Fixed #4694

core/src/mindustry/core/Renderer.java

@@ -208,7 +208,7 @@ public class Renderer implements ApplicationListener{
         Draw.draw(Layer.background, this::drawBackground);
         Draw.draw(Layer.floor, blocks.floor::drawFloor);
         Draw.draw(Layer.block - 1, blocks::drawShadows);
-        Draw.draw(Layer.block, () -> {
+        Draw.draw(Layer.block - 0.09f, () -> {
             blocks.floor.beginDraw();
             blocks.floor.drawLayer(CacheLayer.walls);
             blocks.floor.endDraw();

core/src/mindustry/graphics/FloorRenderer.java

@@ -119,6 +119,7 @@ public class FloorRenderer implements Disposable{
             return;
         }
 
+        Draw.flush();
         cbatch.setProjection(Core.camera.mat);
         cbatch.beginDraw();
 

core/src/mindustry/input/Placement.java

@@ -100,7 +100,7 @@ public class Placement{
             i ++;
         }
 
-        if(!addedLast) result.add(base.peek());
+        if(!addedLast && !base.isEmpty()) result.add(base.peek());
 
         points.clear();
         points.addAll(result);