historical/toontown-classic.git/panda/include/perlinNoise3.I

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/**
* PANDA 3D SOFTWARE
* Copyright (c) Carnegie Mellon University. All rights reserved.
*
* All use of this software is subject to the terms of the revised BSD
* license. You should have received a copy of this license along
* with this source code in a file named "LICENSE."
*
* @file perlinNoise3.I
* @author drose
* @date 2005-10-05
*/
/**
* Randomizes the tables to make a unique noise function. Uses a default
* scale (noise frequency), table size, and seed.
*/
INLINE PerlinNoise3::
PerlinNoise3() :
PerlinNoise(256, 0)
{
init_unscaled_xform();
_input_xform = _unscaled_xform;
}
/**
* Randomizes the tables to make a unique noise function.
*
* If seed is nonzero, it is used to define the tables; if it is zero a random
* seed is generated.
*/
INLINE PerlinNoise3::
PerlinNoise3(double sx, double sy, double sz,
int table_size, unsigned long seed) :
PerlinNoise(table_size, seed)
{
init_unscaled_xform();
set_scale(sx, sy, sz);
}
/**
* Makes an exact copy of the existing PerlinNoise object, including its
* random seed.
*/
INLINE PerlinNoise3::
PerlinNoise3(const PerlinNoise3 &copy) :
PerlinNoise(copy),
_unscaled_xform(copy._unscaled_xform),
_input_xform(copy._input_xform)
{
}
/**
* Makes an exact copy of the existing PerlinNoise object, including its
* random seed.
*/
INLINE void PerlinNoise3::
operator = (const PerlinNoise3 &copy) {
PerlinNoise::operator = (copy);
_unscaled_xform = copy._unscaled_xform;
_input_xform = copy._input_xform;
}
/**
* Changes the scale (frequency) of the noise.
*/
INLINE void PerlinNoise3::
set_scale(double scale) {
set_scale(scale, scale, scale);
}
/**
* Changes the scale (frequency) of the noise.
*/
INLINE void PerlinNoise3::
set_scale(double x, double y, double z) {
set_scale(LVecBase3d(x, y, z));
}
/**
* Changes the scale (frequency) of the noise.
*/
INLINE void PerlinNoise3::
set_scale(const LVecBase3f &value) {
set_scale(value[0], value[1], value[2]);
}
/**
* Changes the scale (frequency) of the noise.
*/
INLINE void PerlinNoise3::
set_scale(const LVecBase3d &value) {
_input_xform = LMatrix4d::scale_mat(1.0f / value[0], 1.0f / value[1], 1.0f / value[2]) * _unscaled_xform;
}
/**
* Returns the noise function of the three inputs.
*/
INLINE double PerlinNoise3::
noise(double x, double y, double z) const {
return noise(LVecBase3d(x, y, z));
}
/**
* Returns the noise function of the three inputs.
*/
INLINE float PerlinNoise3::
noise(const LVecBase3f &value) const {
return (float)noise(value[0], value[1], value[2]);
}
/**
* Returns the noise function of the three inputs.
*/
INLINE double PerlinNoise3::
operator ()(double x, double y, double z) const {
return noise(x, y, z);
}
/**
* Returns the noise function of the three inputs.
*/
INLINE float PerlinNoise3::
operator ()(const LVecBase3f &value) const {
return noise(value);
}
/**
* Returns the noise function of the three inputs.
*/
INLINE double PerlinNoise3::
operator ()(const LVecBase3d &value) const {
return noise(value);
}
/**
* Returns the dot product of a random gradient vector (determined by the hash
* code) with the indicated offset vector.
*/
INLINE double PerlinNoise3::
grad(int hash, double x, double y, double z) {
// Convert low 4 bits of hash code into 12 gradient directions.
/*
This is Perlin's reference code, but the switch statement below is
slightly faster and produces exactly the same results.
int h = hash & 15;
double u = (h < 8) ? x : y;
double v = (h < 4) ? y : ((h == 12 || h == 14) ? x : z);
return ((h & 1) ? -u : u) + ((h & 2) ? -v : v);
*/
switch (hash & 15) {
case 0: return x + y;
case 1: return -x + y;
case 2: return x - y;
case 3: return -x - y;
case 4: return x + z;
case 5: return -x + z;
case 6: return x - z;
case 7: return -x - z;
case 8: return y + z;
case 9: return -y + z;
case 10: return y - z;
case 11: return -y - z;
case 12: return x + y;
case 13: return -y + z;
case 14: return -x + y;
case 15: return -y - z;
}
nassertr(false, 0);
return 0;
}