Formalize scene viewport interaction resolver

tests/editor/CMakeLists.txt

@@ -11,6 +11,7 @@ set(EDITOR_TEST_SOURCES
     test_scene_viewport_rotate_gizmo.cpp
     test_scene_viewport_scale_gizmo.cpp
     test_scene_viewport_picker.cpp
+    test_scene_viewport_interaction_resolver.cpp
     test_scene_viewport_shader_paths.cpp
     test_scene_viewport_overlay_renderer.cpp
     test_scene_viewport_overlay_providers.cpp
@@ -38,6 +39,7 @@ set(EDITOR_TEST_SOURCES
     ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportRotateGizmo.cpp
     ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportScaleGizmo.cpp
     ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportHudOverlay.cpp
+    ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportInteractionResolver.cpp
     ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportOrientationGizmo.cpp
     ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportOverlayBuilder.cpp
     ${CMAKE_SOURCE_DIR}/editor/src/Viewport/SceneViewportOverlayProviders.cpp

tests/editor/test_scene_viewport_interaction_resolver.cpp

@@ -0,0 +1,90 @@
+#include <gtest/gtest.h>
+
+#include "Viewport/SceneViewportInteractionResolver.h"
+
+using XCEngine::Editor::ResolveSceneViewportInteraction;
+using XCEngine::Editor::SceneViewportGizmoAxis;
+using XCEngine::Editor::SceneViewportHudOverlayHitKind;
+using XCEngine::Editor::SceneViewportHudOverlayHitResult;
+using XCEngine::Editor::SceneViewportInteractionKind;
+using XCEngine::Editor::SceneViewportInteractionResolveRequest;
+using XCEngine::Editor::SceneViewportOrientationAxis;
+using XCEngine::Editor::SceneViewportOverlayFrameData;
+using XCEngine::Editor::SceneViewportOverlayHandleHitResult;
+using XCEngine::Editor::SceneViewportOverlayHandleKind;
+using XCEngine::Editor::SceneViewportOverlayHandleRecord;
+using XCEngine::Editor::SceneViewportOverlayHandleShape;
+using XCEngine::Math::Vector2;
+
+TEST(SceneViewportInteractionResolverTest, ReturnsNoHitWhenBothSourcesAreEmpty) {
+    const auto interaction = ResolveSceneViewportInteraction(
+        SceneViewportOverlayHandleHitResult{},
+        SceneViewportHudOverlayHitResult{});
+
+    EXPECT_FALSE(interaction.HasHit());
+    EXPECT_EQ(interaction.kind, SceneViewportInteractionKind::None);
+}
+
+TEST(SceneViewportInteractionResolverTest, PrefersTransformHandleOverHudOrientationByPriority) {
+    SceneViewportOverlayHandleHitResult overlayHandleHit = {};
+    overlayHandleHit.kind = SceneViewportOverlayHandleKind::MoveAxis;
+    overlayHandleHit.handleId = static_cast<uint64_t>(SceneViewportGizmoAxis::X);
+    overlayHandleHit.priority = 322;
+    overlayHandleHit.distanceSq = 4.0f;
+    overlayHandleHit.depth = 3.0f;
+
+    SceneViewportHudOverlayHitResult hudHit = {};
+    hudHit.kind = SceneViewportHudOverlayHitKind::OrientationAxis;
+    hudHit.orientationAxis = SceneViewportOrientationAxis::PositiveX;
+
+    const auto interaction = ResolveSceneViewportInteraction(overlayHandleHit, hudHit);
+
+    ASSERT_TRUE(interaction.HasHit());
+    EXPECT_EQ(interaction.kind, SceneViewportInteractionKind::MoveGizmo);
+    EXPECT_EQ(interaction.moveAxis, SceneViewportGizmoAxis::X);
+    EXPECT_EQ(interaction.orientationAxis, SceneViewportOrientationAxis::None);
+}
+
+TEST(SceneViewportInteractionResolverTest, PrefersHudOrientationOverSceneIconByPriority) {
+    SceneViewportOverlayHandleHitResult overlayHandleHit = {};
+    overlayHandleHit.kind = SceneViewportOverlayHandleKind::SceneIcon;
+    overlayHandleHit.entityId = 99;
+    overlayHandleHit.priority = 100;
+    overlayHandleHit.distanceSq = 0.0f;
+    overlayHandleHit.depth = 0.0f;
+
+    SceneViewportHudOverlayHitResult hudHit = {};
+    hudHit.kind = SceneViewportHudOverlayHitKind::OrientationAxis;
+    hudHit.orientationAxis = SceneViewportOrientationAxis::PositiveY;
+
+    const auto interaction = ResolveSceneViewportInteraction(overlayHandleHit, hudHit);
+
+    ASSERT_TRUE(interaction.HasHit());
+    EXPECT_EQ(interaction.kind, SceneViewportInteractionKind::OrientationGizmo);
+    EXPECT_EQ(interaction.orientationAxis, SceneViewportOrientationAxis::PositiveY);
+    EXPECT_EQ(interaction.entityId, 0u);
+}
+
+TEST(SceneViewportInteractionResolverTest, RequestPathDelegatesToOverlayHandleHitTesting) {
+    SceneViewportOverlayFrameData frameData = {};
+    frameData.overlay.valid = true;
+
+    SceneViewportOverlayHandleRecord& record = frameData.handleRecords.emplace_back();
+    record.kind = SceneViewportOverlayHandleKind::SceneIcon;
+    record.entityId = 77;
+    record.shape = SceneViewportOverlayHandleShape::ScreenRect;
+    record.priority = 100;
+    record.screenCenter = Vector2(80.0f, 60.0f);
+    record.screenHalfSize = Vector2(12.0f, 10.0f);
+
+    SceneViewportInteractionResolveRequest request = {};
+    request.overlayFrameData = &frameData;
+    request.viewportSize = Vector2(200.0f, 150.0f);
+    request.localMousePosition = Vector2(80.0f, 60.0f);
+
+    const auto interaction = ResolveSceneViewportInteraction(request);
+
+    ASSERT_TRUE(interaction.HasHit());
+    EXPECT_EQ(interaction.kind, SceneViewportInteractionKind::SceneIcon);
+    EXPECT_EQ(interaction.entityId, 77u);
+}