Class TShape

Unit

Declaration

type TShape = class(TShapeTree)

Description

Shape is a geometry node Geometry instance and it's State. For VRML >= 2.0, this usually corresponds to a single instance of actual VRML Shape node. It allows to perform many operations that need to know both geometry and it's current state (parent Shape node, current transformation and such).

This class caches results of methods LocalBoundingBox, BoundingBox, and most others (see TShapeValidities for hints). This means that things work fast, but this also means that you must manually call Changed when you changed some properties of Geometry or contents of State.

But note that you can't change Geometry or State to different objects — they are readonly properties.

Also note that if you're using TCastleSceneCore class then you don't have to worry about calling Changed of items in TCastleSceneCore.Shapes. All you have to do is to call appropriate Changed* methods of TCastleSceneCore.

Hierarchy

Overview

Nested Types

Published TNormalsCached = (...);

Methods

Public constructor Create(const AParentScene: TX3DEventsEngine; const AOriginalGeometry: TAbstractGeometryNode; const AOriginalState: TX3DGraphTraverseState; const ParentInfo: PTraversingInfo);
Public destructor Destroy; override;
Public function Geometry: TAbstractGeometryNode;
Public function State: TX3DGraphTraverseState;
Public function LocalBoundingBox: TBox3D;
Public function BoundingBox: TBox3D;
Public function VerticesCount: Cardinal; overload;
Public function TrianglesCount: Cardinal; overload;
Public function VerticesCount(const Ignored: Boolean): Cardinal; overload; deprecated 'use VerticesCount without Boolean argument, it is ignored now';
Public function TrianglesCount(const Ignored: Boolean): Cardinal; overload; deprecated 'use TrianglesCount without Boolean argument, it is ignored now';
Public function GeometryArrays: TGeometryArrays;
Public function BoundingSphereCenter: TVector3;
Public function BoundingSphereRadiusSqr: Single;
Public function BoundingSphereRadius: Single;
Public function FrustumBoundingSphereCollisionPossible( const Frustum: TFrustum): TFrustumCollisionPossible;
Public function FrustumBoundingSphereCollisionPossibleSimple( const Frustum: TFrustum): boolean;
Public procedure Changed(const InactiveOnly: boolean; const Changes: TX3DChanges); virtual;
Public function InternalOctreeTriangles: TTriangleOctree;
Public function InternalTriangleOctreeLimits: POctreeLimits;
Public function AlphaChannel: TAlphaChannel;
Public function Blending: boolean; deprecated 'use "AlphaChannel = acBlending"';
Public function Transparent: boolean; deprecated 'use "AlphaChannel = acBlending"';
Public function Visible: boolean;
Public function Collidable: boolean;
Public function RayCollision( const Tag: TMailboxTag; out Intersection: TVector3; out IntersectionDistance: Single; const RayOrigin, RayDirection: TVector3; const ReturnClosestIntersection: boolean; const TriangleToIgnore: PTriangle; const IgnoreMarginAtStart: boolean; const TrianglesToIgnoreFunc: TTriangleIgnoreFunc): PTriangle;
Public function SegmentCollision( const Tag: TMailboxTag; out Intersection: TVector3; out IntersectionDistance: Single; const Pos1, Pos2: TVector3; const ReturnClosestIntersection: boolean; const TriangleToIgnore: PTriangle; const IgnoreMarginAtStart: boolean; const TrianglesToIgnoreFunc: TTriangleIgnoreFunc): PTriangle;
Public function NormalsSmooth(const FromCcw: boolean): TVector3List;
Public function NormalsFlat(const FromCcw: boolean): TVector3List;
Public function NormalsCreaseAngle(const FromCcw: boolean; const CreaseAngle: Single): TVector3List;
Public function EnumerateTextures(const Enumerate: TEnumerateShapeTexturesFunction): Pointer; override;
Public function UsesTexture(Node: TAbstractTextureNode): boolean;
Public function ShadowCaster: boolean;
Public procedure Triangulate(const TriangleEvent: TTriangleEvent);
Public procedure LocalTriangulate(const TriangleEvent: TTriangleEvent);
Public function DebugInfo(const Indent: string = ''): string; override;
Public function NiceName: string;
Public function Node: TAbstractShapeNode;
Public function GeometryParentNodeName: String; deprecated 'use GeometryParentNode.X3DName';
Public function GeometryGrandParentNodeName: String; deprecated 'use GeometryGrandParentNode.X3DName';
Public function GeometryGrandGrandParentNodeName: String; deprecated 'use GeometryGrandGrandParentNode.X3DName';
Public function InternalMaterialProperty: TMaterialProperty;
Public function MaterialProperty: TMaterialProperty; deprecated 'use InternalMaterialProperty, or (better) do not use it at all -- this is internal';

