CnC_Remastered_Collection/TIBERIANDAWN/COMBAT.CPP

234 lines
12 KiB
C++

//
// Copyright 2020 Electronic Arts Inc.
//
// TiberianDawn.DLL and RedAlert.dll and corresponding 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.
// TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed
// in the hope that it will be useful, but with permitted additional restrictions
// under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT
// distributed with this program. You should have received a copy of the
// GNU General Public License along with permitted additional restrictions
// with this program. If not, see https://github.com/electronicarts/CnC_Remastered_Collection
/* $Header: F:\projects\c&c\vcs\code\combat.cpv 2.17 16 Oct 1995 16:48:32 JOE_BOSTIC $ */
/***********************************************************************************************
*** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S ***
***********************************************************************************************
* *
* Project Name : Command & Conquer *
* *
* File Name : COMBAT.CPP *
* *
* Programmer : Joe L. Bostic *
* *
* Start Date : September 19, 1994 *
* *
* Last Update : January 1, 1995 [JLB] *
* *
*---------------------------------------------------------------------------------------------*
* Functions: *
* Explosion_Damage -- Inflict an explosion damage affect. *
* Modify_Damage -- Adjusts damage to reflect the nature of the target. *
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#include "function.h"
int Modify_Damage(int damage, WarheadType warhead, ArmorType armor);
void Explosion_Damage(COORDINATE coord, unsigned strength, TechnoClass *source, WarheadType warhead);
/***********************************************************************************************
* Modify_Damage -- Adjusts damage to reflect the nature of the target. *
* *
* This routine is the core of combat tactics. It implements the *
* affect various armor types have against various weapon types. By *
* careful exploitation of this table, tactical advantage can be *
* obtained. *
* *
* INPUT: damage -- The damage points to process. *
* *
* warhead -- The source of the damage points. *
* *
* armor -- The type of armor defending against the damage. *
* *
* distance -- The distance (in leptons) from the source of the damage. *
* *
* OUTPUT: Returns with the adjusted damage points to inflict upon the *
* target. *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 04/16/1994 JLB : Created. *
* 04/17/1994 JLB : Always does a minimum of damage. *
* 01/01/1995 JLB : Takes into account distance from damage source. *
*=============================================================================================*/
int Modify_Damage(int damage, WarheadType warhead, ArmorType armor, int distance)
{
/*
** If there is no raw damage value to start with, then
** there can be no modified damage either.
*/
if (Special.IsInert || !damage || warhead == WARHEAD_NONE) return(0);
WarheadTypeClass const * whead = &Warheads[warhead];
damage = Fixed_To_Cardinal(damage, whead->Modifier[armor]);
/*
** Reduce damage according to the distance from the impact point.
*/
if (damage) {
// if (distance < 0x0010) damage *= 2; // Double damage for direct hits.
distance >>= whead->SpreadFactor;
distance = Bound(distance, 0, 16);
damage >>= distance;
}
/*
** If damage was indicated, then it should never drop below one damage point regardless
** of modifiers. This allows a very weak attacker to eventually destroy anything it
** fires upon, given enough time.
*/
return(damage);
}
/***********************************************************************************************
* Explosion_Damage -- Inflict an explosion damage affect. *
* *
* Processes the collateral damage affects typically caused by an *
* explosion. *
* *
* INPUT: coord -- The coordinate of ground zero. *
* *
* strength -- Raw damage points at ground zero. *
* *
* source -- Source of the explosion (who is responsible). *
* *
* warhead -- The kind of explosion to process. *
* *
* OUTPUT: none *
* *
* WARNINGS: This routine can consume some time and will affect the AI *
* of nearby enemy units (possibly). *
* *
* HISTORY: *
* 08/16/1991 JLB : Created. *
* 11/30/1991 JLB : Uses coordinate system. *
* 12/27/1991 JLB : Radius of explosion damage effect. *
* 04/13/1994 JLB : Streamlined. *
* 04/16/1994 JLB : Warhead damage type modifier. *
* 04/17/1994 JLB : Cleaned up. *
* 06/20/1994 JLB : Uses object pointers to distribute damage. *
* 06/20/1994 JLB : Source is a pointer. *
*=============================================================================================*/
void Explosion_Damage(COORDINATE coord, unsigned strength, TechnoClass * source, WarheadType warhead)
{
CELL cell; // Cell number under explosion.
ObjectClass * object; // Working object pointer.
ObjectClass * objects[32]; // Maximum number of objects that can be damaged.
int distance; // Distance to unit.
int range; // Damage effect radius.
int index;
int count; // Number of vehicle IDs in list.
if (!strength || Special.IsInert || warhead == WARHEAD_NONE) return;
WarheadTypeClass const * whead = &Warheads[warhead];
range = ICON_LEPTON_W + (ICON_LEPTON_W >> 1);
cell = Coord_Cell(coord);
if ((unsigned)cell >= MAP_CELL_TOTAL) return;
// if (!Map.In_Radar(cell)) return;
CellClass * cellptr = &Map[cell];
ObjectClass * impacto = cellptr->Cell_Occupier();
/*
** Fill the list of unit IDs that will have damage
** assessed upon them. The units can be lifted from
** the cell data directly.
*/
count = 0;
for (FacingType i = FACING_NONE; i < FACING_COUNT; i++) {
/*
** Fetch a pointer to the cell to examine. This is either
** an adjacent cell or the center cell. Damage never spills
** further than one cell away.
*/
if (i != FACING_NONE) {
cellptr = Map[cell].Adjacent_Cell(i);
if (!cellptr) continue;
}
/*
** Add all objects in this cell to the list of objects to possibly apply
** damage to. The list stops building when the object pointer list becomes
** full. Do not include overlapping objects; selection state can affect
** the overlappers, and this causes multiplayer games to go out of sync.
*/
object = cellptr->Cell_Occupier();
while (object) {
if (!object->IsToDamage && object != source) {
object->IsToDamage = true;
objects[count++] = object;
if (count >= (sizeof(objects)/sizeof(objects[0]))) break;
}
object = object->Next;
}
if (count >= (sizeof(objects)/sizeof(objects[0]))) break;
}
/*
** Sweep through the units to be damaged and damage them. When damaging
** buildings, consider a hit on any cell the building occupies as if it
** were a direct hit on the building's center.
*/
for (index = 0; index < count; index++) {
object = objects[index];
object->IsToDamage = false;
if (object->What_Am_I() == RTTI_BUILDING && impacto == object) {
distance = 0;
} else {
distance = Distance(coord, object->Center_Coord());
}
if (object->IsDown && !object->IsInLimbo && distance < range) {
int damage = strength;
/*
** High explosive does double damage against aircraft.
*/
if (warhead == WARHEAD_HE && object->What_Am_I() == RTTI_AIRCRAFT) {
damage *= 2;
}
/*
** Apply the damage to the object.
*/
if (damage) {
object->Take_Damage(damage, distance, warhead, source);
}
}
}
/*
** If there is a wall present at this location, it may be destroyed. Check to
** make sure that the warhead is of the kind that can destroy walls.
*/
cellptr = &Map[cell];
cellptr->Reduce_Tiberium(strength / 10);
if (cellptr->Overlay != OVERLAY_NONE) {
OverlayTypeClass const * optr = &OverlayTypeClass::As_Reference(cellptr->Overlay);
if (optr->IsWall) {
if (whead->IsWallDestroyer || (whead->IsWoodDestroyer && optr->IsWooden)) {
Map[cell].Reduce_Wall(strength);
}
}
}
}