import {PerformanceModel} from '@xeokit/xeokit-sdk/src/viewer/scene/PerformanceModel/PerformanceModel.js'
PerformanceModel
Extends:
Implements:
- Drawable ,
- Entity
A high-performance model representation for efficient rendering and low memory usage.
Examples
- PerformanceModel using geometry batching
- PerformanceModel using geometry batching and RTC coordinates
- PerformanceModel using geometry instancing
- PerformanceModel using geometry instancing and RTC coordinates
Overview
While xeokit's standard scene graph is great for gizmos and medium-sized models, it doesn't scale up to millions of objects in terms of memory and rendering efficiency.
For huge models, we have the PerformanceModel
representation, which is optimized to pack large amounts of geometry into memory and render it efficiently using WebGL.
PerformanceModel
is the default model representation loaded by (at least) GLTFLoaderPlugin, XKTLoaderPlugin and WebIFCLoaderPlugin.
In this tutorial you'll learn how to use PerformanceModel
to create high-detail content programmatically. Ordinarily you'd be learning about PerformanceModel
if you were writing your own model loader plugins.
Contents
- PerformanceModel
- GPU-Resident Geometry
- Picking
- Example 1: Geometry Instancing
- Finalizing a PerformanceModel
- Finding Entities
- Example 2: Geometry Batching
- Classifying with Metadata
- Querying Metadata
- Metadata Structure
- RTC Coordinates
PerformanceModel
PerformanceModel
uses two rendering techniques internally:
- Geometry batching for unique geometries, combining those into a single WebGL geometry buffer, to render in one draw call, and
- geometry instancing for geometries that are shared by multiple meshes, rendering all instances of each shared geometry in one draw call.
These techniques come with certain limitations:
- Non-realistic rendering - while scene graphs can use xeokit's full set of material workflows,
PerformanceModel
uses simple Lambertian shading without textures. - Static transforms - transforms within a
PerformanceModel
are static and cannot be dynamically translated, rotated and scaled the way Nodes and Meshes in scene graphs can. - Immutable model representation - while scene graph Nodes and
Meshes can be dynamically plugged together,
PerformanceModel
is immutable, since it packs its geometries into buffers and instanced arrays.
PerformanceModel
's API allows us to exploit batching and instancing, while exposing its elements as
abstract Entity types.
Entity is the abstract base class for the various xeokit components that represent models, objects, or anonymous visible elements. An Entity has a unique ID and can be individually shown, hidden, selected, highlighted, ghosted, culled, picked and clipped, and has its own World-space boundary.
- A
PerformanceModel
is an Entity that represents a model. - A
PerformanceModel
represents each of its objects with an Entity. - Each Entity has one or more meshes that define its shape.
- Each mesh has either its own unique geometry, or shares a geometry with other meshes.
GPU-Resident Geometry
For a low memory footprint, PerformanceModel
stores its geometries in GPU memory only, compressed (quantized) as integers. Unfortunately, GPU-resident geometry is
not readable by JavaScript.
Example 1: Geometry Instancing
In the example below, we'll use a PerformanceModel
to build a simple table model using geometry instancing.
We'll start by adding a reusable box-shaped geometry to our PerformanceModel
.
Then, for each object in our model we'll add an Entity that has a mesh that instances our box geometry, transforming and coloring the instance.
import {Viewer, PerformanceModel} from "xeokit-sdk.es.js";
const viewer = new Viewer({
canvasId: "myCanvas",
transparent: true
});
viewer.scene.camera.eye = [-21.80, 4.01, 6.56];
viewer.scene.camera.look = [0, -5.75, 0];
viewer.scene.camera.up = [0.37, 0.91, -0.11];
// Build a PerformanceModel representing a table
// with four legs, using geometry instancing
const performanceModel = new PerformanceModel(viewer.scene, {
id: "table",
isModel: true, // <--- Registers PerformanceModel in viewer.scene.models
position: [0, 0, 0],
scale: [1, 1, 1],
rotation: [0, 0, 0]
});
// Create a reusable geometry within the PerformanceModel
// We'll instance this geometry by five meshes
performanceModel.createGeometry({
id: "myBoxGeometry",
// The primitive type - allowed values are "points", "lines" and "triangles".
// See the OpenGL/WebGL specification docs
// for how the coordinate arrays are supposed to be laid out.
primitive: "triangles",
// The vertices - eight for our cube, each
// one spanning three array elements for X,Y and Z
positions: [
1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1, // v0-v1-v2-v3 front
1, 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, // v0-v3-v4-v1 right
1, 1, 1, 1, 1, -1, -1, 1, -1, -1, 1, 1, // v0-v1-v6-v1 top
-1, 1, 1, -1, 1, -1, -1, -1, -1, -1, -1, 1, // v1-v6-v7-v2 left
-1, -1, -1, 1, -1, -1, 1, -1, 1, -1, -1, 1, // v7-v4-v3-v2 bottom
1, -1, -1, -1, -1, -1, -1, 1, -1, 1, 1, -1 // v4-v7-v6-v1 back
],
// Normal vectors, one for each vertex
normals: [
0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, // v0-v1-v2-v3 front
1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v0-v3-v4-v5 right
0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, // v0-v5-v6-v1 top
-1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, // v1-v6-v7-v2 left
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, // v7-v4-v3-v2 bottom
0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1 // v4-v7-v6-v5 back
],
// Indices - these organise the positions and and normals
// into geometric primitives in accordance with the "primitive" parameter,
// in this case a set of three indices for each triangle.
