r_things.c

使用Doom引擎开发的著名游戏《毁灭巫师》的源代码。

//**************************************************************************
//**
//** r_things.c : Heretic 2 : Raven Software, Corp.
//**
//** $RCSfile: r_things.c,v $
//** $Revision: 1.26 $
//** $Date: 96/01/06 18:37:42 $
//** $Author: bgokey $
//**
//**************************************************************************

#include <stdio.h>
#include <stdlib.h>
#include "h2def.h"
#include "r_local.h"

void R_DrawColumn (void);
void R_DrawFuzzColumn (void);
void R_DrawAltFuzzColumn(void);
//void R_DrawTranslatedAltFuzzColumn(void);

typedef struct
{
	int		x1, x2;

	int		column;
	int		topclip;
	int		bottomclip;
} maskdraw_t;

/*

Sprite rotation 0 is facing the viewer, rotation 1 is one angle turn CLOCKWISE around the axis.
This is not the same as the angle, which increases counter clockwise
(protractor).  There was a lot of stuff grabbed wrong, so I changed it...

*/


fixed_t		pspritescale, pspriteiscale;

lighttable_t	**spritelights;

// constant arrays used for psprite clipping and initializing clipping
short	negonearray[SCREENWIDTH];
short	screenheightarray[SCREENWIDTH];

boolean LevelUseFullBright;
/*
===============================================================================

						INITIALIZATION FUNCTIONS

===============================================================================
*/

// variables used to look up and range check thing_t sprites patches
spritedef_t		*sprites;
int				numsprites;

spriteframe_t	sprtemp[30];
int				maxframe;
char			*spritename;



/*
=================
=
= R_InstallSpriteLump
=
= Local function for R_InitSprites
=================
*/

void R_InstallSpriteLump (int lump, unsigned frame, unsigned rotation, boolean flipped)
{
	int		r;

	if (frame >= 30 || rotation > 8)
		I_Error ("R_InstallSpriteLump: Bad frame characters in lump %i", lump);

	if ((int)frame > maxframe)
		maxframe = frame;

	if (rotation == 0)
	{
// the lump should be used for all rotations
		if (sprtemp[frame].rotate == false)
			I_Error ("R_InitSprites: Sprite %s frame %c has multip rot=0 lump"
			, spritename, 'A'+frame);
		if (sprtemp[frame].rotate == true)
			I_Error ("R_InitSprites: Sprite %s frame %c has rotations and a rot=0 lump"
			, spritename, 'A'+frame);

		sprtemp[frame].rotate = false;
		for (r=0 ; r<8 ; r++)
		{
			sprtemp[frame].lump[r] = lump - firstspritelump;
			sprtemp[frame].flip[r] = (byte)flipped;
		}
		return;
	}

// the lump is only used for one rotation
	if (sprtemp[frame].rotate == false)
		I_Error ("R_InitSprites: Sprite %s frame %c has rotations and a rot=0 lump"
		, spritename, 'A'+frame);

	sprtemp[frame].rotate = true;

	rotation--;		// make 0 based
	if (sprtemp[frame].lump[rotation] != -1)
		I_Error ("R_InitSprites: Sprite %s : %c : %c has two lumps mapped to it"
		,spritename, 'A'+frame, '1'+rotation);

	sprtemp[frame].lump[rotation] = lump - firstspritelump;
	sprtemp[frame].flip[rotation] = (byte)flipped;
}

/*
=================
=
= R_InitSpriteDefs
=
= Pass a null terminated list of sprite names (4 chars exactly) to be used
= Builds the sprite rotation matrixes to account for horizontally flipped
= sprites.  Will report an error if the lumps are inconsistant
=
Only called at startup
=
= Sprite lump names are 4 characters for the actor, a letter for the frame,
= and a number for the rotation, A sprite that is flippable will have an
= additional letter/number appended.  The rotation character can be 0 to
= signify no rotations
=================
*/

void R_InitSpriteDefs (char **namelist)
{
	char		**check;
	int		i, l, intname, frame, rotation;
	int		start, end;

// count the number of sprite names
	check = namelist;
	while (*check != NULL)
		check++;
	numsprites = check-namelist;

	if (!numsprites)
		return;

	sprites = Z_Malloc(numsprites *sizeof(*sprites), PU_STATIC, NULL);

	start = firstspritelump-1;
	end = lastspritelump+1;

// scan all the lump names for each of the names, noting the highest
// frame letter
// Just compare 4 characters as ints
	for (i=0 ; i<numsprites ; i++)
	{
		spritename = namelist[i];
		memset (sprtemp,-1, sizeof(sprtemp));

		maxframe = -1;
		intname = *(int *)namelist[i];

