r_main.c

制作游戏 魔法师传奇 源代码设计 MOFASHICHUANQI 经典老游戏

=
= R_InitTextureMapping
=
=================
*/

void R_InitTextureMapping (void)
{
	int			i;
	int			x;
	int			t;
	fixed_t		focallength;


//
// use tangent table to generate viewangletox
// viewangletox will give the next greatest x after the view angle
//
	// calc focallength so FIELDOFVIEW angles covers SCREENWIDTH
	focallength = FixedDiv (centerxfrac
	, finetangent[FINEANGLES/4+FIELDOFVIEW/2] );

	for (i=0 ; i<FINEANGLES/2 ; i++)
	{
		if (finetangent[i] > FRACUNIT*2)
			t = -1;
		else if (finetangent[i] < -FRACUNIT*2)
			t = viewwidth+1;
		else
		{
			t = FixedMul (finetangent[i], focallength);
			t = (centerxfrac - t+FRACUNIT-1)>>FRACBITS;
			if (t < -1)
				t = -1;
			else if (t>viewwidth+1)
				t = viewwidth+1;
		}
		viewangletox[i] = t;
	}

//
// scan viewangletox[] to generate xtoviewangleangle[]
//
// xtoviewangle will give the smallest view angle that maps to x
	for (x=0;x<=viewwidth;x++)
	{
		i = 0;
		while (viewangletox[i]>x)
			i++;
		xtoviewangle[x] = (i<<ANGLETOFINESHIFT)-ANG90;
	}

//
// take out the fencepost cases from viewangletox
//
	for (i=0 ; i<FINEANGLES/2 ; i++)
	{
		t = FixedMul (finetangent[i], focallength);
		t = centerx - t;
		if (viewangletox[i] == -1)
			viewangletox[i] = 0;
		else if (viewangletox[i] == viewwidth+1)
			viewangletox[i]  = viewwidth;
	}

	clipangle = xtoviewangle[0];
}

//=============================================================================

/*
====================
=
= R_InitLightTables
=
= Only inits the zlight table, because the scalelight table changes
= with view size
=
====================
*/

#define		DISTMAP	2

void R_InitLightTables (void)
{
	int		i,j, level, startmap;
	int		scale;

//
// Calculate the light levels to use for each level / distance combination
//
	for (i=0 ; i< LIGHTLEVELS ; i++)
	{
		startmap = ((LIGHTLEVELS-1-i)*2)*NUMCOLORMAPS/LIGHTLEVELS;
		for (j=0 ; j<MAXLIGHTZ ; j++)
		{
			scale = FixedDiv ((SCREENWIDTH/2*FRACUNIT), (j+1)<<LIGHTZSHIFT);
			scale >>= LIGHTSCALESHIFT;
			level = startmap - scale/DISTMAP;
			if (level < 0)
				level = 0;
			if (level >= NUMCOLORMAPS)
				level = NUMCOLORMAPS-1;
			zlight[i][j] = colormaps + level*256;
		}
	}
}


/*
==============
=
= R_SetViewSize
=
= Don't really change anything here, because i might be in the middle of
= a refresh.  The change will take effect next refresh.
=
==============
*/

boolean	setsizeneeded;
int		setblocks, setdetail;

void R_SetViewSize (int blocks, int detail)
{
	setsizeneeded = true;
	setblocks = blocks;
	setdetail = detail;
}

/*
==============
=
= R_ExecuteSetViewSize
=
==============
*/

void R_ExecuteSetViewSize (void)
{
	fixed_t	cosadj, dy;
	int		i,j, level, startmap;

	setsizeneeded = false;

	if (setblocks == 11)
	{
		scaledviewwidth = SCREENWIDTH;
		viewheight = SCREENHEIGHT;
	}
	else
	{
		scaledviewwidth = setblocks*32;
		viewheight = (setblocks*161/10);
	}

	detailshift = setdetail;
	viewwidth = scaledviewwidth>>detailshift;

	centery = viewheight/2;
	centerx = viewwidth/2;
	centerxfrac = centerx<<FRACBITS;
	centeryfrac = centery<<FRACBITS;
	projection = centerxfrac;

	if (!detailshift)
	{
		colfunc = basecolfunc = R_DrawColumn;
		fuzzcolfunc = R_DrawFuzzColumn;
		transcolfunc = R_DrawTranslatedColumn;
		spanfunc = R_DrawSpan;
	}
	else
	{
		colfunc = basecolfunc = R_DrawColumnLow;
		fuzzcolfunc = R_DrawFuzzColumn;
		transcolfunc = R_DrawTranslatedColumn;
		spanfunc = R_DrawSpanLow;
	}

	R_InitBuffer (scaledviewwidth, viewheight);

	R_InitTextureMapping ();

//
// psprite scales
//
	pspritescale = FRACUNIT*viewwidth/SCREENWIDTH;
	pspriteiscale = FRACUNIT*SCREENWIDTH/viewwidth;

//
// thing clipping
//
	for (i=0 ; i<viewwidth ; i++)
		screenheightarray[i] = viewheight;

//
// planes
//
	for (i=0 ; i<viewheight ; i++)
	{
		dy = ((i-viewheight/2)<<FRACBITS)+FRACUNIT/2;
		dy = abs(dy);
		yslope[i] = FixedDiv ( (viewwidth<<detailshift)/2*FRACUNIT, dy);
	}

	for (i=0 ; i<viewwidth ; i++)
	{
		cosadj = abs(finecosine[xtoviewangle[i]>>ANGLETOFINESHIFT]);
		distscale[i] = FixedDiv (FRACUNIT,cosadj);
	}

