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Downloads The most up-to-date installers for Window, Mac OSX and Linux can be found found at: Installers Updates Occasionally, updates will be issues without supplying new installers. This greatly reduces the size of the downloaded needed. The update packages will contain library files that simply need to be copied over the files that already exist on your system (whever you have installed ShapeX). Shapemol Shapemol is a complementary code for SHAPE that computes synthetic line profiles and maps for the molecular line emission of a numerical nebula model. shapemol solves the statistical equilibrium population of a given molecular species using the LVG approximation formalism (see Santander-García, M., Bujarrabal, V., Koning, N., & Steffen, W. 2015, A&A, 573, A56). For Shapemol to function, you need to download the data tables corresponding to the molecular species you wish to reproduce. The latest version of the Shapemol tables, along with the installation instructions, can be downloaded below. See Masa, E, Alcolea, J., Santander-García, M., Bujarrabal, V., Sánchez Contreras, C., Castro-Carrizo, A., Steffen, W., & Koning, N., 2026, A&A, in press. for details. Shapemol Tables M1-92 Example Notes: Since the last release, Shape has been revamped almost completely. In particular, the user interface (UI) and the rendering algorithms have seen profound changes. New modules and modifiers help with the workflow New manual & website help the user to get started User forum - ask questions, share tips & tricks, propose features Installers for Windows, MacOSX, Linux RPM & Debian IMPORTANT NOTE: Remember that to take full advantage of your computers RAM, you need to manually set it in the ShapeX.cfg file. Search for this file within the installation directory. Open it with Administrator privileges and add the minimum and maximum RAM that you will allow Shape to use, say e.g. 14 GB of your actual RAM of 16 GB. Edit the .cfg file in a text editor with the following lines: [JVMOptions] -Xms1000m -Xmx14000m Make sure that there are no spaces before or behind the lines with the numbers. Save the file and run Shape. At the bottom of the UI the "Total (Mb): " should now indicate approximately 1.4E4 .

Quick links Modules: Overview Downloads Modifiers: Boost Bump Density Displacement GeoRotation Image Displacement Image Texture PA/Inc Rotation Pressure Projection Random Rotation Shear Shell Size Spiral Squeeze Squish Stretch Taper Temperature Texture Displacem. Translation Twist Universal Velocity Warp Key sub-systems: Overview

Shape The interactive 3-D astrophysical laboratory Images inspire us. Images lead to ideas. Shape was made as a tool to test astrophysical inspiration. Play True or False. By finding out whether an idea works or not, either way, we deliver new insight into nature for ourselves and others. That is why with Shape we make 3-D images of the universe...and more... Shape responds to your scientific creativity for morpho-kinematic modeling or spectral radiation transfer calculations. Create schematic educational visualizations or even photo-realistic images of astronomical objects. Our Introduction and Overview gives you more information about what you can do with Shape. UPDATE REQUIRED (January 21, 2022) Due to a bug in some renders after camera rotation, an update is needed. Please go to the DOWNLOADS for a link to the patch and instructions. SBa Galaxy This 3-D volumetric galaxy model was created in ShapeX based on a detailed analysis of an actual galaxy image. The Orion Nebula This volumetric 3-D model of the Orion Nebula was created using pure polygon mesh and path objects with radiation transfer computation for the scattering and absorption by the dust from the central illuminating stars. Proto-planetary disk with jet. The dusty disk of this proto-planetary object has an enriched structure using noise-textures added to a relatively low-resolution hydrodynamic simulation from the Hydro Module. The disk and jet were then separated using filters and assigned different emission (jet) and dust scattering (disk) properties. Ring Nebula For the creation of this planetary nebula the application of image texture mapping along the line of sight allowed to include details of the dusty globules at precisely the right projected positions in the nebula. The environment of Eta Carinae This is the complex mesh structure that Mehner et al. (2016) used to model the fast expanding gaseous environment of the massive Eta Carinae stellar binary system. Eta Carinae Homunculus model This simple bipolar model of the dusty Homunculus around Eta Carinae demonstrates the multi-wavelength modeling capabilities with ShapeX. From left to right the wavelength range of the rendering moves from the optical to the infrared. About Shape was created by Wolfgang Steffen and Nico Koning. Shape is free software supported by the Institute of Astronomy, UNAM. Legal and Privacy Information Home: Homepage_about User Guide Index Introduction Learn about the possibilities and limitations of astrophysical modeling and visualization in Shape. What types of physical models can be done. Whether you pursue research or outreach, find out what you can do and what you need to learn to successfully apply Shape in your field. Overview A quick tour is given through the integrated modules of Shape is given. We briefly describe how they work individually and how the general workflow brings everything together via interactive input but no need for a single line of coding from the user. Modules The modular design of Shape allows the user to concentrate on the job at hand. The desktop and the main toolbar are the hubs to get you around. In this section we describe the functionality of each of the modules, so you can quickly decide which one will be needed for your project. Goto Introduction Goto Overview Goto Modules Data Preparation Images, spatially resolved spectra and other data can be displayed as direct background references to build your models. Such data images need to be prepared carefully and correctly imported into Shape. In this section we describe how such data images can be prepared and set up in Shape. Goto Data Preparation Coordinate Systems Detailed knowledge of the various coordinate systems is necessary to correctly modeling in Shape. This is particularly true when kinematic are to be modeled. Here is a description of the coordinate systems in different contexts of the available tools. Goto Coordinate Systems Radiation Transfer Mathematical and physical details about the radiation transfer on the Cartesian grid in Shape are described. The physics and approximations for the calculations of scattering on dust particles are also layed out. Radiation Transfer Home: Service Home: Contact

Filamentary texture generator in Shape LEGAL AND PRIVACY INFORMATION Impressum Dr. Wolfgang Steffen Contact: e-mail: contact@ilumbra.com Responsible for the content: Dr. Wolfgang Steffen Hautzenbergstrasse 1 67661 Kaiserslautern Germany Copyright 2021 Owners: Dr. Nico Koning (ilumbra), Dr. Wolfgang Steffen (ilumbra) Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal use the Software without restriction, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. THE SOFTWARE MAY BE USED AND DISTRIBUTED IN COMPILED FORM. NO PORTION OF THE ORIGINAL CODE MAY BE USED, CHANGED OR DISTRIBUTED WITHOUT EXPRESS PERMISSION IN WRITING BY THE COPYRIGHT OWNERS. Disclaimer of liability: Liability for the Shape software and the manual contents The Shape software is provided as is and no guarantee is given for its fitness for a particular purpose. We can not be made responsible for any incorrect scientific results or other that may or may not appear in publications of any kind. The contents of the Shape manual may not correspond to the version of the Shape software that user is applying and may therefore or for other reasons deviate from the actual functionality of the software. 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The Size Modifier scales the mesh. Different scaling factors can be applied along the x, y and z axes. The Size operator only changes the vertex position and does not affect the local coordinate system, i.e. the reference point for other modifiers, such as the velocity field, are not changed. Name: Provide a name for the modifier that closely describes its function. Lock: When enabled, this flag keeps all the scaling factors the same. The last change in any axis is adopted for all axes. x,y,z: The scaling factor by axis. Anchor: The anchor is the xyz position in space around which the scaling will be applied. This may shift the whole object towards or away from this position, depending on whether the value is smaller or larger than one. A change in anchor position does not affect the local coordinate system, it only moves the vertices of the mesh. Modifiers: Size

