archive-gh-me/luma.gl

Fork 0

mirror of https://github.com/visgl/luma.gl.git synced 2025-12-08 17:36:19 +00:00

Ib Green eb5f1b3827

@ibgreen chore: v9 doc updates (#1713 )

2022-12-15 11:59:54 -05:00

14 KiB

Raw Blame History

RenderPipeline

The luma.gl v9 API is currently in public review.

A RenderPipeline contains a matched pair of vertex and fragment shaders that can be exectued on the GPU by calling RenderPipeline.draw(). handle compilation and linking of shaders, and store uniform values. They provide draw call which allows the application to run the shaders on specified input data.

A RenderPipeline controls the vertex and fragment shader stages, and can be used in GPURenderPassEncoder as well as GPURenderBundleEncoder.

Render pipeline inputs are:

bindings, according to the given bindingLayout
vertex and index buffers
the color attachments, Framebuffer
the optional depth-stencil attachment, described by Framebuffer
parameters

Render pipeline outputs are:

buffer bindings with a type of "storage"
storageTexture bindings with a access of "write-only"
the color attachments, described by Framebuffer
the depth-stencil optional attachment, described by Framebuffer

A render pipeline is comprised of the following render stages:

Vertex fetch, from the buffers buffers
Vertex shader, props.vs
Primitive assembly, controlled by
Rasterization controlled by parameters (GPUPrimitiveState, GPUDepthStencilState, and GPUMultisampleState)
Fragment shader, controlled by props.fs
Stencil test and operation, controlled by GPUDepthStencilState
Depth test and write, controlled by GPUDepthStencilState
Output merging, controlled by GPUFragmentState.targets

Usage

Creating a pipeline

const pipeline = device.createRenderPipeline({
  id: 'my-pipeline',
  vs: vertexShaderSourceString,
  fs: fragmentShaderSourceString
});

Set or update uniforms, in this case world and projection matrices

pipeline.setUniforms({
  uMVMatrix: view,
  uPMatrix: projection
});

Create a VertexArray to store buffer values for the vertices of a triangle and drawing

const pipeline = device.createRenderPipeline({vs, fs});

const vertexArray = new VertexArray(gl, {pipeline});

vertexArray.setAttributes({
  aVertexPosition: new Buffer(gl, {data: new Float32Array([0, 1, 0, -1, -1, 0, 1, -1, 0])})
});

pipeline.draw({vertexArray, ...});

Creating a pipeline for transform feedback, specifying which varyings to use

const pipeline = device.createRenderPipeline({vs, fs, varyings: ['gl_Position']});

Members

gl : WebGLRenderingContext
handle : WebGLProgram - The WebGL WebGLProgram instance.
id : String - id string for debugging.

Constructor

RenderPipeline(gl : WebGLRenderingContext, props : Object)

Creates a new pipeline using the supplied vertex and fragment shaders. The shaders are compiled into WebGLShaders and is created and the shaders are linked.

const pipeline = device.createRenderPipeline({
  id: 'my-identifier',
  vs: vertexShaderSource,
  fs: fragmentShaderSource,
  varyings: ['gl_Position', 'vColor']
});

id (string, optional) - string id (to help indentify the pipeline during debugging).
vs (VertexShader|String) - A vertex shader object, or source as a string.
fs (FragmentShader|String) - A fragment shader object, or source as a string.
varyings WebGL 2 (String[]) - a list of names of varyings.
bufferMode=GL.SEPARATE_ATTRIBS WebGL 2 (GLenum) - Optional, specifies how transform feedback should store the varyings.

`GL.TRANSFORM_FEEDBACK_BUFFER_MODE`	Description
`GL.SEPARATE_ATTRIBS`	One varying per buffer
`GL.INTERLEAVED_ATTRIBS`	Multiple varyings per buffer

WebGL References WebGLProgram, gl.createProgram

delete() : RenderPipeline

Deletes resources held by pipeline. Note: Does not currently delete shaders (to enable shader caching).

Methods

initialize(props : Object) : RenderPipeline

Relinks a pipeline. Takes the same options as the constructor

setUniforms(uniforms : Object) : RenderPipeline

Sets named uniforms from a map, ignoring names

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 RenderPipeline than its shaders use, the extra uniforms will simply be ignored.
value (mixed) - The value to be set. Can be a float, an array of floats, a typed array, a boolean, Texture etc. The values must match the declarations in the shader.

gl.useProgram

draw(opts) : RenderPipeline

RenderPipeline.draw is the entry point for running shaders, rendering and (optionally calculating data using transform feedback techniques).

