How 3D inspection works¶

Some objects are not picked up when you press the interact key. They open a screen where the object floats in front of you, lit and isolated, and you turn it in your hands before deciding what to do with it. That is inspection. The books, the notes and the trading cards that ship with the template all use it.

The prompt on those objects is the journal icon, because the base class ships with Use Icon on. Its Interact Text says Examine, and that word replaces the icon if you turn Use Icon off.

What the player does¶

Look at the object, press the interact key, and the inspect screen opens. From there:

Input	What it does
Left mouse button, held	Turn the object
Middle mouse button, held	Slide the object inside the frame
Mouse wheel	Zoom in and out
`IA_InspectAction1`	Run the `Primary` action, `E` by default
`IA_InspectAction2`	Run the `Secondary` action, `F` by default
`Escape`	Leave the inspect screen

The mouse and the exit key are plain Key fields on BP_PlayerInspectManager: Key Rotate, Key Pan, Key Zoom In, Key Zoom Out and Key Back. They do not go through Enhanced Input, so they do not appear in the rebinding list in the options menu.

The two action buttons do go through Enhanced Input. The component points at IA_InspectAction1 and IA_InspectAction2 through its IA Action 1 and IA Action 2 fields, and its Key Act 1 and Key Act 2 fields are left at None on purpose. Change those two keys in IMC_Default like any other, see Change the controls.

The pieces¶

Asset	What it is
`BP_Interactable_Pickup_InspectableBase`	The actor you place in the level. It is a normal pickup with physics, and it adds one field: `Inspect Data`.
`BP_InspectableDataAsset`, the `DA_Inspect_*` assets	What the object is. Name, mesh, start rotation, framing, and the list of actions.
`BP_PlayerInspectManager`	A component on the player. It opens and closes the screen, reads the mouse, and holds the feel settings.
`BP_InspectStage`	An actor that holds the inspected mesh, three lights and a scene capture.
`BP_InspectWidget`	The screen itself, with the object, its name and the two buttons.

The Data Assets live in Content/TheLastTemplate/Blueprints/DataAssets/Inspect/Childs/. BP_InspectStage and the action classes are in Content/TheLastTemplate/Blueprints/Inspect/. The pickup is in Content/TheLastTemplate/Blueprints/Environments/Interactable/Pickup/Inspect/, the component in Content/TheLastTemplate/Blueprints/ActorComponents/, and the two widgets in Content/TheLastTemplate/Blueprints/Widgets/Inspect/.

Only the three books have their own child class of the pickup. The notes and the cards are placed with BP_Interactable_Pickup_InspectableBase itself, with Inspect Data set on the placed actor. Both ways work, so make a child class only when you want the same object in several levels.

The stage is filmed, not the level¶

BP_InspectStage carries its own Item Mesh, its own Key Light, Fill Light and Rim Light, and a Scene Capture pointed at them. The capture writes into the render target Content/TheLastTemplate/Textures/Widgets/Inspect/RT_Inspect, which is 1600 by 900, and the material M_UI_InspectRT draws that render target on screen.

Nothing of the room the player is standing in reaches that image. An object looks the same at night in a basement as it does at noon outdoors, which is the point.

The consequence is that an inspectable object has two meshes, and they are two different fields:

Static Mesh on the pickup actor, the one lying in the level
Mesh on the DA_Inspect_* Data Asset, the one shown on the stage

They are normally the same asset, but nothing forces it. If the world shows a grey cube, Static Mesh was never set. If the inspect screen is empty, Mesh was never set.

Framing¶

Two fields on the Data Asset decide how the object presents itself.

Field	What it does	Shipped values
`Inspect Rotation`	The rotation the object opens at, before the player turns it	`0 / 90 / 90` on all eight shipped objects
`Frame Fill`	How much of the frame the object takes up. Raise it and the object comes closer	`0.75` on the three books, `0.82` on the notes and the cards

The camera itself is on the stage: Capture FOV is 32 and Capture Aspect is 1.7777778.

The two action slots¶

Every DA_Inspect_* has an Actions array of S_InspectActionEntry. Each entry is one button.

Field	What it does
`Action Class`	The `BP_InspectActionBase` child that runs when the button is pressed
`Slot`	`Primary` or `Secondary`, which is the `E` button or the `F` button
`Label`	The word written on the button, for example `Read` or `Take`
`Text Param`, `Text Lines`, `Float Param`, `Int Param`, `Class Param`	A parameter bag. Each action class reads only the ones it needs and ignores the rest
`Closes Inspect`	Whether running the action leaves the inspect screen

There are only the two slots, so a screen shows at most two buttons. A trading card ships with Read on Primary and Take on Secondary. DA_Inspect_Note_Sorry ships with Read alone.

These action classes ship, under Content/TheLastTemplate/Blueprints/Inspect/Actions/Childs/:

Class	What it does	What it needs
`BP_InspectAction_Read`	Shows a page of text over the object	`Text Param` as the title, `Text Lines` as the body, on the entry
`BP_InspectAction_TakeItem`	Takes the object as an inventory item	`Class Param` as the interactable to hand over, on the entry
`BP_InspectAction_TakeCollectible`	Takes the object as a collectible	Nothing on the entry
`BP_InspectAction_LearnRecipe`	Learns a crafting recipe	A child class with `Recipe to Learn` set
`BP_InspectAction_UnlockSkill`	Unlocks a player upgrade	A child class with `Skill to Unlock` and `Unlocked Levels` set

The last two ship with their target empty, so each object that uses them points at a child class instead. BP_InspectAction_LearnRecipe_Molotov is a child with Recipe to Learn set to DA_Recipe_Molotov, and BP_InspectAction_UnlockSkill_HealingPower is a child with Skill to Unlock set to DA_Skill_HealingPower and Unlocked Levels set to 3. Duplicate a child, change its target, and you have a new book.

BP_InspectActionBase also carries Hide When Blocked. When an action is not available, that boolean decides whether its button disappears or stays on screen. It is true on every action that ships.

Reading stays on the stage¶

Every shipped Read row sets Closes Inspect to false. Pressing the button opens BP_InspectReadWidget over the object instead of ending the inspection, so the player can read the note and then still press the other button. The shipped Take and Learn rows set Closes Inspect to true: once the object has given what it had, there is nothing left to look at.

Feel settings¶

All of these are on BP_PlayerInspectManager, on the player.

Field	Shipped value	Note
`Rotate Speed`	`0.9`	How fast the object follows the mouse
`Zoom Speed`	`0.14`	How much one wheel step moves the zoom
`Pan Speed`	`0.0035`	Much smaller than the other two. Panning is a nudge, not a move
`Zoom Min` / `Zoom Max`	`0` / `1`	Zoom is an amount between the two, not a distance
`Zoom Start`	`0`	The object opens at `Zoom Min`
`Invert Rotate X` / `Invert Rotate Y`	`false`	One axis each, so you can invert only one

Collectibles reuse the same thing¶

A collectible is a BP_CollectibleDataAsset with three fields: Display Name, Category and Inspect Data. It does not describe a mesh or a screen of its own, it points at a DA_Inspect_*. So a trading card is one inspectable object plus one line saying which shelf it belongs on, and the card is claimed by putting BP_InspectAction_TakeCollectible in the Secondary slot.

Join the Discord