Modifiers The Boost Modifier is basically an enhanced version of a Boolean object or modifier. The idea is to use one mesh to regionally change the properties of another. However, instead of completely cutting out or adding to a mesh, it scales the properties by some factor that may vary spatially either through a function of space or a texture. In the example below a sphere contains a complex mesh structure which has a Boost Modifier that is linked to the spherical mesh. In the first rendering below, the boosting factor was set to zero, such the sphere is hollow in the region of the boosting mesh. In the second examples, the boosting factor for the density was set to 2, enhancing the density by that factor. The Boost Modifier is applied to the mesh to is meant to change another, in this case the inner mesh. Note that more than one boosting mesh can be applied to the main mesh. Parameters: Name: If multiple Boost Modifiers are used, make sure to name them adequately for ease of identification. Enabled: When deselected, the modifier will not be applied. Boost: This is the boosting factor that is applied to the main mesh. It can be a mathematical expression and function of the main variables such as n (density), T (temperature) or P (pressure). Note that these are the properties of the boosting mesh object, i.e. they relate to the modifiers within the boosting object itself. To make the hollow structure above, this factor was set to zero (0) and 2 for the enhancement of the structure. If set to "n" as shown, the factor is taken from the Density modifier in the boosting object. This may be a function of position, including the texture. This allows for a complex manipulation of the region covered by the boosting object. Variable: From this drop-down list select the variable upon which the boosting shall act on in the main object. Note that this is different from the variables in the Boost factor. Operation: Select the operation that the Boost Modifier shall perform on the main object. You can select from Scale, Add and Replace. Applied Object: From the drop-down list select the objects on which the Boost modifier shall act on. Several objects may be chosen. Hide itself: Generally the boosting object is used only to act upon other meshes, but is not rendered itself. This may, however, not always be the case. So, if the boosting object is a rendered object in itself, disable this flag, such that the boosting mesh itself is rendered, too. Modifiers: Boost

Key Sub-S ystem: Graphs In Shape graphs are used to display functions. The functions are either analytical or set interactively by adding control points to a curve. The control points of an interactive curve can also be loaded from an external ascii file. In modifiers the graphs are usually applied to set and display spatial variation of a quantity that is passed on to some quantity as a multiplier. In the modifiers the graphs may be single coordinate functions or they may depend on all three space coordinates in different types of coordinate systems (spherical by default, Cartesian or cylindrical). Generally the result is a single number, but in the case of the velocity field, for instance, the output can be a vector. In the Physics Module graphs commonly are a function of wavelength. The functionality and appearance of the graphs varies slightly depending on the particular context. The image of the graph on the right is taken from the Squeeze Modifier, which controls the shape of a cylindrically symmetric mesh. The function display at the top shows a line of how the function f(x) changes with the independent variable (always x). In this modifier it is the position along the axis of the object. At the bottom is a list of tabs to set a variety of f unction properties . Workflow: Analytic: By default the function is set to Point , but can be changed to Analytic with the Function drop-down list. In the analytic mode, the graph is controlled by a mathematical expression, that by default is the constant function f(x) = 1. Templates: From the Templates drop-down list a few commonly used functions can be selected that are the inserted as mathematical expressions in the editor line for the function. These templates can then be edited as needed. In our example we have typed the function manually. In additional to several standard mathematical operators such as "exp" and "abs", it includes the variables "a" and "b". Variables can have alphanumerical names. Reserved variables include "n", "t" and "Pi", referring to density, temperature and the number p. Variables: The numerical value of the variables is displayed in the Variables tab . Here the value can either be written manually or be assigned from the Math Module. If the variable was defined in the Math Module, then the flag labeled "Use global variables" needs to be set. If the flag is not set, the local manually set value is used (Local variable ). Global variables are then marked by a grey background. Global variables are accessible from any function throughout Shape. Constraints: Frequently used functions such as the Gaussian vary over an infinite range. In many practical situations the function is required to smoothly reach zero or some other fixed value within a finite range. This can be achieved by setting constraints in the Constraints tab. Here the function can be made to smoothly Fade in and Fade out within the ranges set there. The value form and to which the function converges is the "Default" which can be changed by the user. In the graph the region that is covert by the Fade in is shaded in blue and the Fade out in red. Point Graph: A point graph is set up using manually placed points. These point may also be loaded from a file (Load Ascii button). To obtain a continuous function the values between the points are interpolated. There are two modes for interpolation . By default the interpolation is linear between the points. The second is a spline interpolation that is controlled manually with separate handle on each side of the points. The spline interpolation is activated by clicking on the following icon: A green color in these icons at the top of the graph indicates that they are activated. To move the points in the graph use the left-click and drag mouse functionality. To move the spline handles , use Crtl- left-click and drag . Additional interactive functions to manipulate the points individually or collectively are available by activating some of the icons on the toolbar above the graph. If you hover over a button or icon, a tool tip shows a short description of the functionality, which are very self-explanatory in this case. The hand tool is active by default and allows one to move points by left-clicking on and dragging them. The magnifying glass: zoom in and out in the graph The next icon allows you to pan left-right and up-down in the graph. The box with a pencil is for selecting multiple points by dragging a rectangle around them, while the cursor symbols with the arrows activates moving the