//
// Note that each triangle is specified in counter-clockwise winding order.
//
indices: [
0, 1, 2, 0, 2, 3, // front
4, 5, 6, 4, 6, 7, // right
8, 9, 10, 8, 10, 11, // top
12, 13, 14, 12, 14, 15, // left
16, 17, 18, 16, 18, 19, // bottom
20, 21, 22, 20, 22, 23
]
});
// Red table leg
performanceModel.createMesh({
id: "redLegMesh",
geometryId: "myBoxGeometry",
position: [-4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1, 0.3, 0.3]
});
performanceModel.createEntity({
id: "redLeg",
meshIds: ["redLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Green table leg
performanceModel.createMesh({
id: "greenLegMesh",
geometryId: "myBoxGeometry",
position: [4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 1.0, 0.3]
});
performanceModel.createEntity({
id: "greenLeg",
meshIds: ["greenLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Blue table leg
performanceModel.createMesh({
id: "blueLegMesh",
geometryId: "myBoxGeometry",
position: [4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 0.3, 1.0]
});
performanceModel.createEntity({
id: "blueLeg",
meshIds: ["blueLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Yellow table leg
performanceModel.createMesh({
id: "yellowLegMesh",
geometryId: "myBoxGeometry",
position: [-4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1.0, 1.0, 0.0]
});
performanceModel.createEntity({
id: "yellowLeg",
meshIds: ["yellowLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Purple table top
performanceModel.createMesh({
id: "purpleTableTopMesh",
geometryId: "myBoxGeometry",
position: [0, -3, 0],
scale: [6, 0.5, 6],
rotation: [0, 0, 0],
color: [1.0, 0.3, 1.0]
});
performanceModel.createEntity({
id: "purpleTableTop",
meshIds: ["purpleTableTopMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
Finalizing a PerformanceModel
Before we can view and interact with our PerformanceModel
, we need to finalize it. Internally, this causes the PerformanceModel
to build the
vertex buffer objects (VBOs) that support our geometry instances. When using geometry batching (see next example),
this causes PerformanceModel
to build the VBOs that combine the batched geometries. Note that you can do both instancing and
batching within the same PerformanceModel
.
Once finalized, we can't add anything more to our PerformanceModel
.
performanceModel.finalize();
Finding Entities
As mentioned earlier, Entity is the abstract base class for components that represent models, objects, or just anonymous visible elements.
Since we created configured our PerformanceModel
with isModel: true
,
we're able to find it as an Entity by ID in viewer.scene.models
. Likewise, since
we configured each of its Entities with isObject: true
, we're able to
find them in viewer.scene.objects
.
// Get the whole table model Entity
const table = viewer.scene.models["table"];
// Get some leg object Entities
const redLeg = viewer.scene.objects["redLeg"];
const greenLeg = viewer.scene.objects["greenLeg"];
const blueLeg = viewer.scene.objects["blueLeg"];
Example 2: Geometry Batching
Let's once more use a PerformanceModel
to build the simple table model, this time exploiting geometry batching.
import {Viewer, PerformanceModel} from "xeokit-sdk.es.js";
const viewer = new Viewer({
canvasId: "myCanvas",
transparent: true
});
viewer.scene.camera.eye = [-21.80, 4.01, 6.56];
viewer.scene.camera.look = [0, -5.75, 0];
viewer.scene.camera.up = [0.37, 0.91, -0.11];
// Create a PerformanceModel representing a table with four legs, using geometry batching
const performanceModel = new PerformanceModel(viewer.scene, {
id: "table",
isModel: true, // <--- Registers PerformanceModel in viewer.scene.models
position: [0, 0, 0],
scale: [1, 1, 1],
rotation: [0, 0, 0]
});
// Red table leg
performanceModel.createMesh({
id: "redLegMesh",
// Geometry arrays are same as for the earlier batching example
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [-4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1, 0.3, 0.3]
});
performanceModel.createEntity({
id: "redLeg",
meshIds: ["redLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Green table leg
performanceModel.createMesh({
id: "greenLegMesh",
primitive: "triangles",
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 1.0, 0.3]
});
performanceModel.createEntity({
id: "greenLeg",
meshIds: ["greenLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Blue table leg
performanceModel.createMesh({
id: "blueLegMesh",
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 0.3, 1.0]
});
performanceModel.createEntity({
id: "blueLeg",
meshIds: ["blueLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Yellow table leg object
performanceModel.createMesh({
id: "yellowLegMesh",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [-4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1.0, 1.0, 0.0]
});
performanceModel.createEntity({
id: "yellowLeg",
meshIds: ["yellowLegMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Purple table top
performanceModel.createMesh({
id: "purpleTableTopMesh",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [0, -3, 0],
scale: [6, 0.5, 6],
rotation: [0, 0, 0],
color: [1.0, 0.3, 1.0]
});
performanceModel.createEntity({
id: "purpleTableTop",
meshIds: ["purpleTableTopMesh"],
isObject: true // <---- Registers Entity by ID on viewer.scene.objects
});
// Finalize the PerformanceModel.
performanceModel.finalize();
// Find BigModelNodes by their model and object IDs
// Get the whole table model
const table = viewer.scene.models["table"];
// Get some leg objects
const redLeg = viewer.scene.objects["redLeg"];
const greenLeg = viewer.scene.objects["greenLeg"];
const blueLeg = viewer.scene.objects["blueLeg"];
Classifying with Metadata
In the previous examples, we used PerformanceModel
to build
two versions of the same table model, to demonstrate geometry batching and geometry instancing.
