paysages3d/src/basics/FractalNoise.cpp

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#include "FractalNoise.h"
FractalNoise::FractalNoise()
{
scaling = 1.0;
height = 1.0;
step_scaling = 2.0;
step_height = 0.5;
slope = 0.0;
ridge = 0.0;
}
void FractalNoise::setScaling(double scaling, double height)
{
this->scaling = scaling < 0.00000001 ? 0.0 : 1.0 / scaling;
this->height = scaling * height;
}
void FractalNoise::setStep(double scaling_factor, double height_factor)
{
this->step_scaling = scaling_factor < 0.00000001 ? 0.0 : 1.0 / scaling_factor;
this->step_height = scaling_factor * height_factor;
}
void FractalNoise::setSlope(double slope_factor)
{
this->slope = slope_factor;
}
void FractalNoise::setRidge(double ridge_factor)
{
this->ridge = ridge_factor;
}
void FractalNoise::setState(const NoiseState &state)
{
state.copy(&this->state);
}
double FractalNoise::get1d(double detail, double x) const
{
double current_scaling = scaling;
double current_height = height;
double result = 0.0;
int state_level_count = state.level_offsets.size();
int i = 0;
while (current_height >= detail)
{
const NoiseState::NoiseOffset &offset = state.level_offsets[i];
result += getBase1d(offset.x + x * current_scaling) * current_height;
current_scaling *= step_scaling;
current_height *= step_height;
i++;
if (i >= state_level_count)
{
i = 0;
}
}
return result;
}
double FractalNoise::get2d(double detail, double x, double y) const
{
double current_scaling = scaling;
double current_height = height;
double result = 0.0;
int state_level_count = state.level_offsets.size();
int i = 0;
while (current_height >= detail)
{
const NoiseState::NoiseOffset &offset = state.level_offsets[i];
result += getBase2d(offset.x + x * current_scaling, offset.y + y * current_scaling) * current_height;
current_scaling *= step_scaling;
current_height *= step_height;
i++;
if (i >= state_level_count)
{
i = 0;
}
}
return result;
}
double FractalNoise::get3d(double detail, double x, double y, double z) const
{
double current_scaling = scaling;
double current_height = height;
double result = 0.0;
int state_level_count = state.level_offsets.size();
int i = 0;
while (current_height >= detail)
{
const NoiseState::NoiseOffset &offset = state.level_offsets[i];
result += getBase3d(offset.x + x * current_scaling, offset.y + y * current_scaling, offset.z + z * current_scaling) * current_height;
current_scaling *= step_scaling;
current_height *= step_height;
i++;
if (i >= state_level_count)
{
i = 0;
}
}
return result;
}
double FractalNoise::getBase1d(double x) const
{
return getBase2d(x, 0.0);
}
double FractalNoise::getBase2d(double x, double y) const
{
return getBase3d(x, y, 0.0);
}