Stella Version History

Newer versions
3.5.1 | 3.5 | 3.4 | 3.3 | 3.2 | 3.1 | 3.0 (Small Stella overview, Great Stella overview, full details)
2.8.7 | 2.8.6 | 2.8.5 | 2.8.4 | 2.8.3 | 2.8.2 | 2.8.1 | 2.8 | 2.7 | 2.6.1 | 2.6 | 2.5 | 2.4.5 | 2.4 | 2.3 | 2.2 | 2.1 | 2.0
1.1 | 1.0

Stella 3.5.1, 10th May 2006

• Just a bug-fix for some users who occasionally get a white area appearing around their toolbars.

Stella 3.5, 16th March 2006

Changes for Great and Small Stella:

• Changed "Set Face Color" to "Replace Face Color Throughout", which better describes its operation.
• Some of Bowers' abbreviations were entered as dual names rather than base names. All fixed now.
• Abbreviation "tid" now finds the truncated icosidodecahedron rather than the truncated dodecahedron. I think the most obvious abbreviation should be used instead of Bowers' abbreviation in this case.
• Fixed rendering problems on some computers with Intel graphics cards (built into the motherboard). Intel has bugs in their OpenGL implementation, which I've now managed to work around.

Changes for Great Stella only:

• "Options→Maintain Reflexibility" now also affects Shift+Left click in colour mode, like it does for Shift+C.
• Added "Color→Take Color from Neighbouring Faces". All faces of the selected face colour will receive a new colour from one of their neighbouring faces. Neighbouring faces with the original colour are ignored, but otherwise some options are presented if two neighbours have different colours. If any faces are completely surrounded by faces of the original color, the process is repeated until no further changes occur.
• Changed legend in Faceting Preview window. Only relevant items are shown, and a message that the faceting is complete is shown even if purple/red edges are still displayed (these are only warnings).
• Fixed the "Fit geometry to image" option which had no effect when saving an image of a 2D view.
• Fixed rare problem where some chiral polyhedra were thought to be reflexible. Caused problems for stellation, nets etc.
• Improved nets created when there are connected coplanar faces, eg subdivision of a convex surface.
• Fixed crash when facet is selected in faceting view and symmetry is changed.

Stella 3.4, 14th February 2006

Changes for Great and Small Stella:

• Renamed "Poly→Go to Variation". Now label depends on situation, either "Create Mirror Image" or "Create Pseudo Version". Also moved item to the top of the menu.
• Removed "Poly→Polyhedron Symbol" and it's matching toolbar button. This feature has been combined with "Poly→Polyhedron List", which now has an entry field for a polyhedron symbol, name, or abbreviation at the top.
• Changed built-in vertex descriptions from "4, 4, 4" format to the more standard "4.4.4" format.
• You may use symbols like "U30" now, same as "M30", but maybe a more standard form.
• You may enter Kaleido indices now to select a model. The symbols start with "K", like "K30". The Kaleido index is also shown in the "File→Polyhedron List" window.
• You may enter polyhedron names, substrings, or abbreviations in the new symbol field (eg T, C, O, D, I for Platonics, CO, ID, RD, RTC, PHC, THH, OHO, GCCO, SIRI etc).
• Added Jonathan Bowers' abbreviations as alternative names for uniform polyhedra. This means you can now enter them into the symbol field to select a uniform polyhedron.
• Added two new near misses, discovered by myself, to the list of built-in models. They have all equal edge lengths.
• Rearranged the near misses into a nicer order.
• Included <Up one level> in drop-down when a file is loaded. Lets you go up one folder.

Changes for Great Stella only:

• Added Jessen's Orthogonal Icosahedron to the library (in the Faceted section).
• Hidden faces are remembered when recalling a model from memory, adding from memory, and some other times.
• Handled coincident faces MUCH better. Hopefully it's very hard to break Stella now by giving it a model with coincident faces.
• Left and right arrow keys now cycle through OFF files as well as .stel files.
• Improved speed of augmentation with complex models.
• Fixed a bunch of bugs, including crash bugs, often relating to hemi-faces (faces which pass through the centre of the model).

Stella 3.3, 16th January 2006

Changes for Great and Small Stella:

• Added the ability to swap images between two faces in Image Mode (using Ctrl+Shift+Left-click).
• Improved rainbow mode a bit (made colours more saturated).
• Installation now sets the MIME type for .STEL files to "application/x-stella", which helps when attaching them to emails (some mailing lists would reject them previously).

