Add some comments from Fabien Sanglard article

src/client/refresh/soft/sw_bsp.c

@@ -24,7 +24,6 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 //
 // current entity info
 //
-qboolean	insubmodel;
 entity_t	*currententity;
 vec3_t		modelorg;	// modelorg is the viewpoint reletive to
 				// the currently rendering entity
@@ -643,5 +642,5 @@ void R_RenderWorld (void)
 	currentmodel = r_worldmodel;
 	r_pcurrentvertbase = currentmodel->vertexes;
 
-	R_RecursiveWorldNode (currentmodel->nodes, 15);
+	R_RecursiveWorldNode (currentmodel->nodes, ALIAS_XY_CLIP_MASK);
 }

src/client/refresh/soft/sw_draw.c

@@ -93,7 +93,6 @@ void RE_Draw_CharScaled(int x, int y, int num, float scale)
 	if (y <= -8)
 		return;	// totally off screen
 
-	//	if ( ( y + 8 ) >= vid.height )
 	if ( ( y + 8 ) > vid.height )	// PGM - status text was missing in sw...
 		return;
 

src/client/refresh/soft/sw_edge.c

@@ -659,15 +659,18 @@ void R_ScanEdges (void)
 
 		if (newedges[iv])
 		{
+			// Update AET with GET event
 			R_InsertNewEdges (newedges[iv], edge_head.next);
 		}
 
+		// Generate spans
 		(*pdrawfunc) ();
 
 		// flush the span list if we can't be sure we have enough spans left for
 		// the next scan
 		if (span_p > max_span_p)
 		{
+			// Draw stuff on screen
 			D_DrawSurfaces ();
 
 			// clear the surface span pointers
@@ -691,9 +694,12 @@ void R_ScanEdges (void)
 	// mark that the head (background start) span is pre-included
 	surfaces[1].spanstate = 1;
 
+	// Flush span buffer
 	if (newedges[iv])
+		// Update AET with GET event
 		R_InsertNewEdges (newedges[iv], edge_head.next);
 
+	// Update AET with GET event
 	(*pdrawfunc) ();
 
 	// draw whatever's left in the span list

src/client/refresh/soft/sw_image.c

@@ -104,8 +104,8 @@ R_LoadPic
 static image_t*
 R_LoadPic (char *name, byte *pic, int width, int height, imagetype_t type)
 {
-	image_t *image;
-	int i, c;
+	image_t	*image;
+	size_t	i, size;
 
 	image = R_FindFreeImage ();
 	if (strlen(name) >= sizeof(image->name))
@@ -117,10 +117,10 @@ R_LoadPic (char *name, byte *pic, int width, int height, imagetype_t type)
 	image->height = height;
 	image->type = type;
 
-	c = width*height;
-	image->pixels[0] = malloc (c);
+	size = width*height;
+	image->pixels[0] = malloc (size);
 	image->transparent = false;
-	for (i=0 ; i<c ; i++)
+	for (i=0 ; i<size ; i++)
 	{
 		if (pic[i] == 255)
 		{
@@ -129,8 +129,7 @@ R_LoadPic (char *name, byte *pic, int width, int height, imagetype_t type)
 		}
 	}
 
-	memcpy(image->pixels[0], pic, c);
-
+	memcpy(image->pixels[0], pic, size);
 	return image;
 }
 
@@ -240,7 +239,7 @@ image_t	*R_FindImage (char *name, imagetype_t type)
 
 	// fix backslashes
 	while ((ptr=strchr(name,'\\'))) {
-	  *ptr = '/';
+		*ptr = '/';
 	}
 #endif
 

src/client/refresh/soft/sw_main.c

@@ -186,6 +186,8 @@ pixel_t		*d_viewbuffer;
 zvalue_t	*d_pzbuffer;
 unsigned int	d_zwidth;
 
+qboolean	insubmodel;
+
 static struct texture_buffer {
 	image_t	image;
 	byte	buffer[1024];
@@ -311,7 +313,7 @@ static void
 R_UnRegister (void)
 {
 	ri.Cmd_RemoveCommand( "screenshot" );
-	ri.Cmd_RemoveCommand ("modellist");
+	ri.Cmd_RemoveCommand( "modellist" );
 	ri.Cmd_RemoveCommand( "imagelist" );
 }
 
@@ -783,7 +785,7 @@ R_DrawBEntitiesOnList
 static void
 R_DrawBEntitiesOnList (void)
 {
-	int			i, clipflags;
+	int		i, clipflags;
 	vec3_t		oldorigin;
 	vec3_t		mins, maxs;
 	float		minmaxs[6];
@@ -866,6 +868,8 @@ static surf_t	*lsurfs;
 /*
 ================
 R_EdgeDrawing
+
+Render the map
 ================
 */
 static void
@@ -892,6 +896,7 @@ R_EdgeDrawing (void)
 		surfaces--;
 	}
 