selected points together. Selected point are deleted by clicking on the cross icon . Note that unselected individual points can be added and removed from the right-click menu (see below). The range of the graph is adjust ed to the points in them by clicking on the icon with the two curvy arrows . As mentioned above the next icon activates the spline interpolation with two handles on each point. The wrench icon opens a pop-up windows that gives access to detailed options for the appearance of the graph . These should be largely self-explanatory. Right-click menu: The right-click menu give quick access to additional functionality for graphs. In particular there are four functions for point graphs at the top of the list. Add Point add a point to the curve where the curser is currently located. Remove Point removes a point over which the cursor is hovering. Set Point opens a small pop-up window where the exact x and y values of a point can be set. Mirror Point is a very useful function when a perfectly symmetric setting is required. When clicked while you hover over a point with coordinates (x,y) a copy of the point is added to the graph at (-x,y). The second set of functions toggle on and off various functions, which are self-explanatory. The Save Ascii function will open a dialog that allows you to save the point values of the graph in a file in ascii format. The Save Image function saves an image of the graph. In the file dialog that opens, the filename has to be give a suitable file extension for the image to be correctly saved. The extension can be one of typical file formats, such as .png or .jpg, etc. Finally, the Properties functions opens a dialog where the graph´s appearance may be customized in more detail by changing colors, tick-mark spacing, coordinate grids, etc. Special variants of graphs: Some contexts in Shape have specific features in addition to the basic functionality described above. These are explained in their specific contexts, such as the graph for the velocity modifier, which has a number of special functions. There is one common feature of the extended graphs that depend on more than one variable, which we describe here. Most function graphs have as output a single number that controls a modifier or displays some property. An exception is the velocity modifier, which has a vector as output. The basic graph that has been described above depends on a single variable. Many modifiers do, however, depend on more than one spatial dimension. Those have a separate graph that describes the spatial dependence of the output on each spatial coordinate. They are accessible through tabs at the top of the graph. The active coordinate is marked in grey. Using the default Custom Mode one can select from three different types of coordinate system in the Coordinates drop-down list: Spherical (default), Cartesian and Cylindrical. The labels of the access tabs for the graphs change their labels accordingly. Note that for the spherical coordinates the label convention is that of the North America, with q being longitude and f the latitude. SEPARABILITY: an important property of the default behavior of these graph is that the resulting function F(u,v,w) is separable in their component functions: F(u,v,w) = f0 * f(u) * f(v) * f(w) where f0 is a constant parameter set by the user under the Coordinates drop-down list. Non-separable functions: a non-separable analytic function can be set up when enabling the Analytic mode from the the Mode drop-down list. This feature requires an analytic description of the function and a point-graph can not be used. As before, one chooses the type of coordinate system from the Coordinates drop-down list. Then in the function editor a formula is types as a function of the general coordinates (u,v,w) as shown in the example on the right. The coordinates have to be in terms of the letters u,v and w, no matter which type of coordinates is chosen. Their meaning changes automatically to (x,y,z), (r, q,f) or (r, q, z ) for Cartesian, spherical or cylindrical coordinates, respectively. The image on the right shows a rendering of the density that was described by the analytic function above it. It illustrates the how the wavelength of the sinusoidal pattern can be continuously changed by mixing the coordinates appropriately.

The Warp Modifier rotates the mesh vertices as a function of distance around an axis. To actually be a warped surface, the axis of the Widget for the Warp Modifier needs to be at an angle to a reference plane such as a flat disk. Name: Set a name that allows you to identify this modifier easily. Enabled: When this flag is turned off, the Warp Modifier is switched off. Deg: If set, the the rotation as a function of distance in the Magnitude Graph is given in degrees per unit distance. When switched off, then it will be radians per unit distance. Magnitude: Opens the function graph to set how the rotation angle is as a function of distance from the local coordinate system set by the Widget. Widget: The Widget opens the Widget Dialog. It allows you to change the direction of the Warp Modifier. The turquoise arrow indicates the direction around which the rotation will be performed. In the example it was rotated around the original x-axis by 30 degrees. Modifiers: Warp

Math module of the Shape software. Math Module Overview The Math module is a tool to centralize parameter values that are used in more than one place in Shape. In a way similar to a spreadsheet it allows to compute variables from other variables that have already been defined further up. This makes it possible to set up a complex mathematical model of physical processes that can then be harnessed throughout the rest of Shape. Global Variables: Since the variables defined in the Math Module can be used throughout Shape, they are called Global Variables. Whenever you wish to use variables from the Math Module in other modules, make sure to enable the flag "Use global variables" where applicable. Workflow The basic workflow consists first in adding new slots for new variables in the order of dependency, if any. Then provide a meaningful name for and defining their relationships and values. They can then be used in a variety of contexts throughout Shape. Variable Names: While Shape automatically assigns a letter as a name for new variables, it is very highly recommended to change them with meaningful and descriptive names, such that they can easily be understood wherever they might appear in Shape. The name can be changed by double-clicking on the name field of the variable. Column Functionalities Variable: This column contains the name of the global variables. In order to use a variable in some other module of Shape, the name needs to match. Upper and lower case letters are not distinguished. When a new variable is added, it receives a default name in alphabetical order. Change the variable names to something descriptive of the meaning of its content. Expression: Variables get assign a value through a mathematical expression in this column. In most cases this will simply be a value. A value can be given in integer or floating point format as well as scientific format such as 1.09435e-7 for numbers that are much smaller than 1, or 3.2E15 those that are much larger than 1. In addition to numbers the field can contain more complex mathematical expression, including those combining one or more global variables that are further up in list. To avoid recursive dependencies, variables further down can not be included. Valid mathematical expression may include the basic symbolic operators +-*/ and ^, but also common textual operators which include the following reserved functions and variable names: POWER, SIN, COS, TAN, COT, RAND, CSC, ARCSIN, ARCCOS, ARCTAN, EXP, LN, LOG10, LOG2, ABS, SQRT, ROUND, ARCTANH, UNARYMINUS, LT, GT, and the irrational numbers "e" and "pi"; As mentioned above, these functions can also be written with lower-case letters. Menu