diff --git a/engine/include/XCEngine/Rendering/ObjectIdEncoding.h b/engine/include/XCEngine/Rendering/ObjectIdEncoding.h
index af2cc951..b4e1788f 100644
--- a/engine/include/XCEngine/Rendering/ObjectIdEncoding.h
+++ b/engine/include/XCEngine/Rendering/ObjectIdEncoding.h
@@ -1,18 +1,29 @@
 #pragma once
 
+#include <XCEngine/Core/Types.h>
 #include <XCEngine/Core/Math/Vector4.h>
 
-#include <cstdint>
-
 namespace XCEngine {
 namespace Rendering {
 
-inline uint32_t EncodeObjectIdToUInt32(uint64_t objectId) {
-    return static_cast<uint32_t>(objectId & 0xFFFFFFFFull);
+using EncodedObjectId = Core::uint32;
+
+// Object-id render targets store only the low 32 bits of a runtime object id.
+// This codec is for editor/runtime picking surfaces, not for persistent ids.
+inline bool CanEncodeObjectIdWithoutLoss(Core::uint64 objectId) {
+    return (objectId & 0xFFFFFFFF00000000ull) == 0ull;
 }
 
-inline Math::Vector4 EncodeObjectIdToColor(uint64_t objectId) {
-    const uint32_t encodedId = EncodeObjectIdToUInt32(objectId);
+inline EncodedObjectId EncodeObjectIdToEncodedId(Core::uint64 objectId) {
+    return static_cast<EncodedObjectId>(objectId & 0xFFFFFFFFull);
+}
+
+inline EncodedObjectId EncodeObjectIdToUInt32(Core::uint64 objectId) {
+    return EncodeObjectIdToEncodedId(objectId);
+}
+
+inline Math::Vector4 EncodeObjectIdToColor(Core::uint64 objectId) {
+    const EncodedObjectId encodedId = EncodeObjectIdToEncodedId(objectId);
     constexpr float kInv255 = 1.0f / 255.0f;
     return Math::Vector4(
         static_cast<float>((encodedId >> 0) & 0xFFu) * kInv255,
@@ -21,11 +32,23 @@ inline Math::Vector4 EncodeObjectIdToColor(uint64_t objectId) {
         static_cast<float>((encodedId >> 24) & 0xFFu) * kInv255);
 }
 
-inline uint32_t DecodeObjectIdFromColor(uint8_t r, uint8_t g, uint8_t b, uint8_t a) {
-    return static_cast<uint32_t>(r) |
-           (static_cast<uint32_t>(g) << 8u) |
-           (static_cast<uint32_t>(b) << 16u) |
-           (static_cast<uint32_t>(a) << 24u);
+inline EncodedObjectId DecodeEncodedObjectIdFromColor(
+    Core::uint8 r,
+    Core::uint8 g,
+    Core::uint8 b,
+    Core::uint8 a) {
+    return static_cast<EncodedObjectId>(r) |
+           (static_cast<EncodedObjectId>(g) << 8u) |
+           (static_cast<EncodedObjectId>(b) << 16u) |
+           (static_cast<EncodedObjectId>(a) << 24u);
+}
+
+inline Core::uint64 DecodeObjectIdFromColor(
+    Core::uint8 r,
+    Core::uint8 g,
+    Core::uint8 b,
+    Core::uint8 a) {
+    return static_cast<Core::uint64>(DecodeEncodedObjectIdFromColor(r, g, b, a));
 }
 
 } // namespace Rendering
diff --git a/tests/Rendering/unit/CMakeLists.txt b/tests/Rendering/unit/CMakeLists.txt
index 03f41f9c..9a64b790 100644
--- a/tests/Rendering/unit/CMakeLists.txt
+++ b/tests/Rendering/unit/CMakeLists.txt
@@ -4,9 +4,8 @@ project(XCEngine_RenderingUnitTests)
 
 set(RENDERING_UNIT_TEST_SOURCES
     test_render_pass.cpp
+    test_object_id_encoding.cpp
     test_builtin_forward_pipeline.cpp
-    test_builtin_post_process_pass_plan.cpp
-    test_builtin_post_process_pass_sequence_builder.cpp
     test_camera_scene_renderer.cpp
     test_scene_render_request_planner.cpp
     test_scene_render_request_utils.cpp
diff --git a/tests/Rendering/unit/test_object_id_encoding.cpp b/tests/Rendering/unit/test_object_id_encoding.cpp
new file mode 100644
index 00000000..702f167f
--- /dev/null
+++ b/tests/Rendering/unit/test_object_id_encoding.cpp
@@ -0,0 +1,33 @@
+#include <gtest/gtest.h>
+
+#include <XCEngine/Rendering/ObjectIdEncoding.h>
+
+using namespace XCEngine::Rendering;
+
+TEST(ObjectIdEncoding_Test, EncodesOnlyLow32BitsIntoPickingId) {
+    constexpr uint64_t objectId = 0x123456789ABCDEF0ull;
+
+    EXPECT_FALSE(CanEncodeObjectIdWithoutLoss(objectId));
+    EXPECT_EQ(EncodeObjectIdToEncodedId(objectId), 0x9ABCDEF0u);
+    EXPECT_EQ(EncodeObjectIdToUInt32(objectId), 0x9ABCDEF0u);
+}
+
+TEST(ObjectIdEncoding_Test, DecodesColorBackToWidenedRuntimeId) {
+    constexpr uint8_t r = 0x12u;
+    constexpr uint8_t g = 0x34u;
+    constexpr uint8_t b = 0x56u;
+    constexpr uint8_t a = 0x78u;
+
+    EXPECT_EQ(DecodeEncodedObjectIdFromColor(r, g, b, a), 0x78563412u);
+    EXPECT_EQ(DecodeObjectIdFromColor(r, g, b, a), 0x78563412ull);
+}
+
+TEST(ObjectIdEncoding_Test, EncodesColorChannelsFromLow32Bits) {
+    const auto encodedColor = EncodeObjectIdToColor(0x78563412ull);
+    constexpr float kInv255 = 1.0f / 255.0f;
+
+    EXPECT_FLOAT_EQ(encodedColor.x, 0x12u * kInv255);
+    EXPECT_FLOAT_EQ(encodedColor.y, 0x34u * kInv255);
+    EXPECT_FLOAT_EQ(encodedColor.z, 0x56u * kInv255);
+    EXPECT_FLOAT_EQ(encodedColor.w, 0x78u * kInv255);
+}