We'll now classify our Entitys with metadata. This metadata will work the same for both our examples, since they create the exact same structure of Entitys to represent their models and objects. The abstract Entity type is, after all, intended to provide an abstract interface through which differently-implemented scene content can be accessed uniformly.
To create the metadata, we'll create a MetaModel for our model, with a MetaObject for each of it's objects. The MetaModel and MetaObjects get the same IDs as the Entitys that represent their model and objects within our scene.
const furnitureMetaModel = viewer.metaScene.createMetaModel("furniture", { // Creates a MetaModel in the MetaScene
"projectId": "myTableProject",
"revisionId": "V1.0",
"metaObjects": [
{ // Creates a MetaObject in the MetaModel
"id": "table",
"name": "Table", // Same ID as an object Entity
"type": "furniture", // Arbitrary type, could be IFC type
"properties": { // Arbitrary properties, could be IfcPropertySet
"cost": "200"
}
},
{
"id": "redLeg",
"name": "Red table Leg",
"type": "leg",
"parent": "table", // References first MetaObject as parent
"properties": {
"material": "wood"
}
},
{
"id": "greenLeg", // Node with corresponding id does not need to exist
"name": "Green table leg", // and MetaObject does not need to exist for Node with an id
"type": "leg",
"parent": "table",
"properties": {
"material": "wood"
}
},
{
"id": "blueLeg",
"name": "Blue table leg",
"type": "leg",
"parent": "table",
"properties": {
"material": "wood"
}
},
{
"id": "yellowLeg",
"name": "Yellow table leg",
"type": "leg",
"parent": "table",
"properties": {
"material": "wood"
}
},
{
"id": "tableTop",
"name": "Purple table top",
"type": "surface",
"parent": "table",
"properties": {
"material": "formica",
"width": "60",
"depth": "60",
"thickness": "5"
}
}
]
});
Querying Metadata
Having created and classified our model (either the instancing or batching example), we can now find the MetaModel and MetaObjects using the IDs of their corresponding Entitys.
const furnitureMetaModel = scene.metaScene.metaModels["furniture"];
const redLegMetaObject = scene.metaScene.metaObjects["redLeg"];
In the snippet below, we'll log metadata on each Entity we click on:
viewer.scene.input.on("mouseclicked", function (coords) {
const hit = viewer.scene.pick({
canvasPos: coords
});
if (hit) {
const entity = hit.entity;
const metaObject = viewer.metaScene.metaObjects[entity.id];
if (metaObject) {
console.log(JSON.stringify(metaObject.getJSON(), null, "\t"));
}
}
});
Metadata Structure
The MetaModel organizes its MetaObjects in a tree that describes their structural composition:
// Get metadata on the root object
const tableMetaObject = furnitureMetaModel.rootMetaObject;
// Get metadata on the leg objects
const redLegMetaObject = tableMetaObject.children[0];
const greenLegMetaObject = tableMetaObject.children[1];
const blueLegMetaObject = tableMetaObject.children[2];
const yellowLegMetaObject = tableMetaObject.children[3];
Given an Entity, we can find the object or model of which it is a part, or the objects that comprise it. We can also generate UI components from the metadata, such as the tree view demonstrated in this demo.
This hierarchy allows us to express the hierarchical structure of a model while representing it in
various ways in the 3D scene (such as with PerformanceModel
, which
has a non-hierarchical scene representation).
Note also that a MetaObject does not need to have a corresponding Entity and vice-versa.
RTC Coordinates for Double Precision
PerformanceModel
can emulate 64-bit precision on GPUs using relative-to-center (RTC) coordinates.
Consider a model that contains many small objects, but with such large spatial extents that 32 bits of GPU precision (accurate to ~7 digits) will not be sufficient to render all of the the objects without jittering.
To prevent jittering, we could spatially subdivide the objects into "tiles". Each tile would have a center position, and the positions of the objects within the tile would be relative to that center ("RTC coordinates").
While the center positions of the tiles would be 64-bit values, the object positions only need to be 32-bit.
Internally, when rendering an object with RTC coordinates, xeokit first temporarily translates the camera viewing matrix by the object's tile's RTC center, on the CPU, using 64-bit math.
Then xeokit loads the viewing matrix into its WebGL shaders, where math happens at 32-bit precision. Within the shaders, the matrix is effectively down-cast to 32-bit precision, and the object's 32-bit vertex positions are transformed by the matrix.
We see no jittering, because with RTC a detectable loss of GPU accuracy only starts happening to objects as they become very distant from the camera viewpoint, at which point they are too small to be discernible anyway.
RTC Coordinates with Geometry Instancing
To use RTC with PerformanceModel
geometry instancing, we specify an RTC center for the geometry via its origin
parameter. Then PerformanceModel
assumes that all meshes that instance that geometry are within the same RTC coordinate system, ie. the meshes position
and rotation
properties are assumed to be relative to the geometry's origin
.
For simplicity, our example's meshes all instance the same geometry. Therefore, our example model has only one RTC center.
