luma.gl/docs/api-reference/core/model.md

Model

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.

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

• 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.

Usage

Set matrix information for the projection matrix and element matrix of the camera and world.

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

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

2. opts.vs (VertexShader|string) - A vertex shader object, or source as a string.
3. opts.fs (FragmentShader|string) - A fragment shader object, ot source as a string.
4. opts.shaderCache (ShaderCache|null) - An optional ShaderCache, will be used to compile shader source strings.

• 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.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.

Model.setInstanceCount

• instanceCount

instanceCount is used during draw and render

Model.getInstanceCount

Returns the current instanceCount

Model.setVertexCount

• vertexCount.

vertexCount is used during draw and render

Model.getVertexCount

Model.isPickable

• Unused

Model.setPickable

• Unused

Model.getProgram

Returns the program set on the model if any

Model.getGeometry

Returns the geometry set on the model if any

Model.getAttributes

Returns the attributes set on the model if any

Model.setAttributes

• sets a number of attributes

Model.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.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.draw

• uniforms
• attributes
• settings
• samplers

Model.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

Model.onBeforeRender()

Callback before render, can be used to adust settings that affect the draw call. It is recommended to use parameters on render instead.

Model.onAfterRender()

Callback after render, can be used to adust settings that affect the draw call. It is recommended to use parameters on render instead.

Model.setProgramState

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

Model.unsetProgramState

Reverses setProgramState