One tooltip in MV

src/main/java/growthcraft/milk/block/MixingVatBlock.java

@@ -223,7 +223,19 @@ public <T extends BlockEntity> BlockEntityTicker<T> getTicker(Level level, Block
     protected void onRemove(BlockState state, Level level, BlockPos pos, BlockState newState, boolean movedByPiston) {
         if (!state.is(newState.getBlock())) {
             if (!level.isClientSide && level.getBlockEntity(pos) instanceof MixingVatBlockEntity vat) {
-                Containers.dropContents(level, pos, vat);
+                for(int i = 0; i < vat.getContainerSize(); ++i) {
+                    if (i == MixingVatBlockEntity.SLOT_RESULT_TOOL) {
+                        continue; // it's a fake/virtual slot for transferring information to screen.
+                    }
+                    if (i == MixingVatBlockEntity.SLOT_RESULT) {
+                        // here's the deal: if there is a pickup-item needed (cloth), no drop. if it can be collected by hand, we drop.
+                        if (! vat.getItem(MixingVatBlockEntity.SLOT_RESULT_TOOL).isEmpty()) {
+                            continue;
+                        }
+                    }
+                    Containers.dropItemStack(level, pos.getX(), pos.getY(), pos.getZ(), vat.getItem(i));
+                }
+
             }
             super.onRemove(state, level, pos, newState, movedByPiston);
         }

src/main/java/growthcraft/milk/block/entity/MixingVatBlockEntity.java

@@ -41,7 +41,8 @@ public class MixingVatBlockEntity extends BlockEntity implements WorldlyContaine
     public static final int SLOT_INPUT_1 = 1;
     public static final int SLOT_INPUT_2 = 2;
     public static final int SLOT_RESULT = 3;
-    public static final int SLOT_COUNT = 4;
+    public static final int SLOT_RESULT_TOOL = 4;
+    public static final int SLOT_COUNT = 5;
     public static final int MAIN_TANK_CAPACITY = 4000;
     public static final int SIDE_TANK_CAPACITY = 1000;
 
@@ -70,12 +71,12 @@ protected void onContentsChanged() {
     }
 
     public static void serverTick(Level level, BlockPos pos, BlockState state, MixingVatBlockEntity vat) {
-        if ((level.getGameTime() & 19L) == 0L) {
+        if ((level.getGameTime() & 19L) == 0L) {    // todo: ????
             updateLitState(level, pos, state);
             state = level.getBlockState(pos);
         }
 
-        Optional<RecipeHolder<MixingVatRecipe>> match = vat.findMatch(level, state);
+        Optional<RecipeHolder<MixingVatRecipe>> match = vat.findMatch(level, state);  // todo: horrible perf issue here
         if (match.isEmpty() || !vat.activated || !vat.canOutput(match.get().value())) {
             if (match.isEmpty()) {
                 vat.resetProgress();
@@ -84,11 +85,11 @@ public static void serverTick(Level level, BlockPos pos, BlockState state, Mixin
         }
 
         MixingVatRecipe recipe = match.get().value();
-        vat.processTimeTotal = recipe.getProcessingTime();
-        vat.processTime++;
+        vat.processTimeTotal = recipe.getProcessingTime(); // todo  only needed once on start
+        vat.processTime++;        // todo keeps inc after total
         if (vat.processTime >= vat.processTimeTotal) {
-            vat.completeRecipe(level, pos, state, recipe);
-        } else if ((vat.processTime & 15) == 0) {
+            vat.completeRecipe(level, pos, state, recipe); // todo math allows it done multiple times, relies on recipe check
+        } else if ((vat.processTime & 15) == 0) {  // todo why?
             vat.setChanged();
             level.sendBlockUpdated(pos, state, state, Block.UPDATE_CLIENTS);
         }
@@ -155,6 +156,7 @@ private void completeRecipe(Level level, BlockPos pos, BlockState state, MixingV
             mainTank.setFluid(FluidStack.EMPTY);
             sideTank.setFluid(FluidStack.EMPTY);
             setItem(SLOT_RESULT, recipe.getResultItemStack());
+            setItem(SLOT_RESULT_TOOL, recipe.getResultActivationTool());
         }
         activated = false;
         processTime = 0;
@@ -199,18 +201,15 @@ public boolean collectResult(Player player, ItemStack heldStack) {
             return false;
         }
 
-        Optional<RecipeHolder<MixingVatRecipe>> match = level == null ? Optional.empty()
-                : level.getRecipeManager().getAllRecipesFor(GrowthcraftMilkRecipes.MIXING_VAT_TYPE.get()).stream()
-                        .filter(holder -> ItemStack.isSameItemSameComponents(holder.value().getResultItemStack(), result))
-                        .findFirst();
-        ItemStack tool = match.map(holder -> holder.value().getResultActivationTool()).orElse(ItemStack.EMPTY);
-        if (!tool.isEmpty() && !ItemStack.isSameItem(tool, heldStack)) {
+        ItemStack resultActivationItem = getItem(SLOT_RESULT_TOOL);
+        if (!resultActivationItem.isEmpty() && !ItemStack.isSameItem(resultActivationItem, heldStack)) {
             return false;
         }
 