Note that the axis-aligned World-space boundary (AABB) of our model is [ -6, -9, -6, 1000000006, -2.5, 1000000006]
.
const origin = [100000000, 0, 100000000];
performanceModel.createGeometry({
id: "box",
origin: origin, // This geometry's positions, and the transforms of all meshes that instance the geometry, are relative to the RTC center
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
});
performanceModel.createMesh({
id: "leg1",
geometryId: "box",
position: [-4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1, 0.3, 0.3]
});
performanceModel.createEntity({
meshIds: ["leg1"],
isObject: true
});
performanceModel.createMesh({
id: "leg2",
geometryId: "box",
position: [4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 1.0, 0.3]
});
performanceModel.createEntity({
meshIds: ["leg2"],
isObject: true
});
performanceModel.createMesh({
id: "leg3",
geometryId: "box",
position: [4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 0.3, 1.0]
});
performanceModel.createEntity({
meshIds: ["leg3"],
isObject: true
});
performanceModel.createMesh({
id: "leg4",
geometryId: "box",
position: [-4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1.0, 1.0, 0.0]
});
performanceModel.createEntity({
meshIds: ["leg4"],
isObject: true
});
performanceModel.createMesh({
id: "top",
geometryId: "box",
position: [0, -3, 0],
scale: [6, 0.5, 6],
rotation: [0, 0, 0],
color: [1.0, 0.3, 1.0]
});
performanceModel.createEntity({
meshIds: ["top"],
isObject: true
});
RTC Coordinates with Geometry Batching
To use RTC with PerformanceModel
geometry batching, we specify an RTC center (origin
) for each mesh. For performance, we try to have as many meshes share the same value for origin
as possible. Each mesh's positions
, position
and rotation
properties are assumed to be relative to origin
.
For simplicity, the meshes in our example all share the same RTC center.
The axis-aligned World-space boundary (AABB) of our model is [ -6, -9, -6, 1000000006, -2.5, 1000000006]
.
const origin = [100000000, 0, 100000000];
performanceModel.createMesh({
id: "leg1",
origin: origin, // This mesh's positions and transforms are relative to the RTC center
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [-4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1, 0.3, 0.3]
});
performanceModel.createEntity({
meshIds: ["leg1"],
isObject: true
});
performanceModel.createMesh({
id: "leg2",
origin: origin, // This mesh's positions and transforms are relative to the RTC center
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 1.0, 0.3]
});
performanceModel.createEntity({
meshIds: ["leg2"],
isObject: true
});
performanceModel.createMesh({
id: "leg3",
origin: origin, // This mesh's positions and transforms are relative to the RTC center
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 0.3, 1.0]
});
performanceModel.createEntity({
meshIds: ["leg3"],
isObject: true
});
performanceModel.createMesh({
id: "leg4",
origin: origin, // This mesh's positions and transforms are relative to the RTC center
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [-4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1.0, 1.0, 0.0]
});
performanceModel.createEntity({
meshIds: ["leg4"],
isObject: true
});
performanceModel.createMesh({
id: "top",
origin: origin, // This mesh's positions and transforms are relative to the RTC center
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
position: [0, -3, 0],
scale: [6, 0.5, 6],
rotation: [0, 0, 0],
color: [1.0, 0.3, 1.0]
});
performanceModel.createEntity({
meshIds: ["top"],
isObject: true
});
Positioning at World-space coordinates
To position a PerformanceModel at given double-precision World coordinates, we can
configure the origin
of the PerformanceModel itself. The origin
is a double-precision
3D World-space position at which the PerformanceModel will be located.
Note that position
is a single-precision offset relative to origin
.
const origin = [100000000, 0, 100000000];
const performanceModel = new PerformanceModel(viewer.scene, {
id: "table",
isModel: true,
origin: origin, // Everything in this PerformanceModel is relative to this RTC center
position: [0, 0, 0],
scale: [1, 1, 1],
rotation: [0, 0, 0]
});
performanceModel.createGeometry({
id: "box",
primitive: "triangles",
positions: [ 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, -1, 1 ... ],
normals: [ 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, ... ],
indices: [ 0, 1, 2, 0, 2, 3, 4, 5, 6, 4, 6, 7, ... ],
});
performanceModel.createMesh({
id: "leg1",
geometryId: "box",
position: [-4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1, 0.3, 0.3]
});
performanceModel.createEntity({
meshIds: ["leg1"],
isObject: true
});
performanceModel.createMesh({
id: "leg2",
geometryId: "box",
position: [4, -6, -4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 1.0, 0.3]
});
performanceModel.createEntity({
meshIds: ["leg2"],
isObject: true
});
performanceModel.createMesh({
id: "leg3",
geometryId: "box",
position: [4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [0.3, 0.3, 1.0]
});
performanceModel.createEntity({
meshIds: ["leg3"],
isObject: true
});
performanceModel.createMesh({
id: "leg4",
geometryId: "box",
position: [-4, -6, 4],
scale: [1, 3, 1],
rotation: [0, 0, 0],
color: [1.0, 1.0, 0.0]
});
performanceModel.createEntity({
meshIds: ["leg4"],
isObject: true
});
performanceModel.createMesh({
id: "top",
geometryId: "box",
position: [0, -3, 0],
scale: [6, 0.5, 6],
rotation: [0, 0, 0],
color: [1.0, 0.3, 1.0]
});
performanceModel.createEntity({
meshIds: ["top"],
isObject: true
});
