ref: 2c0d5e026f50ae4f2a069b882a598e9a8a4d553b
dir: /draw.c/
// WL_DRAW.C #include "WL_DEF.H" #include <DOS.H> #pragma hdrstop //#define DEBUGWALLS //#define DEBUGTICS /* ============================================================================= LOCAL CONSTANTS ============================================================================= */ // the door is the last picture before the sprites #define DOORWALL (PMSpriteStart-8) #define ACTORSIZE 0x4000 /* ============================================================================= GLOBAL VARIABLES ============================================================================= */ #ifdef DEBUGWALLS u16int screenloc[3]= {0,0,0}; #else u16int screenloc[3]= {PAGE1START,PAGE2START,PAGE3START}; #endif u16int freelatch = FREESTART; s32int lasttimecount; s32int frameon; u16int wallheight[MAXVIEWWIDTH]; s32int tileglobal = TILEGLOBAL; s32int mindist = MINDIST; // // math tables // s16int pixelangle[MAXVIEWWIDTH]; s32int far finetangent[FINEANGLES/4]; s32int far sintable[ANGLES+ANGLES/4],far *costable = sintable+(ANGLES/4); // // refresh variables // s32int viewx,viewy; // the focal point s16int viewangle; s32int viewsin,viewcos; s32int FixedByFrac (s32int a, s32int b); void TransformActor (objtype *ob); void BuildTables (void); void ClearScreen (void); s16int CalcRotate (objtype *ob); void DrawScaleds (void); void CalcTics (void); void FixOfs (void); void ThreeDRefresh (void); // // wall optimization variables // s16int lastside; // true for vertical s32int lastintercept; s16int lasttilehit; // // ray tracing variables // s16int focaltx,focalty,viewtx,viewty; s16int midangle,angle; u16int xpartial,ypartial; u16int xpartialup,xpartialdown,ypartialup,ypartialdown; u16int xinttile,yinttile; u16int tilehit; u16int pixx; s16int xtile,ytile; s16int xtilestep,ytilestep; s32int xintercept,yintercept; s32int xstep,ystep; s16int horizwall[MAXWALLTILES],vertwall[MAXWALLTILES]; /* ============================================================================= LOCAL VARIABLES ============================================================================= */ void AsmRefresh (void); // in WL_DR_A.ASM /* ============================================================================ 3 - D DEFINITIONS ============================================================================ */ //========================================================================== /* ======================== = = FixedByFrac = = multiply a 16/16 bit, 2's complement fixed point number by a 16 bit = fraction, passed as a signed magnitude 32 bit number = ======================== */ #pragma warn -rvl // I stick the return value in with ASMs s32int FixedByFrac (s32int a, s32int b) { // // setup // asm mov si,[WORD PTR b+2] // sign of result = sign of fraction asm mov ax,[WORD PTR a] asm mov cx,[WORD PTR a+2] asm or cx,cx asm jns aok: // negative? asm neg cx asm neg ax asm sbb cx,0 asm xor si,0x8000 // toggle sign of result aok: // // multiply cx:ax by bx // asm mov bx,[WORD PTR b] asm mul bx // fraction*fraction asm mov di,dx // di is low word of result asm mov ax,cx // asm mul bx // units*fraction asm add ax,di asm adc dx,0 // // put result dx:ax in 2's complement // asm test si,0x8000 // is the result negative? asm jz ansok: asm neg dx asm neg ax asm sbb dx,0 ansok:; } #pragma warn +rvl //========================================================================== /* ======================== = = TransformActor = = Takes paramaters: = gx,gy : globalx/globaly of point = = globals: = viewx,viewy : point of