Added the ability to see the output of a Pattern by shift clicking

src/main/java/refinedstorage/item/ItemPattern.java

@@ -21,12 +21,15 @@ import refinedstorage.api.storage.CompareUtils;
 import refinedstorage.apiimpl.autocrafting.CraftingPattern;
 
 import javax.annotation.Nonnull;
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
+import java.util.*;
 
 public class ItemPattern extends ItemBase implements ICraftingPatternProvider {
+    /**
+     * A cache that maps a stack to a crafting pattern.
+     * Only used client side for rendering and tooltips, to avoid crafting pattern allocations and crafting pattern output calculation (which is expensive).
+     */
+    private static Map<ItemStack, CraftingPattern> PATTERN_CACHE = new HashMap<>();
+
     private static final String NBT_SLOT = "Slot_%d";
     private static final String NBT_OUTPUTS = "Outputs";
     private static final String NBT_OREDICTED = "Oredicted";
@@ -35,13 +38,21 @@ public class ItemPattern extends ItemBase implements ICraftingPatternProvider {
         super("pattern");
     }
 
+    public static CraftingPattern getPatternFromCache(World world, ItemStack stack) {
+        if (!PATTERN_CACHE.containsKey(stack)) {
+            PATTERN_CACHE.put(stack, new CraftingPattern(world, null, stack));
+        }
+
+        return PATTERN_CACHE.get(stack);
+    }
+
     @Override
     public void addInformation(ItemStack stack, EntityPlayer player, List<String> tooltip, boolean advanced) {
         if (!stack.hasTagCompound()) {
             return;
         }
 
-        ICraftingPattern pattern = create(player.worldObj, stack, null);
+        ICraftingPattern pattern = getPatternFromCache(player.worldObj, stack);
 
         if (pattern.isValid()) {
             if (GuiScreen.isShiftKeyDown() || isProcessing(stack)) {

src/main/java/refinedstorage/item/PatternBakedModel.java

@@ -0,0 +1,75 @@
+package refinedstorage.item;
+
+import net.minecraft.block.state.IBlockState;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.block.model.BakedQuad;
+import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.block.model.ItemCameraTransforms;
+import net.minecraft.client.renderer.block.model.ItemOverrideList;
+import net.minecraft.client.renderer.texture.TextureAtlasSprite;
+import net.minecraft.entity.EntityLivingBase;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.EnumFacing;
+import net.minecraft.world.World;
+import refinedstorage.apiimpl.autocrafting.CraftingPattern;
+import refinedstorage.gui.GuiBase;
+
+import javax.annotation.Nullable;
+import java.util.List;
+
+public class PatternBakedModel implements IBakedModel {
+    private IBakedModel patternModel;
+
+    public PatternBakedModel(IBakedModel patternModel) {
+        this.patternModel = patternModel;
+    }
+
+    @Override
+    public List<BakedQuad> getQuads(@Nullable IBlockState state, @Nullable EnumFacing side, long rand) {
+        return patternModel.getQuads(state, side, rand);
+    }
+
+    @Override
+    public boolean isAmbientOcclusion() {
+        return patternModel.isAmbientOcclusion();
+    }
+
+    @Override
+    public boolean isGui3d() {
+        return patternModel.isGui3d();
+    }
+
+    @Override
+    public boolean isBuiltInRenderer() {
+        return patternModel.isBuiltInRenderer();
+    }
+
+    @Override
+    public TextureAtlasSprite getParticleTexture() {
+        return patternModel.getParticleTexture();
+    }
+
+    @Override
+    @SuppressWarnings("deprecation")
+    public ItemCameraTransforms getItemCameraTransforms() {
+        return patternModel.getItemCameraTransforms();
+    }
+
+    @Override
+    public ItemOverrideList getOverrides() {
+        return new ItemOverrideList(patternModel.getOverrides().getOverrides()) {
+            @Override
+            public IBakedModel handleItemState(IBakedModel originalModel, ItemStack stack, World world, EntityLivingBase entity) {
+                CraftingPattern pattern = ItemPattern.getPatternFromCache(world, stack);
+
+                if (GuiBase.isShiftKeyDown() && pattern.isValid() && pattern.getOutputs().size() == 1) {
+                    ItemStack output = pattern.getOutputs().get(0);
+
+                    return Minecraft.getMinecraft().getRenderItem().getItemModelWithOverrides(output, world, entity);
+                }
+
+                return super.handleItemState(originalModel, stack, world, entity);
+            }
+        };
+    }
+}

src/main/java/refinedstorage/proxy/ClientProxy.java

@@ -42,6 +42,10 @@ public class ClientProxy extends CommonProxy {
                     e.getModelRegistry().putObject(model, ModelMultipartContainer.fromBlock(e.getModelRegistry().getObject(model), cable));
                 }
             }
+
+            if (model.getResourceDomain().equals(RefinedStorage.ID) && model.getResourcePath().equals("pattern")) {
+                e.getModelRegistry().putObject(model, new PatternBakedModel(e.getModelRegistry().getObject(model)));
+            }
         }
     }