Properties

Public property OriginalGeometry: TAbstractGeometryNode read FOriginalGeometry;
Public property OriginalState: TX3DGraphTraverseState read FOriginalState;
Public property InternalSpatial: TShapeSpatialStructures read FSpatial write SetSpatial;
Public property InternalTriangleOctreeProgressTitle: string read FTriangleOctreeProgressTitle write FTriangleOctreeProgressTitle;
Public property DynamicGeometry: Boolean read FDynamicGeometry;
Public property GeometryParentNode: TX3DNode read FGeometryParentNode;
Public property GeometryGrandParentNode: TX3DNode read FGeometryGrandParentNode;
Public property GeometryGrandGrandParentNode: TX3DNode read FGeometryGrandGrandParentNode;

Description

Nested Types

Published TNormalsCached = (...);
 
Values
  • ncSmooth
  • ncFlat
  • ncCreaseAngle

Methods

Public constructor Create(const AParentScene: TX3DEventsEngine; const AOriginalGeometry: TAbstractGeometryNode; const AOriginalState: TX3DGraphTraverseState; const ParentInfo: PTraversingInfo);

Constructor.

Parameters
ParentInfo
Recursive information about parents, for the geometry node of given shape. Note that for VRML 2.0/X3D, the immediate parent of geometry node is always TShapeNode.
Public destructor Destroy; override;
 
Public function Geometry: TAbstractGeometryNode;

Geometry of this shape. This may come from initial VRML/X3D node graph (see OriginalGeometry), or it may be processed by TAbstractGeometryNode.Proxy for easier handling.

Public function State: TX3DGraphTraverseState;

State of this shape. This may come from initial VRML/X3D node graph (see OriginalState), or it may be processed by TAbstractGeometryNode.Proxy for easier handling.

Owned by this TShape class.

Public function LocalBoundingBox: TBox3D;

Bounding box in local shape coordinates, i.e. disregarging all transformations (any TTransformNode, TCastleTransform) done on top of shape.

Public function BoundingBox: TBox3D;

Bounding box in scene coordinates, i.e. in the local coordinates of TCastleSceneCore that owns this shape.

The idea is that TCastleSceneCore.LocalBoundingBox is calculated just by summing up the Shape.BoundingBox for each shape. So transformations done using TTransformNode are accounted here. Parent TCastleTransform are not accounted here.

Public function VerticesCount: Cardinal; overload;
 
Public function TrianglesCount: Cardinal; overload;
 
Public function VerticesCount(const Ignored: Boolean): Cardinal; overload; deprecated 'use VerticesCount without Boolean argument, it is ignored now';

Warning: this symbol is deprecated: use VerticesCount without Boolean argument, it is ignored now

 
Public function TrianglesCount(const Ignored: Boolean): Cardinal; overload; deprecated 'use TrianglesCount without Boolean argument, it is ignored now';

Warning: this symbol is deprecated: use TrianglesCount without Boolean argument, it is ignored now

 
Public function GeometryArrays: TGeometryArrays;

Decompose the geometry into primitives, with arrays of per-vertex data.

Public function BoundingSphereCenter: TVector3;

Calculates bounding sphere based on BoundingBox. In the future this may be changed to use BoundingSphere method of TAbstractGeometryNode, when I will implement it. For now, BoundingSphere is always worse approximation of bounding volume than BoundingBox (i.e. BoundingSphere is always larger) but it may be useful in some cases when detecting collision versus bounding sphere is much faster than detecting them versus bounding box.

BoundingSphereRadiusSqr = 0 and BoundingSphereCenter is undefined if Box is empty.

Public function BoundingSphereRadiusSqr: Single;
 
Public function BoundingSphereRadius: Single;
 
Public function FrustumBoundingSphereCollisionPossible( const Frustum: TFrustum): TFrustumCollisionPossible;

Exactly equivalent to getting BoundingSphereCenter and BoundingSphereRadiusSqr and then using TFrustum.SphereCollisionPossible.

But it may be a little faster since it avoids some small speed problems (like copying memory contents when you get values of BoundingSphereXxx properties and checking twice are BoundingSphereXxx calculated).

Public function FrustumBoundingSphereCollisionPossibleSimple( const Frustum: TFrustum): boolean;

Exactly equivalent to getting BoundingSphereCenter and BoundingSphereRadiusSqr and then using TFrustum.SphereCollisionPossibleSimple.

But it may be a little faster since it avoids some small speed problems.

Public procedure Changed(const InactiveOnly: boolean; const Changes: TX3DChanges); virtual;

Notify this shape that you changed a field inside one of it's nodes (automatically done by TCastleSceneCore). This should be called when fields within Shape.Geometry, Shape.State.Last*, Shape.State.ShapeNode or such change.