Changes for Great Stella only:

• When giving an OFF file on the command line (or when double-clicking on an OFF file, if you have OFF files associated with Stella) it used to always open with a 2-view layout showing the polyhedron and its net. Now if "File→Save Default Scene" has been used, the layout from this default scene is used instead. This is useful if there might be a problem with the model and nets can't be created or would take a long time to create.
• Fixed bug where some models would give the error "ReorientAxes: Couldn't match all faces". Their nets and stellations could not be created.
• Fixed failure to stellate some tetrahedral-symmetry polyhedra with faces in planes that pass through the centre of the model.

Stella 3.2, 21st July 2005

Changes for Great and Small Stella:

• Added "Image>Fit Image Within Face", which fits an image completely inside a face. Also renamed the "Image>Fit Image to" submenu to "Image>Fit Image Around".
• Renamed "Image>Image Wrapping" to "Image>Image Boundaries".
• Added "Image>Image Boundaries>Border Around Image" and "Image>Image Boundaries>Set Border Color". Lets you have a border around images. The default border color is taken from the image's own border. A frequently-used color is used, or an average otherwise.
• Added "Image>Image Options", which opens a dialog box where most image options can be set. Move the mouse over each option to see a preview. Hopefully this makes it really easy to see what each option means. This window also appears after loading an image or an image list, allowing options to be chosen before the image is loaded.
• Added "Image>Options for All Images". Like above, but lets you change an option (or options) for all images at once.
• Right-click on these toolbar buttons for quick access to related features:
  • Show Vertices: opens small menu with two items:
    • Set the size for drawing vertices.
    • Set vertex color.
  • Show Edges: opens small menu with two items:
    • Set the line width for drawing edges.
    • Set edge color.
  • Use Spheres and Cylinders: open sphere and cylinder options window.
  • Image Mode: opens small menu with two items:
    • Image options.
    • Options for all images.
• Fixed: When loading an image list, if there were more faces than images, the last image would be repeated on all the remaining faces. Now the extra faces are left blank.
• Fixed: undoing image changes didn't work after then loading a new model.
• Fixed: great circles representing reflection planes are slightly larger to prevent them from ever cutting through a model (eg a high-frequency geodesic sphere).

Changes for Great Stella only:

• Augmentation preview can now display as solid, not just wire-frame. Default is solid.
• Added "Fit geometry to image" option when exporting an image.
• All settings used when exporting an image are now remembered between sessions.
• Export in VRML 2.0 format instead of VRML 1.0. Now VRML file provides several viewpoints.
• Fixed: OBJ export had bad normals, faces could be wound backwards, and didn't triangulate when it should.

Stella 3.1, 6th July 2005

Changes for Great and Small Stella:

• Added "View>Fit Geometry to View" submenu, to replace the "Fit" and "Fit All" items. New submenu contains four items:
  • Fit, Allowing for Rotation - like the old "Fit"
  • Fit All, Allowing for Rotation - like the old "Fit All"
  • Tight Fit - Fits the geometry as tight as possible.
  • Tight Fit All - As above, but for all views.
  Tight fitting is also used now when printing, to make the most of the space on the page.
• Shortcut "t" now means "tight fit" like above. "Shift+t" means "tight fit all". "Ctrl+Shift+t" means "toggle hide/show all", which was previously just "t".
• Added "Image>Load Image List" which loads a text file with an image file name on each line. All images are loaded onto different faces.
• Fixed occasional redrawing bug after menus are opened and closed for the first time.

Changes for Great Stella only:

• Delete key can now perform various functions, depending on the situation. It can cancel augmentation preview, delete a face created in faceting mode, or delete one part of a compound.
• When deleting one component in a compound, don't fit the new model to the window (retain the old zoom factor).
• Exporting a 3D model from the 3D Net view will now export the partically unfolded model, matching whatever is displayed in Stella.
• Exporting an incomplete model from the Faceting Preview view now works (used to crash).
• Exporting from all 3D views should work well now. For example, faces were not triangulated correctly when exporting from the dual-morph views.
• POV-Ray export improvements:
  • Fixed: when hiding all faces, they would appear again in export.
  • Changed: now all edges appear as cylinders even if all faces meeting at some edges are hidden. This matches what's displayed in Stella.
  • When not exporting with cylinders/spheres, leave in the lines to use them but comment them out (makes it easier to manually put them back in).
  • Fixed: size of spheres/cylinders in POV-Ray export was didn't match Stella when exporting from views other than the base view.
• Added section to manual about exporting images.
• Fixed framing of stellation face view (was too close).
• Fixed: printing stellation diagram with "same as window" option would not show the same area when zoomed in.

