def __init__(self):
Task.__init__(self)
# * Initialize variables
self.pointer = HapticPointer() # TODO create tools directly in Main, just like tasks, and find them here?
# * Load scene fragments
self.context.scene.readXML(self.context.getResourcePath('data', 'PointerScene.xml'))
class HapticSelectTask(Task):
"""Use a haptic pointing device to select interactive objects."""
feedback_gain = 0.5 # refer to OpenHaptics HLAPI docs (HL_EFFECT_PROPERTY_GAIN)
feedback_magnitude = 0.6 # strength of haptic feedback (HL_EFFECT_PROPERTY_MAGNITUDE)
def __init__(self):
Task.__init__(self)
# * Initialize variables
self.pointer = HapticPointer() # TODO create tools directly in Main, just like tasks, and find them here?
# * Load scene fragments
self.context.scene.readXML(self.context.getResourcePath('data', 'PointerScene.xml'))
# TODO Add proper pointer model, edit PointerScene.xml; move tool model loading to inside Tool classes?
def activate(self):
# * Find pointer actor in scene, reposition it and make it visible
self.pointerActor = self.context.scene.findActorById('pointer')
if self.pointerActor is None:
self.logger.warn("[HapticSelectTask] Pointer object not found in scene; task could not be initialized")
return
self.pointerActor.components['Transform'].translation = np.float32([0, 0, 80])
self.pointerActor.visible = True
Task.activate(self)
def deactivate(self):
Task.deactivate(self)
self.pointerActor.visible = False
self.pointer.close()
def update(self):
if self.pointer.valid:
# Update pointer actor's position and orientation in scene (TODO: transform coordinates to align reference frames so that pointer is physically and virtually co-located)
self.pointerActor.transform_matrix = self.pointer.transform # use transform directly
if True: # [debug: enables selection checking even when there is no valid haptic device connected - useful for development and testing, harmless when live]
# Check for collisions with Collider components
# TODO: Enhancements (mostly Collider improvements):
# 1. Generalize to other Collider types; currently supports SphereCollider only (and that too with radius correctly set)
# This will only be possible after certain improvements in the scene graph, esp. to query for actors with a certain base component (Collider)
# 2. Allow a single Collider to represent a whole hierarchy (if indicated), utilizing a bounding box for all meshes by default
# TODO: Optimizations:
# 1. Walk once when scene is finalized and cache all collidable actors, their colliders
# 2. Use a spatial index to speed up matching (otherwise this is very slow)
# * Walk the scene hierarchy looking for actors with Colliders
for actor in self.context.scene.findActorsByComponent('SphereCollider'):
try:
# ** Check if pointer is touching the actor, if so highlight it (also manage highlight removal)
dist = np.linalg.norm(actor.transform[:3, 3] - self.pointerActor.transform[:3, 3], ord=2)
isColliding = dist < actor.components['SphereCollider'].radius
#self.logger.debug("Actor: %s (%s), distance: %7.3f, colliding? %s", actor.id, actor.description, dist, isColliding) # [verbose]
if isColliding and not actor.components['SphereCollider'].isHighlighted:
actor.components['SphereCollider'].set_highlight(True)
self.logger.info("Touched %s (%s)! Distance: %.3f, time: %.3f", actor.id, actor.description, dist, self.context.timeNow) # [debug]
# Generate haptic feedback (TODO: vary magnitude by distance?)
self.pointer.setFeedback("on", self.feedback_gain, self.feedback_magnitude)
elif not isColliding and actor.components['SphereCollider'].isHighlighted:
actor.components['SphereCollider'].set_highlight(False)
self.pointer.setFeedback("off") # default off
except AttributeError as e:
self.logger.error("Couldn't compute distance to actor: %s", e)
