Mouse Pick

Type: Action (branch)
Category: RAYCAST

Casts a ray from the active camera through the mouse cursor position. Ideal for 3D object selection, point-and-click targeting, and interaction systems.

Properties

Property	Type	Default	Description
Ray ID	String	"mpick"	Shared identifier with Raycast Result
Distance	Float	100.0	Maximum ray length
Prop Filter	String	""	Only hit objects with this BGE property

Sockets

Socket	Direction	Type
In	Input	Exec
Hit	Output	Exec
Miss	Output	Exec

Generated code

_mp_cam  = self.own.scene.active_camera
_mp_mpos = Range.logic.mouse.position
_mp_vec  = _mp_cam.getScreenVect(_mp_mpos[0], _mp_mpos[1])
_mp_orig = _mp_cam.worldPosition.copy()
_mp_to   = _mp_orig - _mp_vec * 100.0
_mp_res  = _mp_cam.rayCast(_mp_to, _mp_orig, 100.0, '', 0, 0, 0)
self._rc_mpick_hit = _mp_res[0]
self._rc_mpick_pos = list(_mp_res[1]) if _mp_res[1] else [0.0, 0.0, 0.0]
self._rc_mpick_nrm = list(_mp_res[2]) if _mp_res[2] else [0.0, 0.0, 1.0]
if _mp_res[0] is not None:
    # Hit branch
else:
    # Miss branch

Typical usage

Highlight object under cursor

[On Update]
    → [Mouse Pick: Distance=50.0, Ray ID="hover"]
          └── Hit  ──► [BTCustomTask:
                            _hit = getattr(self, '_rc_hover_hit', None)
                            if _hit: _hit['highlighted'] = True]
          └── Miss ──► [...]

Place object at click point

[On Mouse Button: Button=LEFT, Mode=PRESSED]
    → [Mouse Pick: Distance=200.0, Prop Filter="terrain", Ray ID="place"]
          └── Hit  ──► [Add Object:
                           Object="building"
                           X={Raycast Result: Ray ID="place", Result=Hit Pos X}
                           Y={Raycast Result: Ray ID="place", Result=Hit Pos Y}
                           Z={Raycast Result: Ray ID="place", Result=Hit Pos Z}]
          └── Miss ──► [...]

Notes

• The ray is cast from scene.active_camera, not from the object that holds the component.
• Results stored in self._rc_<ID>_hit/pos/nrm, same as all other raycast nodes.
• Use Raycast Result with the same Ray ID to read name, position and normal.
• Combine with Prop Filter to detect only specific object types (terrain, enemies, etc.).