VoxelSim/simulation.cpp

73 lines
2.3 KiB
C++

#include "simulation.h"
#include <cstring>
namespace simulation
{
int getCellOffset(
unsigned char x,
unsigned char y,
unsigned char z,
SimulationGrid* grid)
{
if (x < grid->x_max && y < grid->y_max && z < grid->z_max)
{
int offset = x + y * grid->x_max + z * (grid->y_max * grid->x_max);
return offset;
}
return -1;
}
void step(
double millisecondsSinceLastStep,
SimulationGrid* grid)
{
for (unsigned char x = 0; x < grid->x_max; x++)
{
for (unsigned char y = 0; y < grid->y_max; y++)
{
for (unsigned char z = 0; z < grid->z_max; z++)
{
int offset = getCellOffset(x, y, z, grid);
unsigned int material = grid->in[offset];
switch (material)
{
case WATER:
{
int downOffset = getCellOffset(x, y - 1, z, grid);
// Flow down if cell is empty
if (downOffset >= 0 && grid->out[downOffset] == 0)
{
grid->out[downOffset] = material;
grid->out[offset] = VACUUM;
} else
{
// Stay in the same location
grid->out[offset] = material;
}
break;
}
case MERCURY:
{
break;
}
default:
{
grid->out[offset] = material;
}
}
}
}
}
}
void prepareForNextStep(SimulationGrid* grid)
{
// Flip the buffers
unsigned int* inCells = grid->in;
grid->in = grid->out;
grid->out = inCells;
// Clear out buffer
size_t bufferSizeInBytes = sizeof(unsigned int) * grid->x_max * grid->y_max * grid->z_max;
std::memset(grid->out, VACUUM, bufferSizeInBytes);
}
}