Pass InactiveOnly = True is you know that this shape is fully in inactive X3D graph part (inactive Switch, LOD etc. children).

Including chTransform in Changes means something more than general chTransform (which means that transformation of children changed, which implicates many things — not only shape changes). Here, chTransform in Changes means that only the transformation of TShape.State changed (so only on fields ignored by EqualsNoTransform).

Public function InternalOctreeTriangles: TTriangleOctree;

The dynamic octree containing all triangles. It contains only triangles within this shape.

There is no distinction here between collidable / visible (as for TCastleSceneCore octrees), since only the whole shape may be marked as visible and/or collidable, not particular triangles.

The triangles are specified in local coordinate system of this shape (that is, they are independent from transformation within State.Transform). This allows the tree to remain unmodified when transformation of this shape changes.

This is automatically managed (initialized, updated, and used) by parent TCastleSceneCore. You usually don't need to know about this octree from outside.

To initialize this, add ssTriangles to InternalSpatial property, otherwise it's Nil. Parent TCastleSceneCore will take care of this (when parent TCastleSceneCore.Spatial contains ssDynamicCollisions, then all shapes contain ssTriangles within their InternalSpatial).

Parent TCastleSceneCore will take care to keep this octree always updated.

Parent TCastleSceneCore will also take care of actually using this octree: TCastleSceneCore.OctreeCollisions methods actually use the octrees of specific shapes at the bottom.

Public function InternalTriangleOctreeLimits: POctreeLimits;

Properties of created triangle octrees. See TriangleOctree unit comments for description.

Default value comes from DefLocalTriangleOctreeLimits.

They are used only when the octree is created, so usually you want to set them right before changing InternalSpatial from [] to something else.

Public function AlphaChannel: TAlphaChannel;

How should the alpha of the resulting calculation be used. Should we use alpha blending (partial transparency), or alpha test (yes-or-no transparency) or none of it (shape is simply opaque).

This is determined looking at the TAppearanceNode.AlphaChannel field. By default, it is acAuto, which in turn means that the final value of this method (which cannot be acAuto) is calculated looking at material, color, texture nodes data (including at texture images contents).

Public function Blending: boolean; deprecated 'use "AlphaChannel = acBlending"';

Warning: this symbol is deprecated: use "AlphaChannel = acBlending"

 
Public function Transparent: boolean; deprecated 'use "AlphaChannel = acBlending"';

Warning: this symbol is deprecated: use "AlphaChannel = acBlending"

 
Public function Visible: boolean;

Is the shape visible. Most shapes are visible, except when placed in TCollisionNode.Proxy (which allows to define invisible shapes, only for collision purposes).

Public function Collidable: boolean;

Is the shape collidable. Most shapes are collidable. One exception is when TAbstractShapeNode.Collision is set to scNone, which disables collisions. Another exception is when the shape is placed inside TCollisionNode children, and then you use TCollisionNode.Enabled to turn off collisions, or TCollisionNode.Proxy to provide alternative geometry for collisions.

Public function RayCollision( const Tag: TMailboxTag; out Intersection: TVector3; out IntersectionDistance: Single; const RayOrigin, RayDirection: TVector3; const ReturnClosestIntersection: boolean; const TriangleToIgnore: PTriangle; const IgnoreMarginAtStart: boolean; const TrianglesToIgnoreFunc: TTriangleIgnoreFunc): PTriangle;

Equivalent to using OctreeTriangles.RayCollision, except this wil use the mailbox.

Public function SegmentCollision( const Tag: TMailboxTag; out Intersection: TVector3; out IntersectionDistance: Single; const Pos1, Pos2: TVector3; const ReturnClosestIntersection: boolean; const TriangleToIgnore: PTriangle; const IgnoreMarginAtStart: boolean; const TrianglesToIgnoreFunc: TTriangleIgnoreFunc): PTriangle;

Equivalent to using OctreeTriangles.SegmentCollision, except this wil use the mailbox.

Public function NormalsSmooth(const FromCcw: boolean): TVector3List;

Create normals suitable for this shape.

You can call this only when Geometry is coordinate-based X3D geometry, implementing Coord and having non-empty coordinates (that is, Geometry.Coord returns True and sets ACoord <> Nil), and having Geometry.CoordIndex <> Nil.

For NormalsSmooth, also Geometry.CoordIndex = Nil is allowed, but make sure that Geometry.InternalCoordPolygons is available. See CreateSmoothNormalsCoordinateNode.

  • Smooth normals are perfectly smooth, per-vertex.

    As an exception, you can call this even when coords are currently empty (Geometry.Coord returns True but ACoord is Nil), then result is also Nil.

