tr_shader.c

3D 游戏界的大牛人 John Carmack 终于放出了 Q3 的源代码

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
#include "tr_local.h"

// tr_shader.c -- this file deals with the parsing and definition of shaders

static char *s_shaderText;

// the shader is parsed into these global variables, then copied into
// dynamically allocated memory if it is valid.
static	shaderStage_t	stages[MAX_SHADER_STAGES];		
static	shader_t		shader;
static	texModInfo_t	texMods[MAX_SHADER_STAGES][TR_MAX_TEXMODS];
static	qboolean		deferLoad;

#define FILE_HASH_SIZE		1024
static	shader_t*		hashTable[FILE_HASH_SIZE];

#define MAX_SHADERTEXT_HASH		2048
static char **shaderTextHashTable[MAX_SHADERTEXT_HASH];

/*
================
return a hash value for the filename
================
*/
static long generateHashValue( const char *fname, const int size ) {
	int		i;
	long	hash;
	char	letter;

	hash = 0;
	i = 0;
	while (fname[i] != '\0') {
		letter = tolower(fname[i]);
		if (letter =='.') break;				// don't include extension
		if (letter =='\\') letter = '/';		// damn path names
		if (letter == PATH_SEP) letter = '/';		// damn path names
		hash+=(long)(letter)*(i+119);
		i++;
	}
	hash = (hash ^ (hash >> 10) ^ (hash >> 20));
	hash &= (size-1);
	return hash;
}

void R_RemapShader(const char *shaderName, const char *newShaderName, const char *timeOffset) {
	char		strippedName[MAX_QPATH];
	int			hash;
	shader_t	*sh, *sh2;
	qhandle_t	h;

	sh = R_FindShaderByName( shaderName );
	if (sh == NULL || sh == tr.defaultShader) {
		h = RE_RegisterShaderLightMap(shaderName, 0);
		sh = R_GetShaderByHandle(h);
	}
	if (sh == NULL || sh == tr.defaultShader) {
		ri.Printf( PRINT_WARNING, "WARNING: R_RemapShader: shader %s not found\n", shaderName );
		return;
	}

	sh2 = R_FindShaderByName( newShaderName );
	if (sh2 == NULL || sh2 == tr.defaultShader) {
		h = RE_RegisterShaderLightMap(newShaderName, 0);
		sh2 = R_GetShaderByHandle(h);
	}

	if (sh2 == NULL || sh2 == tr.defaultShader) {
		ri.Printf( PRINT_WARNING, "WARNING: R_RemapShader: new shader %s not found\n", newShaderName );
		return;
	}

	// remap all the shaders with the given name
	// even tho they might have different lightmaps
	COM_StripExtension( shaderName, strippedName );
	hash = generateHashValue(strippedName, FILE_HASH_SIZE);
	for (sh = hashTable[hash]; sh; sh = sh->next) {
		if (Q_stricmp(sh->name, strippedName) == 0) {
			if (sh != sh2) {
				sh->remappedShader = sh2;
			} else {
				sh->remappedShader = NULL;
			}
		}
	}
	if (timeOffset) {
		sh2->timeOffset = atof(timeOffset);
	}
}

/*
===============
ParseVector
===============
*/
static qboolean ParseVector( char **text, int count, float *v ) {
	char	*token;
	int		i;

	// FIXME: spaces are currently required after parens, should change parseext...
	token = COM_ParseExt( text, qfalse );
	if ( strcmp( token, "(" ) ) {
		ri.Printf( PRINT_WARNING, "WARNING: missing parenthesis in shader '%s'\n", shader.name );
		return qfalse;
	}

	for ( i = 0 ; i < count ; i++ ) {
		token = COM_ParseExt( text, qfalse );
		if ( !token[0] ) {
			ri.Printf( PRINT_WARNING, "WARNING: missing vector element in shader '%s'\n", shader.name );
			return qfalse;
		}
		v[i] = atof( token );
	}

	token = COM_ParseExt( text, qfalse );
	if ( strcmp( token, ")" ) ) {
		ri.Printf( PRINT_WARNING, "WARNING: missing parenthesis in shader '%s'\n", shader.name );
		return qfalse;
	}

