wl_draw.c, wl_main.c: cleanups

wl_main.c: fixed hard to find raycasting bug in BuildTables where in certain
circumstances a casted ray would miss the wall it should have hit.

src/vi_svga.c

@@ -32,9 +32,8 @@ void Quit(char *error)
 	ShutdownId();
 	
 	if (screen) {
-		printf("TODO: spiffy ansi screen goes here..\n");
 		/* doesn't look too good on console at the moment ...*/
-		//DisplayTextSplash(screen);
+		/* DisplayTextSplash(screen); */
 	}
 	
 	if (error && *error) {

src/wl_draw.c

@@ -11,12 +11,8 @@
 static unsigned wallheight[MAXVIEWWIDTH];
 
 /* refresh variables */
-fixed viewx,viewy;		/* the focal point */
+fixed viewx, viewy;		/* the focal point */
 
-/* ray casting variables */
-static int focaltx, focalty;
-
-static unsigned xpartial, ypartial;
 static int viewangle;
 
 static unsigned tilehit;
@@ -24,7 +20,6 @@ static unsigned tilehit;
 static int xtile, ytile;
 static int xtilestep, ytilestep;
 static long xintercept, yintercept;
-static long xstep, ystep;
 
 static unsigned postx;
 
@@ -219,16 +214,12 @@ static int CalcRotate(objtype *ob)
 =
 = DrawScaleds
 =
-= Draws all objects that are visable
+= Draws all objects that are visible
 =
 =====================
 */
 
-#ifdef DUMBTEST
-#define MAXVISABLE	640
-#else
 #define MAXVISABLE      64
-#endif
 
 typedef struct {
 	int viewx;
@@ -249,16 +240,14 @@ static void DrawScaleds()
 
 	visptr = &vislist[0];
 
-//
-// place static objects
-//
+/* place static objects */
 	for (statptr = &statobjlist[0]; statptr != laststatobj; statptr++)
 	{
 		if ((visptr->shapenum = statptr->shapenum) == -1)
-			continue;						// object has been deleted
+			continue;			/* object has been deleted */
 
 		if (!*statptr->visspot)
-			continue;						// not visable
+			continue;			/* not visable */
 
 		if (TransformTile(statptr->tilex, statptr->tiley
 			,&visptr->viewx,&visptr->viewheight) && statptr->flags & FL_BONUS)
@@ -268,7 +257,7 @@ static void DrawScaleds()
 		}
 
 		if (!visptr->viewheight)
-			continue;						// to close to the object
+			continue;			/* too close to the object */
 
 		if (visptr < &vislist[MAXVISABLE-1])	/* don't let it overflow */
 			visptr++;
@@ -397,18 +386,12 @@ static void DrawPlayerWeapon()
 
 static void WallRefresh()
 {
-/*
- set up variables for this view
-*/
 	viewangle = player->angle;
 	
 	viewsin = sintable[viewangle];
 	viewcos = costable[viewangle];
-	viewx = player->x - FixedByFrac(focallength,viewcos);
-	viewy = player->y + FixedByFrac(focallength,viewsin);
-
-	focaltx = viewx>>TILESHIFT;
-	focalty = viewy>>TILESHIFT;
+	viewx = player->x - FixedByFrac(focallength, viewcos);
+	viewy = player->y + FixedByFrac(focallength, viewsin);
 
 	AsmRefresh();
 }
@@ -450,10 +433,6 @@ static void MapRow()
 		//mr_yfrac += mr_ystep;
 		//mr_xfrac += mr_xstep;
 		
-	/*	
-		mr_dest[0] = planepics[0x1F00|(planepics[(ebx&0x1FFE)+0]&0xFF)];
-		mr_dest[mr_rowofs] = planepics[0x1F00|(planepics[(ebx&0x1FFE)+1]&0xFF)];
-	*/
 		mr_dest[0] = planepics[ebx+0];
 		mr_dest[mr_rowofs] = planepics[ebx+1];
 		mr_dest++;
@@ -633,9 +612,6 @@ void ThreeDRefresh()
 /* clear out the traced array */
 	memset(spotvis, 0, sizeof(spotvis));
 
-/* follow the walls from there to the right, drawing as we go */
-	
-	/* DrawPlayBorder(); */
 #ifndef DRAWCEIL	
 	ClearScreen();
 #endif	
@@ -734,15 +710,15 @@ static void ScaleLineTrans(unsigned int height, byte *source, int x)
 	}
 }
 
