Closes Anuken/Mindustry-Suggestions/issues/4608

core/assets/bundles/bundle.properties

@@ -2237,7 +2237,7 @@ lst.operation = Perform an operation on 1-2 variables.
 lst.end = Jump to the top of the instruction stack.
 lst.wait = Wait a certain number of seconds.
 lst.stop = Halt execution of this processor.
-lst.lookup = Look up an item/liquid/unit/block type by ID.\nTotal counts of each type can be accessed with:\n[accent]@unitCount[] / [accent]@itemCount[] / [accent]@liquidCount[] / [accent]@blockCount[]
+lst.lookup = Look up an item/liquid/unit/block type by ID.\nTotal counts of each type can be accessed with:\n[accent]@unitCount[] / [accent]@itemCount[] / [accent]@liquidCount[] / [accent]@blockCount[]\nFor the inverse operation, sense [accent]@id[] of the object.
 lst.jump = Conditionally jump to another statement.
 lst.unitbind = Bind to the next unit of a type, and store it in [accent]@unit[].
 lst.unitcontrol = Control the currently bound unit.
@@ -2275,6 +2275,7 @@ laccess.dead = Whether a unit/building is dead or no longer valid.
 laccess.controlled = Returns:\n[accent]@ctrlProcessor[] if unit controller is processor\n[accent]@ctrlPlayer[] if unit/building controller is player\n[accent]@ctrlCommand[] if unit controller is a player command\nOtherwise, 0.
 laccess.progress = Action progress, 0 to 1.\nReturns production, turret reload or construction progress.
 laccess.speed = Top speed of a unit, in tiles/sec.
+laccess.id = ID of a unit/block/item/liquid.\nThis is the inverse of the lookup operation.
 
 lcategory.unknown = Unknown
 lcategory.unknown.description = Uncategorized instructions.

core/src/mindustry/ctype/UnlockableContent.java

@@ -68,6 +68,10 @@ public abstract class UnlockableContent extends MappableContent{
         uiIcon = Core.atlas.find(getContentType().name() + "-" + name + "-ui", fullIcon);
     }
 
+    public int getLogicId(){
+        return logicVars.lookupLogicId(this);
+    }
+
     public String displayDescription(){
         return minfo.mod == null ? description : description + "\n" + Core.bundle.format("mod.display", minfo.mod.meta.displayName);
     }

core/src/mindustry/logic/LAccess.java

@@ -46,6 +46,7 @@ public enum LAccess{
     name,
     payloadCount,
     payloadType,
+    id,
 
     //values with parameters are considered controllable
     enabled("to"), //"to" is standard for single parameter access

core/src/mindustry/logic/LExecutor.java

@@ -1143,7 +1143,6 @@ public class LExecutor{
         }
     }
 
-    //TODO inverse lookup
     public static class LookupI implements LInstruction{
         public int dest;
         public int from;

core/src/mindustry/type/Item.java

@@ -153,8 +153,9 @@ public class Item extends UnlockableContent implements Senseable{
 
     @Override
     public double sense(LAccess sensor){
-        if(sensor == LAccess.color) return color.toFloatBits();
+        if(sensor == LAccess.color) return color.toDoubleBits();
-        return 0;
+        if(sensor == LAccess.id) return getLogicId();
+        return Float.NaN;
     }
 
     @Override

core/src/mindustry/type/Liquid.java

@@ -171,8 +171,9 @@ public class Liquid extends UnlockableContent implements Senseable{
 
     @Override
     public double sense(LAccess sensor){
-        if(sensor == LAccess.color) return color.toFloatBits();
+        if(sensor == LAccess.color) return color.toDoubleBits();
-        return 0;
+        if(sensor == LAccess.id) return getLogicId();
+        return Double.NaN;
     }
 
     @Override

core/src/mindustry/type/UnitType.java

@@ -28,6 +28,7 @@ import mindustry.game.*;
 import mindustry.gen.*;
 import mindustry.graphics.*;
 import mindustry.graphics.MultiPacker.*;
+import mindustry.logic.*;
 import mindustry.type.ammo.*;
 import mindustry.ui.*;
 import mindustry.world.*;
@@ -40,7 +41,7 @@ import mindustry.world.meta.*;
 import static arc.graphics.g2d.Draw.*;
 import static mindustry.Vars.*;
 
-public class UnitType extends UnlockableContent{
+public class UnitType extends UnlockableContent implements Senseable{
     public static final float shadowTX = -12, shadowTY = -13;
     private static final Vec2 legOffset = new Vec2();
 
@@ -1124,6 +1125,24 @@ public class UnitType extends UnlockableContent{
         return super.researchRequirements();
     }
 
+    @Override
+    public double sense(LAccess sensor){
+        return switch(sensor){
+            case health, maxHealth -> health;
+            case size -> hitSize / tilesize;
+            case itemCapacity -> itemCapacity;
+            case speed -> speed * 60f / tilesize;
+            case id -> getLogicId();
+            default -> Double.NaN;
+        };
+    }
+
+    @Override
+    public Object senseObject(LAccess sensor){
+        if(sensor == LAccess.name) return name;
+        return noSensed;
+    }
+
     @Override
     public ContentType getContentType(){
         return ContentType.unit;

core/src/mindustry/world/Block.java

@@ -1374,6 +1374,7 @@ public class Block extends UnlockableContent implements Senseable{
             case itemCapacity -> itemCapacity;
             case liquidCapacity -> liquidCapacity;
             case powerCapacity -> consPower != null && consPower.buffered ? consPower.capacity : 0f;
+            case id -> getLogicId();
             default -> Double.NaN;
         };
     }