	return qtrue;
}


/*
===============
NameToAFunc
===============
*/
static unsigned NameToAFunc( const char *funcname )
{	
	if ( !Q_stricmp( funcname, "GT0" ) )
	{
		return GLS_ATEST_GT_0;
	}
	else if ( !Q_stricmp( funcname, "LT128" ) )
	{
		return GLS_ATEST_LT_80;
	}
	else if ( !Q_stricmp( funcname, "GE128" ) )
	{
		return GLS_ATEST_GE_80;
	}

	ri.Printf( PRINT_WARNING, "WARNING: invalid alphaFunc name '%s' in shader '%s'\n", funcname, shader.name );
	return 0;
}


/*
===============
NameToSrcBlendMode
===============
*/
static int NameToSrcBlendMode( const char *name )
{
	if ( !Q_stricmp( name, "GL_ONE" ) )
	{
		return GLS_SRCBLEND_ONE;
	}
	else if ( !Q_stricmp( name, "GL_ZERO" ) )
	{
		return GLS_SRCBLEND_ZERO;
	}
	else if ( !Q_stricmp( name, "GL_DST_COLOR" ) )
	{
		return GLS_SRCBLEND_DST_COLOR;
	}
	else if ( !Q_stricmp( name, "GL_ONE_MINUS_DST_COLOR" ) )
	{
		return GLS_SRCBLEND_ONE_MINUS_DST_COLOR;
	}
	else if ( !Q_stricmp( name, "GL_SRC_ALPHA" ) )
	{
		return GLS_SRCBLEND_SRC_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_ONE_MINUS_SRC_ALPHA" ) )
	{
		return GLS_SRCBLEND_ONE_MINUS_SRC_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_DST_ALPHA" ) )
	{
		return GLS_SRCBLEND_DST_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_ONE_MINUS_DST_ALPHA" ) )
	{
		return GLS_SRCBLEND_ONE_MINUS_DST_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_SRC_ALPHA_SATURATE" ) )
	{
		return GLS_SRCBLEND_ALPHA_SATURATE;
	}

	ri.Printf( PRINT_WARNING, "WARNING: unknown blend mode '%s' in shader '%s', substituting GL_ONE\n", name, shader.name );
	return GLS_SRCBLEND_ONE;
}

/*
===============
NameToDstBlendMode
===============
*/
static int NameToDstBlendMode( const char *name )
{
	if ( !Q_stricmp( name, "GL_ONE" ) )
	{
		return GLS_DSTBLEND_ONE;
	}
	else if ( !Q_stricmp( name, "GL_ZERO" ) )
	{
		return GLS_DSTBLEND_ZERO;
	}
	else if ( !Q_stricmp( name, "GL_SRC_ALPHA" ) )
	{
		return GLS_DSTBLEND_SRC_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_ONE_MINUS_SRC_ALPHA" ) )
	{
		return GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_DST_ALPHA" ) )
	{
		return GLS_DSTBLEND_DST_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_ONE_MINUS_DST_ALPHA" ) )
	{
		return GLS_DSTBLEND_ONE_MINUS_DST_ALPHA;
	}
	else if ( !Q_stricmp( name, "GL_SRC_COLOR" ) )
	{
		return GLS_DSTBLEND_SRC_COLOR;
	}
	else if ( !Q_stricmp( name, "GL_ONE_MINUS_SRC_COLOR" ) )
	{
		return GLS_DSTBLEND_ONE_MINUS_SRC_COLOR;
	}

	ri.Printf( PRINT_WARNING, "WARNING: unknown blend mode '%s' in shader '%s', substituting GL_ONE\n", name, shader.name );
	return GLS_DSTBLEND_ONE;
}