		//
		// scan the lumps, filling in the frames for whatever is found
		//
		for (l=start+1 ; l<end ; l++)
			if (*(int *)lumpinfo[l].name == intname)
			{
				frame = lumpinfo[l].name[4] - 'A';
				rotation = lumpinfo[l].name[5] - '0';
				R_InstallSpriteLump (l, frame, rotation, false);
				if (lumpinfo[l].name[6])
				{
					frame = lumpinfo[l].name[6] - 'A';
					rotation = lumpinfo[l].name[7] - '0';
					R_InstallSpriteLump (l, frame, rotation, true);
				}
			}

		//
		// check the frames that were found for completeness
		//
		if (maxframe == -1)
		{
			//continue;
			sprites[i].numframes = 0;
			if (shareware)
				continue;
			I_Error ("R_InitSprites: No lumps found for sprite %s"
			,namelist[i]);
		}

		maxframe++;
		for (frame = 0 ; frame < maxframe ; frame++)
		{
			switch ((int)sprtemp[frame].rotate)
			{
			case -1:	// no rotations were found for that frame at all
				I_Error ("R_InitSprites: No patches found for %s frame %c"
				, namelist[i], frame+'A');
			case 0:	// only the first rotation is needed
				break;

			case 1:	// must have all 8 frames
				for (rotation=0 ; rotation<8 ; rotation++)
					if (sprtemp[frame].lump[rotation] == -1)
						I_Error ("R_InitSprites: Sprite %s frame %c is missing rotations"
						, namelist[i], frame+'A');
			}
		}

		//
		// allocate space for the frames present and copy sprtemp to it
		//
		sprites[i].numframes = maxframe;
		sprites[i].spriteframes =
			Z_Malloc (maxframe * sizeof(spriteframe_t), PU_STATIC, NULL);
		memcpy (sprites[i].spriteframes, sprtemp, maxframe*sizeof(spriteframe_t));
	}

}


/*
===============================================================================

							GAME FUNCTIONS

===============================================================================
*/

vissprite_t	vissprites[MAXVISSPRITES], *vissprite_p;
int			newvissprite;


/*
===================
=
= R_InitSprites
=
= Called at program start
===================
*/

void R_InitSprites (char **namelist)
{
	int		i;

	for (i=0 ; i<SCREENWIDTH ; i++)
	{
		negonearray[i] = -1;
	}

	R_InitSpriteDefs (namelist);
}


/*
===================
=
= R_ClearSprites
=
= Called at frame start
===================
*/

void R_ClearSprites (void)
{
	vissprite_p = vissprites;
}


/*
===================
=
= R_NewVisSprite
=
===================
*/

vissprite_t		overflowsprite;

vissprite_t *R_NewVisSprite (void)
{
	if (vissprite_p == &vissprites[MAXVISSPRITES])
		return &overflowsprite;
	vissprite_p++;
	return vissprite_p-1;
}


/*
================
=
= R_DrawMaskedColumn
=
= Used for sprites and masked mid textures
================
*/

short		*mfloorclip;
short		*mceilingclip;
fixed_t		spryscale;
fixed_t		sprtopscreen;
fixed_t		sprbotscreen;

void R_DrawMaskedColumn (column_t *column, signed int baseclip)
{
	int		topscreen, bottomscreen;
	fixed_t	basetexturemid;

	basetexturemid = dc_texturemid;

	for ( ; column->topdelta != 0xff ; )
	{
// calculate unclipped screen coordinates for post
		topscreen = sprtopscreen + spryscale*column->topdelta;
		bottomscreen = topscreen + spryscale*column->length;
		dc_yl = (topscreen+FRACUNIT-1)>>FRACBITS;
		dc_yh = (bottomscreen-1)>>FRACBITS;

		if (dc_yh >= mfloorclip[dc_x])
			dc_yh = mfloorclip[dc_x]-1;
		if (dc_yl <= mceilingclip[dc_x])
			dc_yl = mceilingclip[dc_x]+1;

		if(dc_yh >= baseclip && baseclip != -1)
			dc_yh = baseclip;

		if (dc_yl <= dc_yh)
		{
			dc_source = (byte *)column + 3;
			dc_texturemid = basetexturemid - (column->topdelta<<FRACBITS);
//			dc_source = (byte *)column + 3 - column->topdelta;
			colfunc ();		// either R_DrawColumn or R_DrawFuzzColumn
		}
		column = (column_t *)(  (byte *)column + column->length + 4);
	}

	dc_texturemid = basetexturemid;
}


/*
================
=
= R_DrawVisSprite
=
= mfloorclip and mceilingclip should also be set
================
*/

void R_DrawVisSprite (vissprite_t *vis, int x1, int x2)
{
	column_t	*column;
	int			texturecolumn;
	fixed_t		frac;
	patch_t		*patch;
	fixed_t		baseclip;


	patch = W_CacheLumpNum(vis->patch+firstspritelump, PU_CACHE);

	dc_colormap = vis->colormap;