//
// Calculate the light levels to use for each level / scale combination
//
	for (i=0 ; i< LIGHTLEVELS ; i++)
	{
		startmap = ((LIGHTLEVELS-1-i)*2)*NUMCOLORMAPS/LIGHTLEVELS;
		for (j=0 ; j<MAXLIGHTSCALE ; j++)
		{
			level = startmap - j*SCREENWIDTH/(viewwidth<<detailshift)/DISTMAP;
			if (level < 0)
				level = 0;
			if (level >= NUMCOLORMAPS)
				level = NUMCOLORMAPS-1;
			scalelight[i][j] = colormaps + level*256;
		}
	}

//
// draw the border
//
	R_DrawViewBorder ();    // erase old menu stuff
}


/*
==============
=
= R_Init
=
==============
*/

int detailLevel;
int screenblocks;

void R_Init(void)
{
	R_InitData();
	R_InitPointToAngle();
	R_InitTables();
	// viewwidth / viewheight / detailLevel are set by the defaults
	R_SetViewSize(screenblocks, detailLevel);
	R_InitPlanes();
	R_InitLightTables();
	R_InitSkyMap();
	R_InitTranslationTables();
	framecount = 0;
}

/*
==============
=
= R_PointInSubsector
=
==============
*/

subsector_t *R_PointInSubsector (fixed_t x, fixed_t y)
{
	node_t	*node;
	int		side, nodenum;

	if (!numnodes)				// single subsector is a special case
		return subsectors;

	nodenum = numnodes-1;

	while (! (nodenum & NF_SUBSECTOR) )
	{
		node = &nodes[nodenum];
		side = R_PointOnSide (x, y, node);
		nodenum = node->children[side];
	}

	return &subsectors[nodenum & ~NF_SUBSECTOR];

}

//----------------------------------------------------------------------------
//
// PROC R_SetupFrame
//
//----------------------------------------------------------------------------

void R_SetupFrame(player_t *player)
{
	int i;
	int tableAngle;
	int tempCentery;
	int intensity;

	//drawbsp = 1;
	viewplayer = player;
#ifdef __WATCOMC__
	if(newViewAngleOff)
	{
		viewangleoffset = newViewAngleOff<<ANGLETOFINESHIFT;
	}
#endif
	viewangle = player->mo->angle+viewangleoffset;
	tableAngle = viewangle>>ANGLETOFINESHIFT;
	viewx = player->mo->x;
	viewy = player->mo->y;

	if(localQuakeHappening[displayplayer] && !paused)
	{
		intensity = localQuakeHappening[displayplayer];
		viewx += ((M_Random() % (intensity<<2))
					-(intensity<<1))<<FRACBITS;
		viewy += ((M_Random()%(intensity<<2))
					-(intensity<<1))<<FRACBITS;
	}

	extralight = player->extralight;
	viewz = player->viewz;
	
	tempCentery = viewheight/2+(player->lookdir)*screenblocks/10;
	if(centery != tempCentery)
	{
		centery = tempCentery;
		centeryfrac = centery<<FRACBITS;
		for(i = 0; i < viewheight; i++)
		{
			yslope[i] = FixedDiv ((viewwidth<<detailshift)/2*FRACUNIT,
				abs(((i-centery)<<FRACBITS)+FRACUNIT/2));
		}
	}
	viewsin = finesine[tableAngle];
	viewcos = finecosine[tableAngle];
	sscount = 0;
	if(player->fixedcolormap)
	{
		fixedcolormap = colormaps+player->fixedcolormap
			*256*sizeof(lighttable_t);
		walllights = scalelightfixed;
		for(i = 0; i < MAXLIGHTSCALE; i++)
		{
			scalelightfixed[i] = fixedcolormap;
		}
	}
	else
	{
		fixedcolormap = 0;
	}
	framecount++;
	validcount++;
	if(BorderNeedRefresh)
	{
		if(setblocks < 10)
		{
			R_DrawViewBorder();
		}
		BorderNeedRefresh = false;
		BorderTopRefresh = false;
		UpdateState |= I_FULLSCRN;
	}
	if(BorderTopRefresh)
	{
		if(setblocks < 10)
		{
			R_DrawTopBorder();
		}
		BorderTopRefresh = false;
		UpdateState |= I_MESSAGES;
	}

#ifdef __NeXT__
	RD_ClearMapWindow ();
#endif
#ifdef __WATCOMC__
	destview = destscreen+(viewwindowx>>2)+viewwindowy*80;
#endif

#if 0
{
static int frame;
memset (screen, frame, SCREENWIDTH*SCREENHEIGHT);
frame++;
}
#endif
}

/*
==============
=
= R_RenderView
=
==============
*/

void R_RenderPlayerView (player_t *player)
{
	R_SetupFrame (player);
	R_ClearClipSegs ();
	R_ClearDrawSegs ();
	R_ClearPlanes ();
	R_ClearSprites ();
	NetUpdate ();					// check for new console commands

	// Make displayed player invisible locally
	if (localQuakeHappening[displayplayer] && gamestate == GS_LEVEL)
	{
		players[displayplayer].mo->flags2 |= MF2_DONTDRAW;
		R_RenderBSPNode (numnodes-1);	// head node is the last node output
		players[displayplayer].mo->flags2 &= ~MF2_DONTDRAW;
	}
	else
	{
		R_RenderBSPNode (numnodes-1);	// head node is the last node output
	}

	NetUpdate ();					// check for new console commands
	R_DrawPlanes ();
	NetUpdate ();					// check for new console commands
	R_DrawMasked ();
	NetUpdate ();					// check for new console commands
}