Geometry and Drawing

Geometry and drawing

Oriented bounding boxes

An oriented bounding box stores a center, half-size extents, and rotation:

#include <DirectXCollision.h>
#include <CLibUtilsQTR/BoundingBox.hpp>

// With your engine PCH in scope:
bool ReadBounds(RE::TESObjectREFR* object,
                DirectX::BoundingOrientedBox& bounds) {
    return object && BoundingBox::GetOBB(object, bounds);
}

Use skyrim and provide DirectXMath/DirectXCollision headers in your build. The helper needs engine declarations from your PCH.

The reference overload derives bounds from the local bounds, scale, and world transform. Without current 3D it uses the reference's position and angles. False means useful bounds were not obtained.

The optional third argument is named allowAABB. When true, it first tries GetOBBFromHavok() before falling back to reference bounds. A separate GetOBB(RE::bhkRigidBody*, ...) uses the body's shape and transform; its default converts Havok units to Skyrim units.

ClosestPointOnOBB() can return an interior point. ClosestPointOnOBBSurface() finds a surface point. Both use a box you already obtained.

Diagnostic shapes

Once your plugin has an appropriate debug overlay running, enqueue a line:

#include <DirectXCollision.h>
#include <CLibUtilsQTR/DrawDebug.hpp>

constexpr int lifetimeMilliseconds = 1000;
DebugAPI_IMPL::DebugAPI::GetSingleton()->DrawLineForMS(
    from, to, lifetimeMilliseconds,
    DebugAPI_IMPL::DrawDebug::Colors::RED);

from and to are RE::NiPoint3 world positions. Circles and spheres are also available; DebugAPI_IMPL::DrawDebug contains capsule and oriented-box helpers.

This is existing overlay integration code, not a standalone renderer. DebugOverlayMenu currently uses movie path BetterThirdPersonSelection/overlay_menu and registers under "HUD Menu". The headers do not supply that movie. Account for those choices before installing an overlay; do not blindly register over an existing menu.

Register() registers and requests showing the menu. Its AdvanceMovie() calls DebugAPI::Update() to render and expire lines. Enqueuing lines alone does not create a working overlay. Show() and Hide() send menu messages.

Keep engine/UI operations in the appropriate game-thread lifecycle. Queue locking does not make arbitrary engine/UI access safe from workers.