2. General tools

This chapter describes the general commands and options that can be used in Gmsh's ASCII text input files. By "general", we mean "not specifically related to one of the geometry, mesh, solver or post-processing modules". Commands peculiar to these modules will be introduced in 3. Geometry module, 4. Mesh module, 5. Solver module, and 6. Post-processing module, respectively.

Note that, if you are just beginning to use Gmsh, or just want to see what Gmsh is all about, you really don't need to read this chapter and the four next ones. Just have a quick look at 8. Running Gmsh, and go play with the graphical user interface, running the tutorials and demonstration files bundled in the distribution! Most of the commands and options described in the following chapters are available interactively in the GUI, so you don't need to worry about Gmsh's internals for creating your first geometries, meshes and post-processing plots. Once you master the tutorial (read the source files: they are heavily commented--see 7. Tutorial), you might want to come back here to learn more about the specific syntax of Gmsh's commands and esoteric options.

2.1 Expressions
2.2 Operators
2.3 Built-in functions
2.4 User-defined functions
2.5 Loops and conditionals
2.6 General commands
2.7 General options

2.1 Expressions

The two constant types used in Gmsh are real and string (there is no integer type). These types have the same meaning and syntax as in the C or C++ programming languages.

2.1.1 Floating point expressions
2.1.2 Character expressions
2.1.3 Color expressions

2.1.1 Floating point expressions

Floating point expressions (or, more simply, "expressions") are denoted by the metasyntactic variable expression (remember the definition of the syntactic rules in 1.7 Syntactic rules used in this document), and are evaluated during the parsing of the data file:

expression: real | string | string [ expression ] | # string [ ] | ( expression ) | operator-unary-left expression | expression operator-unary-right | expression operator-binary expression | expression operator-ternary-left expression operator-ternary-right expression | built-in-function | real-option | GetValue("string", expression)

Such expressions are used in most of Gmsh's commands. The third and fourth cases in this definition permit to extract one item from a list (see below) and get the size of a list, respectively. The operators operator-unary-left, operator-unary-right, operator-binary, operator-ternary-left and operator-ternary-right are defined in 2.2 Operators. For the definition of built-in-functions, see 2.3 Built-in functions. The various real-options are listed in 2.7 General options, 3.2 Geometry options, 4.3 Mesh options, 5.1 Solver options, and 6.3 Post-processing options.

The last case in the definition allows to ask the user for a value interactively. For example, inserting GetValue("Value of parameter alpha?", 5.76) in an input file will query the user for the value of a certain parameter alpha, assuming the default value is 5.76. If the option General.NoPopup is set (see section 2.7 General options), no question is asked and the default value is automatically used.

List of expressions are also widely used, and are defined as:

expression-list: expression-list-item <, expression-list-item> ...

with

expression-list-item: expression | expression : expression | expression : expression : expression | string [ ] | string [ { expression-list } ] | Point { expression } | transform | extrude

The second case in this last definition permits to create a list containing the range of numbers comprised between two expressions, with a unit incrementation step. The third case also permits to create a list containing the range of numbers comprised between two expressions, but with a positive or negative incrementation step equal to the third expression. The fourth case permits to reference an expression list. The fifth case permits to reference an expression sublist (whose elements are those corresponding to the indices provided by the expression-list). The sixth case permits to retrieve the coordinates of a given geometry point (see section 3.1.1 Points). The last two cases permit to retrieve the indices of entities created through geometrical transformations and extrusions (see 3.1.6 Transformations, and 3.1.5 Extrusions).

To see the practical use of such expressions, have a look at the first couple of examples in 7. Tutorial. Note that, in order to lighten the syntax, you can always omit the braces {} enclosing an expression-list if this expression-list only contains a single item. Also note that a braced expression-list can be preceded by a minus sign in order to change the sign of all the expression-list-items.

2.1.2 Character expressions

Character expressions are defined as:

char-expression: "string" | Today | StrPrefix ( char-expression ) | StrRelative ( char-expression ) | StrCat ( char-expression , char-expression ) | Sprintf ( char-expression , expression-list ) | Sprintf ( char-expression ) Sprintf ( char-option )

The third and fourth cases in this definition permit to take the prefix (e.g. to remove the extension) or the relative path of a string. The fifth case permits to concatenate two character expressions, and the sixth and seventh are equivalent to the sprintf C function (where char-expression is a format string that can contain floating point formatting characters: %e, %g, etc.). The last case permits to use the value of a char-option as a char-expression. The various char-options are listed in 2.7 General options, 3.2 Geometry options, 4.3 Mesh options, 5.1 Solver options, and 6.3 Post-processing options.

Character expressions are mostly used to specify non-numeric options and input/output file names. See 7.8 `t8.geo', for an interesting usage of char-expressions in an animation script.

2.1.3 Color expressions

Colors expressions are hybrids between fixed-length braced expression-lists and strings:

color-expression: string | { expression, expression, expression } | { expression, expression, expression, expression } | color-option

The first case permits to use the X Windows names to refer to colors, e.g., Red, SpringGreen, LavenderBlush3, ... (see `Common/Colors.h' in Gmsh's source tree for a complete list). The second case permits to define colors by using three expressions to specify their red, green and blue components (with values comprised between 0 and 255). The third case permits to define colors by using their red, green and blue color components as well as their alpha channel. The last case permits to use the value of a color-option as a color-expression. The various color-options are listed in 2.7 General options, 3.2 Geometry options, 4.3 Mesh options, 5.1 Solver options, and 6.3 Post-processing options.

