org.achtern.AchternEngine.core.resource.fileparser

Class GLSLParser

java.lang.Object

org.achtern.AchternEngine.core.resource.fileparser.VariableBasedLanguageParser

org.achtern.AchternEngine.core.resource.fileparser.GLSLParser

All Implemented Interfaces:

LineBasedParser

public class GLSLParser
extends VariableBasedLanguageParser
implements LineBasedParser

A custom GLSL pre-parser. Currently supporting #include directives and various build in parsers

Field Summary

Fields

Modifier and Type	Field and Description
static String	CUSTOM_TOKEN_IMPORT CUSTOM TOKEN.
static String	CUSTOM_TOKEN_INCLUDE CUSTOM TOKEN.
static String	INCLUDE_DIRECTORY The parser will look into this directory, in order to include files.
static org.slf4j.Logger	LOGGER
static String	TOKEN_ATTRIBUTE The attribute token used in the GLSL language (attribute type name)
static String	TOKEN_END_STATEMENT The character used to end a line or a statement.
static String	TOKEN_SINGLE_LINE_COMMENT
static String	TOKEN_SPACE Just a space character to safe some memory, when generating code.
static String	TOKEN_STRUCT The struct token used in the GLSL language (struct name {...})
static String	TOKEN_UNIFORM The uniform token used in the GLSL language (uniform type name)

Constructor Summary

Constructors

Constructor and Description
GLSLParser()

Method Summary

Methods

Modifier and Type	Method and Description
static List<String>	expandUniform(Variable uniform, GLSLStruct main, List<GLSLStruct> structs) Expand a uniform If a uniform's type is a custom struct, OpenGL expects you to expand it.
static List<String>	expendVariable(Variable variable, GLSLStruct main, List<GLSLStruct> structs) Expand a variable If a uniform's type is a custom struct, OpenGL expects you to expand it.
protected static List<Variable>	filterPrimitives(List<Variable> variables) Just iterates over the list and adds primitves to a new list
protected static GLSLStruct	findNameInList(String name, List<GLSLStruct> structs) Just iterates over the list and returns the first one with a matching name.
List<Variable>	getAttributes(String text) Just a wrapper for getVariables(text, TOKEN_ATTRIBUTE);
List<Uniform>	getExpandedUniforms(String text, List<Variable> uniforms, List<GLSLStruct> structs) Expands all uniforms for adding to the shader programm
List<GLSLStruct>	getStructs(String text) Parses all structs out of the supplied shader source
static List<Variable>	getVariables(String text, String token) Scans through the shader source and extracts variables which are "flagged" with a specific token.
protected static boolean	isPrimitive(Variable v) Check if the given variable is primitiv.
String	parse(String line) GLSLParser currently only works on include statements
protected static void	printStructs(List<GLSLStruct> structs) Prints a list of GLSLStruct s in an XML like format: (Only if trace logging is enabled!)
GLSLScript	process(GLSLScript script) Processes a GLSLScript.

Methods inherited from class org.achtern.AchternEngine.core.resource.fileparser.VariableBasedLanguageParser

getNames, getTypes

Methods inherited from class java.lang.Object

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

Field Detail

LOGGER

public static final org.slf4j.Logger LOGGER

CUSTOM_TOKEN_INCLUDE

public static final String CUSTOM_TOKEN_INCLUDE

CUSTOM TOKEN. NOT PART OF THE GLSL LANGUAGE! #include MUST be first statement in the line Any two characters after that are allowed. The 3rd character after '#include' has to be part of the filename. The rest of the line will get treated as the filename, BUT the last character! (Trailing whitespaces will get trimmed automatically!) It is advised to stick with either '<' or '"' as delimiter because the parser might switch to regex based parsing. Example: #include "file.ext" // or #include // or even #include $file.ext$ // You could also use two spaces..

See Also:

Constant Field Values

CUSTOM_TOKEN_IMPORT

public static final String CUSTOM_TOKEN_IMPORT

CUSTOM TOKEN. NOT PART OF THE GLSL LANGUAGE! #import MUST be first statement in the line Is at this point the same as include, but behaviour might change soon. Should be used for .glib files!

