/*
|
* Java port of Bullet (c) 2008 Martin Dvorak <jezek2@advel.cz>
|
*
|
* Bullet Continuous Collision Detection and Physics Library
|
* Copyright (c) 2003-2008 Erwin Coumans http://www.bulletphysics.com/
|
*
|
* This software is provided 'as-is', without any express or implied warranty.
|
* In no event will the authors be held liable for any damages arising from
|
* the use of this software.
|
*
|
* Permission is granted to anyone to use this software for any purpose,
|
* including commercial applications, and to alter it and redistribute it
|
* freely, subject to the following restrictions:
|
*
|
* 1. The origin of this software must not be misrepresented; you must not
|
* claim that you wrote the original software. If you use this software
|
* in a product, an acknowledgment in the product documentation would be
|
* appreciated but is not required.
|
* 2. Altered source versions must be plainly marked as such, and must not be
|
* misrepresented as being the original software.
|
* 3. This notice may not be removed or altered from any source distribution.
|
*/
|
|
package com.bulletphysics.linearmath;
|
|
import com.bulletphysics.BulletGlobals;
|
|
/**
|
* Utility functions for scalars (floats).
|
*
|
* @author jezek2
|
*/
|
public class ScalarUtil {
|
|
public static float fsel(float a, float b, float c) {
|
return a >= 0 ? b : c;
|
}
|
|
public static boolean fuzzyZero(float x) {
|
return Math.abs(x) < BulletGlobals.FLT_EPSILON;
|
}
|
|
public static float atan2Fast(float y, float x) {
|
float coeff_1 = BulletGlobals.SIMD_PI / 4.0f;
|
float coeff_2 = 3.0f * coeff_1;
|
float abs_y = Math.abs(y);
|
float angle;
|
if (x >= 0.0f) {
|
float r = (x - abs_y) / (x + abs_y);
|
angle = coeff_1 - coeff_1 * r;
|
}
|
else {
|
float r = (x + abs_y) / (abs_y - x);
|
angle = coeff_2 - coeff_1 * r;
|
}
|
return (y < 0.0f) ? -angle : angle;
|
}
|
|
}
|
