Java tutorial
package com.github.squidpony; 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.StretchViewport; import squidpony.FakeLanguageGen; import squidpony.squidai.DijkstraMap; import squidpony.squidgrid.gui.gdx.*; import squidpony.squidgrid.mapping.DungeonGenerator; import squidpony.squidgrid.mapping.DungeonUtility; import squidpony.squidmath.Coord; import squidpony.squidmath.GreasedRegion; import squidpony.squidmath.RNG; import java.util.ArrayList; import java.util.Arrays; /** * The main class of the game, constructed once in each of the platform-specific Launcher classes. Doesn't use any * platform-specific code. */ // If this is an example project in gdx-setup, then squidlib-util and the squidlib (the display module) are always // dependencies. If you didn't change those dependencies, this class should run out of the box. // // This class is useful as a starting point, since it has dungeon generation and some of the trickier parts of input // handling (using the mouse to get a path for the player) already filled in. You can remove any imports or usages of // classes that you don't need. // A main game class that uses LibGDX to display, which is the default for SquidLib, needs to extend ApplicationAdapter // or something related, like Game. Game adds features that SquidLib doesn't currently use, so ApplicationAdapter is // perfectly fine for these uses. public class SquidBasicDemo 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 gridWidth; /** In number of cells */ private int gridHeight; /** 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; private String[] lang; private int langIndex = 0; @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 these arguments to the configuration: // config.width = 80 * 8; // config.height = 40 * 18; //Here, config.height refers to the total number of rows to be displayed on the screen. //We're displaying 32 rows of dungeon, then 8 more rows of text generation to show some tricks with language. //gridHeight is 32 because that variable will be used for generating the dungeon and handling movement within //the upper 32 rows. Anything that refers to the full height, which happens rarely and usually for things like //screen resizes, just uses gridHeight + 8. Next to it is gridWidth, which is 80 because we want 80 grid spaces //across the whole screen. cellWidth and cellHeight are 8 and 18, and match the multipliers for config.width and //config.height, but in this case don't strictly need to because we soon use a "Stretchable" font. While //gridWidth and gridHeight are measured in spaces on the grid, cellWidth and cellHeight are the pixel dimensions //of an individual cell. The font will look more crisp if the cell dimensions match the config multipliers //exactly, and the stretchable fonts (technically, distance field fonts) can resize to non-square sizes and //still retain most of that crispness. gridWidth = 80; gridHeight = 24; cellWidth = 14; cellHeight = 21; // gotta have a random number generator. We can seed an RNG with any long we want, or even a String. rng = new RNG("SquidLib!"); //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 StretchViewport(gridWidth * cellWidth, (gridHeight + 8) * cellHeight), batch); // the font will try to load CM-Custom as an embedded bitmap font with a distance field effect. // 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(gridWidth, gridHeight + 8, cellWidth, cellHeight, DefaultResources.getStretchableTypewriterFont()); // a bit of a hack to increase the text height slightly without changing the size of the cells they're in. // this causes a tiny bit of overlap between cells, which gets rid of an annoying gap between vertical lines. // if you use '#' for walls instead of box drawing chars, you don't need this. display.setTextSize(cellWidth, cellHeight + 1); // this makes animations very fast, which is good for multi-cell movement but bad for attack animations. 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(gridWidth, gridHeight, 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); //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, but // by default it can also handle some negative x and y values (-3 is the lowest it can efficiently store). You // can call Coord.expandPool() or Coord.expandPoolTo() if you need larger maps to be just as fast. cursor = Coord.get(-1, -1); // here, we need to get a random floor cell to place the player upon, without the possibility of putting him // inside a wall. There are a few ways to do this in SquidLib. The most straightforward way is to randomly // choose x and y positions until a floor is found, but particularly on dungeons with few floor cells, this can // have serious problems -- if it takes too long to find a floor cell, either it needs to be able to figure out // that random choice isn't working and instead choose the first it finds in simple iteration, or potentially // keep trying forever on an all-wall map. There are better ways! These involve using a kind of specific storage // for points or regions, getting that to store only floors, and finding a random cell from that collection of // floors. The two kinds of such storage used commonly in SquidLib are the "packed data" as short[] produced by // CoordPacker (which use very little memory, but can be slow, and are treated as unchanging by CoordPacker so // any change makes a new array), and GreasedRegion objects (which use slightly more memory, tend to be faster // on almost all operations compared to the same operations with CoordPacker, and default to changing the // GreasedRegion object when you call a method on