See 7.3 `t3.geo', for an example of the use of color expressions.

2.2 Operators

Gmsh's operators are similar to the corresponding operators in C and C++. Here is the list of the unary, binary and ternary operators currently implemented.

operator-unary-left:

-

Unary minus.

!

Logical not.

operator-unary-right:

++

Post-incrementation.

--

Post-decrementation.

operator-binary:

^

Exponentiation.

*

Multiplication.

/

Division.

%

Modulo.

+

Addition.

-

Subtraction.

==

Equality.

!=

Inequality.

>

Greater.

>=

Greater or equality.

<

Less.

<=

Less or equality.

&&

Logical `and'.

||

Logical `or'. (Warning: the logical `or' always implies the evaluation of both arguments. That is, unlike in C or C++, the second operand of || is evaluated even if the first one is true).

operator-ternary-left:

?

:

The only ternary operator, formed by operator-ternary-left and operator-ternary-right, returns the value of its second argument if the first argument is non-zero; otherwise it returns the value of its third argument.

The evaluation priorities are summarized below(3) (from stronger to weaker, i.e., * has a highest evaluation priority than +). Parentheses () may be used anywhere to change the order of evaluation:

1. (), [], ., #
2. ^
3. !, ++, --, - (unary)
4. *, /, %
5. +, -
6. <, >, <=, >=
7. ==, !=
8. &&
9. ||
10. ?:
11. =, +=, -=, *=, /=

2.3 Built-in functions

A built-in function is composed of an identifier followed by a pair of parentheses containing an expression-list (the list of its arguments)(4). Here is the list of the built-in functions currently implemented:

build-in-function:

Acos ( expression )

Arc cosine (inverse cosine) of an expression in [-1,1]. Returns a value in [0,Pi].

Asin ( expression )

Arc sine (inverse sine) of an expression in [-1,1]. Returns a value in [-Pi/2,Pi/2].

Atan ( expression )

Arc tangent (inverse tangent) of expression. Returns a value in [-Pi/2,Pi/2].

Atan2 ( expression, expression )

Arc tangent (inverse tangent) of the first expression divided by the second. Returns a value in [-Pi,Pi].

Ceil ( expression )

Rounds expression up to the nearest integer.

Cos ( expression )

Cosine of expression.

Cosh ( expression )

Hyperbolic cosine of expression.

Exp ( expression )

Returns the value of e (the base of natural logarithms) raised to the power of expression.

Fabs ( expression )

Absolute value of expression.

Fmod ( expression, expression )

Remainder of the division of the first expression by the second, with the sign of the first.

Floor ( expression )

Rounds expression down to the nearest integer.

Hypot ( expression, expression )

Returns the square root of the sum of the square of its two arguments.

Log ( expression )

Natural logarithm of expression (expression > 0).

Log10 ( expression )

Base 10 logarithm of expression (expression > 0).

Modulo ( expression, expression )

see Fmod( expression, expression ).

Rand ( expression )

Random number between zero and expression.

Sqrt ( expression )

Square root of expression (expression >= 0).

Sin ( expression )

Sine of expression.

Sinh ( expression )

Hyperbolic sine of expression.

Tan ( expression )

Tangent of expression.

Tanh ( expression )

Hyperbolic tangent of expression.

2.4 User-defined functions

User-defined functions take no arguments, and are evaluated as if a file containing the function body was included at the location of the Call statement.

Function string

Begins the declaration of a user-defined function named string. The body of the function starts on the line after `Function string', and can contain any Gmsh command.

Return

Ends the body of the current user-defined function. Function declarations cannot be imbricated.

Call string;

Executes the body of a (previously defined) function named string.

See 7.5 `t5.geo', for an example of a user-defined function.

2.5 Loops and conditionals

Loops and conditionals are defined as follows, and can be imbricated:

For ( expression : expression )

Iterates from the value of the first expression to the value of the second expression, with a unit incrementation step. At each iteration, the commands comprised between `For ( expression : expression )' and the matching EndFor are executed.

For ( expression : expression : expression )

Iterates from the value of the first expression to the value of the second expression, with a positive or negative incrementation step equal to the third expression. At each iteration, the commands comprised between `For ( expression : expression : expression )' and the matching EndFor are executed.

For string In { expression : expression }

Iterates from the value of the first expression to the value of the second expression, with a unit incrementation step. At each iteration, the value of the iterate is affected to an expression named string, and the commands comprised between `For string In { expression : expression }' and the matching EndFor are executed.

For string In { expression : expression : expression }

Iterates from the value of the first expression to the value of the second expression, with a positive or negative incrementation step equal to the third expression. At each iteration, the value of the iterate is affected to an expression named string, and the commands comprised between `For string In { expression : expression : expression }' and the matching EndFor are executed.

EndFor

Ends a matching For command.

If ( expression )

The body enclosed between `If ( expression )' and the matching Endif is evaluated if expression is non-zero.

EndIf

Ends a matching If command.

See 7.5 `t5.geo', for an example of For and If commands. Gmsh does not provide any Else (or similar) command at the time of this writing.

2.6 General commands

The following commands can be used anywhere in a Gmsh ASCII text input file:

string = expression;

Creates a new expression identifier string, or affects expression to an existing expression identifier. Eleven expression identifiers are predefined (hardcoded in Gmsh's parser):

Pi

Returns 3.1415926535897932.

GMSH_MAJOR_VERSION

Returns Gmsh's major version number.