Constructor Summary
Public Constructor | ||
public |
constructor(owner: Component, cfg: *) |
Member Summary
Public Members | ||
public get |
Gets the PerformanceModel's World-space 3D axis-aligned bounding box. Represented by a six-element Float64Array containing the min/max extents of the
axis-aligned volume, ie. |
|
public get |
Sets if backfaces are rendered for this PerformanceModel. |
|
public set |
Sets if backfaces are rendered for this PerformanceModel. |
|
public get |
Gets if this PerformanceModel casts a shadow. |
|
public set |
Sets if this PerformanceModel casts a shadow. |
|
public get |
Gets if Entitys in this PerformanceModel are clippable. |
|
public set |
Sets if Entitys in this PerformanceModel are clippable. |
|
public get |
Gets if this PerformanceModel is collidable. |
|
public set |
Sets if Entitys in this PerformanceModel are collidable. |
|
public get |
Gets the RGB colorize color for this PerformanceModel. |
|
public set |
Sets the RGB colorize color for this PerformanceModel. |
|
public get |
Gets if this PerformanceModel is culled from view. |
|
public set |
Sets if this PerformanceModel is culled from view. |
|
public get |
Configures the appearance of edges of Entitys within this PerformanceModel. |
|
public get |
Gets if any Entitys in this PerformanceModel have edges emphasised. |
|
public set |
Sets if all Entitys in this PerformanceModel have edges emphasised. |
|
public get |
entityList: Entity[]: * Gets the list of Entitys within this PerformanceModel. |
|
public get |
Configures the appearance of highlighted Entitys within this PerformanceModel. |
|
public get |
Gets if any Entitys in this PerformanceModel are highlighted. |
|
public set |
Sets if all Entitys in this PerformanceModel are highlighted. |
|
public get |
Returns true to indicate that PerformanceModel is implements Drawable. |
|
public get |
Returns true to indicate that PerformanceModel is an Entity. |
|
public get |
Returns |
|
public get |
Returns |
|
public get |
Returns true to indicate that this Component is a PerformanceModel. |
|
public get |
Gets the PerformanceModel's local modeling transform matrix. Default value is |
|
public get |
The approximate number of line primitives in this PerformanceModel. |
|
public get |
The approximate number of point primitives in this PerformanceModel. |
|
public get |
The approximate number of triangle primitives in this PerformanceModel. |
|
public get |
objects: * | {}: * Returns the Entitys in this PerformanceModel. |
|
public get |
Gets this PerformanceModel's opacity factor. This is a factor in range |
|
public set |
Sets the opacity factor for this PerformanceModel. |
|
public get abstract |
Gets the 3D World-space origin for this PerformanceModel. |
|
public get |
Gets if physically-based rendering (PBR) is enabled for this PerformanceModel. |
|
public get |
Gets if this PerformanceModel is pickable. |
|
public set |
Sets if Entitys in this PerformanceModel are pickable. |
|
public get |
Gets the PerformanceModel's local translation. Default value is |
|
public get |
quaternion: Number[] Gets the PerformanceModels's local rotation quaternion. Default value is |
|
public get |
Sets if this PerformanceModel can have shadow cast upon it. |
|
public set |
Sets if this PerformanceModel can have shadow cast upon it. |
|
public get |
Gets the PerformanceModel's local rotation, as Euler angles given in degrees, for each of the X, Y and Z axis. Default value is |
|
public get |
Gets if Scalable Ambient Obscurance (SAO) will apply to this PerformanceModel. |
|
public get |
Gets the PerformanceModel's local scale. Default value is |
|
public get |
Gets if any Entitys in this PerformanceModel are selected. |
|
public set |
Sets if all Entitys in this PerformanceModel are selected. |
|
public get |
Configures the appearance of selected Entitys within this PerformanceModel. |
|
public get |
Gets if any Entitys in this PerformanceModel are visible. |
|
public set |
Sets if this PerformanceModel is visible. |
|
public get |
Gets the PerformanceModel's World matrix. |
|
public get |
Gets the PerformanceModel's World normal matrix. |
|
public get |
Configures the appearance of xrayed Entitys within this PerformanceModel. |
|
public get |
Gets if any Entitys in this PerformanceModel are xrayed. |
|
public set |
Sets if all Entitys in this PerformanceModel are xrayed. |
Method Summary
Public Methods | ||
public |
createEntity(cfg: Object): Entity Creates an Entity within this PerformanceModel, giving it one or more meshes previously created with PerformanceModel#createMesh. |
|
public |
createGeometry(cfg: *) Creates a reusable geometry within this PerformanceModel. |
|
public |
createMesh(cfg: object): * Creates a mesh within this PerformanceModel. |
|
public |
destroy() Destroys this PerformanceModel. |
|
public |
finalize() Finalizes this PerformanceModel. |
Inherited Summary
From class Component | ||
public get |
The Component that owns the lifecycle of this Component, if any. |
|
public |
True as soon as this Component has been destroyed |
|
public |
ID of this Component, unique within the Scene. |
|
public |
meta: * Arbitrary, user-defined metadata on this component. |
|
public |
The parent Scene that contains this Component. |
|
public |
The viewer that contains this Scene. |
|
public |
clear() Destroys all Components that are owned by this. |
|
public |
destroy() Destroys this component. |
|
public |
Logs an error for this component to the JavaScript console. |
|
public |
Fires an event on this component. |
|
public |
