ABSTRACT.CPP (7750B)
1 // 2 // Copyright 2020 Electronic Arts Inc. 3 // 4 // TiberianDawn.DLL and RedAlert.dll and corresponding source code is free 5 // software: you can redistribute it and/or modify it under the terms of 6 // the GNU General Public License as published by the Free Software Foundation, 7 // either version 3 of the License, or (at your option) any later version. 8 9 // TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed 10 // in the hope that it will be useful, but with permitted additional restrictions 11 // under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT 12 // distributed with this program. You should have received a copy of the 13 // GNU General Public License along with permitted additional restrictions 14 // with this program. If not, see https://github.com/electronicarts/CnC_Remastered_Collection 15 16 /* $Header: F:\projects\c&c\vcs\code\abstract.cpv 2.20 16 Oct 1995 16:49:04 JOE_BOSTIC $ */ 17 /*********************************************************************************************** 18 *** 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 *** 19 *********************************************************************************************** 20 * * 21 * Project Name : Command & Conquer * 22 * * 23 * File Name : ABSTRACT.CPP * 24 * * 25 * Programmer : Joe L. Bostic * 26 * * 27 * Start Date : 01/26/95 * 28 * * 29 * Last Update : May 22, 1995 [JLB] * 30 * * 31 *---------------------------------------------------------------------------------------------* 32 * Functions: * 33 * AbstractClass::Distance -- Determines distance to target. * 34 * AbstractTypeClass::AbstractTypeClass -- Constructor for abstract type objects. * 35 * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 36 37 #include "function.h" 38 39 40 /*********************************************************************************************** 41 * AbstractClass::Distance -- Determines distance to target. * 42 * * 43 * This will determine the distance (direct line) to the target. The distance is in * 44 * 'leptons'. This routine is typically used for weapon range checks. * 45 * * 46 * INPUT: target -- The target to determine range to. * 47 * * 48 * OUTPUT: Returns with the range to the specified target (in leptons). * 49 * * 50 * WARNINGS: none * 51 * * 52 * HISTORY: * 53 * 08/17/1994 JLB : Created. * 54 *=============================================================================================*/ 55 int AbstractClass::Distance(TARGET target) const 56 { 57 /* 58 ** Should subtract a fudge-factor distance for building targets. 59 */ 60 BuildingClass *obj = As_Building(target); 61 int dist = Distance(As_Coord(target)); 62 63 /* 64 ** If the object is a building the adjust it by the average radius 65 ** of the object. 66 */ 67 if (obj && obj->IsActive) { 68 dist -= ((obj->Class->Width() + obj->Class->Height()) * (0x100 / 4)); 69 if (dist < 0) dist = 0; 70 } 71 72 /* 73 ** Return the distance to the target 74 */ 75 return(dist); 76 } 77 78 79 /*********************************************************************************************** 80 * AbstractTypeClass::AbstractTypeClass -- Constructor for abstract type objects. * 81 * * 82 * This is the constructor for AbstractTypeClass objects. It initializes the INI name and * 83 * the text name for this object type. * 84 * * 85 * INPUT: name -- Text number for the full name of the object. * 86 * * 87 * ini -- The ini name for this object type. * 88 * * 89 * OUTPUT: none * 90 * * 91 * WARNINGS: none * 92 * * 93 * HISTORY: * 94 * 05/22/1995 JLB : Created. * 95 *=============================================================================================*/ 96 AbstractTypeClass::AbstractTypeClass(int name, char const * ini) 97 { 98 Name = name; 99 strncpy((char *)IniName, ini, sizeof(IniName)); 100 ((char &)IniName[sizeof(IniName)-1]) = '\0'; 101 } 102 103 RTTIType AbstractTypeClass::What_Am_I(void) const {return RTTI_ABSTRACTTYPE;}; 104 COORDINATE AbstractTypeClass::Coord_Fixup(COORDINATE coord) const {return coord;} 105 int AbstractTypeClass::Full_Name(void) const {return Name;}; 106 unsigned short AbstractTypeClass::Get_Ownable(void) const {return 0xffff;}; 107 108 109 110 111 void AbstractClass::Delete_This(void) 112 { 113 /* 114 ** Apparently Watcom preserved the vtable through the virtual destructor chain, otherwise C&C would crash all the time. 115 ** 116 ** MSVC doesn't. It overwrites the vtable pointer with the vtable of the class currently being destructed - presumably to 117 ** prevent virtual functions of the classes already destructed from being called. 118 ** 119 ** So this is a hacky workaround to restore the original vtable pointer after the destructor chain has finished, for when the 120 ** C&C code wants to call a virtual function on an object it just 'deleted'. 121 ** 122 ** ST - 1/9/2019 6:02PM 123 */ 124 unsigned long *this_ptr = (unsigned long*) this; 125 unsigned long vtable_ptr = *this_ptr; 126 127 /* 128 ** delete this calls the operator delete, it doesn't actually deallocate the memory. 129 */ 130 delete this; 131 132 *this_ptr = vtable_ptr; 133 }