luma.gl/docs/model.md

layout	title	categories
docs	Model	Documentation

The Model class holds all the data necessary to draw an object in luma.gl: shaders (via a Program instance), vertex attributes (a Geometry instance), uniforms and textures.

Class: Model

For most applications, the Model class is probably the most central luma.gl class.

Model Overview:

• Model is a subclass of Object3D, meaning that it can be used in scene graphs (by adding it to a Group or a Scene), and it can be positioned, rotated and scaled.
• Model contains a Program (the shaders), a Geometry (containing the attributes for the primitive), any additional attributes for instanced rendering, and also stores textures and uniforms.
• Has simple boolean flags for selecting indexed and/or instanced rendering.
• Offers a simple render method that binds all attributes, uniforms and textures, selects (uses) the program, and calls the right gl draw call for the model.
• Setting buffers
• Setting textures and more.

Remarks

• All instance methods in Model are chainable (unless they return a documented value).

Methods

| Method | Description | |====|====| | constructor | creates a Model| | hash | Return a "unique" integer | | setInstanceCount | How many instances | | getInstanceCount | Defaults to 0 | | setVertexCount | How many vertices, can be autocalculated from Geometry | | getVertexCount | Gets vertex count | | isPickable | True if picking is enabled | | setPickable | enable/disable picking| | getProgram | Get model's Program instance | | getGeometry | Get model's Geometry instance | | getAttributes | Get a map of named attributes | | setAttributes | Sets map of attributes (Arrays or buffers) | | getUniforms | Returns map of currently stored uniforms | | setUniforms | Stores named uniforms {key, value} | | setTextures | Sets array of textures for model | | render | Takes a camera or a viewMatrix parameter | | onBeforeRender | Called before model renders | | onAfterRender | Called after model renders | | setProgramState | Sets uniforms, attributes, textures, uses program | | unsetProgramState | Unbinds attributes etc | | bindTextures | binds textures |

Model constructor

• program
• geometry
• material = null
• textures = []
• instanced = false
• instanceCount = 0
• vertexCount = undefined
• isIndexed = undefined
• pickable = false, pick = null
• uniforms = {}
• attributes = {}
• render = null
• onBeforeRender = null
• onAfterRender = null

Model Method: setUniforms

For each key, value of the object passed in it executes setUniform(key, value).

Syntax:

program.setUniforms(object);

Arguments:

1. object - (object) An object with key value pairs matching a uniform name and its value respectively.

2. key - (string) The name of the uniform to be set. The name of the uniform will be matched with the name of the uniform declared in the shader. You can set more uniforms on the Model than its shaders use, the extra uniforms will simply be ignored.

3. value - (mixed) The value to be set. Can be a float, an array of floats, a boolean, etc. When the shaders are run (through a draw call), The must match the declaration. There's no need to convert arrays into a typed array, that's done automatically.

Examples:

Set matrix information for the projection matrix and element matrix of the camera and world. The context of this example can be seen [here]http://uber.github.io/luma.gl/examples/lessons/3/).

{% highlight js %} program.setUniforms({ 'uMVMatrix': view, 'uPMatrix': camera.projection }); {% endhighlight %}

Model Method: setTexture

Model Method: setTextures

Sets a number of textures on the program.

Model accessor get hash

Model method setInstanceCount

• instanceCount

Model method getInstanceCount

Model method setVertexCount

• vertexCount

Model method getVertexCount

Model method isPickable

Model method setPickable

Model method getProgram

Model method getGeometry

Model method getAttributes

Model method setAttributes

• attributes = {}

Model method getUniforms

Sets uniforms to be used. Note that uniforms are stored in a map so uniform values not present in the argument map won't be overwritten.

Model method setUniforms

Sets uniforms to be used. Note that uniforms are stored in a map so uniform values not present in the argument map won't be overwritten.

Model method setTextures

Sets textures to be used.

Model method render

Draws the model (i.e. binds all the attributes textures and uniforms and runs the shaders in attached program). Can be called directly but is usually called during by Scene.render traversing the models in the scene.

• camera - Camera exposes uniforms that can be used directly in shaders
• viewMatrix

Less commonly used methods

Model method onBeforeRender()

Attaches attributes

Model method onAfterRender()

Detaches attributes

Model method setProgramState

Attaches attributes for primitive (from geometry) and instances (from model), Sets uniforms and textures

Model method unsetProgramState

Reverses setProgramState

Model method bindTextures

(force = false)