bar The buttons on the top menu bar of the Math Module control the overall content of the Math Module. Calculate : The Calculate button executes all calculations that may in standby, e.g. for iterative computations. Direct calculations of variables that depend on variables further up are executed on confirming the variable name with the Enter key. Variable : The Variable button adds a new variable to the end of the list. The variables sequentially get names of single letters in alphabetical order. As mentioned above, it is recommended to change these names to something descriptive of its meaning. The variable name is changed by double-clicking on the text field. Separator : Separators are used to keep different sections of the list of variables clearly distinct. They can also function as headings if you add some descriptive text to their text fields. The separators are colored in dark blue. Constants : This button adds a set of variables that contain the most important natural constants in SI units. If you only need a subset of them, simply select the unwanted ones and delete them with the Remove button. Remove : To remove variables from the Math Module, select them and click the Remove button. You can select several variable together with Shift-Click and remove them in one operation. A confirmation dialog helps to make sure that you do not delete variables by accident.. Up & Down : To move a variable in position in the list, select the variable and click on the Up or Down button to move it by one position. Repeat the operation until the variable is in the desired position. Defaults : Use these buttons to restore the default values that variables may have in the Default field. Note that this button restores the defaults of ALL variables at once . Individual or a subset of defaults have to be reset manually. Save & Load : In order to keep sets of variable interchangeable between different projects that have similar setups, one can save the content of the Math Module in a file with the Save button. To open a saved set of variables use the Load button.

Filamentary texture generator in Shape Key Sub-S ystem: Textures Many astronomical objects, especially nebulas have filaments with random structures. This can be simulated with procedural 3-D texture s. In Shape procedural textures can be applied to physical quantities such as density, temperature, velocity, etc . These textures are multiplied on top of the spatial variation given by the Magnitude of a quantity. Open the Texture Parameter Panel by clicking on the Edit button beside the Texture label in the parameter panel of a selected modifier. Getting the right texture may require quite a bit of experimentation, often combining several basic textures. Texture Parameter Panel The Texture Parameter Panel has several sections. At the top-left is the preview window, where a single slice from the x-y coordinate plane of the 3-D texture is shown. A list of combined basic textures is below the preview window and various types of parameters are at the top-right. Transformation modifiers can be added at the bottom-right. Basic Workflow Initially the texture editor is blank. A new texture is added from a list of different types after clicking on the Add button to the right of the Textures List. The most commonly used type is the Space Convolution noise. Now a preview of the texture is generated using the default parameters. To get the texture that is needed change the parameters until a suitable result is obtained. More than one texture may be combined by adding further textures to the list. Note that the combination is done in the form of a multiplication of the texture values in the range (0-1). Therefore, the more textures you combine, locally the result becomes smaller and smaller. In the modifiers area, rotation and translation modifiers can be applied that are similar to the corresponding image modifiers applied in the Render Module. This is not descussed in more detail in this section. Textures Panel Add: Opens a dialog with a list of different types of procedural noise from which to choose. When you click on OK, the new texture is included in the list of already chosen textures. Del: Deletes the selected texture from the list. Up & Down : Move the selected texture up or down in the list. Copy & Paste: Copy stores the selected texture in a buffer. Paste pastes the copied texture as a new texture to the list. Note: As mentioned above, if there is more than one texture they are combined as a local product of their values, which range in the interval (1,0). Moving the textures up and down in the list does not change the result since multiplication is a commutative operation. However, if you explicitly name the textures, the sequence may help at keeping order General: Name: Set a name for this texture Enable: Enable or disable this texture Seamless : This parameter works together with the Distortion (see below). If a Distortion is applied that stretches the texture along the angle in a cylindrical coordinate system, a discontinuity appears at the 0 to 360 degrees transition. To prevent this enable the Seamless flag. An attempt is then made to generate a seamless texture by copying and rotating the same texture by 180 degrees and overlapping the two with a linear transition between the two that excludes the seam region. Currently, the result is a seamless texture that has a 180 degrees point symmetry. Bias: Sets a minimum intensity for the texture. If b is the bias level, now the range for the texture is (b,1). Properties: The detailed parameters for different types of textures vary. Here we discuss the example of Sparse Convolution Noise, which is the most suitable for most filamentary features in diverse nebular objects. Many of the parameters are common to all textures, others will differ. But a bit of experimentation will clarify the meaning of the differing parameters. Sparse Convolution Noise: Scale: The scale of the texture can be set separately in the three coordinate directions. By default they are looked together, i.e. when you change one of them, the other two automatically get the same value. They can be unlocked by unchecking the Lock flag. Then the values can be set independently. To asses the size of the features in the context of the model domain note that the preview window has the same size as the scene size in the Render Module. X Y Z Offset: These parameters move the texture along the corresponding axis. The units are those of the Render Module. Exponent : Controls the contrast between the highest and lowest levels of brightness. High values deemphasize initially lower values. Freq: The levels of spatial frequencies to be included in the random noise generation. Higher values will include smaller features. Type 2: This type generates a different look and overall smaller structures. Invert: inverts the greyscale, the interval (0,1) is linearly mapped to (1,0). Image Size: Sets the pixel size of the texture preview image. Z slice : Selects the slice to be shown in the preview. Changing the value moves the preview through the cube of slices along the line of sight. Distortion: This button opens a dialog that controls the re-mapping of the noise as a function of position. Analytical expressions can be set up to remap the noise in different coordinate systems. This allows the user to stretch the noise pattern in radial or circular directions. There is an example for such a distorted texture on the right. The second image is the same texture after applying the Seamless flag (see above). Below is the dialog that opens when you click on the Distortion button. It is similar to other Graphs . Make sure to set the correct coordinate system for the distortion to be applied. The example uses the Cylindrical Coordinate system and distorts the radial and the angular directions. Some experimentation with the analytic expression or point graph is likely needed to get the desired result.

