Source: Test.js

 
/** 
 * Heightmap manipulation functionality 
 * 
 * A heightmapt is an array of width arrays of height floats 
 * Width and height is normally mapSize+1 (Number of vertices is one bigger than number of tiles in each direction) 
 * The default heightmap is g_Map.height (See the Map object) 
 * 
 * @warning - Ambiguous naming and potential confusion: 
 * For using this heightmap functionalities it is VITAL that TILE_CENTERED_HEIGHT_MAP = false (default)! 
 * Otherwise TILE_CENTERED_HEIGHT_MAP has nothing to do with any tile centered heightmap in this library! 
 * All tile centered heightmaps in this module are temporary objects only and should never replace g_Map.height! 
 * (Tile centered heightmaps are one less in width and hight than heightmaps used by the engine) 
 * (Multiple conversions will lead to strange smoothing effects at best and potentially break the map entirely!) 
 * In the long run TILE_CENTERED_HEIGHT_MAP should be removed and g_Map.height should never be tile centered... 
 */ 
 
/** 
 * Get the height range of a heightmap 
 * @param {array} [heightmap=g_Map.height] - The reliefmap the minimum and maximum height should be determined for 
 * @return {object} [height] - Height range with 2 floats in properties "min" and "max" 
 */ 
function getMinAndMaxHeight(heightmap = g_Map.height) 
{ 
    var height = {}; 
    height.min = Infinity; 
    height.max = - Infinity; 
    for (let x = 0; x < heightmap.length; ++x) 
    { 
        for (let y = 0; y < heightmap[x].length; ++y) 
        { 
            if (heightmap[x][y] < height.min) 
                height.min = heightmap[x][y]; 
            else if (heightmap[x][y] > height.max) 
                height.max = heightmap[x][y]; 
        } 
    } 
    return height; 
} 
 
/** 
 * Rescales a heightmap so its minimum and maximum height is as the arguments told preserving it's global shape 
 * @param {float} [minHeight=MIN_HEIGHT] - Minimum height that should be used for the resulting heightmap 
 * @param {float} [maxHeight=MAX_HEIGHT] - Maximum height that should be used for the resulting heightmap 
 * @param {array} [heightmap=g_Map.height] - A reliefmap 
 * @todo Add preserveRatios to not change relative heights within the given height range 
 * @todo Add preserveCostline to leave a certain height untoucht and scale below and above that seperately 
 */ 
function rescaleHeightmap(minHeight = MIN_HEIGHT, maxHeight = MAX_HEIGHT, heightmap = g_Map.height) 
{ 
    var oldHeightRange = getMinAndMaxHeight(heightmap); 
    var max_x = heightmap.length; 
    var max_y = heightmap[0].length; 
    for (let x = 0; x < max_x; ++x) 
        for (let y = 0; y < max_y; ++y) 
            heightmap[x][y] = minHeight + (heightmap[x][y] - oldHeightRange.min) / (oldHeightRange.max - oldHeightRange.min) * (maxHeight - minHeight); 
} 
 
/** 
 * Get start location with the largest minimum distance between players 
 * @param {array} [hightRange] - The height range start locations are allowed 
 * @param {integer} [maxTries=1000] - How often random player distributions are rolled to be compared 
 * @param {float} [minDistToBorder=20.] - How far start locations have to be away from the map border 
 * @param {integer} [numberOfPlayers=g_MapSettings.PlayerData.length] - How many start locations should be placed 
 * @param {array} [heightmap=g_Map.height] - The reliefmap for the start locations to be placed on 
 * @return {array} [finalStartLoc] - Array of 2D points in the format { "x": float, "y": float} 
 */ 
function getStartLocationsByHeightmap(hightRange, maxTries = 1000, minDistToBorder = 20, numberOfPlayers = g_MapSettings.PlayerData.length - 1, heightmap = g_Map.height) 
{ 
    var validStartLoc = []; 
    for (let x = minDistToBorder; x < heightmap.length - minDistToBorder; ++x) 
        for (let y = minDistToBorder; y < heightmap[0].length - minDistToBorder; ++y) 
            if (heightmap[x][y] > hightRange.min && heightmap[x][y] < hightRange.max) // Is in height range 
                validStartLoc.push({ "x": x, "y": y }); 
     
