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@@ -28,7 +28,7 @@ a 256x256x256 cube of voxels.</p>
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<pre class="prettyprint showlinemods notranslate lang-js" translate="no">const cellSize = 256;
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const cell = new Uint8Array(cellSize * cellSize * cellSize);
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</pre>
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-<p>I then made a single layer with a kind of hills of
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+<p>I then made a single layer with a kind of hills of
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sine waves like this</p>
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<pre class="prettyprint showlinemods notranslate lang-js" translate="no">for (let y = 0; y < cellSize; ++y) {
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for (let z = 0; z < cellSize; ++z) {
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@@ -77,7 +77,7 @@ the problem is there are just way too many objects. 256x256
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is 65536 boxes!</p>
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<p>Using <a href="rendering-on-demand.html">the technique of merging the geometry</a>
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will fix the issue for this example but what if instead of just making
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-a single layer we filled in everything below the ground with voxel.
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+a single layer we filled in everything below the ground with voxel.
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In other words change the loop filling in the voxels to this</p>
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<pre class="prettyprint showlinemods notranslate lang-js" translate="no">for (let y = 0; y < cellSize; ++y) {
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for (let z = 0; z < cellSize; ++z) {
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@@ -124,7 +124,7 @@ if nothing else in much of the space nothing is there so that's a lot of wasted
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memory. It's also a huge number of voxels, 16 million! That's too much to
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consider at once.</p>
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<p>A solution is to divide the area into smaller areas.
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-Any area that has nothing in it needs no storage. Let's use
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+Any area that has nothing in it needs no storage. Let's use
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32x32x32 areas (that's 32k) and only create an area if something is in it.
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We'll call one of these larger 32x32x32 areas a "cell".</p>
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<p>Let's break this into pieces. First let's make a class to manage the voxel data.</p>
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@@ -134,7 +134,7 @@ We'll call one of these larger 32x32x32 areas a "cell".</p>
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}
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}
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</pre>
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-<p>Let's make the function that makes geometry for a cell.
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+<p>Let's make the function that makes geometry for a cell.
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Let's assume you pass in a cell position.
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In other words if you want the geometry for the cell that covers voxels (0-31x, 0-31y, 0-31z)
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then you'd pass in 0,0,0. For the cell that covers voxels (32-63x, 0-31y, 0-31z) you'd
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@@ -1072,13 +1072,13 @@ At the end we update the attributes and indices with the new data.</p>
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<p></p>
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<p>Some notes:</p>
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<p><code class="notranslate" translate="no">RayCaster</code> might have worked just fine. I didn't try it.
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-Instead I found <a href="http://www.cse.chalmers.se/edu/year/2010/course/TDA361/grid.pdf">a voxel specific raycaster</a>.
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+Instead I found <a href="https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.42.3443&rep=rep1&type=pdf">a voxel specific raycaster</a>.
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that is optimized for voxels.</p>
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<p>I made <code class="notranslate" translate="no">intersectRay</code> part of VoxelWorld because it seemed
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like if it gets too slow we could raycast against cells
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before raycasting on voxels as a simple speed up if it becomes
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too slow.</p>
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-<p>You might want to change the length of the raycast
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+<p>You might want to change the length of the raycast
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as currently it's all the way to Z-far. I expect if the
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user clicks something too far way they don't really want
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to be placing blocks on the other side of the world that
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@@ -1086,7 +1086,7 @@ are 1 or 2 pixel large.</p>
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<p>Calling <code class="notranslate" translate="no">geometry.computeBoundingSphere</code> might be slow.
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We could just manually set the bounding sphere to the fit
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the entire cell.</p>
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-<p>Do we want remove cells if all voxels in that cell are 0?
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+<p>Do we want remove cells if all voxels in that cell are 0?
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That would probably be reasonable change if we wanted to ship this.</p>
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<p>Thinking about how this works it's clear the absolute
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worst case is a checkerboard of on and off voxels. I don't
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@@ -1115,11 +1115,11 @@ to generate some what efficient geometry.</p>
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</div>
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</div>
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</div>
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-
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+
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<script src="/manual/resources/prettify.js"></script>
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<script src="/manual/resources/lesson.js"></script>
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-</body></html>
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+</body></html>
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Michael Herzog