//	if(!dc_colormap)
//		colfunc = fuzzcolfunc;	// NULL colormap = shadow draw

	if(vis->mobjflags&(MF_SHADOW|MF_ALTSHADOW))
	{
		if(vis->mobjflags&MF_TRANSLATION)
		{
			colfunc = R_DrawTranslatedFuzzColumn;
			dc_translation = translationtables-256
				+vis->class*((MAXPLAYERS-1)*256)+
				((vis->mobjflags&MF_TRANSLATION)>>(MF_TRANSSHIFT-8));
		}
		else if(vis->mobjflags&MF_SHADOW)
		{ // Draw using shadow column function
			colfunc = fuzzcolfunc;
		}
		else
		{
			colfunc = R_DrawAltFuzzColumn;
		}
	}
	else if(vis->mobjflags&MF_TRANSLATION)
	{
		// Draw using translated column function
		colfunc = R_DrawTranslatedColumn;
		dc_translation = translationtables-256
			+vis->class*((MAXPLAYERS-1)*256)+
			((vis->mobjflags&MF_TRANSLATION)>>(MF_TRANSSHIFT-8));
	}

	dc_iscale = abs(vis->xiscale)>>detailshift;
	dc_texturemid = vis->texturemid;
	frac = vis->startfrac;
	spryscale = vis->scale;

	sprtopscreen = centeryfrac - FixedMul(dc_texturemid,spryscale);

	// check to see if vissprite is a weapon
	if(vis->psprite)
	{
		dc_texturemid += FixedMul(((centery-viewheight/2)<<FRACBITS),
			vis->xiscale);
		sprtopscreen += (viewheight/2-centery)<<FRACBITS;
	}

	if(vis->floorclip && !vis->psprite)
	{
		sprbotscreen = sprtopscreen+FixedMul(patch->height<<FRACBITS,
			spryscale);
		baseclip = (sprbotscreen-FixedMul(vis->floorclip, 
			spryscale))>>FRACBITS;
	}
	else
	{
		baseclip = -1;
	}

	for (dc_x=vis->x1 ; dc_x<=vis->x2 ; dc_x++, frac += vis->xiscale)
	{
		texturecolumn = frac>>FRACBITS;
#ifdef RANGECHECK
		if (texturecolumn < 0 || texturecolumn >= SHORT(patch->width))
			I_Error ("R_DrawSpriteRange: bad texturecolumn");
#endif
		column = (column_t *) ((byte *)patch +
		 LONG(patch->columnofs[texturecolumn]));
		 R_DrawMaskedColumn (column, baseclip);
	}

	colfunc = basecolfunc;
}



/*
===================
=
= R_ProjectSprite
=
= Generates a vissprite for a thing if it might be visible
=
===================
*/

void R_ProjectSprite (mobj_t *thing)
{
	fixed_t		trx,try;
	fixed_t		gxt,gyt;
	fixed_t		tx,tz;
	fixed_t		xscale;
	int			x1, x2;
	spritedef_t	*sprdef;
	spriteframe_t	*sprframe;
	int			lump;
	unsigned	rot;
	boolean		flip;
	int			index;
	vissprite_t	*vis;
	angle_t		ang;
	fixed_t		iscale;

	if(thing->flags2&MF2_DONTDRAW)
	{ // Never make a vissprite when MF2_DONTDRAW is flagged.
		return;
	}

//
// transform the origin point
//
	trx = thing->x - viewx;
	try = thing->y - viewy;

	gxt = FixedMul(trx,viewcos);
	gyt = -FixedMul(try,viewsin);
	tz = gxt-gyt;

	if (tz < MINZ)
		return;		// thing is behind view plane
	xscale = FixedDiv(projection, tz);

	gxt = -FixedMul(trx,viewsin);
	gyt = FixedMul(try,viewcos);
	tx = -(gyt+gxt);
	
	if (abs(tx)>(tz<<2))
		return;		// too far off the side

//
// decide which patch to use for sprite reletive to player
//
#ifdef RANGECHECK
	if ((unsigned)thing->sprite >= numsprites)
		I_Error ("R_ProjectSprite: invalid sprite number %i ",thing->sprite);
#endif
	sprdef = &sprites[thing->sprite];
#ifdef RANGECHECK
	if ( (thing->frame&FF_FRAMEMASK) >= sprdef->numframes )
		I_Error ("R_ProjectSprite: invalid sprite frame %i : %i "
		,thing->sprite, thing->frame);
#endif
	sprframe = &sprdef->spriteframes[ thing->frame & FF_FRAMEMASK];

	if (sprframe->rotate)
	{	// choose a different rotation based on player view
		ang = R_PointToAngle (thing->x, thing->y);