Modules In this section we give an overview of the functionality of the different modules and provide links to more detailed information on how to use them and their subsystems. Click on the Module Icon to the left of the description for more information and access to video tutorials on the module. 3-D Module In the 3-D Module the geometric and most other properties of a model are set up interactively. Description Render Module This module takes care of the rendering of image and position-velocity diagrams and a number of settings for other render options. Description Physics Module Radiation transport properties such as emissivity, absorption or scattering are set up as materials (species) in the Physics Module. Description Desktop Module The Desktop Module is your hub to all the other modules, project files, ShapeX configuration and more. Description Video Tutorial Math Module The Math Module allows you to set up variables and relations between them that can then be used throughout Shape as "global variables". Description Modifier Module The Modifier Module lists all modifier that are currently in use and allows you to change parameters of a selection of modifiers simultaneously. Description Maps Module The Maps Module displays channels maps of the 3-D model. The number and velocity range between the first and last channel can be set up. Description Animation Module Most parameters in Shape can be animated over time. This can be used to generate time variation of the models either for scientific modeling of time varying phenomena or for visualization purposes. Description Filter Module Filters for various physical quantities can be defined here. They can then be applied to objects in the 3-D Module. Description Movie Module In the Movie Module one or more animation sequences can be concatenated to a movie and exported for viewing with an external movie player. Description Export Module The Export Module exports the 3-D model into various output formats that can then be used as data for external use. Description Hydrodynamics Module Shape is the first astrophysical tool to introduce an interactive mesh-based setup for such simulations without the need of programming or scripting by the user. Description

Key Sub-S ystem: Coordinate Systems There are several coordinate systems defined in Shape. First of all in most contexts the coordinates may be defined in Cartesian, Spherical or Cylindrical coordinates. Note that for the spherical coordinates the label convention is that of the North America, with q being longitude and f the latitude. Hierarchy of coordinate systems: In addition to the types of coordinate system, there is a hierarchy that determines the origin and orientation of the coordinates. First there is the global "world" coordinate system that is fixed and everything else is embedded in this system. The orientation of the world coordinate system is show by the colored coordinate axes in the lower left corner of the 3D views in the 3D Module (see images on the right). Note that it is not centered on the center of the coordinate system and only provides a visual cue of the orientation. The colors of the xyz axes follow the common order of the color channels rgb (red, green, blue), respectively. Every object has its own "local" coordinate system , that may move around in the world coordinate system depending on the types of modifier that are applied. As an illustration compare the two images on the right. In the first one the spherical mesh and the density distribution are centered on the world coordinate system. No changes have been made to any positions. In the second example a Translation Modifier has been applied. It moves the mesh away from the World Origin. Not only the mesh is moved but the density distribution goes along. Similarly, the Rotation Modifier will rotate the density structures along with the mesh, since thee local coordinate system changes . The translation, rotation and scale operations can be interactively handled using the corresponding Move, Rotate and Size tools in the System tab that is located to the left of teh 3-D views. It is important to note that, contrary to the Translation and Rotation modifiers, the Size tool and Modifier does NOT change the scaling of the local coordinate system. This would cause too many practical problem during modeling. It only changes the mesh. This is similar to the Displacement modifier which only moves the mesh, not the coordinate system. For rotating only the mesh, operators such as the Twist modifier can be applied. In third place there is the "widget" coordinate system that is applied to some modifiers. They often need to be centered at different positions within an object, which can be achieved by moving and rotating the coordinate system of the modifier using the Widget tool or Widget dialog . Different modifiers have independent widget coordinate systems. By default modifiers follow the local coordinate system , meaning that their widget coordinates are coincident with the local system until the widgets themselves are changed. But the coordinate center that a modifier refers to can be changed by changing the widget either interactively with the Widget tool or numerically by opening the Widget dialog from within the modifier panel. To open the Widget dialog click on the Widget Edit button at the bottom of the modifier panel. In the image on the right under the widget dialog the object mesh remains at the world origin, while the density distribution is off-center at the position of the widget . The widget itself is represented by arrows. Each modifier may have independent widget, i.e. local coordinate system positions. In the following image shows the application of the Displacement modifier , which moves only the mesh , not the coordinate system. The mesh container changed position, but the density distribution remained centered on the world coordinates. An additional fourth coordinate system is that of the observer or camera . These are the coordinates seen in the "shape view port" of the 3D Module and the rendered image in the Rendering Module . OPERATOR ORDER MATTERS! In the modifier stack several rotations, translations and other operators can be applied one after the other. The result of such combined operations, in general, strongly depends on the order in which they are executed. Therefore the order of the operator in the modifier stack is very important. For instance, translation can be combined in any order (they are commutative ), rotations among themselves and rotations together with translations can not. Coordinate Display Options Dialog: The Options Dialog that opens by clicking on the wrench icon on the menu bar of the 3D Module allows you to customize the display of a Cartesian coordinate mesh within the 3D views. It can helps as a reference during the modeling process. An example is show in the bottom image in the column on the right. A little experimentation should clarify the meaning and effect of the various parameters.