GMSH_MINOR_VERSION

Returns Gmsh's minor version number.

GMSH_PATCH_VERSION

Returns Gmsh's patch version number.

MPI_Size

Returns the number of processors on which Gmsh is running (always 1, except if you compiled Gmsh's parallel extensions).

MPI_Rank

Returns the rank of the current processor.

newp

Returns the next available point number. As explained in 3. Geometry module, a unique number must be associated with every geometrical point: newp permits to know the highest number already attributed (plus one). This is mostly useful when writing user-defined functions (see section 2.4 User-defined functions) or general geometric primitives, when one does not know a priori which numbers are already attributed, and which ones are still available.

newl

Returns the next available line number.

news

Returns the next available surface number.

newv

Returns the next available volume number.

newll

Returns the next available line loop number.

newsl

Returns the next available surface loop number.

newreg

Returns the next available region number. That is, newreg returns the maximum of newp, newl, news, newv and all physical entity numbers(5).

string [ ] = { };

Creates a new expression list identifier string[] with an empty list.

string [ ] = { expression-list };

Creates a new expression list identifier string[] with the list expression-list, or affects expression-list to an existing expression list identifier. (Remember the remark we made when we defined expression-lists: the braces enclosing an expression-list are optional if the list only contains a single item.)

string [ { expression-list } ] = { expression-list };

Affects each item in the right hand side expression-list to the elements (indexed by the left hand side expression-list) of an existing expression list identifier. The two expression-lists must contain the same number of items.

real-option = expression;

Affects expression to a real option.

char-option = char-expression;

Affects char-expression to a character option.

color-option = color-expression;

Affects color-expression to a color option.

string | real-option += expression;

Adds and affects expression to an existing expression identifier or to a real option.

string | real-option -= expression;

Subtracts and affects expression to an existing expression identifier or to a real option.

string | real-option *= expression;

Multiplies and affects expression to an existing expression identifier or to a real option.

string | real-option /= expression;

Divides and affects expression to an existing expression identifier or to a real option.

string [ ] += { expression-list };

Appends expression-list to an existing expression list or creates a new expression list with expression-list).

string [ { expression-list } ] += { expression-list };

Adds and affects, item per item, the right hand side expression-list to an existing expression list identifier.

string [ { expression-list } ] -= { expression-list };

Subtracts and affects, item per item, the right hand side expression-list to an existing expression list identifier.

string [ { expression-list } ] *= { expression-list };

Multiplies and affects, item per item, the right hand side expression-list to an existing expression list identifier.

string [ { expression-list } ] /= { expression-list };

Divides and affects, item per item, the right hand side expression-list to an existing expression list identifier.

Exit;

Aborts the current script.

Printf ( char-expression , expression-list );

Prints a character expression in the information window and/or on the terminal. Printf is equivalent to the printf C function: char-expression is a format string that can contain formatting characters (%f, %e, etc.). Note that all expressions are evaluated as floating point values in Gmsh (see section 2.1 Expressions), so that only valid floating point formatting characters make sense in char-expression. See 7.5 `t5.geo', for an example of the use of Printf.

Printf ( char-expression , expression-list ) > char-expression;

Same as Printf above, but output the expression in a file.

Printf ( char-expression , expression-list ) >> char-expression;

Same as Printf above, but appends the expression at the end of the file.

Merge char-expression;

Merges a file named char-expression. This command is equivalent to the `File->Merge' menu in the graphical user interface. If the path in char-expression is not absolute, char-expression is appended to the path of the current file.

Draw;

Redraws the scene.

BoundingBox;

Recomputes the bounding box of the scene (which is normally computed only after new geometrical entities are added or after files are included or merged). The bounding box is computed as follows:

1. If there is a mesh (i.e., at least one mesh vertex), the bounding box is taken as the box enclosing all the mesh vertices;
2. If there is no mesh but there is a geometry (i.e., at least one geometrical point), the bounding box is taken as the box enclosing all the geometrical points;
3. If there is no mesh and no geometry, but there are some post-processing views, the bounding box is taken as the box enclosing all the primitives in the views.

BoundingBox { expression, expression, expression, expression, expression, expression };

Forces the bounding box of the scene to the given expressions (X min, X max, Y min, Y max, Z min, Z max).

Delete All;

Deletes all geometrical entities and all currently loaded meshes.

Delete Physicals;

Deletes all physical groups.

Mesh expression;

Generate expression-D mesh.

Print char-expression;

Prints the graphic window in a file named char-expression, using the current Print.Format (see section 2.7 General options). If the path in char-expression is not absolute, char-expression is appended to the path of the current file.

Sleep expression;

Suspends the execution of Gmsh during expression seconds.

System char-expression;

Executes a system call.

Include char-expression;

Includes the file named char-expression at the current position in the input file. The include command should be given on a line of its own. If the path in char-expression is not absolute, char-expression is appended to the path of the current file.

2.7 General options

Here is the list of the general char-options, real-options and color-options (in that order--check the default values to see the actual types). Most of these options are accessible in the graphical user interface, but not all of them. When running Gmsh interactively, changing an option in the ASCII text input file will modify the option in the GUI in real time. This permits for example to resize the graphical window in a script, or to interact with animations in the script and in the GUI at the same time.

Gmsh's default behavior is to save some of these options in a per-user "session resource" file (General.SessionFileName) every time Gmsh is shut down. This permits for example to automatically remember the size and location of the windows or which fonts to use. Other options can be saved in a per-user "option" file (General.OptionsFileName), automatically loaded by Gmsh every time it starts up, by using the `Tools->Options->Save as defaults' menu.