/*
===============
NameToGenFunc
===============
*/
static genFunc_t NameToGenFunc( const char *funcname )
{
	if ( !Q_stricmp( funcname, "sin" ) )
	{
		return GF_SIN;
	}
	else if ( !Q_stricmp( funcname, "square" ) )
	{
		return GF_SQUARE;
	}
	else if ( !Q_stricmp( funcname, "triangle" ) )
	{
		return GF_TRIANGLE;
	}
	else if ( !Q_stricmp( funcname, "sawtooth" ) )
	{
		return GF_SAWTOOTH;
	}
	else if ( !Q_stricmp( funcname, "inversesawtooth" ) )
	{
		return GF_INVERSE_SAWTOOTH;
	}
	else if ( !Q_stricmp( funcname, "noise" ) )
	{
		return GF_NOISE;
	}

	ri.Printf( PRINT_WARNING, "WARNING: invalid genfunc name '%s' in shader '%s'\n", funcname, shader.name );
	return GF_SIN;
}


/*
===================
ParseWaveForm
===================
*/
static void ParseWaveForm( char **text, waveForm_t *wave )
{
	char *token;

	token = COM_ParseExt( text, qfalse );
	if ( token[0] == 0 )
	{
		ri.Printf( PRINT_WARNING, "WARNING: missing waveform parm in shader '%s'\n", shader.name );
		return;
	}
	wave->func = NameToGenFunc( token );

	// BASE, AMP, PHASE, FREQ
	token = COM_ParseExt( text, qfalse );
	if ( token[0] == 0 )
	{
		ri.Printf( PRINT_WARNING, "WARNING: missing waveform parm in shader '%s'\n", shader.name );
		return;
	}
	wave->base = atof( token );

	token = COM_ParseExt( text, qfalse );
	if ( token[0] == 0 )
	{
		ri.Printf( PRINT_WARNING, "WARNING: missing waveform parm in shader '%s'\n", shader.name );
		return;
	}
	wave->amplitude = atof( token );

	token = COM_ParseExt( text, qfalse );
	if ( token[0] == 0 )
	{
		ri.Printf( PRINT_WARNING, "WARNING: missing waveform parm in shader '%s'\n", shader.name );
		return;
	}
	wave->phase = atof( token );

	token = COM_ParseExt( text, qfalse );
	if ( token[0] == 0 )
	{
		ri.Printf( PRINT_WARNING, "WARNING: missing waveform parm in shader '%s'\n", shader.name );
		return;
	}
	wave->frequency = atof( token );
}


/*
===================
ParseTexMod
===================
*/
static void ParseTexMod( char *_text, shaderStage_t *stage )
{
	const char *token;
	char **text = &_text;
	texModInfo_t *tmi;

	if ( stage->bundle[0].numTexMods == TR_MAX_TEXMODS ) {
		ri.Error( ERR_DROP, "ERROR: too many tcMod stages in shader '%s'\n", shader.name );
		return;
	}

	tmi = &stage->bundle[0].texMods[stage->bundle[0].numTexMods];
	stage->bundle[0].numTexMods++;

	token = COM_ParseExt( text, qfalse );

	//
	// turb
	//
	if ( !Q_stricmp( token, "turb" ) )
	{
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing tcMod turb parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.base = atof( token );
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing tcMod turb in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.amplitude = atof( token );
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing tcMod turb in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.phase = atof( token );
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing tcMod turb in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.frequency = atof( token );

		tmi->type = TMOD_TURBULENT;
	}
	//
	// scale
	//
	else if ( !Q_stricmp( token, "scale" ) )
	{
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing scale parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->scale[0] = atof( token );

		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing scale parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->scale[1] = atof( token );
		tmi->type = TMOD_SCALE;
	}
	//
	// scroll
	//
	else if ( !Q_stricmp( token, "scroll" ) )
	{
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing scale scroll parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->scroll[0] = atof( token );
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing scale scroll parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->scroll[1] = atof( token );
		tmi->type = TMOD_SCROLL;
	}
	//
	// stretch
	//
	else if ( !Q_stricmp( token, "stretch" ) )
	{
		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing stretch parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.func = NameToGenFunc( token );

		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing stretch parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.base = atof( token );

		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing stretch parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.amplitude = atof( token );

		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing stretch parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.phase = atof( token );

		token = COM_ParseExt( text, qfalse );
		if ( token[0] == 0 )
		{
			ri.Printf( PRINT_WARNING, "WARNING: missing stretch parms in shader '%s'\n", shader.name );
			return;
		}
		tmi->wave.frequency = atof( token );