    var maxMinDist = 0; 
    var finalStartLoc; 
    for (let tries = 0; tries < maxTries; ++tries) 
    { 
        var startLoc = []; 
        var minDist = heightmap.length; 
        for (let p = 0; p < numberOfPlayers; ++p) 
            startLoc.push(validStartLoc[randInt(validStartLoc.length)]); 
        for (let p1 = 0; p1 < numberOfPlayers - 1; ++p1) 
        { 
            for (let p2 = p1 + 1; p2 < numberOfPlayers; ++p2) 
            { 
                var dist = getDistance(startLoc[p1].x, startLoc[p1].y, startLoc[p2].x, startLoc[p2].y); 
                if (dist < minDist) 
                    minDist = dist; 
            } 
        } 
        if (minDist > maxMinDist) 
        { 
            maxMinDist = minDist; 
            finalStartLoc = startLoc; 
        } 
    } 
     
    return finalStartLoc; 
} 
 
/** 
 * Meant to place e.g. resource spots within a hight range 
 * @param {array} [hightRange] - The height range in which to place the entities (An associative array with keys "min" and "max" each containing a float) 
 * @param {array} [avoidPoints] - An array of 2D points (arrays of length 2), points that will be avoided in the given minDistance e.g. start locations 
 * @param {integer} [minDistance=30] - How many tile widths the entities to place have to be away from each other, start locations and the map border 
 * @param {array} [heightmap=g_Map.height] - The reliefmap the entities should be distributed on 
 * @param {array} [entityList=[g_Gaia.stoneLarge, g_Gaia.metalLarge]] - Entity/actor strings to be placed with placeObject() 
 * @param {integer} [maxTries=1000] - How often random player distributions are rolled to be compared 
 */ 
function distributeEntitiesByHeight(hightRange, avoidPoints, minDistance = 30, entityList = [g_Gaia.stoneLarge, g_Gaia.metalLarge], maxTries = 1000, heightmap = g_Map.height) 
{ 
    var placements = deepcopy(avoidPoints); 
    var validTiles = []; 
    for (let x = minDistance; x < heightmap.length - minDistance; ++x) 
        for (let y = minDistance; y < heightmap[0].length - minDistance; ++y) 
            if (heightmap[x][y] > hightRange.min && heightmap[x][y] < hightRange.max) // Has the right hight 
                validTiles.push({ "x": x, "y": y }); 
     
    for (let tries = 0; tries < maxTries; ++tries) 
    { 
        var tile = validTiles[randInt(validTiles.length)]; 
        var isValid = true; 
        for (let p = 0; p < placements.length; ++p) 
        { 
            if (getDistance(placements[p].x, placements[p].y, tile.x, tile.y) < minDistance) 
            { 
                isValid = false; 
                break; 
            } 
        } 
        if (isValid) 
        { 
            placeObject(tile.x, tile.y, entityList[randInt(entityList.length)], 0, randFloat(0, 2*PI)); 
            placements.push(tile); 
        } 
    } 
} 
 
/** 
 * Sets a given heightmap to entirely random values within a given range 
 * @param {float} [minHeight=MIN_HEIGHT] - Lower limit of the random height to be rolled 
 * @param {float} [maxHeight=MAX_HEIGHT] - Upper limit of the random height to be rolled 
 * @param {array} [heightmap=g_Map.height] - The reliefmap that should be randomized 
 */ 
function setRandomHeightmap(minHeight = MIN_HEIGHT, maxHeight = MAX_HEIGHT, heightmap = g_Map.height) 
{ 
    for (let x = 0; x < heightmap.length; ++x) 
        for (let y = 0; y < heightmap[0].length; ++y) 
            heightmap[x][y] = randFloat(minHeight, maxHeight); 
} 
 
/** 
 * Sets the heightmap to a relatively realistic shape 
 * @note min/maxHeight will not necessarily be present in the heightmap 
 * @note On circular maps the edges (given by initialHeightmap) may not be in the playable map area 
 * The function doubles the size of the initial heightmap (if given, else a random 2x2 one) until it's big enough. 
 * Then the extend is cut off. So the impact and scale of the initial heightmap depends on its size and the target map size! 
 * @param {float} [minHeight=MIN_HEIGHT] - Lower limit of the random height to be rolled 
 * @param {float} [maxHeight=MAX_HEIGHT] - Upper limit of the random height to be rolled 
 * @param {array} [initialHeightmap] - Optional, Small (e.g. 3x3) heightmap describing the global shape of the map e.g. an island [[MIN_HEIGHT, MIN_HEIGHT, MIN_HEIGHT], [MIN_HEIGHT, MAX_HEIGHT, MIN_HEIGHT], [MIN_HEIGHT, MIN_HEIGHT, MIN_HEIGHT]] 
 * @param {float} [smoothness=0.5] - Float between 0 (rough, more local structures) to 1 (smoother, only larger scale structures) 
 * @param {array} [heightmap=g_Map.height] - The reliefmap that will be set by this function 
 */ 
function setBaseTerrainDiamondSquare(minHeight = MIN_HEIGHT, maxHeight = MAX_HEIGHT, initialHeightmap = undefined, smoothness = 0.5, heightmap = g_Map.height) 
{ 
    initialHeightmap = (initialHeightmap || [[randFloat(minHeight / 2, maxHeight / 2), randFloat(minHeight / 2, maxHeight / 2)], [randFloat(minHeight / 2, maxHeight / 2), randFloat(minHeight / 2, maxHeight / 2)]]); 
    var heightRange = maxHeight - minHeight; 
    if (heightRange <= 0) 
        warn("setBaseTerrainDiamondSquare: heightRange <= 0"); 
     
