1*25c28e83SPiotr Jasiukajtis /* 2*25c28e83SPiotr Jasiukajtis * CDDL HEADER START 3*25c28e83SPiotr Jasiukajtis * 4*25c28e83SPiotr Jasiukajtis * The contents of this file are subject to the terms of the 5*25c28e83SPiotr Jasiukajtis * Common Development and Distribution License (the "License"). 6*25c28e83SPiotr Jasiukajtis * You may not use this file except in compliance with the License. 7*25c28e83SPiotr Jasiukajtis * 8*25c28e83SPiotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9*25c28e83SPiotr Jasiukajtis * or http://www.opensolaris.org/os/licensing. 10*25c28e83SPiotr Jasiukajtis * See the License for the specific language governing permissions 11*25c28e83SPiotr Jasiukajtis * and limitations under the License. 12*25c28e83SPiotr Jasiukajtis * 13*25c28e83SPiotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each 14*25c28e83SPiotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15*25c28e83SPiotr Jasiukajtis * If applicable, add the following below this CDDL HEADER, with the 16*25c28e83SPiotr Jasiukajtis * fields enclosed by brackets "[]" replaced with your own identifying 17*25c28e83SPiotr Jasiukajtis * information: Portions Copyright [yyyy] [name of copyright owner] 18*25c28e83SPiotr Jasiukajtis * 19*25c28e83SPiotr Jasiukajtis * CDDL HEADER END 20*25c28e83SPiotr Jasiukajtis */ 21*25c28e83SPiotr Jasiukajtis /* 22*25c28e83SPiotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 23*25c28e83SPiotr Jasiukajtis */ 24*25c28e83SPiotr Jasiukajtis /* 25*25c28e83SPiotr Jasiukajtis * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 26*25c28e83SPiotr Jasiukajtis * Use is subject to license terms. 27*25c28e83SPiotr Jasiukajtis */ 28*25c28e83SPiotr Jasiukajtis 29*25c28e83SPiotr Jasiukajtis #include "libm.h" 30*25c28e83SPiotr Jasiukajtis 31*25c28e83SPiotr Jasiukajtis static const double invpi = 0.3183098861837906715377675; 32*25c28e83SPiotr Jasiukajtis 33*25c28e83SPiotr Jasiukajtis float 34*25c28e83SPiotr Jasiukajtis atan2pif(float y, float x) { 35*25c28e83SPiotr Jasiukajtis int ix, iy, hx, hy; 36*25c28e83SPiotr Jasiukajtis 37*25c28e83SPiotr Jasiukajtis ix = *(int *)&x; 38*25c28e83SPiotr Jasiukajtis iy = *(int *)&y; 39*25c28e83SPiotr Jasiukajtis hx = ix & ~0x80000000; 40*25c28e83SPiotr Jasiukajtis hy = iy & ~0x80000000; 41*25c28e83SPiotr Jasiukajtis if (hx > 0x7f800000 || hy > 0x7f800000) /* x or y is nan */ 42*25c28e83SPiotr Jasiukajtis return (x * y); 43*25c28e83SPiotr Jasiukajtis if ((hx | hy) == 0) { 44*25c28e83SPiotr Jasiukajtis /* x and y are both zero */ 45*25c28e83SPiotr Jasiukajtis if (ix == 0) 46*25c28e83SPiotr Jasiukajtis return (y); 47*25c28e83SPiotr Jasiukajtis return ((iy == 0)? 1.0f : -1.0f); 48*25c28e83SPiotr Jasiukajtis } 49*25c28e83SPiotr Jasiukajtis return ((float)(invpi * atan2((double)y, (double)x))); 50*25c28e83SPiotr Jasiukajtis } 51