view = viewcos,viewsin : sin/cos of viewangle = scale : conversion from global value to screen value = = sets: = screenx,transx,transy,screenheight: projected edge location and size = ======================== */ // // transform actor // void TransformActor (objtype *ob) { s16int ratio; s32int gx,gy,gxt,gyt,nx,ny; s32int temp; // // translate point to view centered coordinates // gx = ob->x-viewx; gy = ob->y-viewy; // // calculate newx // gxt = FixedByFrac(gx,viewcos); gyt = FixedByFrac(gy,viewsin); nx = gxt-gyt-ACTORSIZE; // fudge the shape forward a bit, because // the midpoint could put parts of the shape // into an adjacent wall // // calculate newy // gxt = FixedByFrac(gx,viewsin); gyt = FixedByFrac(gy,viewcos); ny = gyt+gxt; // // calculate perspective ratio // ob->transx = nx; ob->transy = ny; if (nx<mindist) // too close, don't overflow the divide { ob->viewheight = 0; return; } ob->viewx = centerx + ny*scale/nx; // DEBUG: use assembly divide // // calculate height (heightnumerator/(nx>>8)) // asm mov ax,[WORD PTR heightnumerator] asm mov dx,[WORD PTR heightnumerator+2] asm idiv [WORD PTR nx+1] // nx>>8 asm mov [WORD PTR temp],ax asm mov [WORD PTR temp+2],dx ob->viewheight = temp; } //========================================================================== /* ======================== = = TransformTile = = Takes paramaters: = tx,ty : tile the object is centered in = = globals: = viewx,viewy : point of view = viewcos,viewsin : sin/cos of viewangle = scale : conversion from global value to screen value = = sets: = screenx,transx,transy,screenheight: projected edge location and size = = Returns true if the tile is withing getting distance = ======================== */ int TransformTile (s16int tx, s16int ty, s16int *dispx, s16int *dispheight) { s16int ratio; s32int gx,gy,gxt,gyt,nx,ny; s32int temp; // // translate point to view centered coordinates // gx = ((s32int)tx<<TILESHIFT)+0x8000-viewx; gy = ((s32int)ty<<TILESHIFT)+0x8000-viewy; // // calculate newx // gxt = FixedByFrac(gx,viewcos); gyt = FixedByFrac(gy,viewsin); nx = gxt-gyt-0x2000; // 0x2000 is size of object // // calculate newy // gxt = FixedByFrac(gx,viewsin); gyt = FixedByFrac(gy,viewcos); ny = gyt+gxt; // // calculate perspective ratio // if (nx<mindist) // too close, don't overflow the divide { *dispheight = 0; return false; } *dispx = centerx + ny*scale/nx; // DEBUG: use assembly divide // // calculate height (heightnumerator/(nx>>8)) // asm mov ax,[WORD PTR heightnumerator] asm mov dx,[WORD PTR heightnumerator+2] asm idiv [WORD PTR nx+1] // nx>>8 asm mov [WORD PTR temp],ax asm mov [WORD PTR temp+2],dx *dispheight = temp; // // see if it should be grabbed // if (nx<TILEGLOBAL && ny>-TILEGLOBAL/2 && ny<TILEGLOBAL/2) return true; else return false; } //========================================================================== /* ==================== = = CalcHeight = = Calculates the height of xintercept,yintercept from viewx,viewy = ==================== */ #pragma warn -rvl // I stick the return value in with ASMs s16int CalcHeight (void) { s16int transheight; s16int ratio; s32int gxt,gyt,nx,ny; s32int gx,gy; gx = xintercept-viewx; gxt = FixedByFrac(gx,viewcos); gy = yintercept-viewy; gyt = FixedByFrac(gy,viewsin); nx = gxt-gyt; // // calculate perspective ratio (heightnumerator/(nx>>8)) // if (nx<mindist) nx=mindist; // don't let divide overflow asm mov ax,[WORD PTR heightnumerator] asm mov dx,[WORD PTR heightnumerator+2] asm idiv [WORD PTR nx+1] // nx>>8 } //========================================================================== /* =================== = = ScalePost = =================== */ s32int postsource; u16int postx; u16int postwidth; void near ScalePost (void) // VGA version { asm mov ax,SCREENSEG asm mov es,ax asm mov bx,[postx] asm shl bx,1 asm mov bp,WORD PTR [wallheight+bx] // fractional height (low 3 bits frac) asm and bp,0xfff8 // bp = heightscaler*4 asm shr bp,1 asm cmp bp,[maxscaleshl2] asm jle heightok asm mov bp,[maxscaleshl2] heightok: asm add bp,OFFSET fullscalefarcall // // scale a byte wide strip of wall // asm mov bx,[postx] asm mov di,bx asm shr di,2 // X in bytes asm add di,[bufferofs] asm and bx,3 asm shl bx,3 // bx = pixel*8+pixwidth asm add bx,[postwidth] asm mov al,BYTE PTR [mapmasks1-1+bx] // -1 because no widths of 0 asm mov dx,SC_INDEX+1 asm out dx,al // set bit mask register asm lds si,DWORD PTR [postsource] asm call DWORD PTR [bp] // scale the line of pixels asm mov al,BYTE PTR [ss:mapmasks2-1+bx] // -1 because no widths of 0 asm or al,al asm jz nomore // // draw a second byte for vertical strips that cross two bytes // asm inc di asm out dx,al // set bit mask register asm call DWORD PTR [bp] // scale the line of pixels asm mov al,BYTE PTR [ss:mapmasks3-1+bx] // -1 because no widths of 0 asm or al,al asm jz nomore // // draw a third byte for vertical strips that cross three bytes // asm inc di asm out dx,al // set bit mask register asm call DWORD PTR [bp] // scale the line of pixels nomore: asm mov ax,ss asm mov ds,ax } void FarScalePost (void) // just so other files can call { ScalePost (); } /* ==================== = = HitVertWall = = tilehit bit 7 is 0, because it's not a door tile = if bit 6 is 1 and the adjacent tile is a door tile, use door side pic = ==================== */ void HitVertWall (void) { s16int wallpic; u16int texture; texture = (yintercept>>4)&0xfc0; if (xtilestep == -1) { texture = 0xfc0-texture; xintercept += TILEGLOBAL; } wallheight[pixx] = CalcHeight(); if (lastside==1 && lastintercept == xtile && lasttilehit == tilehit) { // in the same wall type as last time, so check for optimized draw if (texture == (u16int)postsource) { // wide scale postwidth++; wallheight[pixx] = wallheight[pixx-1]; return; } else { ScalePost (); (u16int)postsource = texture; postwidth = 1; postx = pixx; } } else { // new wall if (lastside != -1) // if not the first scaled post ScalePost (); lastside = true; lastintercept = xtile; lasttilehit = tilehit; postx = pixx; postwidth = 1; if (tilehit & 0x40) { // check for adjacent doors ytile = yintercept>>TILESHIFT; if ( tilemap[xtile-xtilestep][ytile]&0x80 ) wallpic = DOORWALL+3; else wallpic = vertwall[tilehit & ~0x40]; } else wallpic = vertwall[tilehit]; *( ((u16int *)&postsource)+1) = (u16int)PM_GetPage(wallpic); (u16int)postsource = texture; } } /* ==================== = = HitHorizWall = = tilehit bit 7 is 0, because it's not a door tile = if bit 6 is 1 and the adjacent tile is a door tile, use door side pic = ==================== */ void HitHorizWall (void) { s16int wallpic; u16int texture; texture = (xintercept>>4)&0xfc0; if (ytilestep == -1) yintercept += TILEGLOBAL; else texture = 0xfc0-texture; wallheight[pixx] = CalcHeight(); if (lastside==0 && lastintercept == ytile && lasttilehit == tilehit) { // in the same wall type as last time, so check for optimized draw if (texture == (u16int)postsource) { // wide scale postwidth++; wallheight[pixx] = wallheight[pixx-1]; return; } else { ScalePost (); (u16int)postsource = texture; postwidth = 1; postx = pixx; } } else { // new wall if (lastside != -1) // if not the first scaled