added 3d simplex

src/main/java/carpet/script/Expression.java

@@ -2732,25 +2732,26 @@ public class Expression
      * map(range(10), str('%.1f',rand(_))) => [0.0, 0.4, 0.6, 1.9, 2.8, 3.8, 5.3, 2.2, 1.6, 5.6]
      * </pre>
      *
-     * <h3><code>perlin(x), perlin(x,y), perlin(x,y,z), perlin(x,y,z,seed)</code></h3>
-     * <p>returns a noise value from <code>0.0</code> to <code>1.0</code> (roughly) for 1, 2 or 3 dimensional coordinate. The default seed it samples from is <code>0</code>, but seed can be
+     * <h3><code>perlin(x), perlin(x, y), perlin(x, y, z), perlin(x, y, z, seed)</code></h3>
+     * <p>returns a noise value from <code>0.0</code> to <code>1.0</code> (roughly) for 1, 2 or 3 dimensional coordinate.
+     * The default seed it samples from is <code>0</code>, but seed can be
      * specified as a 4th argument as well. In case you need 1D or 2D noise values with custom seed, use <code>null</code>
      * for <code>z</code>, or <code>y</code> and <code>z</code> arguments respectively.</p>
-     * <p> Perlin noise is based on a square grid and generates rougher maps comparing to Simplex, which is creamier,
-     * but the in-game implementation allows to sample up to 3D noise. Querying for lower-dimensional result, rather than
+     * <p> Perlin noise is based on a square grid and generates rougher maps comparing to Simplex, which is creamier.
+     * Querying for lower-dimensional result, rather than
      * affixing unused dimensions to constants has a speed benefit,
      * </p>
      * <p>Thou shall not sample from noise changing seed frequently. Scarpet will keep track of the last 256 perlin seeds used for sampling
      * providing similar speed comparing to the default seed of <code>0</code>. In case the app engine uses more than 256 seeds at the same time,
      * switching between them can get much more expensive.</p>
      *
-     * <h3><code>simplex(x,y), simplex(x,y,seed)</code></h3>
-     * <p>returns a noise value from <code>0.0</code> to <code>1.0</code> (roughly) for 2 dimensional coordinate.
+     * <h3><code>simplex(x, y), simplex(x, y, z), simplex(x, y, z, seed)</code></h3>
+     * <p>returns a noise value from <code>0.0</code> to <code>1.0</code> (roughly) for 2 or 3 dimensional coordinate.
      * The default seed it samples from is <code>0</code>, but seed can be
-     * specified as a 3rd argument as well</p>
-     * <p> Simplex noise is based on a triangular grid and generates smoother maps comparing to Perlin,
-     * but the in-game implementation only allows to sample 2D noise. To sample 1D simplex noise, affix other coordinate
-     * to a constant.
+     * specified as a 4th argument as well. In case you need 2D noise values with custom seed, use <code>null</code>
+     * for <code>z</code> argument.</p>
+     * <p> Simplex noise is based on a triangular grid and generates smoother maps comparing to Perlin.
+     * To sample 1D simplex noise, affix other coordinate to a constant.
      * </p>
      * <p>Thou shall not sample from noise changing seed frequently. Scarpet will keep track of the last 256 simplex seeds used for sampling
      * providing similar speed comparing to the default seed of <code>0</code>. In case the app engine uses more than 256 seeds at the same time,
@@ -3044,16 +3045,37 @@ public class Expression
 
         addLazyFunction("simplex", -1, (c, t, lv) -> {
             SimplexNoiseSampler sampler;
-            if (lv.size() == 2)
-                sampler = SimplexNoiseSampler.instance;
-            else if (lv.size() == 3)
-                sampler = SimplexNoiseSampler.getSimplex(NumericValue.asNumber(lv.get(2).evalValue(c)).getLong());
+            Value x, y, z;
+
+            if (lv.size() >= 4)
+            {
+                x = lv.get(0).evalValue(c);
+                y = lv.get(1).evalValue(c);
+                z = lv.get(2).evalValue(c);
+                sampler = SimplexNoiseSampler.getSimplex(NumericValue.asNumber(lv.get(3).evalValue(c)).getLong());
+            }
             else
-                throw new InternalExpressionException("'simplex' requires two or three arguments");
-            double x = NumericValue.asNumber(lv.get(0).evalValue(c)).getDouble();
-            double y = NumericValue.asNumber(lv.get(1).evalValue(c)).getDouble();
-            Value value = new NumericValue(sampler.sample(x,y));
-            return (cc, tt) -> value;
+            {
+                sampler = SimplexNoiseSampler.instance;
+                z = Value.NULL;
+                if (lv.size() < 2 )
+                    throw new InternalExpressionException("'simplex' requires at least two dimensions to sample from");
+                x = NumericValue.asNumber(lv.get(0).evalValue(c));
+                y = NumericValue.asNumber(lv.get(1).evalValue(c));
+                if (lv.size() > 2)
+                    z = NumericValue.asNumber(lv.get(2).evalValue(c));
+            }
+            double result;
+
+            if (z instanceof NullValue)
+                result = sampler.sample2d(NumericValue.asNumber(x).getDouble(), NumericValue.asNumber(y).getDouble());
+            else
+                result = sampler.sample3d(
+                        NumericValue.asNumber(x).getDouble(),
+                        NumericValue.asNumber(y).getDouble(),
+                        NumericValue.asNumber(z).getDouble());
+            Value ret = new NumericValue(result);
+            return (cc, tt) -> ret;
         });
 
         addUnaryFunction("print", (v) ->