General.AxesFormatX

Number format for X-axis (in standard C form)
Default value: "%.3g"
Saved in: General.OptionsFileName

General.AxesFormatY

Number format for Y-axis (in standard C form)
Default value: "%.3g"
Saved in: General.OptionsFileName

General.AxesFormatZ

Number format for Z-axis (in standard C form)
Default value: "%.3g"
Saved in: General.OptionsFileName

General.AxesLabelX

X-axis label
Default value: ""
Saved in: General.OptionsFileName

General.AxesLabelY

Y-axis label
Default value: ""
Saved in: General.OptionsFileName

General.AxesLabelZ

Z-axis label
Default value: ""
Saved in: General.OptionsFileName

General.DefaultFileName

Default project file name
Default value: "untitled.geo"
Saved in: General.OptionsFileName

General.Display

X server to use (only for Unix versions)
Default value: ""
Saved in: -

General.ErrorFileName

File into which the log is saved if a fatal error occurs
Default value: ".gmsh-errors"
Saved in: General.OptionsFileName

General.FileName

Current project file name (read-only)
Default value: ""
Saved in: -

General.FltkTheme

FLTK user interface theme (try e.g. plastic or gtk+)
Default value: ""
Saved in: General.OptionsFileName

General.GraphicsFont

Font used in the graphic window
Default value: "Helvetica"
Saved in: General.OptionsFileName

General.OptionsFileName

Option file created with `Tools->Options->Save'; automatically read on startup
Default value: ".gmsh-options"
Saved in: General.SessionFileName

General.SessionFileName

Option file into which session specific information is saved; automatically read on startup
Default value: ".gmshrc"
Saved in: -

General.TextEditor

System command to launch a text editor
Default value: "open -t %s"
Saved in: General.OptionsFileName

General.TmpFileName

Temporary file used by the geometry module
Default value: ".gmsh-tmp"
Saved in: General.SessionFileName

General.WebBrowser

System command to launch a web browser
Default value: "open %s"
Saved in: General.OptionsFileName

General.AlphaBlending

Enable alpha blending (transparency) in post-processing views
Default value: 1
Saved in: General.OptionsFileName

General.Antialiasing

Use multisample antialiasing (will slow down rendering)
Default value: 0
Saved in: General.OptionsFileName

General.ArrowHeadRadius

Relative radius of arrow head
Default value: 0.12
Saved in: General.OptionsFileName

General.ArrowStemLength

Relative length of arrow stem
Default value: 0.56
Saved in: General.OptionsFileName

General.ArrowStemRadius

Relative radius of arrow stem
Default value: 0.02
Saved in: General.OptionsFileName

General.Axes

Axes (0=none, 1=simple axes, 2=box, 3=full grid, 4=open grid, 5=ruler)
Default value: 0
Saved in: General.OptionsFileName

General.AxesMikado

Mikado axes style
Default value: 0
Saved in: General.OptionsFileName

General.AxesAutoPosition

Position the axes automatically
Default value: 1
Saved in: General.OptionsFileName

General.AxesMaxX

Maximum X-axis coordinate
Default value: 1
Saved in: General.OptionsFileName

General.AxesMaxY

Maximum Y-axis coordinate
Default value: 1
Saved in: General.OptionsFileName

General.AxesMaxZ

Maximum Z-axis coordinate
Default value: 1
Saved in: General.OptionsFileName

General.AxesMinX

Minimum X-axis coordinate
Default value: 0
Saved in: General.OptionsFileName

General.AxesMinY

Minimum Y-axis coordinate
Default value: 0
Saved in: General.OptionsFileName

General.AxesMinZ

Minimum Z-axis coordinate
Default value: 0
Saved in: General.OptionsFileName

General.AxesTicsX

Number of tics on the X-axis
Default value: 5
Saved in: General.OptionsFileName

General.AxesTicsY

Number of tics on the Y-axis
Default value: 5
Saved in: General.OptionsFileName

General.AxesTicsZ

Number of tics on the Z-axis
Default value: 5
Saved in: General.OptionsFileName

General.BackgroundGradient

Draw background gradient (0=none, 1=vertical, 2=horizontal, 3=radial)
Default value: 1
Saved in: General.OptionsFileName

General.Clip0

Enable clipping plane 0 (Geometry=2^0, Mesh=2^1, View[i]=2^(2+i))
Default value: 0
Saved in: -

General.Clip0A

First coefficient in equation for clipping plane 0 (`A' in `AX+BY+CZ+D=0')
Default value: 1
Saved in: -

General.Clip0B

Second coefficient in equation for clipping plane 0 (`B' in `AX+BY+CZ+D=0')
Default value: 0
Saved in: -

General.Clip0C

Third coefficient in equation for clipping plane 0 (`C' in `AX+BY+CZ+D=0')
Default value: 0
Saved in: -

General.Clip0D

Fourth coefficient in equation for clipping plane 0 (`D' in `AX+BY+CZ+D=0')
Default value: 0
Saved in: -

General.Clip1

Enable clipping plane 1 (Geometry=2^0, Mesh=2^1, View[i]=2^(2+i))
Default value: 0
Saved in: -