  • Flat normals are per-face. Calculated by CreateFlatNormals.

  • Finally NormalsCreaseAngle creates separate normal per index (auto-smoothing by CreaseAngle).

The normals here are cached. So using these methods makes condiderable speedup if the shape will not change (Changed method) and will need normals many times (e.g. will be rendered many times).

Public function NormalsFlat(const FromCcw: boolean): TVector3List;
 
Public function NormalsCreaseAngle(const FromCcw: boolean; const CreaseAngle: Single): TVector3List;
 
Public function EnumerateTextures(const Enumerate: TEnumerateShapeTexturesFunction): Pointer; override;
 
Public function UsesTexture(Node: TAbstractTextureNode): boolean;

Is the texture node Node possibly used by this shape. This is equivalent to checking does EnumerateShapeTextures return this shape.

Public function ShadowCaster: boolean;

Check is shape a shadow caster. Looks at Shape's Appearance.shadowCaster field (see https://castle-engine.io/x3d_extensions.php#section_ext_shadow_caster).

Public procedure Triangulate(const TriangleEvent: TTriangleEvent);

Triangulate shape. Calls TriangleEvent callback for each triangle. LocalTriangulate returns coordinates in local shape transformation (that is, not transformed by State.Transform yet).

Public procedure LocalTriangulate(const TriangleEvent: TTriangleEvent);
 
Public function DebugInfo(const Indent: string = ''): string; override;
 
Public function NiceName: string;
 
Public function Node: TAbstractShapeNode;

Shape node in X3D graph. This is always non-nil for X3D, VRML 2 and all model formats that are imported as X3D, like glTF, Spine, sprite sheets and more. This is Nil only for old VRML 1.0 and Inventor model formats.

Public function GeometryParentNodeName: String; deprecated 'use GeometryParentNode.X3DName';

Warning: this symbol is deprecated: use GeometryParentNode.X3DName

 
Public function GeometryGrandParentNodeName: String; deprecated 'use GeometryGrandParentNode.X3DName';

Warning: this symbol is deprecated: use GeometryGrandParentNode.X3DName

 
Public function GeometryGrandGrandParentNodeName: String; deprecated 'use GeometryGrandGrandParentNode.X3DName';

Warning: this symbol is deprecated: use GeometryGrandGrandParentNode.X3DName

 
Public function InternalMaterialProperty: TMaterialProperty;

Material property associated with this shape's material/texture.

Public function MaterialProperty: TMaterialProperty; deprecated 'use InternalMaterialProperty, or (better) do not use it at all -- this is internal';

Warning: this symbol is deprecated: use InternalMaterialProperty, or (better) do not use it at all -- this is internal

 

Properties

Public property OriginalGeometry: TAbstractGeometryNode read FOriginalGeometry;

Original geometry node, that you get from a VRML/X3D graph.

Public property OriginalState: TX3DGraphTraverseState read FOriginalState;

Original state, that you get from a VRML/X3D graph.

Public property InternalSpatial: TShapeSpatialStructures read FSpatial write SetSpatial;

Which spatial structrues (octrees, for now) should be created and managed. This works analogous to TCastleSceneCore.Spatial, but this manages octrees within this TShape.

Parent TCastleSceneCore will take care to keep this value updated, you should only set TCastleSceneCore.Spatial from the outside.

Public property InternalTriangleOctreeProgressTitle: string read FTriangleOctreeProgressTitle write FTriangleOctreeProgressTitle;

If TriangleOctreeProgressTitle <> '', it will be shown during octree creation (through TProgress.Title). Will be shown only if progress is not active already (so we avoid starting "progress bar within progress bar").

Public property DynamicGeometry: Boolean read FDynamicGeometry;

Local geometry changes very often (like every frame). This is automatically detected and set to True. May be used as an optimization hint.

Public property GeometryParentNode: TX3DNode read FGeometryParentNode;

Parent, grand-parent, grand-grand-parent nodes determined during traversing of the X3D node graph.

Note that GeometryParentNode is almost always equal to Node, for X3D, VRML 2 and all model formats that are imported as X3D, like glTF, Spine, sprite sheets and more. That's because in VRML 2 and X3D, parent of geometry node must be a TShapeNode.

Only in old VRML 1.0 and Inventor model formats the GeometryParentNode may be different than Node.

All these nodes (GeometryParentNode, GeometryGrandParentNode and GeometryGrandGrandParentNode) may be useful if you need to take a different action depending on the parent nodes of this shape.

Public property GeometryGrandParentNode: TX3DNode read FGeometryGrandParentNode;
 
Public property GeometryGrandGrandParentNode: TX3DNode read FGeometryGrandGrandParentNode;
 

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