post ScalePost (); lastside = 0; lastintercept = ytile; lasttilehit = tilehit; postx = pixx; postwidth = 1; if (tilehit & 0x40) { // check for adjacent doors xtile = xintercept>>TILESHIFT; if ( tilemap[xtile][ytile-ytilestep]&0x80 ) wallpic = DOORWALL+2; else wallpic = horizwall[tilehit & ~0x40]; } else wallpic = horizwall[tilehit]; *( ((u16int *)&postsource)+1) = (u16int)PM_GetPage(wallpic); (u16int)postsource = texture; } } //========================================================================== /* ==================== = = HitHorizDoor = ==================== */ void HitHorizDoor (void) { u16int texture,doorpage,doornum; doornum = tilehit&0x7f; texture = ( (xintercept-doorposition[doornum]) >> 4) &0xfc0; wallheight[pixx] = CalcHeight(); if (lasttilehit == tilehit) { // in the same door as last time, so check for optimized draw if (texture == (u16int)postsource) { // wide scale postwidth++; wallheight[pixx] = wallheight[pixx-1]; return; } else { ScalePost (); (u16int)postsource = texture; postwidth = 1; postx = pixx; } } else { if (lastside != -1) // if not the first scaled post ScalePost (); // draw last post // first pixel in this door lastside = 2; lasttilehit = tilehit; postx = pixx; postwidth = 1; switch (doorobjlist[doornum].lock) { case dr_normal: doorpage = DOORWALL; break; case dr_lock1: case dr_lock2: case dr_lock3: case dr_lock4: doorpage = DOORWALL+6; break; case dr_elevator: doorpage = DOORWALL+4; break; } *( ((u16int *)&postsource)+1) = (u16int)PM_GetPage(doorpage); (u16int)postsource = texture; } } //========================================================================== /* ==================== = = HitVertDoor = ==================== */ void HitVertDoor (void) { u16int texture,doorpage,doornum; doornum = tilehit&0x7f; texture = ( (yintercept-doorposition[doornum]) >> 4) &0xfc0; wallheight[pixx] = CalcHeight(); if (lasttilehit == tilehit) { // in the same door as last time, so check for optimized draw if (texture == (u16int)postsource) { // wide scale postwidth++; wallheight[pixx] = wallheight[pixx-1]; return; } else { ScalePost (); (u16int)postsource = texture; postwidth = 1; postx = pixx; } } else { if (lastside != -1) // if not the first scaled post ScalePost (); // draw last post // first pixel in this door lastside = 2; lasttilehit = tilehit; postx = pixx; postwidth = 1; switch (doorobjlist[doornum].lock) { case dr_normal: doorpage = DOORWALL; break; case dr_lock1: case dr_lock2: case dr_lock3: case dr_lock4: doorpage = DOORWALL+6; break; case dr_elevator: doorpage = DOORWALL+4; break; } *( ((u16int *)&postsource)+1) = (u16int)PM_GetPage(doorpage+1); (u16int)postsource = texture; } } //========================================================================== /* ==================== = = HitHorizPWall = = A pushable wall in action has been hit = ==================== */ void HitHorizPWall (void) { s16int wallpic; u16int texture,offset; texture = (xintercept>>4)&0xfc0; offset = pwallpos<<10; if (ytilestep == -1) yintercept += TILEGLOBAL-offset; else { texture = 0xfc0-texture; yintercept += offset; } wallheight[pixx] = CalcHeight(); if (lasttilehit == tilehit) { // in the same wall type as last time, so check for optimized draw if (texture == (u16int)postsource) { // wide scale postwidth++; wallheight[pixx] = wallheight[pixx-1]; return; } else { ScalePost (); (u16int)postsource = texture; postwidth = 1; postx = pixx; } } else { // new wall if (lastside != -1) // if not the first scaled post ScalePost (); lasttilehit = tilehit; postx = pixx; postwidth = 1; wallpic = horizwall[tilehit&63]; *( ((u16int *)&postsource)+1) = (u16int)PM_GetPage(wallpic); (u16int)postsource = texture; } } /* ==================== = = HitVertPWall = = A pushable wall in action has been hit = ==================== */ void HitVertPWall (void) { s16int wallpic; u16int texture,offset; texture = (yintercept>>4)&0xfc0; offset = pwallpos<<10; if (xtilestep == -1) { xintercept += TILEGLOBAL-offset; texture = 0xfc0-texture; } else xintercept += offset; wallheight[pixx] = CalcHeight(); if (lasttilehit == tilehit) { // in the same wall type as last time, so check for optimized draw if (texture == (u16int)postsource) { // wide scale postwidth++; wallheight[pixx] = wallheight[pixx-1]; return; } else { ScalePost (); (u16int)postsource = texture; postwidth = 1; postx = pixx; } } else { // new wall if (lastside != -1) // if not the first scaled post ScalePost (); lasttilehit = tilehit; postx = pixx; postwidth = 1; wallpic = vertwall[tilehit&63]; *( ((u16int *)&postsource)+1) = (u16int)PM_GetPage(wallpic); (u16int)postsource = texture; } } //========================================================================== //========================================================================== #if 0 /* ===================== = = ClearScreen = ===================== */ void ClearScreen (void) { u16int floor=egaFloor[gamestate.episode*10+mapon], ceiling=egaCeiling[gamestate.episode*10+mapon]; // // clear the screen // asm mov dx,GC_INDEX asm mov ax,GC_MODE + 256*2 // read mode 0, write mode 2 asm out dx,ax asm mov ax,GC_BITMASK + 255*256 asm out dx,ax asm mov dx,40 asm mov ax,[viewwidth] asm shr ax,3 asm sub dx,ax // dx = 40-viewwidth/8 asm mov bx,[viewwidth] asm shr bx,4 // bl = viewwidth/16 asm mov bh,BYTE PTR [viewheight] asm shr bh,1 // half height asm mov ax,[ceiling] asm mov es,[screenseg] asm mov di,[bufferofs] toploop: asm mov cl,bl asm rep stosw asm add di,dx asm dec bh asm jnz toploop asm mov bh,BYTE PTR [viewheight] asm shr bh,1 // half height asm mov ax,[floor] bottomloop: asm mov cl,bl asm rep stosw asm add di,dx asm dec bh asm jnz bottomloop asm mov dx,GC_INDEX asm mov ax,GC_MODE + 256*10 // read mode 1, write mode 2 asm out dx,ax asm mov al,GC_BITMASK asm out dx,al } #endif //========================================================================== u16int vgaCeiling[]= { #ifndef SPEAR 0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x1d1d,0xbfbf, 0x4e4e,0x4e4e,0x4e4e,0x1d1d,0x8d8d,0x4e4e,0x1d1d,0x2d2d,0x1d1d,0x8d8d, 0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x1d1d,0x2d2d,0xdddd,0x1d1d,0x1d1d,0x9898, 0x1d1d,0x9d9d,0x2d2d,0xdddd,0xdddd,0x9d9d,0x2d2d,0x4d4d,0x1d1d,0xdddd, 0x7d7d,0x1d1d,0x2d2d,0x2d2d,0xdddd,0xd7d7,0x1d1d,0x1d1d,0x1d1d,0x2d2d, 0x1d1d,0x1d1d,0x1d1d,0x1d1d,0xdddd,0xdddd,0x7d7d,0xdddd,0xdddd,0xdddd #else 0x6f6f,0x4f4f,0x1d1d,0xdede,0xdfdf,0x2e2e,0x7f7f,0x9e9e,0xaeae,0x7f7f, 0x1d1d,0xdede,0xdfdf,0xdede,0xdfdf,0xdede,0xe1e1,0xdcdc,0x2e2e,0x1d1d,0xdcdc #endif }; /* ===================== = = VGAClearScreen = ===================== */ void VGAClearScreen (void) { u16int ceiling=vgaCeiling[gamestate.episode*10+mapon]; // // clear the screen // asm mov dx,SC_INDEX asm mov ax,SC_MAPMASK+15*256 // write through all planes asm out dx,ax asm mov dx,80 asm mov ax,[viewwidth] asm shr ax,2 asm sub dx,ax // dx = 40-viewwidth/2 asm mov bx,[viewwidth] asm shr bx,3 // bl = viewwidth/8 asm mov bh,BYTE PTR [viewheight] asm shr bh,1 // half height asm mov es,[screenseg] asm mov di,[bufferofs] asm mov ax,[ceiling] toploop: asm mov cl,bl asm rep stosw asm add di,dx asm dec bh asm jnz