--- a/src/semicongine/engine.nim	Sun Sep 24 21:34:17 2023 +0700
+++ b/src/semicongine/engine.nim	Sun Sep 24 23:15:08 2023 +0700
@@ -113,12 +113,16 @@
 proc initRenderer*(engine: var Engine, clearColor=Vec4f([0.8'f32, 0.8'f32, 0.8'f32, 1'f32])) =
   engine.initRenderer(@[], clearColor)
 
-proc addScene*(engine: var Engine, scene: var Scene) =
+proc loadScene*(engine: var Engine, scene: var Scene) =
   assert engine.renderer.isSome
+  assert not scene.loaded
   engine.renderer.get.setupDrawableBuffers(scene)
   engine.renderer.get.updateMeshData(scene, forceAll=true)
   engine.renderer.get.updateUniformData(scene, forceAll=true)
 
+proc unloadScene*(engine: var Engine, scene: Scene) =
+  engine.renderer.get.destroy(scene)
+
 proc renderScene*(engine: var Engine, scene: var Scene) =
   assert engine.state == Running
   assert engine.renderer.isSome

--- a/src/semicongine/renderer.nim	Sun Sep 24 21:34:17 2023 +0700
+++ b/src/semicongine/renderer.nim	Sun Sep 24 23:15:08 2023 +0700
@@ -452,6 +452,25 @@
 func valid*(renderer: Renderer): bool =
   renderer.device.vk.valid
 
+proc destroy*(renderer: var Renderer, scene: Scene) =
+  var scenedata = renderer.scenedata[scene]
+
+  for buffer in scenedata.vertexBuffers.mvalues:
+    assert buffer.vk.valid
+    buffer.destroy()
+  if scenedata.indexBuffer.vk.valid:
+    assert scenedata.indexBuffer.vk.valid
+    scenedata.indexBuffer.destroy()
+  for pipelineUniforms in scenedata.uniformBuffers.mvalues:
+    for buffer in pipelineUniforms.mitems:
+      assert buffer.vk.valid
+      buffer.destroy()
+  for textures in scenedata.textures.mvalues:
+    for texture in textures.mitems:
+      texture.destroy()
+  for descriptorPool in scenedata.descriptorPools.mvalues:
+    descriptorPool.destroy()
+
 proc destroy*(renderer: var Renderer) =
   for scenedata in renderer.scenedata.mvalues:
     for buffer in scenedata.vertexBuffers.mvalues:

--- a/src/semicongine/scene.nim	Sun Sep 24 21:34:17 2023 +0700
+++ b/src/semicongine/scene.nim	Sun Sep 24 23:15:08 2023 +0700
@@ -1,5 +1,6 @@
 import std/tables
 import std/sequtils
+import std/strformat
 import std/hashes
 
 import ./core
@@ -11,18 +12,22 @@
     shaderGlobals*: Table[string, DataList]
     meshes*: seq[Mesh]
     dirtyShaderGlobals: seq[string]
+    loaded*: bool = false
 
 proc add*(scene: var Scene, mesh: MeshObject) =
+  assert not scene.loaded, &"Scene {scene.name} has already been loaded, cannot add meshes"
   var tmp = new Mesh
   tmp[] = mesh
   scene.meshes.add tmp
 
 proc add*(scene: var Scene, mesh: Mesh) =
+  assert not scene.loaded, &"Scene {scene.name} has already been loaded, cannot add meshes"
   assert not mesh.isNil, "Cannot add a mesh that is 'nil'"
   scene.meshes.add mesh
 
 # generic way to add objects that have a mesh-attribute
 proc add*[T](scene: var Scene, obj: T) =
+  assert not scene.loaded, &"Scene {scene.name} has already been loaded, cannot add meshes"
   for name, value in obj.fieldPairs:
     when typeof(value) is Mesh:
       assert not value.isNil, "Cannot add a mesh that is 'nil': " & name
@@ -32,11 +37,13 @@
       scene.meshes.add value
 
 proc addShaderGlobal*[T](scene: var Scene, name: string, data: T) =
+  assert not scene.loaded, &"Scene {scene.name} has already been loaded, cannot add shader values"
   scene.shaderGlobals[name] = newDataList(thetype=getDataType[T]())
   setValues(scene.shaderGlobals[name], @[data])
   scene.dirtyShaderGlobals.add name
 
 proc addShaderGlobalArray*[T](scene: var Scene, name: string, data: openArray[T]) =
+  assert not scene.loaded, &"Scene {scene.name} has already been loaded, cannot add shader values"
   scene.shaderGlobals[name] = newDataList(data)
   scene.dirtyShaderGlobals.add name
 
@@ -56,11 +63,6 @@
   if not scene.dirtyShaderGlobals.contains(name):
     scene.dirtyShaderGlobals.add name
 
-func appendShaderGlobalArray*[T](scene: var Scene, name: string, value: seq[T]) =
-  appendValues[T](scene.shaderGlobals[name], value)
-  if not scene.dirtyShaderGlobals.contains(name):
-    scene.dirtyShaderGlobals.add name
-
 func dirtyShaderGlobals*(scene: Scene): seq[string] =
   scene.dirtyShaderGlobals