  RenderPipeline.draw({
    vertexArray,

    uniforms = {},
    transformFeedback = null,
    samplers = {},
    parameters = {},

    drawMode = GL.TRIANGLES,
    vertexCount,
    offset = 0,
    isIndexed = false,
    indexType = GL.UNSIGNED_SHORT,
    isInstanced = false,
    instanceCount = 0,

    start = 0,
    end=
  })

Main parameters

vertexArray - a VertexArray object that will be bound and unbound before and after the draw call.
uniforms={} - a map of uniforms that will be set just before the draw call (and remain set after the call).
samplers={} - a map of texture Samplers that will be bound before the draw call.
parameters - temporary gl settings to be applied to this draw call.
transformFeedback=null - optional TransformFeedback object containing buffers that will receive the output of the transform feedback operation.

Potentially autodeduced parameters

drawMode=GL.TRIANGLES - geometry primitive format of vertex data
vertexCount - number of vertices to draw
offset=0 - first vertex to draw
isIndexed=false - use indices in the "elements" buffer
indexType=GL.UNSIGNED_SHORT - must match the type of the "elements" buffer
isInstanced=false - Set to enable instanced rendering.
instanceCount=0 - Number of instances

Parameters for drawing a limited range (WebGL 2 only)

start - hint to GPU, activates gl.drawElementsRange (WebGL 2)
end - hint to GPU, activates gl.drawElementsRange (WebGL 2)

Returns: true if successful, false if draw call is blocked due to missing resources.

Notes:

Runs the shaders in the pipeline, on the attributes and uniforms.
Indexed rendering uses the element buffer (GL.ELEMENT_ARRAY_BUFFER), make sure your attributes or VertexArray contains one.
If a TransformFeedback object is supplied, transformFeedback.begin() and transformFeedback.end() will be called before and after the draw call.
A Sampler will only be bound if there is a matching Texture with the same key in the supplied uniforms object.
Once a uniform is set, it's size should not be changed. This is only a concern for array uniforms.

The following WebGL APIs are called in this function:

RenderPipeline

The luma.gl v9 API is currently in public review.

A RenderPipeline contains a matched pair of vertex and fragment shaders that can be exectued on the GPU by calling RenderPipeline.draw(). Programs handle compilation and linking of shaders, and store uniform values. They provide draw call which allows the application to run the shaders on specified input data.

Usage

Creating a pipeline

const pipeline = device.createRenderPipeline({
  id: 'my-pipeline',
  vs: vertexShaderSourceString,
  fs: fragmentShaderSourceString
});

Set or update uniforms, in this case world and projection matrices

pipeline.setUniforms({
  uMVMatrix: view,
  uPMatrix: projection
});

Create a VertexArray to store buffer values for the vertices of a triangle and drawing

const pipeline = device.createRenderPipeline({vs, fs});

const vertexArray = new VertexArray(gl, {pipeline});

vertexArray.setAttributes({
  aVertexPosition: new Buffer(gl, {data: new Float32Array([0, 1, 0, -1, -1, 0, 1, -1, 0])})
});

pipeline.draw({vertexArray, ...});

Creating a pipeline for transform feedback, specifying which varyings to use

const pipeline = device.createRenderPipeline({vs, fs, varyings: ['gl_Position']});

Members

device: Device - holds a reference to the Device that created this Buffer.
handle: unknown - holds the underlying WebGL or WebGPU shader object
props: BufferProps - holds a copy of the BufferProps used to create this Buffer.

Methods

`constructor(props: BufferProps)`

Buffer is an abstract class and cannot be instantiated directly. Create with device.createBuffer(...).

`destroy(): void`

Free up any GPU resources associated with this buffer immediately (instead of waiting for garbage collection).

Members

gl : WebGLRenderingContext
handle : WebGLProgram - The WebGL WebGLProgram instance.
id : String - id string for debugging.

Constructor

RenderPipeline(gl : WebGLRenderingContext, props : Object)

Creates a new pipeline using the supplied vertex and fragment shaders. The shaders are compiled into WebGLShaders and is created and the shaders are linked.

const pipeline = device.createRenderPipeline({
  id: 'my-identifier',
  vs: vertexShaderSource,
  fs: fragmentShaderSource,
  varyings: ['gl_Position', 'vColor']
});

id (string, optional) - string id (to help indentify the pipeline during debugging).
vs (VertexShader|String) - A vertex shader object, or source as a string.
fs (FragmentShader|String) - A fragment shader object, or source as a string.
varyings WebGL 2 (String[]) - a list of names of varyings.
bufferMode=GL.SEPARATE_ATTRIBS WebGL 2 (GLenum) - Optional, specifies how transform feedback should store the varyings.

