight; int viewwindowx; int viewwindowy; byte* ylookup[MAXHEIGHT]; int columnofs[MAXWIDTH]; // Color tables for different players, // translate a limited part to another // (color ramps used for suit colors). // byte translations[3][256]; // // R_DrawColumn // Source is the top of the column to scale. // lighttable_t* dc_colormap; int dc_x; int dc_yl; int dc_yh; fixed_t dc_iscale; fixed_t dc_texturemid; // first pixel in a column (possibly virtual) byte* dc_source; // just for profiling int dccount; // // A column is a vertical slice/span from a wall texture that, // given the DOOM style restrictions on the view orientation, // will always have constant z depth. // Thus a special case loop for very fast rendering can // be used. It has also been used with Wolfenstein 3D. // void R_DrawColumn (void) { int count; byte* dest; fixed_t frac; fixed_t fracstep; count = dc_yh - dc_yl; // Zero length, column does not exceed a pixel. 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 // Framebuffer destination address. // Use ylookup LUT to avoid multiply with ScreenWidth. // Use columnofs LUT for subwindows? dest = ylookup[dc_yl] + columnofs[dc_x]; // Determine scaling, // which is the only mapping to be done. fracstep = dc_iscale; frac = dc_texturemid + (dc_yl-centery)*fracstep; // Inner loop that does the actual texture mapping, // e.g. a DDA-lile scaling. // This is as fast as it gets. do { // Re-map color indices from wall texture column // using a lighting/special effects LUT. *dest = dc_colormap[dc_source[(frac>>FRACBITS)&127]]; dest += SCREENWIDTH; frac += fracstep; } while (count--); } void R_DrawColumnLow (void) { int count; byte* dest; byte* dest2; fixed_t frac; fixed_t fracstep; count = dc_yh - dc_yl; // Zero length. 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); } // dccount++; #endif // Blocky mode, need to multiply by 2. dc_x <<= 1; dest = ylookup[dc_yl] + columnofs[dc_x]; dest2 = ylookup[dc_yl] + columnofs[dc_x+1]; fracstep = dc_iscale; frac = dc_texturemid + (dc_yl-centery)*fracstep; do { // Hack. Does not work corretly. *dest2 = *dest = dc_colormap[dc_source[(frac>>FRACBITS)&127]]; dest += SCREENWIDTH; dest2 += SCREENWIDTH; frac += fracstep; } while (count--); } // // Spectre/Invisibility. // #define FUZZTABLE 50 #define FUZZOFF (SCREENWIDTH) int fuzzoffset[FUZZTABLE] = { FUZZOFF,-FUZZOFF,FUZZOFF,-FUZZOFF,FUZZOFF,FUZZOFF,-FUZZOFF, FUZZOFF,FUZZOFF,-FUZZOFF,FUZZOFF,FUZZOFF,FUZZOFF,-FUZZOFF, FUZZOFF,FUZZOFF,FUZZOFF,-FUZZOFF,-FUZZOFF,-FUZZOFF,-FUZZOFF, FUZZOFF,-FUZZOFF,-FUZZOFF,FUZZOFF,FUZZOFF,FUZZOFF,FUZZOFF,-FUZZOFF, FUZZOFF,-FUZZOFF,FUZZOFF,FUZZOFF,-FUZZOFF,-FUZZOFF,FUZZOFF, FUZZOFF,-FUZZOFF,-FUZZOFF,-FUZZOFF,-FUZZOFF,FUZZOFF,FUZZOFF, FUZZOFF,FUZZOFF,-FUZZOFF,FUZZOFF,FUZZOFF,-FUZZOFF,FUZZOFF }; int fuzzpos = 0; // // Framebuffer postprocessing. // Creates a fuzzy image by copying pixels // from adjacent ones to left and right. // Used with an all black colormap, this // could create the SHADOW effect, // i.e. spectres and invisible players. // void R_DrawFuzzColumn (void) { int count; byte* dest; fixed_t frac; fixed_t fracstep; // Adjust borders. Low... if (!dc_yl) dc_yl = 1; // .. and high. if (dc_yh == viewheight-1) dc_yh = viewheight - 2; count = dc_yh - dc_yl; // Zero length. if (count < 0) return; #ifdef RANGECHECK if ((unsigned)dc_x >= SCREENWIDTH || dc_yl < 0 || dc_yh >= SCREENHEIGHT) { I_Error ("R_DrawFuzzColumn: %i to %i at %i", dc_yl, dc_yh, dc_x); } #endif // Keep till detailshift bug in blocky mode fixed, // or blocky mode removed. /* WATCOM code if (detailshift) { if (dc_x & 1) { outpw (GC_INDEX,GC_READMAP+(2<<8) ); outp (SC_INDEX+1,12); } else { outpw (GC_INDEX,GC_READMAP); outp (SC_INDEX+1,3); } dest = destview + dc_yl*80 + (dc_x>>1); } else { outpw (GC_INDEX,GC_READMAP+((dc_x&3)<<8) ); outp (SC_INDEX+1,1<<(dc_x&3)); dest = destview + dc_yl*80 + (dc_x>>2); }*/ // Does not work with blocky mode. dest = ylookup[dc_yl] + columnofs[dc_x]; // Looks familiar. fracstep = dc_iscale; frac = dc_texturemid + (dc_yl-centery)*fracstep; // Looks like an attempt at dithering, // using the colormap #6 (of 0-31, a bit // brighter than average). do { // Lookup framebuffer, and retrieve // a pixel that is either one column // left or right of the current one. // Add index from colormap to index. *dest = colormaps[6*256+dest[fuzzoffset[fuzzpos]]]; // Clamp table lookup index. if (++fuzzpos == FUZZTABLE) fuzzpos = 0; dest += SCREENWIDTH; frac += fracstep; } while (count--); } // // R_DrawTranslatedColumn // Used to draw player sprites // with the green colorramp mapped to others. // Could be used with different translation // tables, e.g. the lighter colored version // of the BaronOfHell, the HellKnight, uses // identical sprites, kinda brightened up. // byte* dc_translation; byte* translationtables; void R_DrawTranslatedColumn (void) { int count; byte* dest; fixed_t frac; fixed_t fracstep; 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 // WATCOM VGA specific. /* Keep for fixing. if (detailshift) { if (dc_x & 1) outp (SC_INDEX+1,12); else outp (SC_INDEX+1,3); dest = destview + dc_yl*80 + (dc_x>>1); } else { outp (SC_INDEX+1,1<<(dc_x&3)); dest = destview + dc_yl*80 + (dc_x>>2); }*/ // FIXME. As above. dest = ylookup[dc_yl] + columnofs[dc_x]; // Looks familiar. fracstep = dc_iscale; frac = dc_texturemid + (dc_yl-centery)*fracstep; // Here we do an additional index re-mapping. do { // Translation tables are used // to map certain colorramps to other ones, // used with PLAY sprites. // Thus the "green" ramp of the player 0 sprite // is mapped to gray, red, black/indigo. *dest = dc_colormap[dc_translation[dc_source[frac>>FRACBITS]]]; dest += SCREENWIDTH; frac += fracstep; } while (count--); } // // R_InitTranslationTables // Creates the translation tables to map // the green color ramp to gray, brown, red. // Assumes a given structure of the PLAYPAL. // Could be read from a lump instead. // void R_InitTranslationTables (void) { int i; translationtables = Z_Malloc (256*3+255, PU_STATIC, 0); translationtables = (byte *)(((uintptr)translationtables + 255) & ~255); // translate just the 16 green colors for (i=0 ; i<256 ; i++) { if (i >= 0x70 && i<= 0x7f) { // map green ramp to gray, brown, red translationtables[i] = 0x60 + (i&0xf); translationtables [i+256] = 0x40 + (i&0xf); translationtables [i+512] = 0x20 + (i&0xf); } else { // Keep all other colors as is. translationtables[i] = translationtables[i+256] = translationtables[i+512] = i; } } } // // R_DrawSpan // With DOOM style restrictions on view orientation, // the floors and ceilings consist of horizontal slices // or spans with constant z depth. // However, rotation around the world z axis is possible, // thus this mapping, while simpler and faster than // perspective correct texture mapping, has to traverse // the texture at an angle in all but a few cases. // In consequence, flats are not stored by column (like walls), // and the inner loop has to step in texture space u and v. // int ds_y; int ds_x1; int ds_x2; lighttable_t* ds_colormap; fixed_t ds_xfrac; fixed_t ds_yfrac; fixed_t ds_xstep; fixed_t ds_ystep; // start of a 64*64 tile image byte* ds_source; // just for profiling int dscount; // // Draws the actual span. void R_DrawSpan (void) { fixed_t xfrac; fixed_t yfrac; byte* dest; int count; int spot; #ifdef RANGECHECK if (ds_x2 < ds_x1 || ds_x1<0 || ds_x2>=SCREENWIDTH || (unsigned)ds_y>SCREENHEIGHT) { I_Error( "R_DrawSpan: %i to %i at %i", ds_x1,ds_x2,ds_y); } // dscount++; #endif xfrac = ds_xfrac; yfrac = ds_yfrac; dest = ylookup[ds_y] + columnofs[ds_x1]; // We do not check for zero spans here? count = ds_x2 - ds_x1; do { // Current texture index in u,v. spot = ((yfrac>>(16-6))&(63*64)) + ((xfrac>>16)&63); // Lookup pixel from flat texture tile, // re-index using light/colormap. *dest++ = ds_colormap[ds_source[spot]]; // Next step in u,v. xfrac += ds_xstep; yfrac += ds_ystep; } while (count--); } // // Again.. // void R_DrawSpanLow (void) { fixed_t xfrac; fixed_t yfrac; byte* dest; int count; int spot; #ifdef