-static unsigned char *spritegfx[SPR_TOTAL];
+static byte *spritegfx[SPR_TOTAL];
 
 static void DeCompileSprite(int shapenum)
 {
-	unsigned char *ptr;
-	unsigned char *buf;
-	unsigned char *cmdptr;
-	unsigned char *pixels;
-	short int yoff; /* int16_t */
+	byte *ptr;
+	byte *buf;
+	byte *cmdptr;
+	byte *pixels;
+	int yoff;
 	int y, y0, y1;
 	int x, left, right;
 	int cmd;
@@ -768,7 +744,7 @@ static void DeCompileSprite(int shapenum)
 		while (ptr[cmd+0]) {
 			/* y1 = (ptr[cmd+0] | (ptr[cmd+1] << 8)) / 2; */
 			y1 = ptr[cmd+0] / 2;
-			yoff = ptr[cmd+2] | (ptr[cmd+3] << 8);
+			yoff = (int16_t)(ptr[cmd+2] | (ptr[cmd+3] << 8));
 			/* y0 = (ptr[cmd+4] | (ptr[cmd+5] << 8)) / 2; */
 			y0 = ptr[cmd+4] / 2;
 			
@@ -1058,15 +1034,17 @@ static int samey(int intercept, int tile)
 		else
 			return 1;
 	}
- }
+}
 
 static void AsmRefresh()
 {
-	fixed doorxhit, dooryhit;
-	long xtemp, ytemp;
 	unsigned xpartialup, xpartialdown, ypartialup, ypartialdown;
+	unsigned xpartial, ypartial;
+	int doorhit;
 	int angle;    /* ray angle through postx */
 	int midangle;
+	int focaltx, focalty;
+	int xstep, ystep;
 	
 	midangle = viewangle*(FINEANGLES/ANGLES);
 	xpartialdown = viewx&(TILEGLOBAL-1);
@@ -1074,6 +1052,9 @@ static void AsmRefresh()
 	ypartialdown = viewy&(TILEGLOBAL-1);
 	ypartialup = TILEGLOBAL-ypartialdown;
 
+	focaltx = viewx>>TILESHIFT;
+	focalty = viewy>>TILESHIFT;
+
 for (postx = 0; postx < viewwidth; postx++) {
 	angle = midangle + pixelangle[postx];
 
@@ -1120,6 +1101,7 @@ for (postx = 0; postx < viewwidth; postx++) {
 		goto entry90;
 	}
 	
+	
 	yintercept = viewy + xpartialbyystep();
 	xtile = focaltx + xtilestep;
 
@@ -1128,40 +1110,40 @@ for (postx = 0; postx < viewwidth; postx++) {
 
 /* CORE LOOP */
 
-#define TILE(n) (n>>16)
+#define TILE(n) ((n)>>16)
 
 	/* check intersections with vertical walls */
-vertcheck:
+ vertcheck:
 	if (!samey(yintercept, ytile))
 		goto horizentry;
 		
 vertentry:
 	tilehit = tilemap[xtile][TILE(yintercept)];
 
-	if (tilehit != 0) {
+	if (tilehit) {
 		if (tilehit & 0x80) {
 			if (tilehit & 0x40) {
 				/* vertpushwall */
-				ytemp = yintercept + (signed)((signed)pwallpos * ystep) / 64;
+				doorhit = yintercept + (signed)((signed)pwallpos * ystep) / 64;
 			
-				if (TILE(ytemp) != TILE(yintercept)) 
+				if (TILE(doorhit) != TILE(yintercept)) 
 					goto passvert;
 					
-				yintercept = ytemp;
+				yintercept = doorhit;
 				xintercept = xtile << 16;
 				HitVertPWall();
 			} else {
 				/* vertdoor */
-				dooryhit = yintercept + ystep / 2;
+				doorhit = yintercept + ystep / 2;
 
-				if (TILE(dooryhit) != TILE(yintercept))
+				if (TILE(doorhit) != TILE(yintercept))
 					goto passvert;
 				
 				/* check door position */
-				if ((dooryhit&0xFFFF) < doorposition[tilehit&0x7f])
+				if ((doorhit&0xFFFF) < doorposition[tilehit&0x7f])
 					goto passvert;
 				
-				yintercept = dooryhit;
+				yintercept = doorhit;
 				xintercept = (xtile << 16) + 32768;
 				HitVertDoor();
 			}
@@ -1186,29 +1168,29 @@ horizcheck:
 horizentry:
 	tilehit = tilemap[TILE(xintercept)][ytile];
 