+	// Set function pointer pdrawfunc used later in this function
 	R_BeginEdgeFrame ();
 
 	if (r_dspeeds->value)
@@ -899,6 +904,8 @@ R_EdgeDrawing (void)
 		rw_time1 = SDL_GetTicks();
 	}
 
+	// Build the Global Edget Table
+	// Also populate the surface stack and count # surfaces to render (surf_max is the max)
 	R_RenderWorld ();
 
 	if (r_dspeeds->value)
@@ -915,6 +922,8 @@ R_EdgeDrawing (void)
 		se_time1 = db_time2;
 	}
 
+	// Use the Global Edge Table to maintin the Active Edge Table: Draw the world as scanlines
+	// Write the Z-Buffer (but no read)
 	R_ScanEdges ();
 }
 
@@ -1018,10 +1027,15 @@ RE_RenderFrame (refdef_t *fd)
 
 	R_SetupFrame ();
 
+	// Using the current view cluster (r_viewcluster), retrieve and decompress
+	// the PVS (Potentially Visible Set)
 	R_MarkLeaves ();	// done here so we know if we're in water
 
+	// For each dlight_t* passed via r_newrefdef.dlights, mark polygons affected by a light.
 	R_PushDlights (r_worldmodel);
 
+	// Build the Global Edge Table and render it via the Active Edge Table
+	// Render the map
 	R_EdgeDrawing ();
 
 	if (r_dspeeds->value)
@@ -1030,6 +1044,8 @@ RE_RenderFrame (refdef_t *fd)
 		de_time1 = se_time2;
 	}
 
+	// Draw enemies, barrel etc...
+	// Use Z-Buffer in read mode only.
 	R_DrawEntitiesOnList ();
 
 	if (r_dspeeds->value)
@@ -1038,13 +1054,16 @@ RE_RenderFrame (refdef_t *fd)
 		dp_time1 = SDL_GetTicks();
 	}
 
+	// Duh !
 	R_DrawParticles ();
 
 	if (r_dspeeds->value)
 		dp_time2 = SDL_GetTicks();
 
+	// Perform pixel palette blending ia the pics/colormap.pcx lower part lookup table.
 	R_DrawAlphaSurfaces();
 
+	// Save off light value for server to look at (BIG HACK!)
 	R_SetLightLevel ();
 
 	if (r_dowarp)
@@ -1056,6 +1075,7 @@ RE_RenderFrame (refdef_t *fd)
 	if (r_dspeeds->value)
 		da_time2 = SDL_GetTicks();
 
+	// Modify the palette (when taking hit or pickup item) so all colors are modified
 	R_CalcPalette ();
 
 	if (sw_aliasstats->value)
@@ -1314,11 +1334,11 @@ R_DrawBeam( entity_t *e )
 	for ( i = 0; i < NUM_BEAM_SEGS; i++ )
 	{
 		R_IMFlatShadedQuad( start_points[i],
-		                    end_points[i],
-							end_points[(i+1)%NUM_BEAM_SEGS],
-							start_points[(i+1)%NUM_BEAM_SEGS],
-							e->skinnum & 0xFF,
-							e->alpha );
+				    end_points[i],
+				    end_points[(i+1)%NUM_BEAM_SEGS],
+				    start_points[(i+1)%NUM_BEAM_SEGS],
+				    e->skinnum & 0xFF,
+				    e->alpha );
 	}
 }
 

src/client/refresh/soft/sw_model.c

@@ -192,13 +192,11 @@ mleaf_t *Mod_PointInLeaf (vec3_t p, model_t *model)
 		ri.Sys_Error (ERR_DROP, "Mod_PointInLeaf: bad model");
 
 	node = model->nodes;
-	while (1)
+	while (node->contents == -1)
 	{
 		float d;
 		mplane_t *plane;
 
-		if (node->contents != -1)
-			return (mleaf_t *)node;
 		plane = node->plane;
 		d = DotProduct (p,plane->normal) - plane->dist;
 		if (d > 0)
@@ -207,7 +205,7 @@ mleaf_t *Mod_PointInLeaf (vec3_t p, model_t *model)
 			node = node->children[1];
 	}
 
-	return NULL;	// never reached
+	return (mleaf_t *)node;
 }
 
 

src/client/refresh/soft/sw_scan.c

@@ -65,7 +65,7 @@ void D_WarpScreen (void)
 			int v2;
 
 			v2 = (int)((float)v/(h + AMP2 * 2) * r_refdef.vrect.height);
-			warp_rowptr[v] = r_warpbuffer + (r_refdef.vrect.width * v2);
+			warp_rowptr[v] = r_warpbuffer + (vid.width * v2);
 		}
 
 		for (u=0 ; u<w+AMP2*2 ; u++)