    var offset = heightRange / 2; 
     
    // Double initialHeightmap width until target width is reached (diamond square method) 
    while (initialHeightmap.length < heightmap.length) 
    { 
        var newHeightmap = []; 
        var oldWidth = initialHeightmap.length; 
        // Square 
        for (let x = 0; x < 2 * oldWidth - 1; ++x) 
        { 
            newHeightmap.push([]); 
            for (let y = 0; y < 2 * oldWidth - 1; ++y) 
            { 
                if (x % 2 == 0 && y % 2 == 0) // Old tile 
                    newHeightmap[x].push(initialHeightmap[x/2][y/2]); 
                else if (x % 2 == 1 && y % 2 == 1) // New tile with diagonal old tile neighbors 
                { 
                    newHeightmap[x].push((initialHeightmap[(x-1)/2][(y-1)/2] + initialHeightmap[(x+1)/2][(y-1)/2] + initialHeightmap[(x-1)/2][(y+1)/2] + initialHeightmap[(x+1)/2][(y+1)/2]) / 4); 
                    newHeightmap[x][y] += (newHeightmap[x][y] - minHeight) / heightRange * randFloat(-offset, offset); 
                } 
                else // New tile with straight old tile neighbors 
                    newHeightmap[x].push(undefined); // Define later 
            } 
        } 
        // Diamond 
        for (let x = 0; x < 2 * oldWidth - 1; ++x) 
        { 
            for (let y = 0; y < 2 * oldWidth - 1; ++y) 
            { 
                if (newHeightmap[x][y] !== undefined) 
                    continue; 
                 
                if (x > 0 && x + 1 < newHeightmap.length - 1 && y > 0 && y + 1 < newHeightmap.length - 1) // Not a border tile 
                { 
                    newHeightmap[x][y] = (newHeightmap[x+1][y] + newHeightmap[x][y+1] + newHeightmap[x-1][y] + newHeightmap[x][y-1]) / 4; 
                    newHeightmap[x][y] += (newHeightmap[x][y] - minHeight) / heightRange * randFloat(-offset, offset); 
                } 
                else if (x < newHeightmap.length - 1 && y > 0 && y < newHeightmap.length - 1) // Left border 
                { 
                    newHeightmap[x][y] = (newHeightmap[x+1][y] + newHeightmap[x][y+1] + newHeightmap[x][y-1]) / 3; 
                    newHeightmap[x][y] += (newHeightmap[x][y] - minHeight) / heightRange * randFloat(-offset, offset); 
                } 
                else if (x > 0 && y > 0 && y < newHeightmap.length - 1) // Right border 
                { 
                    newHeightmap[x][y] = (newHeightmap[x][y+1] + newHeightmap[x-1][y] + newHeightmap[x][y-1]) / 3; 
                    newHeightmap[x][y] += (newHeightmap[x][y] - minHeight) / heightRange * randFloat(-offset, offset); 
                } 
                else if (x > 0 && x < newHeightmap.length - 1 && y < newHeightmap.length - 1) // Bottom border 
                { 
                    newHeightmap[x][y] = (newHeightmap[x+1][y] + newHeightmap[x][y+1] + newHeightmap[x-1][y]) / 3; 
                    newHeightmap[x][y] += (newHeightmap[x][y] - minHeight) / heightRange * randFloat(-offset, offset); 
                } 
                else if (x > 0 && x < newHeightmap.length - 1 && y > 0) // Top border 
                { 
                    newHeightmap[x][y] = (newHeightmap[x+1][y] + newHeightmap[x-1][y] + newHeightmap[x][y-1]) / 3; 
                    newHeightmap[x][y] += (newHeightmap[x][y] - minHeight) / heightRange * randFloat(-offset, offset); 
                } 
            } 
        } 
        initialHeightmap = deepcopy(newHeightmap); 
        offset /= Math.pow(2, smoothness); 
    } 
     
