=== Motivation ===
The new drag & drop snapping helps easily & quickly placing objects in the scene. But it relies quite a bit on the asset and the scene it’s being dragged into (e.g. the size relative to the destination scene, the exact normal of the snapped to surface), etc. Users may want to adjust the rotation, the scale, the up-axis, use the origin for snapping rather than the bound-box (e.g. to place trees so they are partially covered by the ground plane), etc.
=== Basic Design Idea ===
Rather than setting these options before dragging (where you don’t get visual feedback) or while dragging (where it’s awkward to give input because you’re holding a mouse button), the Operate->Settings paradigm of Blender should be used: First the object/collection is dragged in and placed using basic snapping, then we provide a visual way to keep adjusting the transforms and parameters until the user is happy with the result.
However, this placement method isn't just useful for dragging in assets. It is useful as a general transform tool and should be created as such. So this is a proposal for a general placement tool with bounding-box or origin based surface snapping, that gives access to most important transforms and properties for placing an object. In some way or another, it could be (temporarily and optionally?) activated after dragging an object or collection asset into the scene. If more advanced transforms are needed, the user can still access the proper transform tools & operators.
=== Temporary Activation ===
Having to activate a placement tool every time an asset is dragged in can be annoying. Blender could automatically activate it, at least in some temporary fashion. For example, the tool could temporarily override the active tool after dragging in an asset. Deselecting the dragged in object would bring back the real active tool. If the user wishes to go back to the placement tool, that can be explicitly enabled again in the toolbar.
=== Tool Design ===
TODO