         ItemStack toGive = result.copy();
         setItem(SLOT_RESULT, ItemStack.EMPTY);
-        if (!tool.isEmpty() && !player.getAbilities().instabuild) {
+        setItem(SLOT_RESULT_TOOL, ItemStack.EMPTY);
+        if (!resultActivationItem.isEmpty() && !player.getAbilities().instabuild) {
             heldStack.shrink(1);
         }
         if (!player.addItem(toGive)) {

src/main/java/growthcraft/milk/client/screen/MixingVatScreen.java

@@ -1,14 +1,19 @@
 package growthcraft.milk.client.screen;
 
 import growthcraft.lib.client.screen.renderer.FluidTankRenderer;
+import growthcraft.milk.block.entity.MixingVatBlockEntity;
 import growthcraft.milk.menu.MixingVatMenu;
 import net.minecraft.client.gui.GuiGraphics;
 import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
 import net.minecraft.network.chat.Component;
+import net.minecraft.network.chat.Style;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.item.ItemStack;
 import net.neoforged.neoforge.fluids.FluidStack;
 
+import java.util.List;
+
 public class MixingVatScreen extends AbstractContainerScreen<MixingVatMenu> {
     private static final ResourceLocation TEXTURE = ResourceLocation.fromNamespaceAndPath("growthcraft_milk", "textures/gui/mixing_vat_screen.png");
 
@@ -123,6 +128,33 @@ public void render(GuiGraphics graphics, int mouseX, int mouseY, float partialTi
         this.renderTooltip(graphics, mouseX, mouseY);
     }
 
+    @Override
+    protected void renderTooltip(GuiGraphics guiGraphics, int x, int y) {
+
+        if (this.menu.getCarried().isEmpty() && this.hoveredSlot != null && this.hoveredSlot.index == 3 && this.hoveredSlot.hasItem()) {
+            // result slot
+            ItemStack finalizerItem = this.getMenu().getResultActivationTool();
+            ItemStack resultItemStack = this.hoveredSlot.getItem();
+            if (this.lastResultItem != resultItemStack.hashCode()) {
+                this.tooltipLines = this.getTooltipFromContainerItem(resultItemStack);
+                if (finalizerItem != null) {
+                    Component finalizerText = finalizerItem.isEmpty() ? Component.translatable("message.growthcraft_milk.get_using_item_empty_hand").withStyle(Style.EMPTY.withColor(0xffffff88)) : finalizerItem.getHoverName().copy().withStyle(Style.EMPTY.withColor(0xffffff88));
+                    this.lastComponent = Component.translatable("message.growthcraft_milk.get_using_item", finalizerText).withStyle(Style.EMPTY.withColor(0xffddbb44));
+                    this.tooltipLines.add(this.lastComponent);
+                }
+                this.lastResultItem = resultItemStack.hashCode();
+            }
+            guiGraphics.renderTooltip(this.font, tooltipLines, resultItemStack.getTooltipImage(), resultItemStack, x, y);
+        }
+        else {
+            // not a result slot
+            super.renderTooltip(guiGraphics, x, y);
+        }
+    }
+    private int lastResultItem = 0;
+    private Component lastComponent = null;
+    private List<Component> tooltipLines = null;
+
     @Override
     protected void renderLabels(GuiGraphics graphics, int mouseX, int mouseY) {
         graphics.drawString(this.font, this.title, 8, 6, 4210752, false);

src/main/java/growthcraft/milk/menu/MixingVatMenu.java

@@ -12,6 +12,7 @@
 import net.minecraft.world.inventory.SimpleContainerData;
 import net.minecraft.world.inventory.Slot;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.Items;
 import net.neoforged.neoforge.fluids.FluidStack;
 import org.jetbrains.annotations.Nullable;
 
@@ -106,6 +107,16 @@ public boolean mayPickup(Player player) {
                 return false;
             }
         });
+        this.addSlot(new Slot(container, MixingVatBlockEntity.SLOT_RESULT+1, 99999, 99999) {
+            @Override
+            public boolean mayPlace(ItemStack stack) { return false; }
+            @Override
+            public boolean mayPickup(Player player) { return false; }
+            @Override
+            public boolean isFake() { return true; }
+            @Override
+            public boolean isActive() { return false; }
+        });
 
         int startX = 8;
         int startY = 84;
@@ -206,4 +217,9 @@ public ItemStack quickMoveStack(Player player, int index) {
         }
         return itemstack;
     }
+
+    public ItemStack getResultActivationTool()
+    {
+        return this.slots.get(MixingVatBlockEntity.SLOT_RESULT_TOOL).getItem();
+    }
 }