Allow mob spawning on stone blocks

src/main/java/gregtech/api/block/IStateSpawnControl.java

@@ -0,0 +1,14 @@
+package gregtech.api.block;
+
+import net.minecraft.block.state.IBlockState;
+import net.minecraft.entity.EntityLiving;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.IBlockAccess;
+
+import org.jetbrains.annotations.NotNull;
+
+public interface IStateSpawnControl {
+
+    boolean canCreatureSpawn(@NotNull IBlockState state, @NotNull IBlockAccess world, @NotNull BlockPos pos,
+                             @NotNull EntityLiving.SpawnPlacementType type);
+}

src/main/java/gregtech/api/block/VariantBlock.java

@@ -13,10 +13,12 @@
 import net.minecraft.client.util.ITooltipFlag;
 import net.minecraft.creativetab.CreativeTabs;
 import net.minecraft.entity.Entity;
+import net.minecraft.entity.EntityLiving;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.IStringSerializable;
 import net.minecraft.util.NonNullList;
 import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.IBlockAccess;
 import net.minecraft.world.World;
 import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.relauncher.SideOnly;
@@ -125,6 +127,15 @@ public SoundType getSoundType(@NotNull IBlockState state, @NotNull World world,
         return super.getSoundType(state, world, pos, entity);
     }
 
+    @Override
+    public boolean canCreatureSpawn(@NotNull IBlockState state, @NotNull IBlockAccess world, @NotNull BlockPos pos,
+                                    @NotNull EntityLiving.SpawnPlacementType type) {
+        if (getState(state) instanceof IStateSpawnControl stateSpawnControl) {
+            return stateSpawnControl.canCreatureSpawn(state, world, pos, type);
+        }
+        return super.canCreatureSpawn(state, world, pos, type);
+    }
+
     // magic is here
     @SuppressWarnings("unchecked")
     protected static <T, R> Class<T> getActualTypeParameter(Class<? extends R> thisClass, Class<R> declaringClass) {

src/main/java/gregtech/common/blocks/StoneVariantBlock.java

@@ -1,5 +1,6 @@
 package gregtech.common.blocks;
 
+import gregtech.api.block.IStateSpawnControl;
 import gregtech.api.block.VariantBlock;
 import gregtech.api.items.toolitem.ToolClasses;
 import gregtech.api.unification.material.Material;
@@ -51,12 +52,6 @@ protected BlockStateContainer createBlockState() {
         return new BlockStateContainer(this, VARIANT);
     }
 
-    @Override
-    public boolean canCreatureSpawn(@NotNull IBlockState state, @NotNull IBlockAccess world, @NotNull BlockPos pos,
-                                    @NotNull EntityLiving.SpawnPlacementType type) {
-        return false;
-    }
-
     @Override
     protected boolean canSilkHarvest() {
         return this.stoneVariant == StoneVariant.SMOOTH;
@@ -69,21 +64,27 @@ public Item getItemDropped(@NotNull IBlockState state, @NotNull Random rand, int
                 MetaBlocks.STONE_BLOCKS.get(StoneVariant.COBBLE) : this);
     }
 
-    public enum StoneType implements IStringSerializable {
+    public enum StoneType implements IStringSerializable, IStateSpawnControl {
 
         BLACK_GRANITE("black_granite", MapColor.BLACK),
         RED_GRANITE("red_granite", MapColor.RED),
         MARBLE("marble", MapColor.QUARTZ),
         BASALT("basalt", MapColor.BLACK_STAINED_HARDENED_CLAY),
-        CONCRETE_LIGHT("concrete_light", MapColor.STONE),
-        CONCRETE_DARK("concrete_dark", MapColor.STONE);
+        CONCRETE_LIGHT("concrete_light", MapColor.STONE, false),
+        CONCRETE_DARK("concrete_dark", MapColor.STONE, false);
 
         private final String name;
+        private final boolean allowSpawn;
         public final MapColor mapColor;
 
         StoneType(@NotNull String name, @NotNull MapColor mapColor) {
+            this(name, mapColor, true);
+        }
+
+        StoneType(@NotNull String name, @NotNull MapColor mapColor, boolean allowSpawn) {
             this.name = name;
             this.mapColor = mapColor;
+            this.allowSpawn = allowSpawn;
         }
 
         @NotNull
@@ -108,6 +109,12 @@ public Material getMaterial() {
                 case CONCRETE_LIGHT, CONCRETE_DARK -> Materials.Concrete;
             };
         }
+
+        @Override
+        public boolean canCreatureSpawn(@NotNull IBlockState state, @NotNull IBlockAccess world, @NotNull BlockPos pos,
+                                        @NotNull EntityLiving.SpawnPlacementType type) {
+            return this.allowSpawn;
+        }
     }
 
     public enum StoneVariant {