Shadow list improvements (minetest#12898)

* Remove redundant checks when attaching SM texture to entities.
  Some of the checks were broken, leading to crashes when shadow intensity is set to 0
* Avoid memory leak in shadow casters list when wield mesh changes item stacks

src/client/shadows/dynamicshadowsrender.cpp

@@ -107,8 +107,7 @@ void ShadowRenderer::disable()
  }
 
  for (auto node : m_shadow_node_array)
- if (node.shadowMode & E_SHADOW_MODE::ESM_RECEIVE)
- node.node->setMaterialTexture(TEXTURE_LAYER_SHADOW, nullptr);
+ node.node->setMaterialTexture(TEXTURE_LAYER_SHADOW, nullptr);
 }
 
 void ShadowRenderer::initialize()
@@ -180,8 +179,7 @@ void ShadowRenderer::addNodeToShadowList(
  if (!node)
  return;
  m_shadow_node_array.emplace_back(node, shadowMode);
- if (shadowMode == ESM_RECEIVE || shadowMode == ESM_BOTH)
- node->setMaterialTexture(TEXTURE_LAYER_SHADOW, shadowMapTextureFinal);
+ node->setMaterialTexture(TEXTURE_LAYER_SHADOW, shadowMapTextureFinal);
 }
 
 void ShadowRenderer::removeNodeFromShadowList(scene::ISceneNode *node)
@@ -258,8 +256,7 @@ void ShadowRenderer::updateSMTextures()
  assert(shadowMapTextureFinal != nullptr);
 
  for (auto &node : m_shadow_node_array)
- if (node.shadowMode == ESM_RECEIVE || node.shadowMode == ESM_BOTH)
- node.node->setMaterialTexture(TEXTURE_LAYER_SHADOW, shadowMapTextureFinal);
+ node.node->setMaterialTexture(TEXTURE_LAYER_SHADOW, shadowMapTextureFinal);
  }
 
  if (!m_shadow_node_array.empty() && !m_light_list.empty()) {

src/client/wieldmesh.cpp

@@ -223,15 +223,20 @@ WieldMeshSceneNode::WieldMeshSceneNode(scene::ISceneManager *mgr, s32 id, bool l
  dummymesh->drop(); // m_meshnode grabbed it
 
  m_shadow = RenderingEngine::get_shadow_renderer();
+
+ if (m_shadow) {
+ // Add mesh to shadow caster
+ m_shadow->addNodeToShadowList(m_meshnode);
+ }
 }
 
 WieldMeshSceneNode::~WieldMeshSceneNode()
 {
  sanity_check(g_extrusion_mesh_cache);
 
  // Remove node from shadow casters. m_shadow might be an invalid pointer!
- if (auto shadow = RenderingEngine::get_shadow_renderer())
- shadow->removeNodeFromShadowList(m_meshnode);
+ if (m_shadow)
+ m_shadow->removeNodeFromShadowList(m_meshnode);
 
  if (g_extrusion_mesh_cache->drop())
  g_extrusion_mesh_cache = nullptr;
@@ -552,11 +557,6 @@ void WieldMeshSceneNode::changeToMesh(scene::IMesh *mesh)
  // need to normalize normals when lighting is enabled (because of setScale())
  m_meshnode->setMaterialFlag(video::EMF_NORMALIZE_NORMALS, m_lighting);
  m_meshnode->setVisible(true);
-
- if (m_shadow) {
- // Add mesh to shadow caster
- m_shadow->addNodeToShadowList(m_meshnode);
- }
 }
 
 void getItemMesh(Client *client, const ItemStack &item, ItemMesh *result)