com.squidpony.basic.demo.BasicGame.java Source code

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Here is the source code for com.squidpony.basic.demo.BasicGame.java

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package com.squidpony.basic.demo;

import com.badlogic.gdx.ApplicationAdapter;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.InputAdapter;
import com.badlogic.gdx.InputMultiplexer;
import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.utils.viewport.ScreenViewport;
import squidpony.squidai.DijkstraMap;
import squidpony.squidgrid.gui.gdx.DefaultResources;
import squidpony.squidgrid.gui.gdx.SColor;
import squidpony.squidgrid.gui.gdx.SquidInput;
import squidpony.squidgrid.gui.gdx.SquidLayers;
import squidpony.squidgrid.gui.gdx.SquidMouse;
import squidpony.squidgrid.mapping.DungeonGenerator;
import squidpony.squidgrid.mapping.DungeonUtility;
import squidpony.squidmath.Coord;
import squidpony.squidmath.CoordPacker;
import squidpony.squidmath.LightRNG;
import squidpony.squidmath.RNG;

import java.util.ArrayList;

public class BasicGame extends ApplicationAdapter {
    SpriteBatch batch;

    private RNG rng;
    private SquidLayers display;
    private DungeonGenerator dungeonGen;
    private char[][] decoDungeon, bareDungeon, lineDungeon;
    private int[][] colorIndices, bgColorIndices;
    /** In number of cells */
    private int width;
    /** In number of cells */
    private int height;
    /** The pixel width of a cell */
    private int cellWidth;
    /** The pixel height of a cell */
    private int cellHeight;
    private SquidInput input;
    private Color bgColor;
    private Stage stage;
    private DijkstraMap playerToCursor;
    private Coord cursor, player;
    private ArrayList<Coord> toCursor;
    private ArrayList<Coord> awaitedMoves;
    private float secondsWithoutMoves;

    @Override
    public void create() {
        //These variables, corresponding to the screen's width and height in cells and a cell's width and height in
        //pixels, must match the size you specified in the launcher for input to behave.
        //This is one of the more common places a mistake can happen.
        //In our desktop launcher, we gave this arguments to the configuration:
        //   config.width = 80 * 12;
        //  config.height = 25 * 24;
        //Most games that do not use multiple Panels should probably use the same approach.
        width = 80;
        height = 25;
        cellWidth = 12;
        cellHeight = 24;
        // gotta have a random number generator. We seed a LightRNG with any long we want, then pass that to an RNG.
        rng = new RNG(new LightRNG(0xd00d));

        //Some classes in SquidLib need access to a batch to render certain things, so it's a good idea to have one.
        batch = new SpriteBatch();
        //Here we make sure our Stage, which holds any text-based grids we make, uses our Batch.
        stage = new Stage(new ScreenViewport(), batch);
        // the font will try to load Inconsolata-LGC as a bitmap font from resources.
        // this font is covered under the SIL Open Font License (fully free), so there's no reason it can't be used.
        display = new SquidLayers(width, height, cellWidth, cellHeight, DefaultResources.smoothNameLarge);
        display.setAnimationDuration(0.03f);

        //These need to have their positions set before adding any entities if there is an offset involved.
        //There is no offset used here, but it's still a good practice here to set positions early on.
        display.setPosition(0, 0);