    // Cut initialHeightmap to fit target width 
    var shift = [floor((newHeightmap.length - heightmap.length) / 2), floor((newHeightmap[0].length - heightmap[0].length) / 2)]; 
    for (let x = 0; x < heightmap.length; ++x) 
        for (let y = 0; y < heightmap[0].length; ++y) 
            heightmap[x][y] = newHeightmap[x + shift[0]][y + shift[1]]; 
} 
 
/** 
 * Smoothens the entire map 
 * @param {float} [strength=0.8] - How strong the smooth effect should be: 0 means no effect at all, 1 means quite strong, higher values might cause interferences, better apply it multiple times 
 * @param {array} [heightmap=g_Map.height] - The heightmap to be smoothed 
 * @param {array} [smoothMap=[[1, 0], [1, 1], [0, 1], [-1, 1], [-1, 0], [-1, -1], [0, -1], [1, -1]]] - Array of offsets discribing the neighborhood tiles to smooth the height of a tile to 
 */ 
function globalSmoothHeightmap(strength = 0.8, heightmap = g_Map.height, smoothMap = [[1, 0], [1, 1], [0, 1], [-1, 1], [-1, 0], [-1, -1], [0, -1], [1, -1]]) 
{ 
    var referenceHeightmap = deepcopy(heightmap); 
    var max_x = heightmap.length; 
    var max_y = heightmap[0].length; 
    for (let x = 0; x < max_x; ++x) 
    { 
        for (let y = 0; y < max_y; ++y) 
        { 
            for (let i = 0; i < smoothMap.length; ++i) 
            { 
                var mapX = x + smoothMap[i][0]; 
                var mapY = y + smoothMap[i][1]; 
                if (mapX >= 0 && mapX < max_x && mapY >= 0 && mapY < max_y) 
                    heightmap[x][y] += strength / smoothMap.length * (referenceHeightmap[mapX][mapY] - referenceHeightmap[x][y]); 
            } 
        } 
    } 
} 
 
/** 
 * Pushes a rectangular area towards a given height smoothing it into the original terrain 
 * @note The window function to determine the smooth is not exactly a gaussian to ensure smooth edges 
 * @param {object} [center] - The x and y coordinates of the center point (rounded in this function) 
 * @param {float} [dx] - Distance from the center in x direction the rectangle ends (half width, rounded in this function) 
 * @param {float} [dy] - Distance from the center in y direction the rectangle ends (half depth, rounded in this function) 
 * @param {float} [targetHeight] - Height the center of the rectangle will be pushed to 
 * @param {float} [strength=1] - How strong the height is pushed: 0 means not at all, 1 means the center will be pushed to the target height 
 * @param {array} [heightmap=g_Map.height] - The heightmap to be manipulated 
 * @todo Make the window function an argument and maybe add some 
 */ 
function rectangularSmoothToHeight(center, dx, dy, targetHeight, strength = 0.8, heightmap = g_Map.height) 
{ 
    var x = round(center.x); 
    var y = round(center.y); 
    dx = round(dx); 
    dy = round(dy); 
     
    var heightmapWin = []; 
    for (let wx = 0; wx < 2 * dx + 1; ++wx) 
    { 
        heightmapWin.push([]); 
        for (let wy = 0; wy < 2 * dy + 1; ++wy) 
        { 
            var actualX = x - dx + wx; 
            var actualY = y - dy + wy; 
            if (actualX >= 0 && actualX < heightmap.length - 1 && actualY >= 0 && actualY < heightmap[0].length - 1) // Is in map 
                heightmapWin[wx].push(heightmap[actualX][actualY]); 
            else 
                heightmapWin[wx].push(targetHeight); 
        } 
    } 
    for (let wx = 0; wx < 2 * dx + 1; ++wx) 
    { 
        for (let wy = 0; wy < 2 * dy + 1; ++wy) 
        { 
            var actualX = x - dx + wx; 
            var actualY = y - dy + wy; 
            if (actualX >= 0 && actualX < heightmap.length - 1 && actualY >= 0 && actualY < heightmap[0].length - 1) // Is in map 
            { 
                // Window function polynomial 2nd degree 
                var scaleX = 1 - (wx / dx - 1) * (wx / dx - 1); 
                var scaleY = 1 - (wy / dy - 1) * (wy / dy - 1); 
                 
                heightmap[actualX][actualY] = heightmapWin[wx][wy] + strength * scaleX * scaleY * (targetHeight - heightmapWin[wx][wy]); 
            } 
        } 
    } 
}