SandGame/grass.js

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No EOL
1.3 KiB
JavaScript

import { grid, cols, rows } from './state.js';
import { config } from './config.js';
import { createCell } from './physics.js';
const dxs = [-1, 1, 0, 0];
const dys = [0, 0, -1, 1];
export function updateGrass(x, y, cell) {
// Spread along surface dirt/sand
if (Math.random() < (config.grass?.growChance || 0.03)) {
const dir = Math.floor(Math.random() * 4);
const nx = x + dxs[dir];
const ny = y + dys[dir];
if (nx >= 0 && nx < cols && ny >= 0 && ny < rows && grid[nx][ny]) {
const target = grid[nx][ny];
if (target.type === 'dirt' || target.type === 'sand') {
// Only colonize dirt if it has air/empty space nearby (surface grass)
const aboveDirt = ny - 1;
if (aboveDirt >= 0 && !grid[nx][aboveDirt]) {
grid[nx][ny] = createCell('grass');
return;
}
}
}
}
// Sprout blade feelers upwards into open air
if (Math.random() < (config.grass?.growChance || 0.03) * 0.4) {
const r = Math.random();
const dx = r < 0.3 ? -1 : (r > 0.7 ? 1 : 0);
const nx = x + dx;
const ny = y - 1;
if (nx >= 0 && nx < cols && ny >= 0 && !grid[nx][ny]) {
grid[nx][ny] = createCell('grass');
}
}
}