General.Clip1A

First coefficient in equation for clipping plane 1
Default value: 1
Saved in: -

General.Clip1B

Second coefficient in equation for clipping plane 1
Default value: 0
Saved in: -

General.Clip1C

Third coefficient in equation for clipping plane 1
Default value: 0
Saved in: -

General.Clip1D

Fourth coefficient in equation for clipping plane 1
Default value: 0
Saved in: -

General.Clip2

Enable clipping plane 2 (Geometry=2^0, Mesh=2^1, View[i]=2^(2+i))
Default value: 0
Saved in: -

General.Clip2A

First coefficient in equation for clipping plane 2
Default value: 1
Saved in: -

General.Clip2B

Second coefficient in equation for clipping plane 2
Default value: 0
Saved in: -

General.Clip2C

Third coefficient in equation for clipping plane 2
Default value: 0
Saved in: -

General.Clip2D

Fourth coefficient in equation for clipping plane 2
Default value: 0
Saved in: -

General.Clip3

Enable clipping plane 3 (Geometry=2^0, Mesh=2^1, View[i]=2^(2+i))
Default value: 0
Saved in: -

General.Clip3A

First coefficient in equation for clipping plane 3
Default value: 1
Saved in: -

General.Clip3B

Second coefficient in equation for clipping plane 3
Default value: 0
Saved in: -

General.Clip3C

Third coefficient in equation for clipping plane 3
Default value: 0
Saved in: -

General.Clip3D

Fourth coefficient in equation for clipping plane 3
Default value: 0
Saved in: -

General.Clip4

Enable clipping plane 4 (Geometry=2^0, Mesh=2^1, View[i]=2^(2+i))
Default value: 0
Saved in: -

General.Clip4A

First coefficient in equation for clipping plane 4
Default value: 1
Saved in: -

General.Clip4B

Second coefficient in equation for clipping plane 4
Default value: 0
Saved in: -

General.Clip4C

Third coefficient in equation for clipping plane 4
Default value: 0
Saved in: -

General.Clip4D

Fourth coefficient in equation for clipping plane 4
Default value: 0
Saved in: -

General.Clip5

Enable clipping plane 5 (Geometry=2^0, Mesh=2^1, View[i]=2^(2+i))
Default value: 0
Saved in: -

General.Clip5A

First coefficient in equation for clipping plane 5
Default value: 1
Saved in: -

General.Clip5B

Second coefficient in equation for clipping plane 5
Default value: 0
Saved in: -

General.Clip5C

Third coefficient in equation for clipping plane 5
Default value: 0
Saved in: -

General.Clip5D

Fourth coefficient in equation for clipping plane 5
Default value: 0
Saved in: -

General.ClipFactor

Near and far clipping plane distance factor (decrease value for better z-buffer resolution)
Default value: 5
Saved in: -

General.ClipOnlyDrawIntersectingVolume

Only draw layer of elements that intersect the clipping plane
Default value: 0
Saved in: General.OptionsFileName

General.ClipOnlyVolume

Only clip volume elements
Default value: 0
Saved in: General.OptionsFileName

General.ClipPositionX

Horizontal position (in pixels) of the upper left corner of the clipping planes window
Default value: 650
Saved in: General.SessionFileName

General.ClipPositionY

Vertical position (in pixels) of the upper left corner of the clipping planes window
Default value: 150
Saved in: General.SessionFileName

General.ClipWholeElements

Clip whole elements
Default value: 0
Saved in: General.OptionsFileName

General.ColorScheme

Default color scheme (0=dark, 1=light or 2=grayscale)
Default value: 1
Saved in: General.OptionsFileName

General.ConfirmOverwrite

Ask confirmation before overwriting files?
Default value: 1
Saved in: General.OptionsFileName

General.ContextPositionX

Horizontal position (in pixels) of the upper left corner of the contextual windows
Default value: 650
Saved in: General.SessionFileName

General.ContextPositionY

Vertical position (in pixels) of the upper left corner of the contextual windows
Default value: 150
Saved in: General.SessionFileName

General.DoubleBuffer

Use a double buffered graphic window (on Unix, should be set to 0 when working on a remote host without GLX)
Default value: 1
Saved in: General.OptionsFileName

General.DrawBoundingBoxes

Draw bounding boxes
Default value: 0
Saved in: General.OptionsFileName

General.ExpertMode

Enable expert mode (to disable all the messages meant for inexperienced users)
Default value: 0
Saved in: General.OptionsFileName

General.FastRedraw

Draw simplified model while rotating, panning and zooming
Default value: 0
Saved in: General.OptionsFileName

General.FieldPositionX

Horizontal position (in pixels) of the upper left corner of the field window
Default value: 650
Saved in: General.SessionFileName

General.FieldPositionY

Vertical position (in pixels) of the upper left corner of the field window
Default value: 550
Saved in: General.SessionFileName

General.FieldHeight

Height (in pixels) of the field window
Default value: 300
Saved in: General.SessionFileName

General.FieldWidth

Width (in pixels) of the field window
Default value: 300
Saved in: General.SessionFileName

General.FileChooserPositionX

Horizontal position (in pixels) of the upper left corner of the file chooser windows
Default value: 200
Saved in: General.SessionFileName

General.FileChooserPositionY

Vertical position (in pixels) of the upper left corner of the file chooser windows
Default value: 200
Saved in: General.SessionFileName

General.FontSize

Size of the font in the user interface (-1=automatic)
Default value: -1
Saved in: General.OptionsFileName

General.GraphicsFontSize

Size of the font in the graphic window
Default value: 17
Saved in: General.OptionsFileName