Stella 3.0, 12th June 2005

Small Stella 3.0 overview: (scroll down for Great Stella)

• Summary of main improvements: (scroll down for further detail)
  • Multiple undo/redo.
  • Put images on faces (JPeg, GIF etc) and print them on nets.
  • "Color Faces" mode to quickly copy colors/images between faces.
  • Display edges as cylinders and vertices as spheres.
  • Added library with new shapes (compounds and geodesic domes).
• Removed or changed items (users of version 2 will want to know about these):
  • Moved "Options>Edit Comments About Model" to "Edit>Comments".
  • Moved "Show Vertices" and "Show Edges" from the Display menu into the new "Display>Vertex & Edge Options" submenu.
  • Replaced "Nets>One Color per Net" with the "Nets>Net/Paper Color Mixing" submenu. See below for details.
  • Changed the image on the "Poly>Polyhedron Symbol" toolbar button from "5,5" to "J3". "5,5" was not a valid symbol anyway, although it was part of 5,5,5 for a dodecahedron. Probably the most common use is to enter a symbol for a Johnson solid, such as J3.
  • Moved the "File>Print Preview" toolbar button further to the left, which I think is more standard.
  • Renamed "View>Frame" as "View>Fit", and "View>Frame All" as "View>Fit All".
  • Got rid of toolbar button to open "Help>About" window. It's not needed often enough to warrant space on the toolbar. Use the menu instead.

Great Stella 3.0 overview:

• Summary of main improvements: (scroll down for further detail)
  • Multiple undo/redo.
  • Put images on faces (JPeg, GIF etc) and print them on nets.
  • "Color Faces" mode to quickly copy colors/images between faces.
  • Display edges as cylinders and vertices as spheres.
  • Easier file/library navigation.
  • More models in library (Brückner, Geodesics, etc).
  • Import models in .OFF format.
  • 9 memory slots and shortcut keys to set and retrieve memories.
  • Morphs between duals can now be exported and used as the new base model, allowing you to create nets for them.
  • Huge improvements to augmentation.
  • Huge improvements to faceting.
  • Zonohedra and geodesic spheres
  • Put models on faces/vertices of another model.
  • Stellation from an arbitrary set of planes.
  • Huge improvements in speed of many operations.
  • Export images as JPeg, GIF, PNG, etc.
• Removed or changed items (users of version 2 will want to know about these):
  • Moved the memory-related options from the Poly menu to the new Edit menu.
  • Moved "Options>Edit Comments About Model" to "Edit>Comments".
  • Moved "Show Vertices", "Show Edges", "Show Stellation Vertices" and "Show Stellation Edges" from the Display menu into the new "Display>Vertex & Edge Options" submenu.
  • Replaced "Nets>One Color per Net" with the "Nets>Net/Paper Color Mixing" submenu. See below for details.
  • Changed "Poly>Delete Component" to "Poly>Delete One Part of Compound".
  • Changed "File>2D Export>Export BMP" to "File>Export Image".
  • Got rid of "File>Open from library" and matching toolbar button. Used its toolbar image however for "File>Polyhedron List". These two features have merged in a way, as the list now includes the library.
  • Changed the image on the "Poly>Polyhedron Symbol" toolbar button from "5,5" to "J3". "5,5" was not a valid symbol anyway, although it was part of 5,5,5 for a dodecahedron. Probably the most common use is to enter a symbol for a Johnson solid, such as J3.
  • Moved the "File>Print Preview" toolbar button further to the left, which I think is more standard.
  • Renamed "View>Frame" as "View>Fit", and "View>Frame All" as "View>Fit All".
  • "Stellation>Maintain Reflexibility" has moved to "Options>Maintain Reflexibility". It applies not just to stellation, but also faceting and now augmentation, applying images to faces, and "Color>Set Face-Type Color".
  • Got rid of toolbar button to open "Help>About" window. It's not needed often enough to warrant space on the toolbar. Use the menu instead.

