/*
** Command & Conquer Generals Zero Hour(tm)
** Copyright 2025 Electronic Arts Inc.
**
** This program 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.
**
** This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
/***********************************************************************************************
*** 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 : WWMath *
* *
* $Archive:: /Commando/Code/wwmath/matrix4.cpp $*
* *
* Author:: Greg_h *
* *
* $Modtime:: 11/13/99 10:50a $*
* *
* $Revision:: 5 $*
* *
*---------------------------------------------------------------------------------------------*
* Functions: *
* Matrix4::Multiply -- Multiply two Matrix4's together *
* Matrix4::Multiply -- Multiply a Matrix3D * Matrix4 *
* Matrix4::Multiply -- Multiply a Matrix4 * Matrix3D *
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#include "matrix4.h"
#include <assert.h>
/***********************************************************************************************
* Matrix4::Multiply -- Multiply two Matrix4's together *
* *
* INPUT: *
* a - first operand *
* b - second operand *
* res - pointer to matrix to store the result in (must not point to a or b) *
* *
* OUTPUT: *
* *
* WARNINGS: *
* *
* HISTORY: *
* 11/13/99 gth : Created. *
*=============================================================================================*/
void Matrix4::Multiply(const Matrix4 &a,const Matrix4 &b,Matrix4 * res)
{
assert(res != &a);
assert(res != &b);
#define ROWCOL(i,j) a[i][0]*b[0][j] + a[i][1]*b[1][j] + a[i][2]*b[2][j] + a[i][3]*b[3][j]
(*res)[0][0] = ROWCOL(0,0);
(*res)[0][1] = ROWCOL(0,1);
(*res)[0][2] = ROWCOL(0,2);
(*res)[0][3] = ROWCOL(0,3);
(*res)[1][0] = ROWCOL(1,0);
(*res)[1][1] = ROWCOL(1,1);
(*res)[1][2] = ROWCOL(1,2);
(*res)[1][3] = ROWCOL(1,3);
(*res)[2][0] = ROWCOL(2,0);
(*res)[2][1] = ROWCOL(2,1);
(*res)[2][2] = ROWCOL(2,2);
(*res)[2][3] = ROWCOL(2,3);
(*res)[3][0] = ROWCOL(3,0);
(*res)[3][1] = ROWCOL(3,1);
(*res)[3][2] = ROWCOL(3,2);
(*res)[3][3] = ROWCOL(3,3);
#undef ROWCOL
}
/***********************************************************************************************
* Matrix4::Multiply -- Multiply a Matrix3D * Matrix4 *
* *
* INPUT: *
* *
* OUTPUT: *
* *
* WARNINGS: *
* *
* HISTORY: *
* 11/13/99 gth : Created. *
*=============================================================================================*/
void Matrix4::Multiply(const Matrix3D &a,const Matrix4 &b,Matrix4 * res)
{
assert(res != &b);
#define ROWCOL(i,j) a[i][0]*b[0][j] + a[i][1]*b[1][j] + a[i][2]*b[2][j] + a[i][3]*b[3][j]
(*res)[0][0] = ROWCOL(0,0);
(*res)[0][1] = ROWCOL(0,1);
(*res)[0][2] = ROWCOL(0,2);
(*res)[0][3] = ROWCOL(0,3);
(*res)[1][0] = ROWCOL(1,0);
(*res)[1][1] = ROWCOL(1,1);
(*res)[1][2] = ROWCOL(1,2);
(*res)[1][3] = ROWCOL(1,3);
(*res)[2][0] = ROWCOL(2,0);
(*res)[2][1] = ROWCOL(2,1);
(*res)[2][2] = ROWCOL(2,2);
(*res)[2][3] = ROWCOL(2,3);
(*res)[3][0] = b[3][0]; // last row of a is 0,0,0,1
(*res)[3][1] = b[3][1]; // this leaves the last row of b unchanged
(*res)[3][2] = b[3][2];
(*res)[3][3] = b[3][3];
#undef ROWCOL
}
/***********************************************************************************************
* Matrix4::Multiply -- Multiply a Matrix4 * Matrix3D *
* *
* INPUT: *
* *
* OUTPUT: *
* *
* WARNINGS: *
* *
* HISTORY: *
*=============================================================================================*/
void Matrix4::Multiply(const Matrix4 & a,const Matrix3D & b,Matrix4 * res)
{
assert(res != &a);
// ROWCOL multiplies a row of 'a' by one of the first three columns of 'b' (4th entry in b is zero)
// ROWCOL4 multiplies a row of 'a' by the fourth column of 'b' (4th entry in b is one)
#define ROWCOL(i,j) a[i][0]*b[0][j] + a[i][1]*b[1][j] + a[i][2]*b[2][j]
#define ROWCOL4(i,j) a[i][0]*b[0][j] + a[i][1]*b[1][j] + a[i][2]*b[2][j] + a[i][3]
(*res)[0][0] = ROWCOL(0,0);
(*res)[0][1] = ROWCOL(0,1);
(*res)[0][2] = ROWCOL(0,2);
(*res)[0][3] = ROWCOL4(0,3);
(*res)[1][0] = ROWCOL(1,0);
(*res)[1][1] = ROWCOL(1,1);
(*res)[1][2] = ROWCOL(1,2);
(*res)[1][3] = ROWCOL4(1,3);
(*res)[2][0] = ROWCOL(2,0);
(*res)[2][1] = ROWCOL(2,1);
(*res)[2][2] = ROWCOL(2,2);
(*res)[2][3] = ROWCOL4(2,3);
(*res)[3][0] = ROWCOL(3,0);
(*res)[3][1] = ROWCOL(3,1);
(*res)[3][2] = ROWCOL(3,2);
(*res)[3][3] = ROWCOL4(3,3);
#undef ROWCOL
#undef ROWCOL4
}