General.GraphicsHeight

Height (in pixels) of the graphic window
Default value: 600
Saved in: General.SessionFileName

General.GraphicsPositionX

Horizontal position (in pixels) of the upper left corner of the graphic window
Default value: 50
Saved in: General.SessionFileName

General.GraphicsPositionY

Vertical position (in pixels) of the upper left corner of the graphic window
Default value: 50
Saved in: General.SessionFileName

General.GraphicsWidth

Width (in pixels) of the graphic window
Default value: 600
Saved in: General.SessionFileName

General.InitialModule

Module launched on startup (0=automatic, 1=geometry, 2=mesh, 3=solver, 4=post-processing)
Default value: 0
Saved in: General.OptionsFileName

General.Light0

Enable light source 0
Default value: 1
Saved in: General.OptionsFileName

General.Light0X

X position of light source 0
Default value: 0.65
Saved in: General.OptionsFileName

General.Light0Y

Y position of light source 0
Default value: 0.65
Saved in: General.OptionsFileName

General.Light0Z

Z position of light source 0
Default value: 1
Saved in: General.OptionsFileName

General.Light0W

Divisor of the X, Y and Z coordinates of light source 0 (W=0 means infinitely far source)
Default value: 0
Saved in: General.OptionsFileName

General.Light1

Enable light source 1
Default value: 0
Saved in: General.OptionsFileName

General.Light1X

X position of light source 1
Default value: 0.5
Saved in: General.OptionsFileName

General.Light1Y

Y position of light source 1
Default value: 0.3
Saved in: General.OptionsFileName

General.Light1Z

Z position of light source 1
Default value: 1
Saved in: General.OptionsFileName

General.Light1W

Divisor of the X, Y and Z coordinates of light source 1 (W=0 means infinitely far source)
Default value: 0
Saved in: General.OptionsFileName

General.Light2

Enable light source 2
Default value: 0
Saved in: General.OptionsFileName

General.Light2X

X position of light source 2
Default value: 0.5
Saved in: General.OptionsFileName

General.Light2Y

Y position of light source 2
Default value: 0.3
Saved in: General.OptionsFileName

General.Light2Z

Z position of light source 2
Default value: 1
Saved in: General.OptionsFileName

General.Light2W

Divisor of the X, Y and Z coordinates of light source 2 (W=0 means infinitely far source)
Default value: 0
Saved in: General.OptionsFileName

General.Light3

Enable light source 3
Default value: 0
Saved in: General.OptionsFileName

General.Light3X

X position of light source 3
Default value: 0.5
Saved in: General.OptionsFileName

General.Light3Y

Y position of light source 3
Default value: 0.3
Saved in: General.OptionsFileName

General.Light3Z

Z position of light source 3
Default value: 1
Saved in: General.OptionsFileName

General.Light3W

Divisor of the X, Y and Z coordinates of light source 3 (W=0 means infinitely far source)
Default value: 0
Saved in: General.OptionsFileName

General.Light4

Enable light source 4
Default value: 0
Saved in: General.OptionsFileName

General.Light4X

X position of light source 4
Default value: 0.5
Saved in: General.OptionsFileName

General.Light4Y

Y position of light source 4
Default value: 0.3
Saved in: General.OptionsFileName

General.Light4Z

Z position of light source 4
Default value: 1
Saved in: General.OptionsFileName

General.Light4W

Divisor of the X, Y and Z coordinates of light source 4 (W=0 means infinitely far source)
Default value: 0
Saved in: General.OptionsFileName

General.Light5

Enable light source 5
Default value: 0
Saved in: General.OptionsFileName

General.Light5X

X position of light source 5
Default value: 0.5
Saved in: General.OptionsFileName

General.Light5Y

Y position of light source 5
Default value: 0.3
Saved in: General.OptionsFileName

General.Light5Z

Z position of light source 5
Default value: 1
Saved in: General.OptionsFileName

General.Light5W

Divisor of the X, Y and Z coordinates of light source 5 (W=0 means infinitely far source)
Default value: 0
Saved in: General.OptionsFileName

General.LineWidth

Display width of lines (in pixels)
Default value: 1
Saved in: General.OptionsFileName

General.ManipulatorPositionX

Horizontal position (in pixels) of the upper left corner of the manipulator window
Default value: 650
Saved in: General.SessionFileName

General.ManipulatorPositionY

Vertical position (in pixels) of the upper left corner of the manipulator window
Default value: 150
Saved in: General.SessionFileName

General.MaxX

Maximum model coordinate along the X-axis (read-only)
Default value: 1
Saved in: -

General.MaxY

Maximum model coordinate along the Y-axis (read-only)
Default value: 1
Saved in: -

General.MaxZ

Maximum model coordinate along the Z-axis (read-only)
Default value: 1
Saved in: -

General.MenuPositionX

Horizontal position (in pixels) of the upper left corner of the menu window
Default value: 800
Saved in: General.SessionFileName

General.MenuPositionY

Vertical position (in pixels) of the upper left corner of the menu window
Default value: 50
Saved in: General.SessionFileName

General.MessagePositionX

Horizontal position (in pixels) of the upper left corner of the message window
Default value: 650
Saved in: General.SessionFileName

General.MessagePositionY

Vertical position (in pixels) of the upper left corner of the message window
Default value: 490
Saved in: General.SessionFileName

General.MessageHeight

Height (in pixels) of the message window
Default value: 300
Saved in: General.SessionFileName

