resource: add missing resource existence checks

src/resource/unit_compiler.cpp

@@ -124,6 +124,13 @@ static Buffer compile_mesh_renderer(const char* json, CompileOptions& opts)
 		, opts
 		);
 
+	DynamicString material(ta);
+	sjson::parse_string(obj["material"], material);
+	DATA_COMPILER_ASSERT_RESOURCE_EXISTS("material"
+		, material.c_str()
+		, opts
+		);
+
 	MeshRendererDesc mrd;
 	mrd.mesh_resource     = sjson::parse_resource_id(obj["mesh_resource"]);
 	mrd.geometry_name     = sjson::parse_string_id  (obj["geometry_name"]);
@@ -151,6 +158,13 @@ static Buffer compile_sprite_renderer(const char* json, CompileOptions& opts)
 		, opts
 		);
 
+	DynamicString material(ta);
+	sjson::parse_string(obj["material"], material);
+	DATA_COMPILER_ASSERT_RESOURCE_EXISTS("material"
+		, material.c_str()
+		, opts
+		);
+
 	SpriteRendererDesc srd;
 	srd.sprite_resource   = sjson::parse_resource_id(obj["sprite_resource"]);
 	srd.material_resource = sjson::parse_resource_id(obj["material"]);