157 lines
2.5 KiB
C++
157 lines
2.5 KiB
C++
/**
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\file G3D/units.h
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\maintainer Morgan McGuire, http://graphics.cs.williams.edu
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\created 2009-08-21
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\edited 2011-07-08
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*/
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#ifndef G3D_units_h
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#define G3D_units_h
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#include "G3D/platform.h"
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namespace G3D {
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/** Use <code>using namespace G3D::units;</code> to include all units
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into your program. The units system is specifically designed not to
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be general but to support commonly used units efficiently and
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clearly. See http://en.wikipedia.org/wiki/SI_prefix for interesting facts
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about SI/metric units and full definitions.*/
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namespace units {
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/** 1e-9 m */
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inline float nanometers() {
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return 1e-9f;
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}
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/** 1e-6 m */
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inline float micrometers() {
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return 1e-6f;
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}
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/** 0.001 m */
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inline float millimeters() {
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return 0.001f;
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}
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/** 0.01 m */
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inline float centimeters() {
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return 0.01f;
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}
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/** SI base unit of distance measure. */
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inline float meters() {
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return 1.0f;
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}
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/** 1000 m */
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inline float kilometers() {
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return 1000.0f;
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}
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/** 0.0254 m */
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inline float inches() {
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return 0.0254f;
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}
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/** 0.3048 m */
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inline float feet() {
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return 0.3048f;
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}
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/** 0.9144 m */
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inline float yards() {
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return 0.9144f;
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}
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/** 1609.344 m */
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inline float miles() {
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return 1609.344f;
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}
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/////////////////////////////////////////////////////////////
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/** SI base unit of angular measure. */
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inline float radians() {
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return 1.0f;
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}
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/** pi/180 */
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inline float degrees() {
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return 0.0174532925f;
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}
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//////////////////////////////////////////////////////////////
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/** 1e-9 s */
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inline float nanoseconds() {
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return 1e-9f;
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}
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/** 1e-3 s */
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inline float milliseconds() {
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return 1e-3f;
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}
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/** Base unit of time */
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inline float seconds() {
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return 1.0;
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}
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/** 60 s */
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inline float minutes() {
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return 60.0f;
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}
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/** 3600 s */
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inline float hours() {
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return 3600.0f;
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}
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/** 86400 s */
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inline float days() {
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return 86400.0f;
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}
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/** 31556926 s */
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inline float years() {
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return 31556926.0f;
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}
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///////////////////////////////////////////
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/** SI unit of mass */
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inline float kilograms() {
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return 1.0f;
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}
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///////////////////////////////////////////
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/** 1 kg m / s^2 */
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inline float newtons() {
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return 1.0f;
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}
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///////////////////////////////////////////
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/** SI unit of power: W = J/s*/
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inline float watts() {
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return 1.0;
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}
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/** SI unit of energy: J = N*m */
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inline float joules() {
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return 1.0;
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}
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/** Unit of solid angle measure. A sphere subtends 4 * pi sr. */
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inline float steradians() {
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return 1.0;
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}
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} // units
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} // G3D
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#endif
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