-	if (tilehit != 0) {
+	if (tilehit) {
 		if (tilehit & 0x80) {
 			if (tilehit & 0x40) {
-				xtemp = xintercept + (signed)((signed)pwallpos * xstep) / 64;
+				doorhit = xintercept + (signed)((signed)pwallpos * xstep) / 64;
 		    	
 				/* horizpushwall */
-				if (TILE(xtemp) != TILE(xintercept))
+				if (TILE(doorhit) != TILE(xintercept))
 					goto passhoriz;
 				
-				xintercept = xtemp;
+				xintercept = doorhit;
 				yintercept = ytile << 16; 
 				HitHorizPWall();
 			} else {
-				doorxhit = xintercept + xstep / 2;
+				doorhit = xintercept + xstep / 2;
 				
-				if (TILE(doorxhit) != TILE(xintercept))
+				if (TILE(doorhit) != TILE(xintercept))
 					goto passhoriz;
 				
 				/* check door position */
-				if ((doorxhit&0xFFFF) < doorposition[tilehit&0x7f])
+				if ((doorhit&0xFFFF) < doorposition[tilehit&0x7f])
 					goto passhoriz;
 				
-				xintercept = doorxhit;
+				xintercept = doorhit;
 				yintercept = (ytile << 16) + 32768;
 				HitHorizDoor();
 			}
@@ -1224,7 +1206,4 @@ passhoriz:
 	xintercept += xstep;
 	goto horizcheck;
 }
-#ifdef DUMBTEST
-	memset(spotvis, 1, sizeof(spotvis));
-#endif
 }

src/wl_main.c

@@ -881,53 +881,47 @@ void InitDigiMap()
 =
 = BuildTables
 =
-= Calculates:
-=
-= scale                 projection constant
-= sintable/costable     overlapping fractional tables
-=
 ==================
 */
 
-static const float radtoint = (float)FINEANGLES/2.0f/PI;
+static const double radtoint = (double)FINEANGLES/2.0/PI;
 
 void BuildTables()
 {
 	int i;
-  float         angle,anglestep;
-  double        tang;
+	double tang, angle, anglestep;
 	fixed value;
 
+/* calculate fine tangents */
 
-//
-// calculate fine tangents
-//
-
-	for (i=0;i<FINEANGLES/8;i++)
-	{
-		tang = tan((i+0.5)/radtoint);
+	for (i = 0; i < FINEANGLES/8; i++) {
+		tang = tan((double)i/radtoint);
 		finetangent[i] = tang*TILEGLOBAL;
 		finetangent[FINEANGLES/4-1-i] = 1/tang*TILEGLOBAL;
 	}
 	
+	/* fight off asymptotic behaviour at 90 degrees */
+	finetangent[FINEANGLES/4-1] = finetangent[FINEANGLES/4-2];
+	
 //
 // costable overlays sintable with a quarter phase shift
 // ANGLES is assumed to be divisable by four
 //
 
-  angle = 0;
-  anglestep = PI/2/ANGLEQUAD;
-  for (i=0;i<=ANGLEQUAD;i++)
-  {
-	value=GLOBAL1*sin(angle);
-	sintable[i]=
-	  sintable[i+ANGLES]=
+	angle = 0.0;
+	anglestep = PI/2.0/ANGLEQUAD;
+	for (i = 0; i <= ANGLEQUAD; i++) {
+		value = GLOBAL1*sin(angle);
+		
+		sintable[i] = 
+		sintable[i+ANGLES] =  
 		sintable[ANGLES/2-i] = value;
-	sintable[ANGLES-i]=
+		
+		sintable[ANGLES-i] =
 		sintable[ANGLES/2+i] = -value;
+		
 		angle += anglestep;
 	}
-
 }
 
 /*
@@ -942,10 +936,8 @@ void CalcProjection(long focal)
 {
 	int     i;
 	long    intang;
-	float   angle;
-	double  tang;
+	double angle, tang, facedist;
 	int     halfview;
-	double  facedist;
 
 	focallength = focal;
 	facedist = focal+MINDIST;
@@ -967,10 +959,8 @@ void CalcProjection(long focal)
 // calculate the angle offset from view angle of each pixel's ray
 //
 
-	for (i=0;i<halfview;i++)
-	{
-	// start 1/2 pixel over, so viewangle bisects two middle pixels
-		tang = (long)i*VIEWGLOBAL/viewwidth/facedist;
+	for (i = 0; i < halfview; i++) {
+		tang = ((double)i)*VIEWGLOBAL/viewwidth/facedist;
 		angle = atan(tang);
 		intang = angle*radtoint;
 		pixelangle[halfview-1-i] = intang;