WorldWind: Class: SkyProgram

Constructor

new SkyProgram(gl)

Constructs a new program. Initializes, compiles and links this GLSL program with the source code for its vertex and fragment shaders.

This method creates WebGL shaders for the program's shader sources and attaches them to a new GLSL program. This method then compiles the shaders and then links the program if compilation is successful. Use the bind method to make the program current during rendering.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.

Source:

shaders/SkyProgram.js, line 41

Throws:

If the shaders cannot be compiled, or linking of the compiled shaders into a program fails.
Type ArgumentError

Extends

AtmosphereProgram

Members

(static, readonly) key :string

A string that uniquely identifies this program.

Type:

string

Source:

shaders/SkyProgram.js, line 190

altitude :Number

The globe's atmosphere altitude.

Type:

Number

Inherited From:

AtmosphereProgram#altitude

Default Value:

160000.0 meters

Source:

shaders/AtmosphereProgram.js, line 61

(readonly) atmosphereRadius2Location :WebGLUniformLocation

The WebGL location for this program's 'atmosphereRadius2' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#atmosphereRadius2Location

Source:

shaders/AtmosphereProgram.js, line 138

(readonly) atmosphereRadiusLocation :WebGLUniformLocation

The WebGL location for this program's 'atmosphereRadius' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#atmosphereRadiusLocation

Source:

shaders/AtmosphereProgram.js, line 131

(readonly) eyeMagnitude2Location :WebGLUniformLocation

The WebGL location for this program's 'eyeMagnitude2' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#eyeMagnitude2Location

Source:

shaders/AtmosphereProgram.js, line 117

(readonly) eyeMagnitudeLocation :WebGLUniformLocation

The WebGL location for this program's 'eyeMagnitude' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#eyeMagnitudeLocation

Source:

shaders/AtmosphereProgram.js, line 110

(readonly) eyePointLocation :WebGLUniformLocation

The WebGL location for this program's 'eyePoint' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#eyePointLocation

Source:

shaders/AtmosphereProgram.js, line 103

(readonly) fragModeLocation :WebGLUniformLocation

The WebGL location for this program's 'fragMode' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#fragModeLocation

Source:

shaders/AtmosphereProgram.js, line 75

(readonly) globeRadiusLocation :WebGLUniformLocation

The WebGL location for this program's 'globeRadius' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#globeRadiusLocation

Source:

shaders/AtmosphereProgram.js, line 145

(readonly) lightDirectionLocation :WebGLUniformLocation

The WebGL location for this program's 'lightDirection' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#lightDirectionLocation

Source:

shaders/AtmosphereProgram.js, line 124

(readonly) mvpMatrixLocation :WebGLUniformLocation

The WebGL location for this program's 'mvpMatrix' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#mvpMatrixLocation

Source:

shaders/AtmosphereProgram.js, line 82

(readonly) programId :WebGLProgram

Indicates the WebGL program object associated with this GPU program.

Type:

WebGLProgram

Inherited From:

GpuProgram#programId

Source:

shaders/GpuProgram.js, line 111

rayleighScaleDepth :Number

This atmosphere's Rayleigh scale depth.

Type:

Number

Inherited From:

AtmosphereProgram#rayleighScaleDepth

Default Value:

0.25

Source:

shaders/AtmosphereProgram.js, line 68

(readonly) scaleDepthLocation :WebGLUniformLocation

The WebGL location for this program's 'scaleDepth' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#scaleDepthLocation

Source:

shaders/AtmosphereProgram.js, line 159

(readonly) scaleLocation :WebGLUniformLocation

The WebGL location for this program's 'scale' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#scaleLocation

Source:

shaders/AtmosphereProgram.js, line 152

(readonly) scaleOverScaleDepthLocation :WebGLUniformLocation

The WebGL location for this program's 'scaleOverScaleDepth' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#scaleOverScaleDepthLocation

Source:

shaders/AtmosphereProgram.js, line 166

(readonly) texCoordMatrixLocation :WebGLUniformLocation

The WebGL location for this program's 'texCoordMatrix' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#texCoordMatrixLocation

Source:

shaders/AtmosphereProgram.js, line 89

(readonly) vertexOriginLocation :WebGLUniformLocation

The WebGL location for this program's 'vertexOrigin' uniform.

Type:

WebGLUniformLocation

Inherited From:

AtmosphereProgram#vertexOriginLocation

Source:

shaders/AtmosphereProgram.js, line 96

Methods

attributeLocation(gl, attributeName) → {Number}

Returns the GLSL attribute location of a specified attribute name.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`attributeName`	String	The name of the attribute whose location is determined.

Inherited From:

GpuProgram#attributeLocation

Source:

shaders/GpuProgram.js, line 172

Throws:

If the specified attribute name is null, empty or undefined.
Type ArgumentError

Returns:

The WebGL attribute location of the specified attribute, or -1 if the attribute is not found.

Type: Number

dispose(gl)

Releases this GPU program's WebGL program and associated shaders. Upon return this GPU program's WebGL program ID is 0 as is that of the associated shaders.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.

Inherited From:

GpuProgram#dispose

Source:

shaders/GpuProgram.js, line 136

getAltitude() → {Number}

Returns the atmosphere's altitude.

Inherited From:

AtmosphereProgram#getAltitude

Source:

shaders/AtmosphereProgram.js, line 185

Returns:

The atmosphere's altitude in meters.

Type: Number

(protected) link(gl, program) → {Boolean}

Links a specified GLSL program. This method is not meant to be called by applications. It is called internally as needed.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`program`	WebGLProgram	The WebGL program.

