DoomRTX/neo/engine/framework/DeclTable.cpp

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

IceTech GPL Source Code
Copyright (C) 2026 Justin Marshall 

This file is part of the IceTech GPL Source Code (?IceTech Source Code?).  

IceTech 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 3 of the License, or
(at your option) any later version.

IceTech 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 IceTech Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the IceTech Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the IceTech Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing Justin Marshall, justinmarshall20@gmail.com

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

#include "precompiled.h"
#pragma hdrstop


/*
=================
idDeclTable::TableLookup
=================
*/
float idDeclTable::TableLookup( float index ) const {
	int iIndex;
	float iFrac;
	
	int domain = values.Num() - 1;

	if ( domain <= 1 ) {
		return 1.0f;
	}

	if ( clamp ) {
		index *= (domain-1);
		if ( index >= domain - 1 ) {
			return values[domain - 1];
		} else if ( index <= 0 ) {
			return values[0];
		}
		iIndex = idMath::Ftoi( index );
		iFrac = index - iIndex;
	} else {
		index *= domain;

		if ( index < 0 ) {
			index += domain * idMath::Ceil( -index / domain );
		}

		iIndex = idMath::FtoiFast( idMath::Floor( index ) );
		iFrac = index - iIndex;
		iIndex = iIndex % domain;
	}

	if ( !snap ) {
		// we duplicated the 0 index at the end at creation time, so we
		// don't need to worry about wrapping the filter
		return values[iIndex] * ( 1.0f - iFrac ) + values[iIndex + 1] * iFrac;
	}
	
	return values[iIndex];
}

/*
=================
idDeclTable::Size
=================
*/
size_t idDeclTable::Size( void ) const {
	return sizeof( idDeclTable ) + values.Allocated();
}

/*
=================
idDeclTable::FreeData
=================
*/
void idDeclTable::FreeData( void ) {
	snap = false;
	clamp = false;
	values.Clear();
}

/*
=================
idDeclTable::DefaultDefinition
=================
*/
const char *idDeclTable::DefaultDefinition( void ) const {
	return "{ { 0 } }";
}

/*
=================
idDeclTable::Parse
=================
*/
bool idDeclTable::Parse(const char* text, const int textLength) {
	idLexer src;
	idToken token;
	float v;

	src.LoadMemory(text, textLength, GetFileName(), GetLineNum());
	src.SetFlags(DECL_LEXER_FLAGS);
	src.SkipUntilString("{");

	snap = false;
	clamp = false;

#ifdef QUAKE4
	minValue = idMath::INFINITY;
	maxValue = -1.0e30f;
#endif

	values.Clear();

	while (1) {
		if (!src.ReadToken(&token)) {
			break;
		}

		if (token == "}") {
			break;
		}

		if (token.Icmp("snap") == 0) {
			snap = true;
		}
		else if (token.Icmp("clamp") == 0) {
			clamp = true;
		}
		else if (token.Icmp("{") == 0) {

			while (1) {
				bool errorFlag;

				v = src.ParseFloat(&errorFlag);
				if (errorFlag) {
					// we got something non-numeric
					MakeDefault();
					return false;
				}

				values.Append(v);

#ifdef QUAKE4
				if (v < minValue) {
					minValue = v;
				}
				if (v > maxValue) {
					maxValue = v;
				}
#endif

				src.ReadToken(&token);
				if (token == "}") {
					break;
				}
				if (token == ",") {
					continue;
				}
				src.Warning("expected comma or brace");
				MakeDefault();
				return false;
			}

		}
		else {
			src.Warning("unknown token '%s'", token.c_str());
			MakeDefault();
			return false;
		}
	}

	if (values.Num() <= 0) {
		MakeDefault();
		return false;
	}

	// copy the 0 element to the end, so lerping doesn't
	// need to worry about the wrap case
	float val = values[0];		// template bug requires this to not be in the Append()?
	values.Append(val);

	return true;
}