/// <summary>
/// Sets the opacity (alpha) of a scene node - see remarks.
/// </summary>
/// <param name="node">The scene node.</param>
/// <param name="alpha">The alpha value.</param>
/// <remarks>
/// This method can be called for all types of <see cref="SceneNode"/>s. If the node is a
/// <see cref="MeshNode"/>, the method sets the
/// <see cref="DefaultEffectParameterSemantics.InstanceAlpha"/> effect parameter bindings in
/// the material instances. Currently, this method does nothing for all other types of scene
/// nodes.
/// </remarks>
/// <exception cref="ArgumentNullException">
/// <paramref name="node"/> is <see langword="null"/>.
/// </exception>
public static void SetInstanceAlpha(this SceneNode node, float alpha)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
// ReSharper disable CompareOfFloatsByEqualityOperator
if (alpha == 1)
{
// Abort if node's alpha is already equal to 1.
if (!node.GetFlag(SceneNodeFlags.IsAlphaSet))
{
return;
}
// Remember that node's alpha is reset to 1.
node.ClearFlag(SceneNodeFlags.IsAlphaSet);
}
else
{
// Remember that node's alpha is not 1.
node.SetFlag(SceneNodeFlags.IsAlphaSet);
}
// ReSharper restore CompareOfFloatsByEqualityOperator
// The only node which sets the HasAlpha flag is a MeshNode!
// Cast to MeshNode and update the InstanceAlpha parameter bindings.
// See also MeshNode.SetHasAlpha().
var meshNode = node as MeshNode;
if (meshNode != null)
{
foreach (var materialInstance in meshNode.MaterialInstances)
{
foreach (var effectBinding in materialInstance.EffectBindings)
{
foreach (var parameterBinding in effectBinding.ParameterBindings)
{
if (ReferenceEquals(parameterBinding.Description.Semantic, DefaultEffectParameterSemantics.InstanceAlpha))
{
var constParameterBinding = parameterBinding as ConstParameterBinding <float>;
if (constParameterBinding != null)
{
constParameterBinding.Value = alpha;
}
break;
}
}
}
}
}
}
/// <inheritdoc/>
public T Query <T>(SceneNode referenceNode, RenderContext context) where T : class, ISceneQuery, new()
{
if (referenceNode == null)
{
throw new ArgumentNullException("referenceNode");
}
// Use proxy node instead of specified node, if set.
while (referenceNode.Proxy != null)
{
referenceNode = referenceNode.Proxy;
}
// Check if the node was modified since Scene.Update(). This can happen, for
// example, if a CameraNode is rotated to capture 6 sides of a cube map.
if (referenceNode.GetFlag(SceneNodeFlags.IsDirtyScene))
{
// Reset all queries that use this node.
int numberOfQueries = _queries.Count;
for (int i = 0; i < numberOfQueries; i++)
{
if (_queries[i].ReferenceNode == referenceNode)
{
_queries[i].Reset();
}
}
referenceNode.ClearFlag(SceneNodeFlags.IsDirtyScene);
}
try
{
// ----- Get query of type T.
T query = null;
int numberOfQueries = _queries.Count;
for (int i = 0; i < numberOfQueries; i++)
{
query = _queries[i] as T;
if (query != null)
{
break;
}
}
if (query != null)
{
// Query exists.
// Return cached result if the reference node is the same.
if (query.ReferenceNode == referenceNode)
{
return(query);
}
}
else
{
// Create new query.
query = new T();
_queries.Add(query);
}
if (referenceNode.Shape is InfiniteShape)
{
// ----- Infinite shape queries.
// Return all scene nodes.
GetSceneNodes(this, referenceNode, _filter, _tempNodes);
query.Set(referenceNode, _tempNodes, context);
return(query);
}
// Add infinite nodes to temporary list.
foreach (var node in _infiniteNodes)
{
if (node.ActualIsEnabled && _filter.Filter(new Pair <SceneNode>(referenceNode, node)))
{
_tempNodes.Add(node);
}
}
var cameraNode = referenceNode as CameraNode;
if (cameraNode != null)
{
// ----- Camera frustum queries.
// Extract frustum planes.
Matrix44F viewProjection = cameraNode.Camera.Projection * cameraNode.View;
GeometryHelper.ExtractPlanes(viewProjection, _tempPlanes, false);
// Use broad phase to do frustum culling.
foreach (var collisionObject in ((DualPartition <CollisionObject>)_collisionDomain.BroadPhase).GetOverlaps(_tempPlanes))
{
// ISupportFrustumCulling.GetOverlaps() does not apply filtering.
// --> Manually check if collision object is enabled.
if (collisionObject.Enabled)
{
//if (collisionObject.GeometricObject.Shape is PlaneShape
// && !HaveAabbPlaneContact(referenceNode, collisionObject))
// continue;
var sceneNode = collisionObject.GeometricObject as SceneNode;
if (sceneNode != null && _filter.Filter(new Pair <SceneNode>(referenceNode, sceneNode)))
{
_tempNodes.Add(sceneNode);
}
}
}
}
else
{
// ----- Normal object queries.
var collisionObject = GetCollisionObject(referenceNode, false);
foreach (var contactSet in _collisionDomain.ContactSets.GetContacts(collisionObject))
{
SceneNode sceneNode;
if (contactSet.ObjectA == collisionObject)
{
sceneNode = contactSet.ObjectB.GeometricObject as SceneNode;
}
else
{
sceneNode = contactSet.ObjectA.GeometricObject as SceneNode;
}
Debug.Assert(sceneNode != null);
_tempNodes.Add(sceneNode);
}
}
query.Set(referenceNode, _tempNodes, context);
return(query);
}
finally
{
_tempPlanes.Clear();
_tempNodes.Clear();
}
}