Inherited From:

GpuProgram#link

Source:

shaders/GpuProgram.js, line 220

Returns:

true if linking was successful, otherwise false.

Type: Boolean

loadEyePoint(gl, vector)

Loads the specified vector as the value of this program's 'lightDirection' uniform variable, the magnitude's specified vector as the value of this program's 'eyeMagnitude' uniform variable and the squared magnitude's specified vector as the value of this program's 'eyeMagnitude2' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`vector`	Vec3	The vector to load.

Inherited From:

AtmosphereProgram#loadEyePoint

Source:

shaders/AtmosphereProgram.js, line 263

Throws:

If the specified vector is null or undefined.
Type ArgumentError

loadFragMode(gl, fragMode)

Loads the specified number as the value of this program's 'fragMode' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`fragMode`	Number	The frag mode value.

Inherited From:

AtmosphereProgram#loadFragMode

Source:

shaders/AtmosphereProgram.js, line 196

Throws:

If the specified number is null or undefined.
Type ArgumentError

loadGlobeRadius(gl, globeRadius)

Loads the specified number as the value of this program's 'globeRadius' uniform variable and the specified number which add the altitude value as the value of this program's 'atmosphereRadius' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`globeRadius`	Number	The globe radius value.

Inherited From:

AtmosphereProgram#loadGlobeRadius

Source:

shaders/AtmosphereProgram.js, line 282

Throws:

If the specified number is null or undefined.
Type ArgumentError

loadLightDirection(gl, vector)

Loads the specified vector as the value of this program's 'lightDirection' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`vector`	Vec3	The vector to load.

Inherited From:

AtmosphereProgram#loadLightDirection

Source:

shaders/AtmosphereProgram.js, line 245

Throws:

If the specified vector is null or undefined.
Type ArgumentError

loadModelviewProjection(gl, matrix)

Loads the specified matrix as the value of this program's 'mvpMatrix' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`matrix`	Matrix	The matrix to load.

Inherited From:

AtmosphereProgram#loadModelviewProjection

Source:

shaders/AtmosphereProgram.js, line 212

Throws:

If the specified matrix is null or undefined.
Type ArgumentError

loadTexMatrix(gl, matrix)

Loads the specified matrix as the value of this program's 'texCoordMatrix' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`matrix`	Matrix3	The texture coordinate matrix.

Inherited From:

AtmosphereProgram#loadTexMatrix

Source:

shaders/AtmosphereProgram.js, line 313

loadUniformColor(gl, color, location)

Loads a specified color as the value of a GLSL vec4 uniform variable with the specified location.

This function multiplies the red, green and blue components by the alpha component prior to loading the color in the GLSL uniform variable, but does not modify the specified color.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`color`	Color	The color to load.
`location`	WebGLUniformLocation	The location of the uniform variable in the currently bound GLSL program.

Inherited From:

GpuProgram#loadUniformColor

Source:

shaders/GpuProgram.js, line 258

Throws:

If the specified color is null or undefined.
Type ArgumentError

loadUniformColorComponents(gl, red, green, blue, alpha, location)

Loads the specified RGBA color components as the value of a GLSL vec4 uniform variable with the specified location.

This function multiplies the red, green and blue components by the alpha component prior to loading the color in the GLSL uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`red`	Number	The red component, a number between 0 and 1.
`green`	Number	The green component, a number between 0 and 1.
`blue`	Number	The blue component, a number between 0 and 1.
`alpha`	Number	The alpha component, a number between 0 and 1.
`location`	WebGLUniformLocation	The location of the uniform variable in the currently bound GLSL program.

Inherited From:

GpuProgram#loadUniformColorComponents

Source:

shaders/GpuProgram.js, line 282

loadUniformMatrix(gl, matrix, location)

Loads a specified matrix as the value of a GLSL 4x4 matrix uniform variable with the specified location.

This functions converts the matrix into column-major order prior to loading its components into the GLSL uniform variable, but does not modify the specified matrix.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`matrix`	Matrix	The matrix to load.
`location`	WebGLUniformLocation	The location of the uniform variable in the currently bound GLSL program.

Inherited From:

GpuProgram#loadUniformMatrix

Source:

shaders/GpuProgram.js, line 237

Throws:

If the specified matrix is null or undefined.
Type ArgumentError

loadVertexOrigin(gl, vector)

Loads the specified vector as the value of this program's 'vertexOrigin' uniform variable.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`vector`	Vec3	The vector to load.

Inherited From:

AtmosphereProgram#loadVertexOrigin

Source:

shaders/AtmosphereProgram.js, line 229

Throws:

If the specified vector is null or undefined.
Type ArgumentError

setScale(gl)

Sets the program's 'scale', 'scaleDepth' and 'scaleOverScaleDepth' uniform variables.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.

Inherited From:

AtmosphereProgram#setScale

Source:

shaders/AtmosphereProgram.js, line 302

uniformLocation(gl, uniformName) → {WebGLUniformLocation}

Returns the GLSL uniform location of a specified uniform name.

Parameters:

Name	Type	Description
`gl`	WebGLRenderingContext	The current WebGL context.
`uniformName`	String	The name of the uniform variable whose location is determined.

Inherited From:

GpuProgram#uniformLocation

Source:

shaders/GpuProgram.js, line 196

Throws:

If the specified uniform name is null, empty or undefined.
Type ArgumentError

Returns:

The WebGL uniform location of the specified uniform variable, or -1 if the uniform is not found.

Type: WebGLUniformLocation