Databases
StackOverflow2013
Postsdbo
PORandom spawn algorithm does not generate correctly
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PORandom spawn algorithm does not generate correctly
    primarykey
    data
    text
    <p>I have this code to spawn a 'tree' in my Java game; it works and spawns a 'tree'. I decided to make a random number generator up to 30 which would spawn that many 'trees'. However, when I run my code, I get no error but the 'trees' don't spawn. The spawning algorithm can be found below.</p> <pre><code>private void generateLevel() { int dungeonCoord = dungeonSpawn.nextInt(height * width); for (int y = 0; y &lt; height; y++) { for (int x = 0; x &lt; width; x++) { tiles[x + y * width] = Tile.GRASS.getId(); tiles[dungeonCoord] = Tile.TUNNEL.getId(); while(tCount &lt; tRan) { System.out.println(tRan); tCount ++; int treeX = treeSpawn.nextInt(width * 5); if(treeX &lt; 256) { treeX = 256; }else { tiles[treeX] = Tile.LOG.getId(); tiles[treeX + width] = Tile.LOG.getId(); tiles[treeX + width + width] = Tile.LOG.getId(); tiles[treeX - width] = Tile.LEAVES.getId(); tiles[treeX - width] = Tile.LEAVES.getId(); tiles[treeX - width - width] = Tile.LEAVES.getId(); tiles[treeX - width - width + 1] = Tile.LEAVES.getId(); tiles[treeX - width - width - 1] = Tile.LEAVES.getId(); tiles[treeX - width + 1] = Tile.LEAVES.getId(); tiles[treeX - width + 2] = Tile.LEAVES.getId(); tiles[treeX - width - 1] = Tile.LEAVES.getId(); tiles[treeX - width - 2] = Tile.LEAVES.getId(); tiles[treeX + 1] = Tile.LEAVES.getId(); tiles[treeX - 1] = Tile.LEAVES.getId(); tiles[treeX - width - width - width] = Tile.LEAVES.getId(); } } } } } </code></pre> <p>How everything is declared:</p> <pre><code>private byte[] tiles; public int width; public int height; public boolean generateTree = true; Random treeSpawn = new Random(); Random dungeonSpawn = new Random(); Random numTrees = new Random(); int tCount = 0; int tRan = numTrees.nextInt(30); </code></pre> <p>The <code>treeSpawn</code> boolean is for later on.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USJason C
    1. USuser2687097
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COHow have you determined that the trees aren't spawning?
      singulars
      1. PORandom spawn algorithm does not generate correctly
      1. USJason C
    2. CONot entirely sure what's causing the problem from what I'm reading, however the statement `if ( treeX < 256 ) { treeX = 256; } else ...` would not behave the way I think you'd expect. If `treeX` is less than 256, your trees would never be drawn because you used `else`. Based on the way you set `treeX` to 256 inside the `if` statement, I'm guessing the `else` was unintentional and you still want to draw the tree.
      singulars
      1. PORandom spawn algorithm does not generate correctly
      1. USJimmy Thompson
    3. COAlso, looking at your code, the general formula for a `tiles` index given X and Y is `tiles[x + y * width]`; but the way you are indexing tiles doesn't seem right (or you haven't fully explained the expected behavior). Why does `treeX` have range 0 to width*5? What's with all the adding and subtracting of `width`?
      singulars
      1. PORandom spawn algorithm does not generate correctly
      1. USJason C
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload