RosettaCodeData/Task/Forest-fire/Ceylon/forest-fire.ceylon

125 lines
3.4 KiB
Ceylon

import ceylon.random { DefaultRandom }
abstract class Cell() of tree | dirt | burning {}
object tree extends Cell() { string => "A"; }
object dirt extends Cell() { string => " "; }
object burning extends Cell() { string => "#"; }
class Forest(Integer width, Integer height, Float f, Float p) {
value random = DefaultRandom();
function chance(Float probability) => random.nextFloat() < probability;
value sparked => chance(f);
value sprouted => chance(p);
alias Point => Integer[2];
interface Row => {Cell*};
object doubleBufferedGrid satisfies
Correspondence<Point, Cell> &
KeyedCorrespondenceMutator<Point, Cell> {
value grids = [
Array {
for (j in 0:height)
Array {
for (i in 0:width)
chance(0.5) then tree else dirt
}
},
Array {
for (j in 0:height)
Array.ofSize(width, dirt)
}
];
variable value showFirst = true;
value currentState => showFirst then grids.first else grids.last;
value nextState => showFirst then grids.last else grids.first;
shared void swapStates() => showFirst = !showFirst;
shared {Row*} rows => currentState;
shared actual Boolean defines(Point key) =>
let (x = key[0], y = key[1])
0 <= x < width && 0 <= y < height;
shared actual Cell? get(Point key) =>
let (x = key[0], y = key[1])
currentState.get(y)?.get(x);
shared actual void put(Point key, Cell cell) {
value [x, y] = key;
nextState.get(y)?.set(x, cell);
}
}
variable value evolutions = 0;
shared Integer generation => evolutions + 1;
shared void evolve() {
evolutions++;
function firesNearby(Integer x, Integer y) => {
for (j in y - 1 : 3)
for (i in x - 1 : 3)
doubleBufferedGrid[[i, j]]
}.coalesced.any(burning.equals);
for(j->row in doubleBufferedGrid.rows.indexed) {
for(i->cell in row.indexed) {
switch (cell)
case (burning) {
doubleBufferedGrid[[i, j]] = dirt;
}
case (dirt) {
doubleBufferedGrid[[i, j]] = sprouted then tree else dirt;
}
case (tree) {
doubleBufferedGrid[[i, j]] =
firesNearby(i, j) || sparked
then burning else tree;
}
}
}
doubleBufferedGrid.swapStates();
}
shared void display() {
void drawLine() => print("-".repeat(width + 2));
drawLine();
for (row in doubleBufferedGrid.rows) {
process.write("|");
for (cell in row) {
process.write(cell.string);
}
print("|");
}
drawLine();
}
}
shared void run() {
value forest = Forest(78, 38, 0.02, 0.03);
while (true) {
forest.display();
print("Generation ``forest.generation``");
print("Press enter for next generation or q and then enter to quit");
value input = process.readLine();
if (exists input, input.trimmed.lowercased == "q") {
return;
}
forest.evolve();
}
}