it instead of making a new one). Even though CoordPacker // sometimes has better documentation, GreasedRegion is generally a better choice; it was added to address // shortcomings in CoordPacker, particularly for speed, and the worst-case scenarios for data in CoordPacker are // no problem whatsoever for GreasedRegion. CoordPacker is called that because it compresses the information // for nearby Coords into a smaller amount of memory. GreasedRegion is called that because it encodes regions, // but is "greasy" both in the fatty-food sense of using more space, and in the "greased lightning" sense of // being especially fast. Both of them can be seen as storing regions of points in 2D space as "on" and "off." // Here we fill a GreasedRegion so it stores the cells that contain a floor, the '.' char, as "on." GreasedRegion placement = new GreasedRegion(bareDungeon, '.'); //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. The singleRandom() method on GreasedRegion finds one Coord // in that region that is "on," or -1,-1 if there are no such cells. It takes an RNG object as a parameter, and // if you gave a seed to the RNG constructor, then the cell this chooses will be reliable for testing. If you // don't seed the RNG, any valid cell should be possible. player = placement.singleRandom(rng); //This is used to allow clicks or taps to take the player to the desired area. toCursor = new ArrayList<Coord>(200); //When a path is confirmed by clicking, we draw from this List to find which cell is next to move into. awaitedMoves = new ArrayList<Coord>(200); //DijkstraMap is the pathfinding swiss-army knife we use here to find a path to the latest cursor position. //DijkstraMap.Measurement is an enum that determines the possibility or preference to enter diagonals. Here, the // MANHATTAN value is used, which means 4-way movement only, no diagonals possible. Alternatives are CHEBYSHEV, // which allows 8 directions of movement at the same cost for all directions, and EUCLIDEAN, which allows 8 // directions, but will prefer orthogonal moves unless diagonal ones are clearly closer "as the crow flies." playerToCursor = new DijkstraMap(decoDungeon, DijkstraMap.Measurement.MANHATTAN); //These next two lines mark the player as something we want paths to go to or from, and get the distances to the // player from all walkable cells in the dungeon. playerToCursor.setGoal(player); playerToCursor.scan(null); //The next three lines set the background color for anything we don't draw on, but also create 2D arrays of the //same size as decoDungeon that store simple indexes into a common list of colors, using the colors that looks // up as the colors for the cell with the same x and y. bgColor = SColor.DARK_SLATE_GRAY; colorIndices = DungeonUtility.generatePaletteIndices(decoDungeon); bgColorIndices = DungeonUtility.generateBGPaletteIndices(decoDungeon); // this creates an array of sentences, where each imitates a different sort of language or mix of languages. // this serves to demonstrate the large amount of glyphs SquidLib supports. // there's no need to put much effort into understanding this section yet, and many games won't use the language // generation code at all. If you want to know what this does, the parameters are: // minimum words in a sentence, maximum words in a sentence, "mid" punctuation that can be after a word (like a // comma), "end" punctuation that can be at the end of a sentence, frequency of "mid" punctuation (the chance in // 1.0 that a word will have something like a comma appended after it), and the limit on how many chars to use. lang = new String[] { FakeLanguageGen.ENGLISH.sentence(5, 10, new String[] { ",", ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.17, gridWidth - 4), FakeLanguageGen.GREEK_AUTHENTIC.sentence(5, 11, new String[] { ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.2, gridWidth - 4), FakeLanguageGen.GREEK_ROMANIZED.sentence(5, 11, new String[] { ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.2, gridWidth - 4), FakeLanguageGen.LOVECRAFT.sentence(3, 9, new String[] { ",", ",", ";" }, new String[] { ".", ".", "!", "!", "?", "...", "..." }, 0.15, gridWidth - 4), FakeLanguageGen.FRENCH.sentence(4, 12, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.17, gridWidth - 4), FakeLanguageGen.RUSSIAN_AUTHENTIC.sentence(6, 13, new String[] { ",", ",", ",", ",", ";", " -" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.25, gridWidth - 4), FakeLanguageGen.RUSSIAN_ROMANIZED.sentence(6, 13, new String[] { ",", ",", ",", ",", ";", " -" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.25, gridWidth - 4), FakeLanguageGen.JAPANESE_ROMANIZED.sentence(5, 13, new String[] { ",", ",", ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "...", "..." }, 0.12, gridWidth - 4), FakeLanguageGen.SWAHILI.sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.SOMALI.sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.HINDI_ROMANIZED.sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.ARABIC_ROMANIZED.sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.NORSE.addModifiers(FakeLanguageGen.Modifier.SIMPLIFY_NORSE).sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.INUKTITUT.sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.NAHUATL.sentence(4, 9, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?" }, 0.12, gridWidth - 4), FakeLanguageGen.FANTASY_NAME.sentence(4, 8, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.22, gridWidth - 4), FakeLanguageGen.FANCY_FANTASY_NAME.sentence(4, 8, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.22, gridWidth - 4), FakeLanguageGen.GOBLIN.sentence(4, 8, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "?", "...", "..." }, 0.12, gridWidth - 4), FakeLanguageGen.ELF.sentence(4, 8, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "?", "..." }, 0.22, gridWidth - 4), FakeLanguageGen.DEMONIC.sentence(4, 8, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "!", "!", "..." }, 0.1, gridWidth - 4), FakeLanguageGen.INFERNAL.sentence(4, 8, new String[] { ",", ",", ",", ";", ";" }, new String[] { ".", ".", ".", "?", "?", "..." }, 0.22, gridWidth - 4), FakeLanguageGen.FRENCH.mix(FakeLanguageGen.JAPANESE_ROMANIZED, 0.65).sentence(5, 9, new String[] { ",", ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "?", "..." }, 0.14, gridWidth - 4), FakeLanguageGen.ENGLISH.addAccents(0.5, 0.15).sentence(5, 10, new String[] { ",", ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.17, gridWidth - 4), // mixAll is useful when mixing many languages; it takes alternating languages and weights for // the preceding language, and doesn't care what order the pairs are given in (the mix method // does care, which can be confusing when more than two languages are mixed). FakeLanguageGen.mixAll(FakeLanguageGen.SWAHILI, 1.0, FakeLanguageGen.JAPANESE_ROMANIZED, 1.0, FakeLanguageGen.FRENCH, 1.0, FakeLanguageGen.RUSSIAN_ROMANIZED, 1.0, FakeLanguageGen.GREEK_ROMANIZED, 1.0, FakeLanguageGen.ENGLISH, 1.2, FakeLanguageGen.ELF, 1.0, FakeLanguageGen.LOVECRAFT, 0.75).sentence(5, 10, new String[] { ",", ",", ",", ";" }, new String[] { ".", ".", ".", "!", "?", "..." }, 0.2, gridWidth - 4), }; // 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, gridWidth, gridHeight, 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.findPathPreScannned() to get a path as a List of Coord from the current // player position to the position the user clicked on. The "PreScanned" part is an optimization // that's special to DijkstraMap; because the whole map has already been fully analyzed by the // DijkstraMap.scan() method at the start of the program, and re-calculated whenever the player // moves, we only need to do a fraction of the work to find the best path with that info. toCursor = playerToCursor.findPathPreScanned(cursor); } awaitedMoves.addAll(toCursor); } return true; } @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 Coords that // receive highlighting). Uses DijkstraMap.findPathPreScanned() to find the path, which is rather 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); //This uses DijkstraMap.findPathPreScannned() to get a path as a List of Coord from the current // player position to the position the user clicked on. The "PreScanned" part is an optimization // that's special to DijkstraMap; because the whole map has already been fully analyzed by the // DijkstraMap.scan() method at the start of the program, and re-calculated whenever the player // moves, we only need to do a fraction of the work to find the best path with that info. toCursor = playerToCursor.findPathPreScanned(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 < gridWidth && newY < gridHeight && bareDungeon[newX][newY] != '#') { // changing the player Coord is all we need to do here, because we re-calculate the distances to the player // from all other cells only when we need to, that is, when the movement is finished (see render() ). player = player.translate(xmod, ymod); } // loops through the text snippets displayed whenever the player moves langIndex = (langIndex + 1) % lang.length; } /** * 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 < gridWidth; i++) { for (int j = 0; j < gridHeight; 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); //this helps compatibility with the HTML target, which doesn't support String.format() char[] spaceArray = new char[gridWidth]; Arrays.fill(spaceArray, ' '); String spaces = String.valueOf(spaceArray); for (int i = 0; i < 6; i++) { display.putString(0, gridHeight + i + 1, spaces, 0, 1); display.putString(2, gridHeight + i + 1, lang[(langIndex + i) % lang.length], 0, 1); } } @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 Coords 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); } // this only happens if we just removed the last Coord from awaitedMoves, and it's only then that we need to // re-calculate the distances from all cells to the player. We don't need to calculate this information on // each part of a many-cell move (just the end), nor do we need to calculate it whenever the mouse moves. if (awaitedMoves.isEmpty()) { // the next two lines remove any lingering data needed for earlier paths playerToCursor.clearGoals(); playerToCursor.resetMap(); // the next line marks the player as a "goal" cell, which seems counter-intuitive, but it works because all // cells will try to find the distance between themselves and the nearest goal, and once this is found, the // distances don't change as long as the goals don't change. Since the mouse will move and new paths will be // found, but the player doesn't move until a cell is clicked, the "goal" is the non-changing cell, so the // player's position, and the "target" of a pathfinding method like DijkstraMap.findPathPreScanned() is the // currently-moused-over cell, which we only need to set where the mouse is being handled. playerToCursor.setGoal(player); playerToCursor.scan(null); } } // 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(). stage.draw(); // certain classes that use scene2d.ui widgets need to be told to act() to process input. stage.act(); } @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.gridWidth, (float) height / (this.gridHeight + 8), this.gridWidth, this.gridHeight, 0, 0); } }