Merge branch 'clip-sprites-optimize' into 'master'

Drawseg clipping optimized, from prboom-plus

See merge request KartKrew/Kart-Public!304

src/r_things.c

@@ -80,6 +80,33 @@ static spriteframe_t sprtemp[64];
 static size_t maxframe;
 static const char *spritename;
 
+//
+// Clipping against drawsegs optimization, from prboom-plus
+//
+// TODO: This should be done with proper subsector pass through
+// sprites which would ideally remove the need to do it at all.
+// Unfortunately, SRB2's drawing loop has lots of annoying
+// changes from Doom for portals, which make it hard to implement.
+
+typedef struct drawseg_xrange_item_s
+{
+	INT16 x1, x2;
+	drawseg_t *user;
+} drawseg_xrange_item_t;
+
+typedef struct drawsegs_xrange_s
+{
+	drawseg_xrange_item_t *items;
+	INT32 count;
+} drawsegs_xrange_t;
+
+#define DS_RANGES_COUNT 3
+static drawsegs_xrange_t drawsegs_xranges[DS_RANGES_COUNT];
+
+static drawseg_xrange_item_t *drawsegs_xrange;
+static size_t drawsegs_xrange_size = 0;
+static INT32 drawsegs_xrange_count = 0;
+
 // ==========================================================================
 //
 // Sprite loading routines: support sprites in pwad, dehacked sprite renaming,
@@ -548,7 +575,7 @@ void R_DelSpriteDefs(UINT16 wadnum)
 //
 // GAME FUNCTIONS
 //
-static UINT32 visspritecount;
+UINT32 visspritecount;
 static UINT32 clippedvissprites;
 static vissprite_t *visspritechunks[MAXVISSPRITES >> VISSPRITECHUNKBITS] = {NULL};
 
@@ -2274,10 +2301,7 @@ static void R_DrawPrecipitationSprite(vissprite_t *spr)
 
 // R_ClipSprites
 // Clips vissprites without drawing, so that portals can work. -Red
-void R_ClipSprites(void)
-{
-	vissprite_t *spr;
-	for (;clippedvissprites < visspritecount; clippedvissprites++)
+void R_ClipVisSprite(vissprite_t *spr, INT32 x1, INT32 x2)
 {
 	drawseg_t *ds;
 	INT32		x;
@@ -2287,10 +2311,10 @@ void R_ClipSprites(void)
 	fixed_t		lowscale;
 	INT32		silhouette;
 
-		spr = R_GetVisSprite(clippedvissprites);
-
-		for (x = spr->x1; x <= spr->x2; x++)
+	for (x = x1; x <= x2; x++)
+	{
 		spr->clipbot[x] = spr->cliptop[x] = -2;
+	}
 
 	// Scan drawsegs from end to start for obscuring segs.
 	// The first drawseg that has a greater scale
@@ -2299,19 +2323,23 @@ void R_ClipSprites(void)
 	// Pointer check was originally nonportable
 	// and buggy, by going past LEFT end of array:
 
-		//    for (ds = ds_p-1; ds >= drawsegs; ds--)    old buggy code
-		for (ds = ds_p; ds-- > drawsegs ;)
+	// e6y: optimization
+	if (drawsegs_xrange_size)
+	{
+		const drawseg_xrange_item_t *last = &drawsegs_xrange[drawsegs_xrange_count - 1];
+		drawseg_xrange_item_t *curr = &drawsegs_xrange[-1];
+
+		while (++curr <= last)
 		{
 			// determine if the drawseg obscures the sprite
-			if (ds->x1 > spr->x2 ||
-			    ds->x2 < spr->x1 ||
-			    (!ds->silhouette
-			     && !ds->maskedtexturecol))
+			if (curr->x1 > spr->x2 || curr->x2 < spr->x1)
 			{
 				// does not cover sprite
 				continue;
 			}
 
+			ds = curr->user;
+
 			if (ds->portalpass > 0 && ds->portalpass <= portalrender)
 				continue; // is a portal
 