toploop asm mov bh,BYTE PTR [viewheight] asm shr bh,1 // half height asm mov ax,0x1919 bottomloop: asm mov cl,bl asm rep stosw asm add di,dx asm dec bh asm jnz bottomloop } //========================================================================== /* ===================== = = CalcRotate = ===================== */ s16int CalcRotate (objtype *ob) { s16int angle,viewangle; // this isn't exactly correct, as it should vary by a trig value, // but it is close enough with only eight rotations viewangle = player->angle + (centerx - ob->viewx)/8; if (ob->obclass == rocketobj || ob->obclass == hrocketobj) angle = (viewangle-180)- ob->angle; else angle = (viewangle-180)- dirangle[ob->dir]; angle+=ANGLES/16; while (angle>=ANGLES) angle-=ANGLES; while (angle<0) angle+=ANGLES; if (ob->state->rotate == 2) // 2 rotation pain frame return 4*(angle/(ANGLES/2)); // seperated by 3 (art layout...) return angle/(ANGLES/8); } /* ===================== = = DrawScaleds = = Draws all objects that are visable = ===================== */ #define MAXVISABLE 50 typedef struct { s16int viewx, viewheight, shapenum; } visobj_t; visobj_t vislist[MAXVISABLE],*visptr,*visstep,*farthest; void DrawScaleds (void) { s16int i,j,least,numvisable,height; uchar *shape; u8int *tilespot,*visspot; s16int shapenum; u16int spotloc; statobj_t *statptr; objtype *obj; visptr = &vislist[0]; // // place static objects // for (statptr = &statobjlist[0] ; statptr !=laststatobj ; statptr++) { if ((visptr->shapenum = statptr->shapenum) == -1) continue; // object has been deleted if (!*statptr->visspot) continue; // not visable if (TransformTile (statptr->tilex,statptr->tiley ,&visptr->viewx,&visptr->viewheight) && statptr->flags & FL_BONUS) { GetBonus (statptr); continue; } if (!visptr->viewheight) continue; // to close to the object if (visptr < &vislist[MAXVISABLE-1]) // don't let it overflow visptr++; } // // place active objects // for (obj = player->next;obj;obj=obj->next) { if (!(visptr->shapenum = obj->state->shapenum)) continue; // no shape spotloc = (obj->tilex<<6)+obj->tiley; // optimize: keep in struct? visspot = &spotvis[0][0]+spotloc; tilespot = &tilemap[0][0]+spotloc; // // could be in any of the nine surrounding tiles // if (*visspot || ( *(visspot-1) && !*(tilespot-1) ) || ( *(visspot+1) && !*(tilespot+1) ) || ( *(visspot-65) && !*(tilespot-65) ) || ( *(visspot-64) && !*(tilespot-64) ) || ( *(visspot-63) && !*(tilespot-63) ) || ( *(visspot+65) && !*(tilespot+65) ) || ( *(visspot+64) && !*(tilespot+64) ) || ( *(visspot+63) && !*(tilespot+63) ) ) { obj->active = true; TransformActor (obj); if (!obj->viewheight) continue; // too close or far away visptr->viewx = obj->viewx; visptr->viewheight = obj->viewheight; if (visptr->shapenum == -1) visptr->shapenum = obj->temp1; // special shape if (obj->state->rotate) visptr->shapenum += CalcRotate (obj); if (visptr < &vislist[MAXVISABLE-1]) // don't let it overflow visptr++; obj->flags |= FL_VISABLE; } else obj->flags &= ~FL_VISABLE; } // // draw from back to front // numvisable = visptr-&vislist[0]; if (!numvisable) return; // no visable objects for (i = 0; i<numvisable; i++) { least = 32000; for (visstep=&vislist[0] ; visstep<visptr ; visstep++) { height = visstep->viewheight; if (height < least) { least = height; farthest = visstep; } } // // draw farthest // ScaleShape(farthest->viewx,farthest->shapenum,farthest->viewheight); farthest->viewheight = 32000; } } //========================================================================== /* ============== = = DrawPlayerWeapon = = Draw the player's