sim.field.grid.Grid3D Maven / Gradle / Ivy
Show all versions of mason Show documentation
/*
Copyright 2006 by Sean Luke and George Mason University
Licensed under the Academic Free License version 3.0
See the file "LICENSE" for more information
*/
package sim.field.grid;
import sim.util.IntBag;
/**
Define basic neighborhood functions for 3D Grids. The basic interface defines a width and a height
(not all grids require a width and a height unless you're doing toroidal grids), and basic math for
toroidal computation.
Toroidal Computation
If you're using the Grid to define a toroidal (wrap-around) world, you can use the tx
and ty and tz methods to simplify the math for you. For example, to increment in the x direction,
including wrap-around, you can do: x = tx(x+1).
If you're sure that the values you'd pass into the toroidal functions would not wander off more than
a grid dimension in either direction (height, width, length), you can use the slightly faster toroidal functions
stx and sty and stz instead. For example, to increment in the x direction,
including wrap-around, you can do: x = stx(x+1). See the documentation on these functions for
when they're appropriate to use. Under most common situations, they're okay.
In HotSpot 1.4.1, stx, sty, and stz are inlined. In Hotspot 1.3.1, they are not (they contain if-statements).
While this interface defines various methods common to many grids, you should endeavor not to call these grids casted into this interface: it's slow. If you call the grids' methods directly by their class, their methods are almost certain to be inlined into your code, which is very fast.
*/
public interface Grid3D extends java.io.Serializable
{
/** Get the width */
public int getWidth();
/** Get the height */
public int getHeight();
/** Get the length */
public int getLength();
/** Toroidal x. The following definition:
final int length = this.length;
if (z >= 0) return (z % length);
final int length2 = (z % length) + length;
if (length2 < length) return length2;
return 0;
... produces the correct code and is 27 bytes, so it's likely to be inlined in Hotspot for 1.4.1.
*/
public int tx(final int x);
/** Toroidal y. The following definition:
final int length = this.length;
if (z >= 0) return (z % length);
final int length2 = (z % length) + length;
if (length2 < length) return length2;
return 0;
... produces the correct code and is 27 bytes, so it's likely to be inlined in Hotspot for 1.4.1.
*/
public int ty(final int y);
/** Toroidal z. The following definition:
final int length = this.length;
if (z >= 0) return (z % length);
final int length2 = (z % length) + length;
if (length2 < length) return length2;
return 0;
... produces the correct code and is 27 bytes, so it's likely to be inlined in Hotspot for 1.4.1.
*/
public int tz(final int z);
/** Simple [and fast] toroidal x. Use this if the values you'd pass in never stray
beyond (-width ... width * 2) not inclusive. It's a bit faster than the full
toroidal computation as it uses if statements rather than two modulos.
The following definition:
{ int width = this.width; if (x >= 0) { if (x < width) return x; return x - width; } return x + width; }
...produces the shortest code (24 bytes) and is inlined in Hotspot for 1.4.1. However
in most cases removing the int width = this.width; is likely to be a little faster if most
objects are usually within the toroidal region. */
public int stx(final int x);
/** Simple [and fast] toroidal y. Use this if the values you'd pass in never stray
beyond (-height ... height * 2) not inclusive. It's a bit faster than the full
toroidal computation as it uses if statements rather than two modulos.
The following definition:
{ int height = this.height; if (y >= 0) { if (y < height) return y ; return y - height; } return y + height; }
...produces the shortest code (24 bytes) and is inlined in Hotspot for 1.4.1. However
in most cases removing the int height = this.height; is likely to be a little faster if most
objects are usually within the toroidal region. */
public int sty(final int y);
/** Simple [and fast] toroidal z. Use this if the values you'd pass in never stray
beyond (-length ... length * 2) not inclusive. It's a bit faster than the full
toroidal computation as it uses if statements rather than two modulos.
The following definition:
{ int length = this.length; if (z >= 0) { if (z < length) return z ; return z - length; } return z + length; }
...produces the shortest code (24 bytes) and is inlined in Hotspot for 1.4.1. However
in most cases removing the int length = this.length; is likely to be a little faster if most
objects are usually within the toroidal region. */
public int stz(final int z);
/**
* Gets all neighbors of a location that satisfy max( abs(x-X) , abs(y-Y), abs(z-Z) ) <= dist. This region forms a
* cube 2*dist+1 cells across, centered at (X,Y,Z). If dist==1, this
* is equivalent to the twenty-six neighbors surrounding (X,Y,Z), plus (X,Y) itself.
* Places each x, y, and z value of these locations in the provided IntBags xPos, yPos, and zPos, clearing the bags first.
*/
public void getNeighborsMaxDistance( final int x, final int y, final int z, final int dist, final boolean toroidal, IntBag xPos, IntBag yPos, IntBag zPos );
/**
* Gets all neighbors of a location that satisfy abs(x-X) + abs(y-Y) + abs(z-Z) <= dist. This region
* forms an octohedron 2*dist+1 cells from point
* to opposite point inclusive, centered at (X,Y,Y). If dist==1 this is
* equivalent to the six neighbors above, below, left, and right, front, and behind (X,Y,Z)),
* plus (X,Y,Z) itself.
* Places each x, y, and z value of these locations in the provided IntBags xPos, yPos, and zPos, clearing the bags first.
*/
public void getNeighborsHamiltonianDistance( final int x, final int y, final int z, final int dist, final boolean toroidal, IntBag xPos, IntBag yPos, IntBag zPos );
}