General.MessageWidth

Width (in pixels) of the message window
Default value: 400
Saved in: General.SessionFileName

General.MinX

Minimum model coordinate along the X-axis (read-only)
Default value: 0
Saved in: -

General.MinY

Minimum model coordinate along the Y-axis (read-only)
Default value: 0
Saved in: -

General.MinZ

Minimum model coordinate along the Z-axis (read-only)
Default value: 0
Saved in: -

General.MouseHoverMeshes

Enable mouse hover on meshes
Default value: 0
Saved in: General.OptionsFileName

General.MouseSelection

Enable mouse selection
Default value: 1
Saved in: General.OptionsFileName

General.NonModalWindows

Force all control windows to be on top of the graphic window ("non-modal")
Default value: 1
Saved in: General.SessionFileName

General.NoPopup

Disable interactive dialog windows in scripts (and use default values instead)
Default value: 0
Saved in: General.OptionsFileName

General.OptionsPositionX

Horizontal position (in pixels) of the upper left corner of the option window
Default value: 650
Saved in: General.SessionFileName

General.OptionsPositionY

Vertical position (in pixels) of the upper left corner of the option window
Default value: 150
Saved in: General.SessionFileName

General.Orthographic

Orthographic projection mode (0=perspective projection)
Default value: 1
Saved in: General.OptionsFileName

General.PluginPositionX

Horizontal position (in pixels) of the upper left corner of the plugin window
Default value: 650
Saved in: General.SessionFileName

General.PluginPositionY

Vertical position (in pixels) of the upper left corner of the plugin window
Default value: 550
Saved in: General.SessionFileName

General.PluginHeight

Height (in pixels) of the plugin window
Default value: 300
Saved in: General.SessionFileName

General.PluginWidth

Width (in pixels) of the plugin window
Default value: 300
Saved in: General.SessionFileName

General.PointSize

Display size of points (in pixels)
Default value: 3
Saved in: General.OptionsFileName

General.PolygonOffsetAlwaysOn

Always apply polygon offset, instead of trying to detect when it is required
Default value: 0
Saved in: General.OptionsFileName

General.PolygonOffsetFactor

Polygon offset factor (offset = factor * DZ + r * units)
Default value: 0.5
Saved in: General.OptionsFileName

General.PolygonOffsetUnits

Polygon offset units (offset = factor * DZ + r * units)
Default value: 1
Saved in: General.OptionsFileName

General.QuadricSubdivisions

Number of subdivisions used to draw points or lines as spheres or cylinders
Default value: 8
Saved in: General.OptionsFileName

General.RotationX

First Euler angle (used if Trackball=0)
Default value: 0
Saved in: -

General.RotationY

Second Euler angle (used if Trackball=0)
Default value: 0
Saved in: -

General.RotationZ

Third Euler angle (used if Trackball=0)
Default value: 0
Saved in: -

General.RotationCenterGravity

Rotate around the (pseudo) center of mass instead of (RotationCenterX, RotationCenterY, RotationCenterZ)
Default value: 1
Saved in: General.OptionsFileName

General.RotationCenterX

X coordinate of the center of rotation
Default value: 0
Saved in: -

General.RotationCenterY

Y coordinate of the center of rotation
Default value: 0
Saved in: -

General.RotationCenterZ

Z coordinate of the center of rotation
Default value: 0
Saved in: -

General.SaveOptions

Automatically save current options in General.OptionsFileName each time you quit Gmsh?
Default value: 0
Saved in: General.SessionFileName

General.SaveSession

Automatically save session specific information in General.SessionFileName each time you quit Gmsh?
Default value: 1
Saved in: General.SessionFileName

General.ScaleX

X-axis scale factor
Default value: 1
Saved in: -

General.ScaleY

Y-axis scale factor
Default value: 1
Saved in: -

General.ScaleZ

Z-axis scale factor
Default value: 1
Saved in: -

General.Shininess

Material shininess
Default value: 0.4
Saved in: General.OptionsFileName

General.ShininessExponent

Material shininess exponent (between 0 and 128)
Default value: 40
Saved in: General.OptionsFileName

General.SmallAxes

Display the small axes
Default value: 1
Saved in: General.OptionsFileName

General.SmallAxesPositionX

X position of small axes (use negative values for right alignment)
Default value: -60
Saved in: General.OptionsFileName

General.SmallAxesPositionY

Y position of small axes (use negative values for bottom alignment)
Default value: -40
Saved in: General.OptionsFileName

General.SmallAxesSize

Size (in pixels) of small axes
Default value: 30
Saved in: General.OptionsFileName

General.SolverPositionX

Horizontal position (in pixels) of the upper left corner of the solver windows
Default value: 650
Saved in: General.SessionFileName

General.SolverPositionY

Vertical position (in pixels) of the upper left corner of the solver windows
Default value: 150
Saved in: General.SessionFileName

General.StatisticsPositionX

Horizontal position (in pixels) of the upper left corner of the statistic window
Default value: 650
Saved in: General.SessionFileName

General.StatisticsPositionY

Vertical position (in pixels) of the upper left corner of the statistic window
Default value: 150
Saved in: General.SessionFileName

General.SystemMenuBar

Use the system menu bar on Mac OS X?
Default value: 1
Saved in: General.SessionFileName

General.Terminal

Should information be printed on the terminal (if available)?
Default value: 0
Saved in: General.OptionsFileName

General.Tooltips

Show tooltips in the user interface
Default value: 1
Saved in: General.OptionsFileName