Version 3.0 in depth:
Changes affecting both Great Stella and Small Stella:

• Images:
  • Images and textures may be displayed on faces and are printed on nets. There is a new "Image" menu and Image mode to support this feature. In Image mode you can do the following:
    • Shift+Left-drag: move image.
    • Shift+Right-drag: scale image.
    • Shift+Left+Right-drag: rotate image.
    • Ctrl+Left-click: select face.
    • Ctrl+Right-drag: stretch image.
    All of the above also select a face and use it as the main face onto which its image is projected.
• Coloring:
  • Added "Color Faces" mode. In this mode, Ctrl+Left-click sets a face to the same color/image as the previously selected face. Shift+Left-click sets the color/image for all faces of a type. The clicked-on face becomes selected, but not highlighted in white, so that its color remains visible. Hold the left button down and drag across faces to color multiple faces, without re-clicking on each one. Select a face without changing its color by Right-clicking with either Shift or Ctrl down. The face is highlighted white, but only until you release the mouse button. If the selected face is hidden, other clicked-on faces are also hidden, rather than changing their color/image.
  • Added toolbar buttons for these items from the "Color" menu: "Set Face Color", "Set Face-Type Color", "Set Single Face Color", "Set All Face Colors".
• Display:
  • Added "Display>Vertex & Edge Options>Use Spheres and Cylinders" to display edges as cylinders and vertices as spheres.
  • Spheres and cylinders may have any radii and be displayed using any solid color, or one of the following special materials: gold, silver, copper, wood or stone. Set these options with "Display>Vertex & Edge Options>Sphere and Cylinder Options".
  • Sphere and cylinder options are remembered after you exit for next time you run Stella. Same goes for vertex and edge colors and sizes, and background color.
  • Added "View>Orientation>Default Orientation" to put the camera back to its default position.
  • Added "View>Orientation>Look at Selected Face/Vertex" and "View>Orientation>Sit on Selected Face/Vertex".
  • When resizing 2D views, the contents resizes too (like with 3D views), and the centre is kept central. Also improved saving/loading of 2D views in .STEL files so that they should better match when reloaded into a view of a different size.
  • Hidden faces were still displayed in 3D net view, now they are hidden.
  • Fixed case where model could gradually get smaller while rotating.
• Files:
  • Small Stella: Added library of extra polyhedra:
    • Compounds: 2 tetrahedra, 5 tetrahedra, 10 tetrahedra, 5 cubes, 5 octahedra.
    • Various geodesic spheres and hemispheres.
  • The green left and right arrow buttons (and left and right arrow keys) now cycle through all .STEL files in a folder if a file is loaded, rather than always using the built-in list.
  • Changed to a binary format for .STEL files (old files may still be loaded however). The new files are between 3 and 4.5 times smaller than before, and have compression built in.
  • Model names and dual names may now be edited and saved in .STEL files. Edit the names with "Edit>Base Name" and "Edit>Dual Name".
  • When saving a .STEL file, a default name is now filled in if the file hadn't yet been saved.
• Selection:
  • Select a vertex of a model using Shift+Right-click. Useful for seeing the matching vertex figure (or faceting diagram in Great Stella). You can see the vertex highlighted and the matching face highlighted in the dual view.
  • Double-click can now be used as a short-cut for Shift+click. Eg Double-Left-click to select a face, or double-right-click to select a vertex.
• Improvements to dual-morphing views.
  • Add new morphing method: morph duals by tilting triangles. This method is good for regular-faced models such as the Stewart toroids and Johnson solids.
  • Improved the morph by augmentation method. With many model it would have an obvious jump at the 50% mark. I have now generalised this method to avoid the jump.
• Undo/Redo:
  • Almost any operation (including file loading) can be undone with Ctrl+Z, "Edit>Undo", or by hitting the matching toolbar button.
  • Operations can be redone with Ctrl+R, "Edit>Redo", or by hitting the matching toolbar button.
  • Right click on the undo or redo toolbar buttons to open a menu of the last 20 operations. Select an entry to undo/redo multiple operations.
  • "Edit>Undo Settings" opens a window with various options for the undo mechanism. You may limit the amount of memory used, and the number of undo levels available.
• Nets:
  • Nets are created much faster in some cases, by avoiding the intermediate stellation step. Complicated geodesic spheres and Stewart toroids are examples that would have been too complicated previously, but are now usually within reach.
  • Added "Nets>Nets Shown in 3D View" submenu, which lets you choose which nets should be displayed in the 3D net view. Options are "Show All Nets" (the default), "Show One Type of Net" and "Show One Net".
  • Replaced "Nets>One Color per Net" with the "Nets>Net/Paper Color Mixing" submenu. Options are:
    • Auto: Automatically choose between the two options below. Mixed colors are used when the model is convex or has images on its faces. Otherwise only a single color is permitted per net.
    • One Color per Net/Page: Only allow faces of a single color in each net and on each page of paper when printing. Use this when you are printing onto colored paper, as I usually do.
    • Allow Mixing of Colors: Faces of different colors may be combined into single nets and printed onto the same pages. Use this if you want to use white paper and a color printer to fill in the face colors.
• New model info available:
  • Added polyhedron density to Info window.
  • Added solid angles of faces to Info window.
  • Added "Scale>Base Polyhedron Inradius" and "Scale>Dual Inradius" to set the distance of the selected face plane from the model centre.
• Miscellaneous:
  • Right click on various items in the Info window to get a one-entry menu allowing you to edit that item. Eg model name, comments, radius, midradius, volume, etc.
  • Left or right click on the icon at the top left of any view to open a menu of all view-types. Select another entry to change the view-type.
  • Mouse wheel now zooms in or out on the view under the mouse, rather than always zooming on the selected view.