RANGECHECK if (ds_x2 < ds_x1 || ds_x1<0 || ds_x2>=SCREENWIDTH || (unsigned)ds_y>SCREENHEIGHT) { I_Error( "R_DrawSpan: %i to %i at %i", ds_x1,ds_x2,ds_y); } // dscount++; #endif xfrac = ds_xfrac; yfrac = ds_yfrac; // Blocky mode, need to multiply by 2. ds_x1 <<= 1; ds_x2 <<= 1; dest = ylookup[ds_y] + columnofs[ds_x1]; count = ds_x2 - ds_x1; do { spot = ((yfrac>>(16-6))&(63*64)) + ((xfrac>>16)&63); // Lowres/blocky mode does it twice, // while scale is adjusted appropriately. *dest++ = ds_colormap[ds_source[spot]]; *dest++ = ds_colormap[ds_source[spot]]; xfrac += ds_xstep; yfrac += ds_ystep; } while (count--); } // // R_InitBuffer // Creats lookup tables that avoid // multiplies and other hazzles // for getting the framebuffer address // of a pixel to draw. // void R_InitBuffer ( int width, int height ) { int i; // Handle resize, // e.g. smaller view windows // with border and/or status bar. viewwindowx = (SCREENWIDTH-width) >> 1; // Column offset. For windows. for (i=0 ; i<width ; i++) columnofs[i] = viewwindowx + i; // Samw with base row offset. if (width == SCREENWIDTH) viewwindowy = 0; else viewwindowy = (SCREENHEIGHT-SBARHEIGHT-height) >> 1; // Preclaculate all row offsets. for (i=0 ; i<height ; i++) ylookup[i] = screens[0] + (i+viewwindowy)*SCREENWIDTH; } // // R_FillBackScreen // Fills the back screen with a pattern // for variable screen sizes // Also draws a beveled edge. // void R_FillBackScreen (void) { byte* src; byte* dest; int x; int y; patch_t* patch; // DOOM border patch. char name1[] = "FLOOR7_2"; // DOOM II border patch. char name2[] = "GRNROCK"; char* name; if (scaledviewwidth == 320) return; if ( gamemode == commercial) name = name2; else name = name1; src = W_CacheLumpName (name, PU_CACHE); dest = screens[1]; for (y=0 ; y<SCREENHEIGHT-SBARHEIGHT ; y++) { for (x=0 ; x<SCREENWIDTH/64 ; x++) { memcpy (dest, src+((y&63)<<6), 64); dest += 64; } if (SCREENWIDTH&63) { memcpy (dest, src+((y&63)<<6), SCREENWIDTH&63); dest += (SCREENWIDTH&63); } } patch = W_CacheLumpName ("brdr_t",PU_CACHE); for (x=0 ; x<scaledviewwidth ; x+=8) V_DrawPatch (viewwindowx+x,viewwindowy-8,1,patch); patch = W_CacheLumpName ("brdr_b",PU_CACHE); for (x=0 ; x<scaledviewwidth ; x+=8) V_DrawPatch (viewwindowx+x,viewwindowy+viewheight,1,patch); patch = W_CacheLumpName ("brdr_l",PU_CACHE); for (y=0 ; y<viewheight ; y+=8) V_DrawPatch (viewwindowx-8,viewwindowy+y,1,patch); patch = W_CacheLumpName ("brdr_r",PU_CACHE); for (y=0 ; y<viewheight ; y+=8) V_DrawPatch (viewwindowx+scaledviewwidth,viewwindowy+y,1,patch); // Draw beveled edge. V_DrawPatch (viewwindowx-8, viewwindowy-8, 1, W_CacheLumpName ("brdr_tl",PU_CACHE)); V_DrawPatch (viewwindowx+scaledviewwidth, viewwindowy-8, 1, W_CacheLumpName ("brdr_tr",PU_CACHE)); V_DrawPatch (viewwindowx-8, viewwindowy+viewheight, 1, W_CacheLumpName ("brdr_bl",PU_CACHE)); V_DrawPatch (viewwindowx+scaledviewwidth, viewwindowy+viewheight, 1, W_CacheLumpName ("brdr_br",PU_CACHE)); } // // Copy a screen buffer. // void R_VideoErase ( unsigned ofs, int count ) { // LFB copy. // This might not be a good idea if memcpy // is not optiomal, e.g. byte by byte on // a 32bit CPU, as GNU GCC/Linux libc did // at one point. memcpy (screens[0]+ofs, screens[1]+ofs, count); } // // R_DrawViewBorder // Draws the border around the view // for different size windows? // void V_MarkRect ( int x, int y, int width, int height ); void R_DrawViewBorder (void) { int top; int side; int ofs; int i; if (scaledviewwidth == SCREENWIDTH) return; top = ((SCREENHEIGHT-SBARHEIGHT)-viewheight)/2; side = (SCREENWIDTH-scaledviewwidth)/2; // copy top and one line of left side R_VideoErase (0, top*SCREENWIDTH+side); // copy one line of right side and bottom ofs = (viewheight+top)*SCREENWIDTH-side; R_VideoErase (ofs, top*SCREENWIDTH+side); // copy sides using wraparound ofs = top*SCREENWIDTH + SCREENWIDTH-side; side <<= 1; for (i=1 ; i<viewheight ; i++) { R_VideoErase (ofs, side); ofs += SCREENWIDTH; } // ? V_MarkRect (0,0,SCREENWIDTH, SCREENHEIGHT-SBARHEIGHT); }