        //This uses the seeded RNG we made earlier to build a procedural dungeon using a method that takes rectangular
        //sections of pre-drawn dungeon and drops them into place in a tiling pattern. It makes good "ruined" dungeons.
        dungeonGen = new DungeonGenerator(width, height, rng);
        //uncomment this next line to randomly add water to the dungeon in pools.
        //dungeonGen.addWater(15);
        //decoDungeon is given the dungeon with any decorations we specified. (Here, we didn't, unless you chose to add
        //water to the dungeon. In that case, decoDungeon will have different contents than bareDungeon, next.)
        decoDungeon = dungeonGen.generate();
        //getBareDungeon provides the simplest representation of the generated dungeon -- '#' for walls, '.' for floors.
        bareDungeon = dungeonGen.getBareDungeon();
        //When we draw, we may want to use a nicer representation of walls. DungeonUtility has lots of useful methods
        //for modifying char[][] dungeon grids, and this one takes each '#' and replaces it with a box-drawing character.
        lineDungeon = DungeonUtility.hashesToLines(decoDungeon);
        // it's more efficient to get random floors from a packed set containing only (compressed) floor positions.
        short[] placement = CoordPacker.pack(bareDungeon, '.');
        //Coord is the type we use as a general 2D point, usually in a dungeon.
        //Because we know dungeons won't be incredibly huge, Coord performs best for x and y values less than 256.
        cursor = Coord.get(-1, -1);
        //player is, here, just a Coord that stores his position. In a real game, you would probably have a class for
        //creatures, and possibly a subclass for the player.
        player = dungeonGen.utility.randomCell(placement);
        //This is used to allow clicks or taps to take the player to the desired area.
        toCursor = new ArrayList<Coord>(100);
        awaitedMoves = new ArrayList<Coord>(100);
        //DijkstraMap is the pathfinding swiss-army knife we use here to find a path to the latest cursor position.
        playerToCursor = new DijkstraMap(decoDungeon, DijkstraMap.Measurement.MANHATTAN);
        bgColor = SColor.DARK_SLATE_GRAY;
        colorIndices = DungeonUtility.generatePaletteIndices(decoDungeon);
        bgColorIndices = DungeonUtility.generateBGPaletteIndices(decoDungeon);
        // this is a big one.
        // SquidInput can be constructed with a KeyHandler (which just processes specific keypresses), a SquidMouse
        // (which is given an InputProcessor implementation and can handle multiple kinds of mouse move), or both.
        // keyHandler is meant to be able to handle complex, modified key input, typically for games that distinguish
        // between, say, 'q' and 'Q' for 'quaff' and 'Quip' or whatever obtuse combination you choose. The
        // implementation here handles hjkl keys (also called vi-keys), numpad, arrow keys, and wasd for 4-way movement.
        // Shifted letter keys produce capitalized chars when passed to KeyHandler.handle(), but we don't care about
        // that so we just use two case statements with the same body, i.e. one for 'A' and one for 'a'.
        // You can also set up a series of future moves by clicking within FOV range, using mouseMoved to determine the
        // path to the mouse position with a DijkstraMap (called playerToCursor), and using touchUp to actually trigger
        // the event when someone clicks.
        input = new SquidInput(new SquidInput.KeyHandler() {
            @Override
            public void handle(char key, boolean alt, boolean ctrl, boolean shift) {
                switch (key) {
                case SquidInput.UP_ARROW:
                case 'k':
                case 'w':
                case 'K':
                case 'W': {
                    //-1 is up on the screen
                    move(0, -1);
                    break;
                }
                case SquidInput.DOWN_ARROW:
                case 'j':
                case 's':
                case 'J':
                case 'S': {
                    //+1 is down on the screen
                    move(0, 1);
                    break;
                }
                case SquidInput.LEFT_ARROW:
                case 'h':
                case 'a':
                case 'H':
                case 'A': {
                    move(-1, 0);
                    break;
                }
                case SquidInput.RIGHT_ARROW:
                case 'l':
                case 'd':
                case 'L':
                case 'D': {
                    move(1, 0);
                    break;
                }
                case 'Q':
                case 'q':
                case SquidInput.ESCAPE: {
                    Gdx.app.exit();
                    break;
                }
                }
            }
        },
                //The second parameter passed to a SquidInput can be a SquidMouse, which takes mouse or touchscreen
                //input and converts it to grid coordinates (here, a cell is 12 wide and 24 tall, so clicking at the
                // pixel position 15,51 will pass screenX as 1 (since if you divide 15 by 12 and round down you get 1),
                // and screenY as 2 (since 51 divided by 24 rounded down is 2)).
                new SquidMouse(cellWidth, cellHeight, width, height, 0, 0, new InputAdapter() {