The Squish Modifier changes the distance of a vertex perpendicular to a plane (default: local xz-plane), The action is similar to the Squeeze Modifier , except that it´s planar, not radial around an axis. The Magnitude dialog allows you to define the squish amount as an Analytic Function of position along the reference axis. You can also use a Point graph where you can generate an arbitrary function by manually placing points and setting the spline interpolation. To do this, select Point from the Function drop-down list under the graph. The example graph on the right shows the way it was done for the example mesh displayed below. Widget: The Widget opens the Widget Dialog. It allows you to change the direction of the Squish Modifier. The purple arrow will indicate the direction of its action. Modifiers: Squish

Top of Page Overview General Considerations Computing Power Batch Processing Typical Modeling Applications Morpho-kinematic Modeling Photo-realistic Models 3-D Hydrodynamics Exoplanet transits Schematic illustrations Basic Workflow Need a new ShapeX feature? . Overview General Considerations Overview Your first question is likely to be: Is Shape suitable for my modeling problem? Here is a short summary of the types of problems that have been worked on with Shape and others for which we know that the software can be used. We shall also discuss the limitations that might prevent your problem to be attacked with Shape. General considerations: Polygon meshes: Polygon mesh objects are the most basic building blocks in Shape. The software generates them in a similar way as common 3-D animation programs such as the open-source Blender and many other commercial packages. However, these programs have been designed to model mostly opaque objects that surround us and hence compute their visual appearance according to the color assigned to their surface as a function of position and the lighting conditions. Only exceptionally volumetric effects are computed for clouds, fire or other phenomena that are not opaque. In astronomy and astrophysics almost everything is about gas and dust clouds that are at least partially transparent. Real surfaces are very rare and can be found only on rocky planets and other solid bodies. Some stars can be considered to have "surfaces" since the transition from the optically thin to thick regimes is very small compared to their size. The polygon meshes in Shape are therefore mainly used as containers of gaseous or dusty volumes, which are then assigned physical properties as a function of position within that volume rather than on the surface. Computing Power Batch Processing Computing Power: An old saying claims: "There is no such thing as too much computing power." This is also true for Shape applications that wish to push the limits of what is possible. But for many scientific applications today´s power of almost any laptop suffices. Since Shape is a highly interactive software, for your own comfort and an effective workflow make sure to use a mouse instead of just the mouse-pad. More sophisticated devices such as graphics tablets are of additional benefit for some applications. Most processes in Shape make use of parallel computing on multi-core CPUs. Especially the rendering processes and hydrodynamic simulations benefit from many-core CPUs and multi-threading. While the benefit of parallel computing mainly lies in reducing the time required for a computation, memory influences the spatial resolution that can be achieved in a rendering or hydrodynamic simulation. So, if you have ambitions to produce high resolution photo-realistic visualization and animations, then you might want to use a high-end workstation. Individual images can be rendered at high resolution with a special HD renderer that does not require a lot of memory. It does, however, have to do the full rendering process for each image. When you only need to change the camera view point for an animation or time series, other renderers only need to redo the last rendering step, because they keep the pre-processing information in memory, thereby speeding up the process. Batch processing can, at this time, not be done, e.g. as background processes on servers or supercomputers. This is a project for a future version. Typical modeling applications for astrophysics Morpho-kinematic modeling The original design purpose of Shape was the modeling of the 3-D morphology of nebulae using as additional constraint the kinematics observed in spatially resolved high resolution spectroscopic data. As the structure becomes more and more complex, the traditional approach of direct coding of the volumetric density or emissivity as well as velocity distributions becomes impractical. Therefore the technology of interactive polygon mesh construction as volume containers was adapted to astrophysical needs from conventional 3-D modeling in Computer Graphics. This type of modeling is still the flagship application of Shape. The user builds a 3-D volume distribution of density or emissivity, assigns a velocity field and then produces images, position-velocity diagrams and/or channel maps. This is the main approach for modeling the structure and kinematics of circumstellar gas, be it expanding or rotating, such as in planetary nebulae, supernovae or proto-planetary disks. An extension of this methodology is the application of carbon-monoxide (CO) radiation transfer using the ShapeMol module. This is useful to model high-resolution observations with the ALMA or other radio interferometers. A large number of scientific papers contains models of this type and can be referred to as examples. See the list of publications with Shape and Shape models. Morpho-kinematic Modeling Typical Modeling Applications Photo-realistic Models Beyond scientific application ShapeX can be applied to produce photo-realistic visualizations of a variety of nebulas, stars, galaxies and other types of objects. This type of application often requires a mixture of various modeling techniques, using polygon meshes, particles and hydrodynamics. Since high spatial resolution and substantial model complexity is likely to be required for this type of application, substantially more computing power and processing time might be necessary compared to more basic applications. More detailed information and examples of photo-realistic models, in particular with mixed techniques that include polygon mesh and hydrodynamics can be found in Steffen & Koning (2017) . Photo-realistic Models 3-D Hydrodynamics 3-D hydrodynamics The Hydro Module in Shape allows the simulation of basic astrophysical hydrodynamic phenomena at moderate spatial resolution (depending on the computing power in terms of CPU cores and RAM) solving the basic hydrodynamics equations. A simple radiative cooling scheme is included designed for fast computation above 10000 Kelvin. The details of the numerical scheme have been described in Steffen et al. (2013) . The novel feature of the hydrodynamics in ShapeX is that the user does not require programming the initial conditions. For this task the interactive 3-D polygon modeling interface is applied. The full integration of the hydrodynamic module in ShapeX allows a highly flexible analysis of the simulations and mixture with other modeling techniques. This yields very realistic visualizations for scientific and outreach applications. If you have been using a hydrodynamics code that is not part of Shape and find that your visualization and analysis software does not meet your needs consider Shape for it. You can import data from hydrodynamic simulations and use Shape to generate spectral kinematic output (P-V diagrams, channel maps) and images for any viewing angle. It is also possible complement your model with additional features constructed with Shape´s polygon mesh techniques for scientific modeling or illustration, and much more. Exoplanet transits Exoplanet transit lightcurves The lightcurves of exoplanets are a rich research field for which Shape is very well suited using its animation module for setting up the orbital motion, the rotation of the star with star spots and limb darkening or brightening. Shape can not reconstruct the systems parameters automatically from data, but the user can construct not only the time series of a single transit, but automatically vary a number of parameters and setups that allow the construction of a catalog