Additional changes for Great Stella only:

• Files:
  • Added lots of models to the library provided with Great Stella, including all of Brückner's 1906 polyhedra (except for ones with dihedral symmetry) and an assortment of geodesic spheres and hemispheres.
  • List of built-in polyhedra now also shows files and folders from the Stella library. You may add your own files into this library to include them in the list.
  • Import external files in OFF format, provided they are proper polyhedral surfaces (even number of faces per edge). OFF is a simple text format, see http://www.geomview.org/docs/html/geomview_41.html.
  • Load large .STEL files *much* faster. One example 5 Megabyte .STEL file originally took almost 6 minutes to load, now it takes about 2 and a half seconds.
  • After various operations, a guess is made at the name of the new model (eg "Faceted Dodecahedron" after faceting a dodecahedron). Edit the names with "Edit>Base Name" and "Edit>Dual Name". Names are saved in .STEL files and remembered when putting a model into a memory slot, and displayed in the memory menus to identify the models in each slot. They are also displayed in the augmentation dialog box.
• Memory slots:
  • Stella now has 9 memory slots for models rather than 4.
  • New keyboard shortcut to put a model in memory (M) and to retrieve a model from memory (Shift+M). After M or Shift+M, type the number of the memory slot to use (1-9), or click on the appropriate button, or hit Enter to use slot 1.
• New ways to create and edit models:
  • Morphs between duals can now be exported, put in memory, and used as the new base model, allowing you to create nets for them.
  • Create zonohedra based on the current model using "Poly>Zonohedrify".
  • Models can be put on faces/vertices of other models using "Poly>Put Models on Face/Vertices" (or keyboard shortcut "p" or matching toolbar button). Similar to augmentation, but faces don't have to match, rather it simply places the new model on the face or vertex (without connecting any geometry between the two). Good for creating fractal polyhedra, or just to make some interesting designs.
  • Geodesic domes may be created based on almost any polyhedron, even self-intersecting ones!
  • Project vertices of a polyhedron onto a sphere using "Poly>Project onto Sphere". Only permitted when the resulting faces would still be planar.
  • Added "Poly>Subdivide Faces".
  • Added "Poly>Create X x Y x Z Block", which is like augmenting a whole bunch of cubes together into a larger block. Also has toolbar button.
  • Non-uniform scaling of models with "Scale>Non-Uniform Scale". Lets you stretch or squash models.
  • Added "Poly>Keep One Part of Compound".
• Augmentation:
  • Added toolbar button for "Poly>Augment Polyhedron".
  • When augmenting, the camera no longer changes. Previously the orientation and zoom factor could change.
  • Augment using any built-in model or dual.
  • Augment using a model from a .STEL file.
  • Augment using antiprisms or crossed antiprisms (requires regular face).
  • Augmentation using a pyramid no longer requires a regular face, nor a face where N/D < 6.
  • Wire-frame preview is now shown when augmenting using a pyramid, cupola, prism or antiprism. Orientation of cupola may be selected during preview.
  • When using a pyramid, cupola, prism or antiprism, height may be set interactively during preview (Ctrl+Left-drag).
  • When using a cupola, prism or antiprism, the size of the top may be set interactively during preview (Ctrl+Right-drag).
  • Prism height choices: average, shortest or longest edge length.
  • Pyramid height options: guess, same edge lengths, face radius or face diameter.
  • As before, left and right arrows cycle through different orientations for the added model. Now up and down arrows also have a function, letting you try different matching faces of the added model (not permitted for pyramid, cupola, prism, antiprism).