See Also:

CUSTOM_TOKEN_INCLUDE, Constant Field Values

TOKEN_SPACE

public static final String TOKEN_SPACE

Just a space character to safe some memory, when generating code. Nothing special... Content: " " (one space)

See Also:

Constant Field Values

TOKEN_UNIFORM

public static final String TOKEN_UNIFORM

The uniform token used in the GLSL language (uniform type name)

See Also:

Constant Field Values

TOKEN_ATTRIBUTE

public static final String TOKEN_ATTRIBUTE

The attribute token used in the GLSL language (attribute type name)

See Also:

Constant Field Values

TOKEN_STRUCT

public static final String TOKEN_STRUCT

The struct token used in the GLSL language (struct name {...})

See Also:

Constant Field Values

TOKEN_END_STATEMENT

public static final String TOKEN_END_STATEMENT

The character used to end a line or a statement. vec3 name = vec3(...);

See Also:

Constant Field Values

TOKEN_SINGLE_LINE_COMMENT

public static final String TOKEN_SINGLE_LINE_COMMENT

See Also:

Constant Field Values

INCLUDE_DIRECTORY

public static final String INCLUDE_DIRECTORY

The parser will look into this directory, in order to include files. Vertex Shader: shaders/shader.gvs Random Header File: shaders/include/head.gh Vertex Source: #include "head.gh" ---- This will work!

See Also:

Constant Field Values

Constructor Detail

GLSLParser

public GLSLParser()

Method Detail

parse

public String parse(String line)
             throws Exception

GLSLParser currently only works on include statements

Specified by:

parse in interface LineBasedParser

Parameters:

line - The line to load

Returns:

The parsed line

Throws:

Exception

See Also:

LineBasedParser.parse(String)

getStructs

public List<GLSLStruct> getStructs(String text)

Parses all structs out of the supplied shader source

Parameters:

text - shader source

Returns:

List of found GLSLStructs

process

public GLSLScript process(GLSLScript script)

Processes a GLSLScript. Adds uniforms, expanded uniforms, attributes and all structs in the source. Marks script as processed via GLSLScript#setProcessed(boolean)

Parameters:

script - The script to process

Returns:

The same object as script

getExpandedUniforms

public List<Uniform> getExpandedUniforms(String text,
                                List<Variable> uniforms,
                                List<GLSLStruct> structs)

Expands all uniforms for adding to the shader programm

Parameters:

text - shader source

uniforms - List of uniforms

structs - A list of GLSLStructs

Returns:

List of expanded Uniforms

getAttributes

public List<Variable> getAttributes(String text)

Just a wrapper for getVariables(text, TOKEN_ATTRIBUTE);

Parameters:

text - Shader source

Returns:

List of attribute variables

getVariables

public static List<Variable> getVariables(String text,
                          String token)

Scans through the shader source and extracts variables which are "flagged" with a specific token. For example: source = """ TOKEN type identifyer; ANOTHERTOKEN type identifyer2; TOKEN anothertype identifyer3; """ A call to this method with the arguments - source - "TOKEN" will return a List of 2 Variable objects. Variable{name="identifyer", type="type"} Variable{name="identifyer3", type="anothertype"}

Parameters:

text - Shader source

token - The token which will be used to filter statements of variables.

Returns:

List of variables

expandUniform

public static List<String> expandUniform(Variable uniform,
                         GLSLStruct main,
                         List<GLSLStruct> structs)

Expand a uniform If a uniform's type is a custom struct, OpenGL expects you to expand it. This method is a wrapper for expandVariable, but with debug statements (if TRACE is enabled) Example: struct Foo { float var; float another; } uniform Foo fooU; fooU should be expanded to - fooU.var - fooU.another

Parameters:

uniform - The uniform to expand

main - The main struct (top-level) of the uniform

structs - A list of GLSLStructs

Returns:

List of expanded uniforms

expendVariable

public static List<String> expendVariable(Variable variable,
                          GLSLStruct main,
                          List<GLSLStruct> structs)

Expand a variable If a uniform's type is a custom struct, OpenGL expects you to expand it. Example: struct Foo { float var; float another; } Foo fooU; fooU should be expanded to - fooU.var - fooU.another

Parameters:

variable - The uniform to expand

main - The main struct (top-level) of the uniform

structs - A list of GLSLStructs

Returns:

List of expanded uniforms

filterPrimitives

protected static List<Variable> filterPrimitives(List<Variable> variables)

Just iterates over the list and adds primitves to a new list

Parameters:

variables - All variables

Returns:

The new list with all primitves from the variables list

isPrimitive

protected static boolean isPrimitive(Variable v)

Check if the given variable is primitiv. This is a very cheap detection, but should work in most cases if not, than someone is not following coding conventions and I hate this person anyway... So who cares?! (No really, I'll fix this someday)

Parameters:

v - The variable to check

Returns:

Whether the variable is a primitive

findNameInList

protected static GLSLStruct findNameInList(String name,
                        List<GLSLStruct> structs)

Just iterates over the list and returns the first one with a matching name. Nothing special...

Parameters:

name - The name to search for

structs - A list of GLSLStructs

Returns:

The struct with a matching name | null if not found

printStructs

protected static void printStructs(List<GLSLStruct> structs)

Prints a list of GLSLStruct s in an XML like format: (Only if trace logging is enabled!) Struct Foo { float x; vec4 y; }; will yield x y

Parameters:

structs - A list of GLSLStructs to print