General.Trackball

Use trackball rotation mode
Default value: 1
Saved in: General.OptionsFileName

General.TrackballQuaternion0

First trackball quaternion component (used if General.Trackball=1)
Default value: 0
Saved in: -

General.TrackballQuaternion1

Second trackball quaternion component (used if General.Trackball=1)
Default value: 0
Saved in: -

General.TrackballQuaternion2

Third trackball quaternion component (used if General.Trackball=1)
Default value: 0
Saved in: -

General.TrackballQuaternion3

Fourth trackball quaternion component (used if General.Trackball=1)
Default value: 1
Saved in: -

General.TranslationX

X-axis translation (in model units)
Default value: 0
Saved in: -

General.TranslationY

Y-axis translation (in model units)
Default value: 0
Saved in: -

General.TranslationZ

Z-axis translation (in model units)
Default value: 0
Saved in: -

General.VectorType

Default vector display type (for normals, etc.)
Default value: 4
Saved in: General.OptionsFileName

General.Verbosity

Level of information printed during processing (0=no information)
Default value: 3
Saved in: General.OptionsFileName

General.VisibilityPositionX

Horizontal position (in pixels) of the upper left corner of the visibility window
Default value: 650
Saved in: General.SessionFileName

General.VisibilityPositionY

Vertical position (in pixels) of the upper left corner of the visibility window
Default value: 150
Saved in: General.SessionFileName

General.ZoomFactor

Middle mouse button zoom acceleration factor
Default value: 4
Saved in: General.OptionsFileName

General.Color.Background

Background color
Default value: {255,255,255}
Saved in: General.OptionsFileName

General.Color.BackgroundGradient

Background gradient color
Default value: {128,147,255}
Saved in: General.OptionsFileName

General.Color.Foreground

Foreground color
Default value: {85,85,85}
Saved in: General.OptionsFileName

General.Color.Text

Text color
Default value: {0,0,0}
Saved in: General.OptionsFileName

General.Color.Axes

Axes color
Default value: {0,0,0}
Saved in: General.OptionsFileName

General.Color.SmallAxes

Small axes color
Default value: {0,0,0}
Saved in: General.OptionsFileName

General.Color.AmbientLight

Ambient light color
Default value: {25,25,25}
Saved in: General.OptionsFileName

General.Color.DiffuseLight

Diffuse light color
Default value: {255,255,255}
Saved in: General.OptionsFileName

General.Color.SpecularLight

Specular light color
Default value: {255,255,255}
Saved in: General.OptionsFileName

Print.EpsBackground

Save image background in PostScript/PDF output
Default value: 1
Saved in: General.OptionsFileName

Print.EpsBestRoot

Try to minimize primitive splitting in BSP tree sorted PostScript/PDF output
Default value: 1
Saved in: General.OptionsFileName

Print.EpsCompress

Compress PostScript/PDF output using zlib
Default value: 0
Saved in: General.OptionsFileName

Print.EpsLineWidthFactor

Width factor for lines in PostScript/PDF output
Default value: 0.5
Saved in: General.OptionsFileName

Print.EpsOcclusionCulling

Cull occluded primitives (to reduce PostScript/PDF file size)
Default value: 1
Saved in: General.OptionsFileName

Print.EpsPointSizeFactor

Size factor for points in PostScript/PDF output
Default value: 1
Saved in: General.OptionsFileName

Print.EpsPS3Shading

Enable PostScript Level 3 shading
Default value: 0
Saved in: General.OptionsFileName

Print.EpsQuality

PostScript/PDF quality (0=bitmap, 1=vector (simple sort), 2=vector (accurate sort), 3=vector (unsorted)
Default value: 1
Saved in: General.OptionsFileName

Print.Format

File format (10=automatic)
Default value: 10
Saved in: General.OptionsFileName

Print.GeoLabels

Save labels in unrolled Gmsh geometries
Default value: 1
Saved in: General.OptionsFileName

Print.GifDither

Apply dithering to GIF output
Default value: 0
Saved in: General.OptionsFileName

Print.GifInterlace

Interlace GIF output
Default value: 0
Saved in: General.OptionsFileName

Print.GifSort

Sort the colormap in GIF output
Default value: 1
Saved in: General.OptionsFileName

Print.GifTransparent

Output transparent GIF image
Default value: 0
Saved in: General.OptionsFileName

Print.JpegQuality

JPEG quality (between 1 and 100)
Default value: 100
Saved in: General.OptionsFileName

Print.JpegSmoothing

JPEG smoothing (between 0 and 100)
Default value: 0
Saved in: General.OptionsFileName

Print.PostElementary

Save elementary region tags in mesh statistics exported as post-processing views
Default value: 1
Saved in: General.OptionsFileName

Print.PostElement

Save element numbers in mesh statistics exported as post-processing views
Default value: 0
Saved in: General.OptionsFileName

Print.PostGamma

Save Gamma quality measure in mesh statistics exported as post-processing views
Default value: 0
Saved in: General.OptionsFileName

Print.PostEta

Save Eta quality measure in mesh statistics exported as post-processing views
Default value: 0
Saved in: General.OptionsFileName

Print.PostRho

Save Rho quality measure in mesh statistics exported as post-processing views
Default value: 0
Saved in: General.OptionsFileName

Print.TexAsEquation

Print all TeX strings as equations
Default value: 0
Saved in: General.OptionsFileName

Print.Text

Print text strings?
Default value: 1
Saved in: General.OptionsFileName