Returns true if there are any subscribers to the given event on this component. |
|
public |
Tests if this component is of the given type, or is a subclass of the given type. |
|
public |
Logs a console debugging message for this component. |
|
public |
Cancels an event subscription that was previously made with Component#on or Component#once. |
|
public |
Subscribes to an event on this component. |
|
public |
Subscribes to the next occurrence of the given event, then un-subscribes as soon as the event is subIdd. |
|
public |
Logs a warning for this component to the JavaScript console. |
Public Constructors
public constructor(owner: Component, cfg: *) source
Override:
Component#constructorParams:
Name | Type | Attribute | Description |
owner | Component | Owner component. When destroyed, the owner will destroy this component as well. |
|
cfg | * |
|
Configs |
cfg.id | String |
|
Optional ID, unique among all components in the parent scene, generated automatically when omitted. |
cfg.isModel | Boolean |
|
Specify |
cfg.origin | Number[] |
|
World-space double-precision 3D origin. |
cfg.position | Number[] |
|
Local, single-precision 3D position, relative to the origin parameter. |
cfg.scale | Number[] |
|
Local scale. |
cfg.rotation | Number[] |
|
Local rotation, as Euler angles given in degrees, for each of the X, Y and Z axis. |
cfg.matrix | Number[] |
|
|
cfg.visible | Boolean |
|
Indicates if the PerformanceModel is initially visible. |
cfg.culled | Boolean |
|
Indicates if the PerformanceModel is initially culled from view. |
cfg.pickable | Boolean |
|
Indicates if the PerformanceModel is initially pickable. |
cfg.clippable | Boolean |
|
Indicates if the PerformanceModel is initially clippable. |
cfg.collidable | Boolean |
|
Indicates if the PerformanceModel is initially included in boundary calculations. |
cfg.xrayed | Boolean |
|
Indicates if the PerformanceModel is initially xrayed. |
cfg.highlighted | Boolean |
|
Indicates if the PerformanceModel is initially highlighted. |
cfg.selected | Boolean |
|
Indicates if the PerformanceModel is initially selected. |
cfg.edges | Boolean |
|
Indicates if the PerformanceModel's edges are initially emphasized. |
cfg.colorize | Number[] |
|
PerformanceModel's initial RGB colorize color, multiplies by the rendered fragment colors. |
cfg.opacity | Number |
|
PerformanceModel's initial opacity factor, multiplies by the rendered fragment alpha. |
cfg.backfaces | Number |
|
When we set this |
cfg.saoEnabled | Boolean |
|
Indicates if Scalable Ambient Obscurance (SAO) will apply to this PerformanceModel. SAO is configured by the Scene's SAO component. |
cfg.pbrEnabled | Boolean |
|
Indicates if physically-based rendering (PBR) will apply to the PerformanceModel. Only works when Scene#pbrEnabled is also |
cfg.edgeThreshold | Number |
|
When xraying, highlighting, selecting or edging, this is the threshold angle between normals of adjacent triangles, below which their shared wireframe edge is not drawn. |
cfg.maxGeometryBatchSize | Number |
|
Maximum geometry batch size, as number of vertices. This is optionally supplied
to limit the size of the batched geometry arrays that PerformanceModel internally creates for batched geometries.
A lower value means less heap allocation/de-allocation while creating/loading batched geometries, but more draw calls and
slower rendering speed. A high value means larger heap allocation/de-allocation while creating/loading, but less draw calls
and faster rendering speed. It's recommended to keep this somewhere roughly between |
Public Members
public get aabb: Number[] source
Gets the PerformanceModel's World-space 3D axis-aligned bounding box.
Represented by a six-element Float64Array containing the min/max extents of the
axis-aligned volume, ie. [xmin, ymin,zmin,xmax,ymax, zmax]
.
public get backfaces: Boolean source
Sets if backfaces are rendered for this PerformanceModel.
Default is false
.
public set backfaces: Boolean source
Sets if backfaces are rendered for this PerformanceModel.
Default is false
.
When we set this true
, then backfaces are always rendered for this PerformanceModel.
When we set this false
, then we allow the Viewer to decide whether to render backfaces. In this case,
the Viewer will:
- hide backfaces on watertight meshes,
- show backfaces on open meshes, and
- always show backfaces on meshes when we slice them open with SectionPlanes.
public get clippable: Boolean source
Gets if Entitys in this PerformanceModel are clippable.
Clipping is done by the SectionPlanes in Scene#sectionPlanes.
public set clippable: Boolean source
Sets if Entitys in this PerformanceModel are clippable.
Clipping is done by the SectionPlanes in Scene#sectionPlanes.
public get colorize: Number[] source
Gets the RGB colorize color for this PerformanceModel.
Each element of the color is in range [0..1]
.
public set colorize: Number[] source
Sets the RGB colorize color for this PerformanceModel.
Multiplies by rendered fragment colors.
Each element of the color is in range [0..1]
.
public get culled: Boolean source
Gets if this PerformanceModel is culled from view.
The PerformanceModel is only rendered when PerformanceModel#visible is true and PerformanceModel#culled is false.
public set culled: Boolean source
Sets if this PerformanceModel is culled from view.
The PerformanceModel is only rendered when PerformanceModel#visible is true and PerformanceModel#culled is false.
public get edgeMaterial: EdgeMaterial source
Configures the appearance of edges of Entitys within this PerformanceModel.