hands = ============== */ s16int weaponscale[NUMWEAPONS] = {SPR_KNIFEREADY,SPR_PISTOLREADY ,SPR_MACHINEGUNREADY,SPR_CHAINREADY}; void DrawPlayerWeapon (void) { s16int shapenum; #ifndef SPEAR if (gamestate.victoryflag) { if (player->state == &s_deathcam && (TimeCount&32) ) SimpleScaleShape(viewwidth/2,SPR_DEATHCAM,viewheight+1); return; } #endif if (gamestate.weapon != -1) { shapenum = weaponscale[gamestate.weapon]+gamestate.weaponframe; SimpleScaleShape(viewwidth/2,shapenum,viewheight+1); } if (demorecord || demoplayback) SimpleScaleShape(viewwidth/2,SPR_DEMO,viewheight+1); } //========================================================================== /* ===================== = = CalcTics = ===================== */ void CalcTics (void) { s32int newtime,oldtimecount; // // calculate tics since last refresh for adaptive timing // if (lasttimecount > TimeCount) TimeCount = lasttimecount; // if the game was paused a LONG time do { newtime = TimeCount; tics = newtime-lasttimecount; } while (!tics); // make sure at least one tic passes lasttimecount = newtime; if (tics>MAXTICS) { TimeCount -= (tics-MAXTICS); tics = MAXTICS; } } //========================================================================== /* ======================== = = FixOfs = ======================== */ void FixOfs (void) { VW_ScreenToScreen (displayofs,bufferofs,viewwidth/8,viewheight); } //========================================================================== /* ==================== = = WallRefresh = ==================== */ void WallRefresh (void) { // // set up variables for this view // viewangle = player->angle; midangle = viewangle*(FINEANGLES/ANGLES); viewsin = sintable[viewangle]; viewcos = costable[viewangle]; viewx = player->x - FixedByFrac(focallength,viewcos); viewy = player->y + FixedByFrac(focallength,viewsin); focaltx = viewx>>TILESHIFT; focalty = viewy>>TILESHIFT; viewtx = player->x >> TILESHIFT; viewty = player->y >> TILESHIFT; xpartialdown = viewx&(TILEGLOBAL-1); xpartialup = TILEGLOBAL-xpartialdown; ypartialdown = viewy&(TILEGLOBAL-1); ypartialup = TILEGLOBAL-ypartialdown; lastside = -1; // the first pixel is on a new wall AsmRefresh (); ScalePost (); // no more optimization on last post } //========================================================================== /* ======================== = = ThreeDRefresh = ======================== */ void ThreeDRefresh (void) { s16int tracedir; // this wouldn't need to be done except for my debugger/video wierdness outportb (SC_INDEX,SC_MAPMASK); // // clear out the traced array // asm mov ax,ds asm mov es,ax asm mov di,OFFSET spotvis asm xor ax,ax asm mov cx,2048 // 64*64 / 2 asm rep stosw bufferofs += screenofs; // // follow the walls from there to the right, drawwing as we go // VGAClearScreen (); WallRefresh (); // // draw all the scaled images // DrawScaleds(); // draw scaled stuff DrawPlayerWeapon (); // draw player's hands // // show screen and time last cycle // if (fizzlein) { FizzleFade(bufferofs,displayofs+screenofs,viewwidth,viewheight,20,false); fizzlein = false; lasttimecount = TimeCount = 0; // don't make a big tic count } bufferofs -= screenofs; displayofs = bufferofs; asm cli asm mov cx,[displayofs] asm mov dx,3d4h // CRTC address register asm mov al,0ch // start address high register asm out dx,al asm inc dx asm mov al,ch asm out dx,al // set the high byte asm sti bufferofs += SCREENSIZE; if (bufferofs > PAGE3START) bufferofs = PAGE1START; frameon++; PM_NextFrame(); } //===========================================================================