@@ -2375,6 +2403,7 @@ void R_ClipSprites(void)
 				}
 			}
 		}
+	}
 	//SoM: 3/17/2000: Clip sprites in water.
 	if (spr->heightsec != -1)  // only things in specially marked sectors
 	{
@@ -2457,6 +2486,91 @@ void R_ClipSprites(void)
 			spr->cliptop[x] = (INT16)con_clipviewtop;
 	}
 }
+
+void R_ClipSprites(void)
+{
+	const size_t maxdrawsegs = ds_p - drawsegs;
+	const INT32 cx = viewwidth / 2;
+	drawseg_t* ds;
+	INT32 i;
+
+	// e6y
+	// Reducing of cache misses in the following R_DrawSprite()
+	// Makes sense for scenes with huge amount of drawsegs.
+	// ~12% of speed improvement on epic.wad map05
+	for (i = 0; i < DS_RANGES_COUNT; i++)
+	{
+		drawsegs_xranges[i].count = 0;
+	}
+
+	if (visspritecount - clippedvissprites <= 0)
+	{
+		return;
+	}
+
+	if (drawsegs_xrange_size < maxdrawsegs)
+	{
+		drawsegs_xrange_size = 2 * maxdrawsegs;
+
+		for (i = 0; i < DS_RANGES_COUNT; i++)
+		{
+			drawsegs_xranges[i].items = Z_Realloc(
+				drawsegs_xranges[i].items,
+				drawsegs_xrange_size * sizeof(drawsegs_xranges[i].items[0]),
+				PU_STATIC, NULL
+			);
+		}
+	}
+
+	for (ds = ds_p; ds-- > drawsegs;)
+	{
+		if (ds->silhouette || ds->maskedtexturecol)
+		{
+			drawsegs_xranges[0].items[drawsegs_xranges[0].count].x1 = ds->x1;
+			drawsegs_xranges[0].items[drawsegs_xranges[0].count].x2 = ds->x2;
+			drawsegs_xranges[0].items[drawsegs_xranges[0].count].user = ds;
+
+			// e6y: ~13% of speed improvement on sunder.wad map10
+			if (ds->x1 < cx)
+			{
+				drawsegs_xranges[1].items[drawsegs_xranges[1].count] = 
+					drawsegs_xranges[0].items[drawsegs_xranges[0].count];
+				drawsegs_xranges[1].count++;
+			}
+
+			if (ds->x2 >= cx)
+			{
+				drawsegs_xranges[2].items[drawsegs_xranges[2].count] = 
+					drawsegs_xranges[0].items[drawsegs_xranges[0].count];
+				drawsegs_xranges[2].count++;
+			}
+
+			drawsegs_xranges[0].count++;
+		}
+	}
+
+	for (; clippedvissprites < visspritecount; clippedvissprites++)
+	{
+		vissprite_t *spr = R_GetVisSprite(clippedvissprites);
+
+		if (spr->x2 < cx)
+		{
+			drawsegs_xrange = drawsegs_xranges[1].items;
+			drawsegs_xrange_count = drawsegs_xranges[1].count;
+		}
+		else if (spr->x1 >= cx)
+		{
+			drawsegs_xrange = drawsegs_xranges[2].items;
+			drawsegs_xrange_count = drawsegs_xranges[2].count;
+		}
+		else
+		{
+			drawsegs_xrange = drawsegs_xranges[0].items;
+			drawsegs_xrange_count = drawsegs_xranges[0].count;
+		}
+
+		R_ClipVisSprite(spr, spr->x1, spr->x2);
+	}
 }
 
 //

src/r_things.h

@@ -58,7 +58,6 @@ void R_DelSpriteDefs(UINT16 wadnum);
 void R_AddSprites(sector_t *sec, INT32 lightlevel);
 void R_InitSprites(void);
 void R_ClearSprites(void);
-void R_ClipSprites(void);
 void R_DrawMasked(void);
 
 // -----------
@@ -163,6 +162,17 @@ typedef struct vissprite_s
 	fixed_t thingscale;
 } vissprite_t;
 
+extern UINT32 visspritecount;
+
+void R_ClipSprites(void);
+void R_ClipVisSprite(vissprite_t *spr, INT32 x1, INT32 x2);
+
+UINT8 *R_GetSpriteTranslation(vissprite_t *vis);
+
+// ----------
+// DRAW NODES
+// ----------
+
 // A drawnode is something that points to a 3D floor, 3D side, or masked
 // middle texture. This is used for sorting with sprites.
 typedef struct drawnode_s