AndEngine动态更改TMX平铺地图

Question

I have read all the possible duplicates of this question and none gives me a full solution (the solution is in divided into the answers) so I decided to try and clear the things up. BTW StackOverflow told me:

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and

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So [...] if you'd like to document it in public so others (including yourself) can find it later

Now this being clear, I would like to change a TMX map dynamically. For example the map has a chest object. The player walks on it and receives gold. Then I would like to remove the chest from the map so the player cannot collect the chest more than once. How do I do this?

Answer 1

Removing the chest from the map so it can no longer be collected is possible, but not by editing the TMX Map. To accomplish this, whenever the player walks over a chest (check by adding a property to the chest like chest=true and then checking it), besides rewarding the player, you must do something, and that is saving using Shared Preferences which chests have been used using a String Set (eg. with the key "chests") and containing the coordinates, separated by ":". To save the coordinates:

String saveMe = tileRow + ":" + tileColumn;
removeChest(tileRow, tileColumn);

To load the coordinates:

String loaded = loadString();
String[] coords = loades.split(":");
tileRow = Integer.parseInt(coords[0]);
tileColumn = Integer.parseInt(coords[1]);
removeChest(tileRow, tileColumn);

Now you can save / load used chests. This is whenever the player walks over a tile which has (chest=true) property:

boolean found = false;
for (int i = 0; i < chestsUsedTileRowsArray.length; i++) {
    if (chestFoundTileRow == chestsUsedTileRowsArray[i] && chestFoundTileColumn == chestsUsedTileColumnsArray[i]) {
        found = true;
        break;
    }
}
if (!found) {
    rewardPlayer();
    saveChestUsed(tileRow, tileColumn);
}

Finally, there is removeChest() which requires a little trick: drawing a sprite which has the texture of the ground on the chest:

void removeChest(int tileRow, int tileColumn) {
    final TMXTile tileToReplace = tmxMap.getTMXLayers().get(0).getTMXTile(tileColumn, tileRow);
    final int w = tileToReplace.getTileWidth();
    final int h = tileToReplace.getTileHeight();
    Sprite sprite = new Sprite(w * (tileColumn + 0.5), h * (tileRow + 0.5), textureRegionOfGround, this.getVertexBufferObjectManager());
    scene.addChild(sprite);
}