hello world

neo/idlib/math/Plane.cpp

@@ -0,0 +1,154 @@
+/*
+===========================================================================
+
+Doom 3 GPL Source Code
+Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company. 
+
+This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).  
+
+Doom 3 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.
+
+Doom 3 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 Doom 3 Source Code.  If not, see <http://www.gnu.org/licenses/>.
+
+In addition, the Doom 3 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 Doom 3 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 id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
+
+===========================================================================
+*/
+
+#include "../precompiled.h"
+#pragma hdrstop
+
+idPlane plane_origin( 0.0f, 0.0f, 0.0f, 0.0f );
+
+/*
+================
+idPlane::Type
+================
+*/
+int idPlane::Type( void ) const {
+	if ( Normal()[0] == 0.0f ) {
+		if ( Normal()[1] == 0.0f ) {
+			return Normal()[2] > 0.0f ? PLANETYPE_Z : PLANETYPE_NEGZ;
+		}
+		else if ( Normal()[2] == 0.0f ) {
+			return Normal()[1] > 0.0f ? PLANETYPE_Y : PLANETYPE_NEGY;
+		}
+		else {
+			return PLANETYPE_ZEROX;
+		}
+	}
+	else if ( Normal()[1] == 0.0f ) {
+		if ( Normal()[2] == 0.0f ) {
+			return Normal()[0] > 0.0f ? PLANETYPE_X : PLANETYPE_NEGX;
+		}
+		else {
+			return PLANETYPE_ZEROY;
+		}
+	}
+	else if ( Normal()[2] == 0.0f ) {
+		return PLANETYPE_ZEROZ;
+	}
+	else {
+		return PLANETYPE_NONAXIAL;
+	}
+}
+
+/*
+================
+idPlane::HeightFit
+================
+*/
+bool idPlane::HeightFit( const idVec3 *points, const int numPoints ) {
+	int i;
+	float sumXX = 0.0f, sumXY = 0.0f, sumXZ = 0.0f;
+	float sumYY = 0.0f, sumYZ = 0.0f;
+	idVec3 sum, average, dir;
+
+	if ( numPoints == 1 ) {
+		a = 0.0f;
+		b = 0.0f;
+		c = 1.0f;
+		d = -points[0].z;
+		return true;
+	}
+	if ( numPoints == 2 ) {
+		dir = points[1] - points[0];
+		Normal() = dir.Cross( idVec3( 0, 0, 1 ) ).Cross( dir );
+		Normalize();
+		d = -( Normal() * points[0] );
+		return true;
+	}
+
+	sum.Zero();
+	for ( i = 0; i < numPoints; i++) {
+		sum += points[i];
+	}
+	average = sum / numPoints;
+
+	for ( i = 0; i < numPoints; i++ ) {
+		dir = points[i] - average;
+		sumXX += dir.x * dir.x;
+		sumXY += dir.x * dir.y;
+		sumXZ += dir.x * dir.z;
+		sumYY += dir.y * dir.y;
+		sumYZ += dir.y * dir.z;
+	}
+
+	idMat2 m( sumXX, sumXY, sumXY, sumYY );
+	if ( !m.InverseSelf() ) {
+		return false;
+	}
+
+	a = - sumXZ * m[0][0] - sumYZ * m[0][1];
+	b = - sumXZ * m[1][0] - sumYZ * m[1][1];
+	c = 1.0f;
+	Normalize();
+	d = -( a * average.x + b * average.y + c * average.z );
+	return true;
+}
+
+/*
+================
+idPlane::PlaneIntersection
+================
+*/
+bool idPlane::PlaneIntersection( const idPlane &plane, idVec3 &start, idVec3 &dir ) const {
+	double n00, n01, n11, det, invDet, f0, f1;
+
+	n00 = Normal().LengthSqr();
+	n01 = Normal() * plane.Normal();
+	n11 = plane.Normal().LengthSqr();
+	det = n00 * n11 - n01 * n01;
+
+	if ( idMath::Fabs(det) < 1e-6f ) {
+		return false;
+	}
+
+	invDet = 1.0f / det;
+	f0 = ( n01 * plane.d - n11 * d ) * invDet;
+	f1 = ( n01 * d - n00 * plane.d ) * invDet;
+
+	dir = Normal().Cross( plane.Normal() );
+	start = f0 * Normal() + f1 * plane.Normal();
+	return true;
+}
+
+/*
+=============
+idPlane::ToString
+=============
+*/
+const char *idPlane::ToString( int precision ) const {
+	return idStr::FloatArrayToString( ToFloatPtr(), GetDimension(), precision );
+}