This is the Scene#edgeMaterial.
public get edges: Boolean source
Gets if any Entitys in this PerformanceModel have edges emphasised.
public set edges: Boolean source
Sets if all Entitys in this PerformanceModel have edges emphasised.
public get highlightMaterial: EmphasisMaterial source
Configures the appearance of highlighted Entitys within this PerformanceModel.
This is the Scene#highlightMaterial.
public get highlighted: Boolean source
Gets if any Entitys in this PerformanceModel are highlighted.
public set highlighted: Boolean source
Sets if all Entitys in this PerformanceModel are highlighted.
public get isDrawable: Boolean source
Returns true to indicate that PerformanceModel is implements Drawable.
public get isModel: Boolean source
Returns true
if this PerformanceModel represents a model.
When true
the PerformanceModel will be registered by PerformanceModel#id in
Scene#models and may also have a MetaObject with matching MetaObject#id.
public get isObject: Boolean source
Returns false
to indicate that PerformanceModel never represents an object.
public get isPerformanceModel: Boolean source
Returns true to indicate that this Component is a PerformanceModel.
public get matrix: Number[] source
Gets the PerformanceModel's local modeling transform matrix.
Default value is [1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1]
.
public get numLines: Number source
The approximate number of line primitives in this PerformanceModel.
public get numPoints: Number source
The approximate number of point primitives in this PerformanceModel.
public get numTriangles: Number source
The approximate number of triangle primitives in this PerformanceModel.
public get opacity: Number source
Gets this PerformanceModel's opacity factor.
This is a factor in range [0..1]
which multiplies by the rendered fragment alphas.
public set opacity: Number source
Sets the opacity factor for this PerformanceModel.
This is a factor in range [0..1]
which multiplies by the rendered fragment alphas.
public get abstract origin: Float64Array source
Gets the 3D World-space origin for this PerformanceModel.
Each geometry or mesh origin, if supplied, is relative to this origin.
Default value is [0,0,0]
.
public get pbrEnabled: Boolean source
Gets if physically-based rendering (PBR) is enabled for this PerformanceModel.
Only works when Scene#pbrEnabled is also true.
public get pickable: Boolean source
Gets if this PerformanceModel is pickable.
Picking is done via calls to Scene#pick.
public set pickable: Boolean source
Sets if Entitys in this PerformanceModel are pickable.
Picking is done via calls to Scene#pick.
public get position: Number[] source
Gets the PerformanceModel's local translation.
Default value is [0,0,0]
.
public get quaternion: Number[] source
Gets the PerformanceModels's local rotation quaternion.
Default value is [0,0,0,1]
.
public get receivesShadow: Boolean source
Sets if this PerformanceModel can have shadow cast upon it.
public set receivesShadow: Boolean source
Sets if this PerformanceModel can have shadow cast upon it.
public get rotation: Number[] source
Gets the PerformanceModel's local rotation, as Euler angles given in degrees, for each of the X, Y and Z axis.
Default value is [0,0,0]
.
public get saoEnabled: Boolean source
Gets if Scalable Ambient Obscurance (SAO) will apply to this PerformanceModel.
SAO is configured by the Scene's SAO component.
Only works when SAO#enabled is also true.
public get scale: Number[] source
Gets the PerformanceModel's local scale.
Default value is [1,1,1]
.
public get selectedMaterial: EmphasisMaterial source
Configures the appearance of selected Entitys within this PerformanceModel.
This is the Scene#selectedMaterial.
public get visible: Boolean source
Gets if any Entitys in this PerformanceModel are visible.
The PerformanceModel is only rendered when PerformanceModel#visible is true
and PerformanceModel#culled is false
.
public set visible: Boolean source
Sets if this PerformanceModel is visible.
The PerformanceModel is only rendered when PerformanceModel#visible is true
and PerformanceModel#culled is false
.
*
public get worldMatrix: Number[] source
Gets the PerformanceModel's World matrix.
Properties:
Name | Type | Attribute | Description |
worldMatrix | * |
public get xrayMaterial: EmphasisMaterial source
Configures the appearance of xrayed Entitys within this PerformanceModel.
This is the Scene#xrayMaterial.
Public Methods
public createEntity(cfg: Object): Entity source
Creates an Entity within this PerformanceModel, giving it one or more meshes previously created with PerformanceModel#createMesh.
A mesh can only belong to one Entity, so you'll get an error if you try to reuse a mesh among multiple Entitys.
Params:
Name | Type | Attribute | Description |
cfg | Object | Entity configuration. |
|
cfg.id | String | Optional ID for the new Entity. Must not clash with any existing components within the Scene. |
|
cfg.meshIds | String[] | IDs of one or more meshes created previously with {@link PerformanceModel@createMesh}. |
|
cfg.isObject | Boolean |
|
Set |
cfg.visible | Boolean |
|
Indicates if the Entity is initially visible. |
cfg.culled | Boolean |
|
Indicates if the Entity is initially culled from view. |
cfg.pickable | Boolean |
|
Indicates if the Entity is initially pickable. |
cfg.clippable | Boolean |
|
Indicates if the Entity is initially clippable. |
cfg.collidable | Boolean |
|
Indicates if the Entity is initially included in boundary calculations. |
cfg.castsShadow | Boolean |
|
Indicates if the Entity initially casts shadows. |
cfg.receivesShadow | Boolean |
|
Indicates if the Entity initially receives shadows. |
cfg.xrayed | Boolean |
|
Indicates if the Entity is initially xrayed. XRayed appearance is configured by PerformanceModel#xrayMaterial. |
cfg.highlighted | Boolean |
|
Indicates if the Entity is initially highlighted. Highlighted appearance is configured by PerformanceModel#highlightMaterial. |
cfg.selected | Boolean |
|
Indicates if the Entity is initially selected. Selected appearance is configured by PerformanceModel#selectedMaterial. |
cfg.edges | Boolean |
|
Indicates if the Entity's edges are initially emphasized. Edges appearance is configured by PerformanceModel#edgeMaterial. |
public createGeometry(cfg: *) source
Creates a reusable geometry within this PerformanceModel.