of transit lightcurves and corresponding videos that shows the transit together with the lightcurve. In addition to the scientific value, the movies can be of use for outreach and press release illustrations. Schematic illustrations Schematic 3-D model illustrations The 3-D polygon mesh models can be used for schematic illustrations of model ideas, even if you are not interested in a physical model. For papers and presentations such models can not only be static illustrations, but as interactive demonstrations or movies they can be powerful tools to convince an audience of one´s ideas. Need a new ShapeX feature? Basic workflow: Interactively add the geometric elements of your object in the form of primitive polygon meshes (Primitives) that you can access at the top menu bar of the 3-D Module. These meshes will serve to encase the volumes that will constitute the different parts of the model. Then you modify the simple structure of the Primitives using what we call Modifiers, which give the objects new geometric structure and physical properties as a function of position in space. Using the Physics Module, you then assign the material and radiation properties to the meshes. Finally, the model is rendered with the Render Module and some of the observational properties can be displayed with the (Channel) Maps and Graph Modules, where the observational data can be included and compared with the model results. If the results are not satisfactory, the model will be adjusted until a satisfactory match is found between observations and model. Need a new Shape feature? Don´t hesitate to contact us , we might be able to help either by finding a solution with the current software or implement a new feature for you, thereby helping other potential users with similar applications. Basic Workflow

Filters for physical quantities in Shape can be defined here. Modules: Hydrodynamics Overview Hydrodynamic simulations are an important area of astrophysics. Shape is the first astrophysical tool to introduce an interactive mesh-based setup for such simulations without the need of programming or scripting by the user. Furthermore the results of the simulations can be directly incorporated in mesh-based renderings without the need of external software. From the hydrodynamics, just like any other mesh model, can be used to generate spectral information. Filtering using the Filter Module allows you to extract regions with particular properties based on the filter settings. Exporting of the hydrodynamic simulation data allows later incorporation of the data or parts of them into a completely different rendering project. The simulations in Shape are always intrinsically 3D on a uniform cartesian grid. The numerical algorithm in Shape was selected to run relatively fast in 3D with a minimum of variables to keep memory usage as low as possible, while still allowing to simulate the basic astrophysical phenomenology such as shocks and radiative cooling above a temperature of 10^4 K, typical to photoionized nebulae. The details of the numerical scheme used for the hydrodynamics, its limitations and example applications are described in the following research article: W. Steffen, N. Koning, et al., 2013, MNRAS, 436, 470–478 It is recommended to use numerical hydrodynamics tools in Shape or any other application only with sufficient understanding of the the possibilities and limitations of such tools. This module in Shape was made to make access to numerical hydrodynamics easier, but if you do not have insight into the potential artifacts the numerical schemes produce, especially at low spatial resolution, it is recommended to seek the assistance of someone who does. General Workflow The workflow involves three overall steps: First, you set up the elements of the simulation in the 3D Module. Second, the flow parameters are set up in the Hydro Module. The simulation is started and previewed here, too. Rendering and analysis is then done as usual in the Render Module vía a dummy rendering object that is set up in the 3D Module. See below for more details on how to set up a simulation in the 3D Module. User Interface The user interface of the Hydro Module consists of three main parts: The visual preview panels, the menu bar at the top and the parameter panel on the right. From the drop-down list at the top of the parameter panel you have access to four sub-panels: General, Flow, Boundaries and Camera. Menu Bar Calculate : The Calculate Button starts a hydrodynamic simulation. Preview : The Preview Button visualizes the initial setup of the simulation in the preview windows, where you can inspect the distribution of density, speed, temperature and pressure. Add : Add a new windows. You can add several new windows to the preview visualization area. This allows you to simultaneously supervise the evolution of different physical quantities or look at them from different viewing angles or filter conditions. Refresh : Refresh all views to the current state of the hydro simulation. Cascade & Tile : Select how to arrange multiple preview windows. They can also me manually arrange by clicking on the top bar and drag them around. Preview Preview : Each of the preview windows gets a new icon on the menu bar. Change the name in the camera parameters panel on the right to suitably represent the content of the window. Save & Load: Save or load the complete state of the hydrodynamic simulation for the current timestep. This allows you to stop the simulation at this time and restart the simulation where you left off after loading the data back with the Open button. The Open button opens the file dialog to select the previously saved file. Loading a file also allows you to use the result in a different project and render it with a different mesh based scene. After loading a data set click the Preview button on the Menu bar to see the simulation preview. How to set up a hydrodynamic simulation in the 3D Module Numbers that you need to start: The physical size of the computational domain in units of meters. Approximate densities (in particles/m^3) of background and active objects Initial velocities in km/s (in the 3D Module), which are then converted automatically to m/s in the Hydro Module and later back to km/s in the Render Module. Filters in the 3D Module require km/s, whereas those in the Hydro Module require m/s. The timescale on which the simulation is likely to finish in seconds (note that 1 year is approximately p x10^7 sec, which easy to remember) . Setup Render Module The first thing to do is to set the Scene Size and Resolution in the Render Module . Scene Size: The physical size from center to edge of the whole computing domain in meters (you may have to choose the correct units in the Units Tab of the Render Module). Resolution: The voxel resolution for the rendering. This does not need to be the same as the hydro simulation resolution with is set in the Hydro Module. Setup 3D Module Hydro Type: Each mesh object in the 3D Module has to be assigned a Hydro Type in the Hydro tab on the right. Background: The computing domain can not have any region that is completely empty. Therefore there has to be exactly one object with the type Background. The mesh of the background object has to enclose the full domain. Best to use a cube object with the size of the domain or larger. The background distribution of physical properties such as density or temperature may or may not be uniform as needed. Initialize: Object that receive all their properties at the beginning of the simulation and change only passively as a consequence of the simulation receive the hydro type Initialize. These could, for instance, be clumps or rings of high density gas. Boundary: Objects that are updated at every timestep or have to remain the same during the simulation are of type Boundary, since they act like a boundary condition. These could be stellar winds or jet that have to inject gas in a controlled, possibly time-variable manner. Variability is controlled in the Animation Module. Modifiers All hydro objects need to have at least one set of modifiers that describe their physical properties. These can either be [Density, Temperature, Velocity] or [Density, Pressure, Velocity] . Density, Temperature and Pressure must not be zero at any position in the domain otherwise the simulation will proceed only for a limited time or crash immediately. The