Games: Add Flood

Userland/Games/Flood/Board.cpp

@@ -0,0 +1,131 @@
+/*
+ * Copyright (c) 2022, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "Board.h"
+#include <AK/Random.h>
+#include <time.h>
+
+Board::Board(size_t rows, size_t columns)
+{
+    resize(rows, columns);
+}
+
+void Board::clear()
+{
+    for (size_t row = 0; row < m_rows; ++row) {
+        for (size_t column = 0; column < m_columns; ++column) {
+            set_cell(row, column, Color::Transparent);
+        }
+    }
+}
+
+bool Board::is_flooded() const
+{
+    auto first_cell_color = cell(0, 0).release_value();
+    for (size_t row = 0; row < rows(); ++row) {
+        for (size_t column = 0; column < columns(); ++column) {
+            if (first_cell_color == cell(row, column).release_value())
+                continue;
+            return false;
+        }
+    }
+    return true;
+}
+
+void Board::randomize()
+{
+    for (size_t row = 0; row < m_rows; ++row) {
+        for (size_t column = 0; column < m_columns; ++column) {
+            auto const& color = m_colors[get_random_uniform(m_colors.size())];
+            set_cell(row, column, color);
+        }
+    }
+    set_current_color(cell(0, 0).release_value());
+}
+
+void Board::resize(size_t rows, size_t columns)
+{
+    m_rows = rows;
+    m_columns = columns;
+
+    // Vector values get default-initialized, we don't need to set them explicitly.
+    m_cells.resize(rows);
+    for (size_t row = 0; row < rows; ++row)
+        m_cells[row].resize(columns);
+}
+
+void Board::set_cell(size_t row, size_t column, Color color)
+{
+    VERIFY(row < m_rows && column < m_columns);
+
+    m_cells[row][column] = color;
+}
+
+ErrorOr<Color> Board::cell(size_t row, size_t column) const
+{
+    if (row >= m_rows || column >= m_columns)
+        return Error::from_string_literal("No such cell.");
+
+    return m_cells[row][column];
+}
+
+void Board::set_current_color(Color new_color)
+{
+    m_previous_color = m_current_color;
+    m_current_color = new_color;
+}
+
+void Board::set_color_scheme(Vector<Color> colors)
+{
+    VERIFY(colors.size() == 8);
+    m_colors = move(colors);
+}
+
+void Board::reset()
+{
+    clear();
+    set_current_color(Color::Transparent);
+    m_previous_color = Color::Transparent;
+}
+
+// Adapted from Userland/PixelPaint/Tools/BucketTool.cpp::flood_fill.
+u32 Board::update_colors(bool only_calculate_flooded_area)
+{
+    Queue<Gfx::IntPoint> points_to_visit;
+
+    points_to_visit.enqueue({ 0, 0 });
+    set_cell(0, 0, get_current_color());
+
+    Vector<Vector<bool>> visited_board;
+    visited_board.resize(cells().size());
+    for (size_t row = 0; row < cells().size(); ++row)
+        visited_board[row].resize(cells()[row].size());
+    u32 painted = 1;
+
+    // This implements a non-recursive flood fill. This is a breadth-first search of paintable neighbors
+    // As we find neighbors that are paintable we update their pixel, add them to the queue, and mark them in the "visited_board".
+    while (!points_to_visit.is_empty()) {
+        auto current_point = points_to_visit.dequeue();
+        auto candidate_points = Array {
+            current_point.moved_left(1),
+            current_point.moved_right(1),
+            current_point.moved_up(1),
+            current_point.moved_down(1)
+        };
+        for (auto candidate_point : candidate_points) {
+            if (cell(candidate_point.y(), candidate_point.x()).is_error())
+                continue;
+            if (!visited_board[candidate_point.y()][candidate_point.x()] && cell(candidate_point.y(), candidate_point.x()).release_value() == (only_calculate_flooded_area ? get_current_color() : get_previous_color())) {
+                ++painted;
+                points_to_visit.enqueue(candidate_point);
+                visited_board[candidate_point.y()][candidate_point.x()] = true;
+                if (!only_calculate_flooded_area)
+                    set_cell(candidate_point.y(), candidate_point.x(), get_current_color());
+            }
+        }
+    }
+    return painted;
+}