Deallocate removed pixels

Author: IntQuant

ewext/src/modules/world_sync.rs

@@ -125,9 +125,30 @@ impl WorldData for ParticleWorldState {
         for (i, pixel) in chunk.pixels.into_iter().enumerate() {
             let x = (i % CHUNK_SIZE) as isize;
             let y = (i / CHUNK_SIZE) as isize;
+
             let cell = pixel_array.get_mut_raw(shift_x + x, shift_y + y);
+
+            if !cell.is_null() {
+                let cell = unsafe { &**cell };
+                // Don't touch box2d stuff.
+                if cell.material.cell_type == CellType::Solid {
+                    continue;
+                }
+                // No point replacing cells with themselves.
+                if cell.material.material_type == pixel.mat() as isize {
+                    continue;
+                }
+            }
+
             let xs = start_x + x;
             let ys = start_y + y;
+            // Drop first
+            if !cell.is_null() {
+                unsafe {
+                    heap::delete(cell);
+                }
+                *cell = ptr::null_mut();
+            }
             if pixel.is_air() {
                 *cell = ptr::null_mut();
             } else {

noita_api/src/heap.rs

@@ -2,18 +2,18 @@ use std::sync::LazyLock;
 
 struct Msvcr {
     op_new: unsafe extern "C" fn(n: std::os::raw::c_uint) -> *mut std::os::raw::c_void,
-    // op_delete: unsafe extern "C" fn(*const std::os::raw::c_void),
+    op_delete: unsafe extern "C" fn(*const std::os::raw::c_void),
     // op_delete_array: unsafe extern "C" fn(*const std::os::raw::c_void),
 }
 
 static MSVCR: LazyLock<Msvcr> = LazyLock::new(|| unsafe {
     let lib = libloading::Library::new("./msvcr120.dll").expect("library to exist");
     let op_new = *lib.get(b"??2@YAPAXI@Z\0").expect("symbol to exist");
-    // let op_delete = *lib.get(b"operator_delete\0").expect("symbol to exist");
+    let op_delete = *lib.get(b"??3@YAXPAX@Z\0").expect("symbol to exist");
     // let op_delete_array = *lib.get(b"operator_delete[]\0").expect("symbol to exist");
     Msvcr {
         op_new,
-        // op_delete,
+        op_delete,
         // op_delete_array,
     }
 });
@@ -39,3 +39,10 @@ pub fn place_new<T>(value: T) -> *mut T {
 pub fn place_new_ref<T>(value: T) -> &'static mut T {
     unsafe { &mut *place_new(value) }
 }
+
+/// # Safety
+///
+/// Pointer has to be non null, allocated by noita's allocator, and not yet freed.
+pub unsafe fn delete<T>(pointer: *const T) {
+    unsafe { (MSVCR.op_delete)(pointer.cast()) }
+}

quant.ew/init.lua

@@ -22,7 +22,7 @@ net = dofile_once("mods/quant.ew/files/core/net.lua")
 inventory_helper = dofile_once("mods/quant.ew/files/core/inventory_helper.lua")
 player_fns = dofile_once("mods/quant.ew/files/core/player_fns.lua")
 
--- print("construct_cell", np.GetWorldInfo().construct_cell)
+-- print("construct_cell", np.GetWorldInfo().remove_cell)
 
 local cos = dofile_once("mods/quant.ew/files/system/player/player_cosmetics.lua")