Velocity may of course be zero. Other modifiers may be added as usual to control the shape, orientation and animation of the objects. Any of the modifiers may be animation including those for the physical properties. To some extent Boundary objects can be interactively moved around with the cursor or by changing numerical parameters while the simulation is running . Set up Hydro Module General Tab Grid Size: The number of cells in each direction of the cubic simulation domain. It is the same in all three dimensions. Note that the computational time and memory required for a simulation strongly depend on the Grid Size. While memory increases with the power of three , the required time increases as the fourth power of this grid size, not third power. This is so, because for smaller cells in the same physical domain the time step is also smaller. Therefore to reach the same final time, more time steps are necessary. So, ramp up this number from below, say starting at 64 and monitor memory and computing time as you increase the resolution. The numbers may be any number, no need to be multiples of 2. End time step: The number of time steps to be executed before the simulation is automatically stopped, unless the End Time is reach first. End time: The physical time in seconds after which the simulation shall be stopped automatically, unless the End Time Step is reach first. Resume: If a simulation as stopped or has been loaded from file, enable the Resume flag to continue the simulation. Click the Calculate Button on the Menu Bar to start resuming the computation. Animate: If Boundary Type objects in the 3D module vary in time in their properties, geometry or position/orientation via the Animation Module, then the Animate flag must be on for this time variability to take effect. Pause: Set this flag to temporarily pause the simulation. This can be useful to save the current state to file or generate a rendering of it in the Render Module. To continue the simulation remove the flag. Filters: For visualization purposes various filters can be selected from the drop-down list that select certain regions according to their physical properties. The filters themselves are set in the Filters Module. Note that SI units are used, including m/s for speed (in the 3D and Render Module the speed it in km/s, so different filters are required for the same filter range). You may combine more than one filter. Flow Tab Courant #: The Courant number is a number that controls the stability of the solution of the numerical differential equations of fluid dynamics. This so called CFL condition expresses that the distance that any information travels during the timestep length within the mesh must be lower than the distance between mesh elements. In other words, information from a given cell or mesh element must propagate only to its immediate neighbors. The number should be less than 1, recommended to be less than 0.5, depending on the particular conditions, incl. the strength of the cooling. Note that making the Courant # smaller, also decreases the time step and hence increases the total computing time. Gamma: The adiabatic index of the gas in the equation of state. For monoatomic gas the value is 5/3 (1.66). Eta: The numerical viscosity coefficient. This exchanges some fraction of the conserved physical quantities between neighboring cells and helps to maintain stability. The cost for the stability is diffusion, i.e. for instance high-density regions expand into low-density ones without the need of a pressure gradient. So, the value should be as small as possible, e.g. 1e-4 or smaller. High contrast regions are particularly affected. T0: The minimum temperature in Kelvin to be maintained if cooling becomes too strong within a timestep and would reduce the temperature below zero. For photoionized regions this value may be set to values of order 1e4 K. Otherwise to a reasonable lower value that represents physically plausible low values. Cooling: Enable or disable explicit cooling. See the paper by Steffen et al., (2013) for details. Cooling factor: Apply this factor to the explicit cooling calculation. Boundaries Tab For each side of the cubic domain the boundary condition may be set to Outflow or Reflection . If your simulation is symmetric with respect to a certain plain, then this plane could be one of the boundaries and then a setting of Reflection can be used. Most other applications will have an Outflow condition everywhere. The difference between the two conditions is only how the velocity components of the second to last cell is copied to the last cell. For the Outflow condition the component perpendicular to the boundary is copied as it is, whereas in the Reflection it is inverted. Camera Tab Controls the camera viewpoint and physical variable to be visualized in each preview window. Click on the preview window for which the parameters shall be shown and set. Name: Set the name of the preview window. It is convenient to set it similar to the physical variable to be displayed or some other name that somehow identifies the content. Variable: Select the physical variable to be visualized in the preview window. Note: When you move the cursor over the preview window a value for the physical quantity at the cursor position is shown in the top-left corner of the preview window. This is the integrated value along the line of sight. To see the local value use the Render Slice functionality (see below) to extract a single slice. Then the value shown represents the local value of the variable. Enable: Enable or disable this camera. Ortho: Enable or disable orthographic projection for this camera. Image: Edit the image display parameters for this camera. X Y Z pos: Set the camera position. The X Y positions are currently not functional. When the Ortho mode is disabled, the Z position in terms of the size of the domain (=1) changes the distance of the camera. X Y Z rot: Set the rotation angles of the camera per axis in degrees. The X & Y rotation can also be changed interactively by dragging the mouse over the preview window with the left button pressed. If the resolution of the simulation is small enough for your system, the preview responds interactively at a reasonable framerate. The interactive preview is rendered on the CPU and is therefore efficient only for relatively small resolutions. Render Slice In the Camera Tab you can scroll down to find the Render Slice controls. They allow you to display slices of the full simulation domain to closely inspect particular regions. The slices go along the coordinate axes. The initial position in terms of cell number are set with the sliders labeled X0, Y0, Z0, while the width of the slices are dX, dY, dZ. If you click on the slider handle a number field hopes that allows you to numerically set the value. It is convenient to set the Z width of the slices to 1 and the position to the middle. Then by enabling and disabling the Render Slice with the Enable flag, one can quickly change to a visualization that allows one to read off particular values in the preview window. As mentioned above the local value is only displayed in the preview window, if the width of the slice is set to 1. Otherwise the value shown for the cursor position is the integrated value along the line of sight, where each cell counts with a distance step of 1. For instance, if the integrated value along z is 200 and the domain resolution is 100, then the average local value is 2 along the line of sight at the position of the cursor. Output In the Camera Tab you can scroll down to find the Output section. When enabled it will output the full state of the simulation every dSteps timesteps. Choose a location on the filesystem afer opening the Directory selection dialog by clicking on the folder button. Make sure it is a location with sufficient disk space to accommodate the amount of data that will be saved. Status At the bottom of the Parameters Panel on the right there are three values updated at every timestep of a simulation. They help to judge the current status and rate of progress of the simulation. It show the current total Time in seconds, the current timestep dTime and the number of Step s computed so far. Considering the ratio between the total time and the timestep is very large, then the simulation will be progressing very slowly. This could be a hint to regionally problematic physical values.