Imported existing code

indra/llmath/llplane.h

@@ -0,0 +1,73 @@
+/** 
+ * @file llplane.h
+ *
+ * $LicenseInfo:firstyear=2001&license=viewergpl$
+ * 
+ * Copyright (c) 2001-2009, Linden Research, Inc.
+ * 
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+
+#ifndef LL_LLPLANE_H
+#define LL_LLPLANE_H
+
+#include "v3math.h"
+#include "v4math.h"
+
+// A simple way to specify a plane is to give its normal,
+// and it's nearest approach to the origin.
+// 
+// Given the equation for a plane : A*x + B*y + C*z + D = 0
+// The plane normal = [A, B, C]
+// The closest approach = D / sqrt(A*A + B*B + C*C)
+
+class LLPlane : public LLVector4
+{
+public:
+	LLPlane() {}; // no default constructor
+	LLPlane(const LLVector3 &p0, F32 d) { setVec(p0, d); }
+	LLPlane(const LLVector3 &p0, const LLVector3 &n) { setVec(p0, n); }
+	void setVec(const LLVector3 &p0, F32 d) { LLVector4::setVec(p0[0], p0[1], p0[2], d); }
+	void setVec(const LLVector3 &p0, const LLVector3 &n)
+	{
+		F32 d = -(p0 * n);
+		setVec(n, d);
+	}
+	void setVec(const LLVector3 &p0, const LLVector3 &p1, const LLVector3 &p2)
+	{
+		LLVector3 u, v, w;
+		u = p1 - p0;
+		v = p2 - p0;
+		w = u % v;
+		w.normVec();
+		F32 d = -(w * p0);
+		setVec(w, d);
+	}
+	LLPlane& operator=(const LLVector4& v2) {  LLVector4::setVec(v2[0],v2[1],v2[2],v2[3]); return *this;}
+	F32 dist(const LLVector3 &v2) const { return mV[0]*v2[0] + mV[1]*v2[1] + mV[2]*v2[2] + mV[3]; }
+};
+
+
+
+#endif // LL_LLPLANE_H