                    // if the user clicks and there are no awaitedMoves queued up, generate toCursor if it
                    // hasn't been generated already by mouseMoved, then copy it over to awaitedMoves.
                    @Override
                    public boolean touchUp(int screenX, int screenY, int pointer, int button) {
                        if (awaitedMoves.isEmpty()) {
                            if (toCursor.isEmpty()) {
                                cursor = Coord.get(screenX, screenY);
                                //This uses DijkstraMap.findPath to get a possibly long path from the current player position
                                //to the position the user clicked on.
                                toCursor = playerToCursor.findPath(100, null, null, player, cursor);
                            }
                            awaitedMoves = new ArrayList<>(toCursor);
                        }
                        return false;
                    }

                    @Override
                    public boolean touchDragged(int screenX, int screenY, int pointer) {
                        return mouseMoved(screenX, screenY);
                    }

                    // causes the path to the mouse position to become highlighted (toCursor contains a list of points that
                    // receive highlighting). Uses DijkstraMap.findPath() to find the path, which is surprisingly fast.
                    @Override
                    public boolean mouseMoved(int screenX, int screenY) {
                        if (!awaitedMoves.isEmpty())
                            return false;
                        if (cursor.x == screenX && cursor.y == screenY) {
                            return false;
                        }
                        cursor = Coord.get(screenX, screenY);
                        toCursor = playerToCursor.findPath(100, null, null, player, cursor);
                        return false;
                    }
                }));
        //Setting the InputProcessor is ABSOLUTELY NEEDED TO HANDLE INPUT
        Gdx.input.setInputProcessor(new InputMultiplexer(stage, input));
        //You might be able to get by with the next line instead of the above line, but the former is preferred.
        //Gdx.input.setInputProcessor(input);
        // and then add display, our one visual component, to the list of things that act in Stage.
        stage.addActor(display);

    }

    /**
     * Move the player if he isn't bumping into a wall or trying to go off the map somehow.
     * In a fully-fledged game, this would not be organized like this, but this is a one-file demo.
     * @param xmod
     * @param ymod
     */
    private void move(int xmod, int ymod) {
        int newX = player.x + xmod, newY = player.y + ymod;
        if (newX >= 0 && newY >= 0 && newX < width && newY < height && bareDungeon[newX][newY] != '#') {
            player = player.translate(xmod, ymod);
        }
    }

    /**
     * Draws the map, applies any highlighting for the path to the cursor, and then draws the player.
     */
    public void putMap() {
        for (int i = 0; i < width; i++) {
            for (int j = 0; j < height; j++) {
                display.put(i, j, lineDungeon[i][j], colorIndices[i][j], bgColorIndices[i][j], 40);
            }
        }
        for (Coord pt : toCursor) {
            // use a brighter light to trace the path to the cursor, from 170 max lightness to 0 min.
            display.highlight(pt.x, pt.y, 100);
        }
        //places the player as an '@' at his position in orange (6 is an index into SColor.LIMITED_PALETTE).
        display.put(player.x, player.y, '@', 6);
    }

    @Override
    public void render() {
        // standard clear the background routine for libGDX
        Gdx.gl.glClearColor(bgColor.r / 255.0f, bgColor.g / 255.0f, bgColor.b / 255.0f, 1.0f);
        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);

        // need to display the map every frame, since we clear the screen to avoid artifacts.
        putMap();
        // if the user clicked, we have a list of moves to perform.
        if (!awaitedMoves.isEmpty()) {
            // this doesn't check for input, but instead processes and removes Points from awaitedMoves.
            secondsWithoutMoves += Gdx.graphics.getDeltaTime();
            if (secondsWithoutMoves >= 0.1) {
                secondsWithoutMoves = 0;
                Coord m = awaitedMoves.remove(0);
                toCursor.remove(0);
                move(m.x - player.x, m.y - player.y);
            }
        }
        // if we are waiting for the player's input and get input, process it.
        else if (input.hasNext()) {
            input.next();
        }

        // stage has its own batch and must be explicitly told to draw(). this also causes it to act().
        stage.draw();
    }

    @Override
    public void resize(int width, int height) {
        super.resize(width, height);
        //very important to have the mouse behave correctly if the user fullscreens or resizes the game!
        input.getMouse().reinitialize((float) width / this.width, height / this.height);
    }
}