`GL.TRANSFORM_FEEDBACK_BUFFER_MODE`	Description
`GL.SEPARATE_ATTRIBS`	One varying per buffer
`GL.INTERLEAVED_ATTRIBS`	Multiple varyings per buffer

WebGL References WebGLProgram, gl.createProgram

delete() : RenderPipeline

Deletes resources held by pipeline. Note: Does not currently delete shaders (to enable shader caching).

Methods

initialize(props : Object) : RenderPipeline

Relinks a pipeline. Takes the same options as the constructor

setUniforms(uniforms : Object) : RenderPipeline

Sets named uniforms from a map, ignoring names

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 RenderPipeline than its shaders use, the extra uniforms will simply be ignored.
value (mixed) - The value to be set. Can be a float, an array of floats, a typed array, a boolean, Texture etc. The values must match the declarations in the shader.

gl.useProgram

draw(opts) : RenderPipeline

RenderPipeline.draw is the entry point for running shaders, rendering and (optionally calculating data using transform feedback techniques).

  RenderPipeline.draw({
    vertexArray,

    uniforms = {},
    transformFeedback = null,
    samplers = {},
    parameters = {},

    drawMode = GL.TRIANGLES,
    vertexCount,
    offset = 0,
    isIndexed = false,
    indexType = GL.UNSIGNED_SHORT,
    isInstanced = false,
    instanceCount = 0,

    start = 0,
    end=
  })

Main parameters

vertexArray - a VertexArray object that will be bound and unbound before and after the draw call.
uniforms={} - a map of uniforms that will be set just before the draw call (and remain set after the call).
samplers={} - a map of texture Samplers that will be bound before the draw call.
parameters - temporary gl settings to be applied to this draw call.
transformFeedback=null - optional TransformFeedback object containing buffers that will receive the output of the transform feedback operation.

Potentially autodeduced parameters

drawMode=GL.TRIANGLES - geometry primitive format of vertex data
vertexCount - number of vertices to draw
offset=0 - first vertex to draw
isIndexed=false - use indices in the "elements" buffer
indexType=GL.UNSIGNED_SHORT - must match the type of the "elements" buffer
isInstanced=false - Set to enable instanced rendering.
instanceCount=0 - Number of instances

Parameters for drawing a limited range (WebGL 2 only)

start - hint to GPU, activates gl.drawElementsRange (WebGL 2)
end - hint to GPU, activates gl.drawElementsRange (WebGL 2)

Returns: true if successful, false if draw call is blocked due to missing resources.

Notes:

Runs the shaders in the pipeline, on the attributes and uniforms.
Indexed rendering uses the element buffer (GL.ELEMENT_ARRAY_BUFFER), make sure your attributes or VertexArray contains one.
If a TransformFeedback object is supplied, transformFeedback.begin() and transformFeedback.end() will be called before and after the draw call.
A Sampler will only be bound if there is a matching Texture with the same key in the supplied uniforms object.
Once a uniform is set, it's size should not be changed. This is only a concern for array uniforms.

The following WebGL APIs are called in this function:

Constants

Limits

Limit	Value	Description
`GL.MAX_VERTEX_TEXTURE_IMAGE_UNITS`	>= 0 (GLint)
`GL.MAX_RENDERBUFFER_SIZE`	>= 1 (GLint)
`GL.MAX_VARYING_VECTORS`	>= 8 (GLint)
`GL.MAX_VERTEX_ATTRIBS`	>= 8 (GLint)
`GL.MAX_VERTEX_UNIFORM_VECTORS`	>= 128 (GLint)
`GL.MAX_FRAGMENT_UNIFORM_VECTORS`	>= 16 (GLint)
`GL.TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH` (WebGL 2)	-	-

14 KiB Raw Blame History

RenderPipeline

Usage

Members

Constructor

RenderPipeline(gl : WebGLRenderingContext, props : Object)

delete() : RenderPipeline

Methods

initialize(props : Object) : RenderPipeline

setUniforms(uniforms : Object) : RenderPipeline

draw(opts) : RenderPipeline

RenderPipeline

Usage

Members

Methods

constructor(props: BufferProps)

destroy(): void

Members

Constructor

RenderPipeline(gl : WebGLRenderingContext, props : Object)

delete() : RenderPipeline

Methods

initialize(props : Object) : RenderPipeline

setUniforms(uniforms : Object) : RenderPipeline

draw(opts) : RenderPipeline

Constants

Limits

14 KiB

Raw Blame History

`constructor(props: BufferProps)`

`destroy(): void`