phaser/src/gameobjects/tilemap/dynamiclayer/DynamicTilemapLayerCanvasRenderer.js

var GameObject = require('../../GameObject');

var DynamicTilemapLayerCanvasRenderer = function (renderer, gameObject, interpolationPercentage, camera)
{
    if (GameObject.RENDER_MASK !== gameObject.renderFlags || (gameObject.cameraFilter > 0 && (gameObject.cameraFilter & camera._id)))
    {
        return;
    }

    gameObject.cull(camera);

    var renderTiles = gameObject.culledTiles;
    var length = renderTiles.length;
    var image = gameObject.frame.source.image;
    var tileset = this.tileset;

    var tx = gameObject.x - camera.scrollX * gameObject.scrollFactorX;
    var ty = gameObject.y - camera.scrollY * gameObject.scrollFactorY;
    var ctx = renderer.gameContext;

    ctx.save();
    ctx.translate(tx, ty);
    ctx.rotate(gameObject.rotation);
    ctx.scale(gameObject.scaleX, gameObject.scaleY);
    ctx.scale(gameObject.flipX ? -1 : 1, gameObject.flipY ? -1 : 1);

    for (var index = 0; index < length; ++index)
    {
        var tile = renderTiles[index];

        var tileTexCoords = tileset.getTileTextureCoordinates(tile.index);
        if (tileTexCoords === null) { continue; }

        var halfWidth = tile.width / 2;
        var halfHeight = tile.height / 2;

        ctx.save();
        ctx.translate(tile.pixelX + halfWidth, tile.pixelY + halfHeight);

        if (tile.flipX || tile.flipY)
        {
            ctx.scale(tile.flipX ? -1 : 1, tile.flipY ? -1 : 1);
        }

        ctx.globalAlpha = gameObject.alpha * tile.alpha;

        ctx.drawImage(
            image,
            tileTexCoords.x, tileTexCoords.y,
            tile.width, tile.height,
            -halfWidth, -halfHeight,
            tile.width, tile.height
        );

        ctx.restore();
    }

    ctx.restore();
};

module.exports = DynamicTilemapLayerCanvasRenderer;