Class ShaderEmitter

java.lang.Object

com.codename1.gpu.shader.ShaderEmitter

public final class ShaderEmitter
extends Object

Prints ShaderNode graphs as statements of one shading language. This is the part of a backend's shader generator that custom materials need; applications do not call it.

A backend creates one emitter per shader stage, calls emit for each hook it splices in, and uses the returned expression where the engine's own value would have gone. Every node that is not a constant or an input becomes one temporary, so a node shared by several hooks is computed once.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ShaderEmitter.Dialect	The shading languages a graph prints as.
static interface	ShaderEmitter.Inputs	Supplies the backend's spelling of the inputs a graph reads.

Constructor Summary

Constructors

Constructor	Description
ShaderEmitter(ShaderEmitter.Dialect dialect, ShaderMaterial material, ShaderEmitter.Inputs inputs, StringBuilder out, String indent, String prefix)	Creates an emitter that appends statements to out.

Method Summary

Modifier and Type	Method	Description
static void	describe(ShaderNode root, StringBuilder sb)	Appends a structural description of a graph: equal for two graphs that print the same program.
String	emit(ShaderNode node)	Declares whatever temporaries node needs and returns the expression that holds its value.
static String	literal(float v)	Returns a float literal every dialect reads the same way.
static String	typeName(ShaderEmitter.Dialect d, ShaderType t)	Returns a dialect's name of a type.
String	typeName(ShaderType t)	Returns the dialect's name of a type.
static boolean	uses(ShaderMaterial material, boolean fragment, String builtin)	Returns true if any hook of the given stage reads the built-in input.
static boolean	uses(ShaderMaterial material, String builtin)	Returns true if any hook of either stage reads the built-in input.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ShaderEmitter

public ShaderEmitter(ShaderEmitter.Dialect dialect,
 ShaderMaterial material,
 ShaderEmitter.Inputs inputs,
 StringBuilder out,
 String indent,
 String prefix)

Creates an emitter that appends statements to out.

Parameters

• dialect: the language to print

• material: the material whose uniforms and textures the graphs read

• inputs: the backend's spelling of the inputs

• out: where the temporaries are declared

• indent: the indentation of each statement

• prefix: a prefix for temporary names, distinct per stage

Method Details

emit

public String emit(ShaderNode node)

Declares whatever temporaries node needs and returns the expression that holds its value.

Parameters

• node: the graph

Returns

an expression of the node's type

literal

public static String literal(float v)

Returns a float literal every dialect reads the same way.

Parameters

• v: a finite value

Returns

the literal

typeName

public String typeName(ShaderType t)

Returns the dialect's name of a type.

Parameters

• t: the type

Returns

the type name

typeName

public static String typeName(ShaderEmitter.Dialect d,
 ShaderType t)

Returns a dialect's name of a type.

Parameters

• d: the dialect

• t: the type

Returns

the type name

uses

public static boolean uses(ShaderMaterial material,
 boolean fragment,
 String builtin)

Returns true if any hook of the given stage reads the built-in input.

Parameters

• material: the material, or null

• fragment: true for the fragment stage

• builtin: the built-in's name, such as worldPos

Returns

true if it is read

uses

public static boolean uses(ShaderMaterial material,
 String builtin)

Returns true if any hook of either stage reads the built-in input.

Parameters

• material: the material, or null

• builtin: the built-in's name

Returns

true if it is read

describe

public static void describe(ShaderNode root,
 StringBuilder sb)

Appends a structural description of a graph: equal for two graphs that print the same program. Shared nodes are written once and then referred to by number.

Parameters

• root: the graph

• sb: where to append