We can then supply the geometry ID to PerformanceModel#createMesh when we want to create meshes that instance the geometry.
If provide a positionsDecodeMatrix
, then createGeometry()
will assume
that the positions
and normals
arrays are compressed. When compressed, positions
will be
quantized and in World-space, and normals
will be oct-encoded and in World-space.
Note that positions
, normals
and indices
are all required together.
Params:
Name | Type | Attribute | Description |
cfg | * | Geometry properties. |
|
cfg.id | String | Number | Mandatory ID for the geometry, to refer to with PerformanceModel#createMesh. |
|
cfg.primitive | String | The primitive type. Accepted values are 'points', 'lines', 'triangles', 'solid' and 'surface'. |
|
cfg.positions | Number[] | Flat array of positions. |
|
cfg.normals | Number[] |
|
Flat array of normal vectors. Only used with 'triangles' primitives. When no normals are given, the geometry will be flat shaded using auto-generated face-aligned normals. |
cfg.colors | Number[] |
|
Flat array of RGBA vertex colors as float values in range |
cfg.colorsCompressed | Number[] |
|
Flat array of RGBA vertex colors as unsigned short integers in range |
cfg.indices | Number[] |
|
Array of indices. Not required for |
cfg.edgeIndices | Number[] |
|
Array of edge line indices. Used only for Required for 'triangles' primitives. These are automatically generated internally if not supplied, using the |
cfg.positionsDecodeMatrix | Number[] |
|
A 4x4 matrix for decompressing |
cfg.origin | Number[] |
|
Optional geometry origin, relative to PerformanceModel#origin. When this is given, then every mesh created with PerformanceModel#createMesh that uses this geometry will be transformed relative to this origin. |
public createMesh(cfg: object): * source
Creates a mesh within this PerformanceModel.
A mesh can either share geometry with other meshes, or have its own unique geometry.
To share a geometry with other meshes, provide the ID of a geometry created earlier with PerformanceModel#createGeometry.
To create unique geometry for the mesh, provide geometry data arrays.
Internally, PerformanceModel will batch all unique mesh geometries into the same arrays, which improves rendering performance.
If you accompany the arrays with a positionsDecodeMatrix
, then createMesh()
will assume
that the positions
and normals
arrays are compressed. When compressed, positions
will be
quantized and in World-space, and normals
will be oct-encoded and in World-space.
If you accompany the arrays with an origin
, then createMesh()
will assume
that the positions
are in relative-to-center (RTC) coordinates, with origin
being the origin of their
RTC coordinate system.
When providing either positionsDecodeMatrix
or origin
, createMesh()
will start a new
batch each time either of those two parameters change since the last call. Therefore, to combine arrays into the
minimum number of batches, it's best for performance to create your shared meshes in runs that have the same value
for positionsDecodeMatrix
and origin
.
Note that positions
, normals
and indices
are all required together.
Params:
Name | Type | Attribute | Description |
cfg | object | Object properties. |
|
cfg.id | String | Mandatory ID for the new mesh. Must not clash with any existing components within the Scene. |
|
cfg.geometryId | String | Number |
|
ID of a geometry to instance, previously created with {@link PerformanceModel#createGeometry:method"}}createMesh(){{/crossLink}}. Overrides all other geometry parameters given to this method. |
cfg.primitive | String |
|
Geometry primitive type. Ignored when |
cfg.positions | Number[] |
|
Flat array of vertex positions. Ignored when |
cfg.colors | Number[] |
|
Flat array of RGB vertex colors as float values in range |
cfg.colorsCompressed | Number[] |
|
Flat array of RGB vertex colors as unsigned short integers in range |
cfg.normals | Number[] |
|
Flat array of normal vectors. Only used with 'triangles' primitives. When no normals are given, the mesh will be flat shaded using auto-generated face-aligned normals. |
cfg.positionsDecodeMatrix | Number[] |
|
A 4x4 matrix for decompressing |
cfg.origin | Number[] |
|
Optional geometry origin, relative to PerformanceModel#origin. When this is given, then |
cfg.indices | Number[] |
|
Array of triangle indices. Ignored when |
cfg.edgeIndices | Number[] |
|
Array of edge line indices. If |
cfg.position | Number[] |
|
Local 3D position. of the mesh |
cfg.scale | Number[] |
|
Scale of the mesh. |
cfg.rotation | Number[] |
|
Rotation of the mesh as Euler angles given in degrees, for each of the X, Y and Z axis. |
cfg.matrix | Number[] |
|
Mesh modelling transform matrix. Overrides the |
cfg.color | Number[] |
|
RGB color in range |
cfg.opacity | Number |
|
Opacity in range |
Return:
* |