  • Added option to augment all faces of same shape and size, or same shape and any size.
  • Added option "Only faces of same color" to only augment faces of the same color as the selected face. For example, you can use "Color Faces" mode to quickly color a bunch of faces the same way, then augment just those faces.
  • Added choices for coloring the added model:
    • Choose a specific single color.
    • Inherit colors from faces being augmented.
  • Augmentation now makes use of the "Options>Maintain Reflexibility" setting. When enabled, mirror-image faces will be augmented in unison.
  • When augmenting a dual model, and there are no base model views, the dual view is changed to a base view, so you can see the result.
  • A warning is given when augmenting to all faces of same type and symmetry would be lost.
  • Fixed bug where sometimes augment/excavate would behave the opposite way around.
• Stellation:
  • Stellation from an arbitrary set of planes is now possible using "Stellation>Stellation Planes"
  • Added "Stellation>Auto-frame Changed Stellation". When enabled, the stellation and stellation face views will be framed (so that the contents fits nicely) whenever the stellation changes. It is enabled by default. Now you can hold down the Up arrow and watch the stellations go past without growing too big for the screen.
  • Added "Color>Stellation Diagram Color Scheme>Color Per Front/Back" which uses a very simple coloring for the stellation diagram, only shading parts visible from front or back.
  • Give warning before stellating a very complex model (often required in order to generate nets). Gives the user a chance to abort the stellation.
  • Selected cells remain more visible now when zoomed out on cell diagram.
• Faceting:
  • New 2D faceting diagram view. The faceting diagram is reciprocal to the stellation diagram.
  • New 3D faceting preview view.
    • Shows what faceting will look like.
    • Edges with other than exactly two faces are highlighted. Green edges have only one face. You need to create another. Red edges have an even number greater than two. Might be a mistake, or might be deliberate. Orange edges have an odd number greater than 2. You should add or delete faces at these edges. Purple edges have exactly two faces, but they are coplanar (which may be intentional, but is often a mistake).
    • Ctrl + Left click to select a facet.
    • Hit "X" button to delete it. You can also use the "X" button in the 2D net view to delete a displayed facet (use PageUp & PageDown to find the facet).
    • Left-and-down arrow button creates faceted model.
  • Auto-complete button appears in "Create Facets" mode (labelled "..."). Click this to auto-complete a facet you have started. Keyboard shortcut: ".".
  • Use whole existing face as a facet by using Ctrl + Right click in facet mode.
  • Hit Backspace or Shift + Left click on most recent (or previous) point in partial facet to delete last point.
  • Facet preview model can be put in memory (if complete).
  • More checks are now done when creating a faceted polyhedron to avoid invalid polyhedra.
• Display:
  • Added "Edit>Text for Face/Vertex" (shortcut Ctrl+T) to enter text that will be displayed on the currently selected face/vertex. Also "Display>Show Face/Vertex Text" to display or hide this text. Text is remembered in .STEL files.
  • Edges can now be displayed for models with infinite vertices.
  • Added "Display>Show Intersections with Spheres", which lets you define one or more spheres of arbitrary radius to be displayed (as wire-frame). Intersections with these spheres are shown and printed on nets. This feature was added to help make Rubik's Cube-style puzzles from paper, the arcs of intersection representing grooves or tracks that will be required. Hopefully it has other unforeseen uses.
• Miscellaneous:
  • When exporting an image of a view, there are options to open the saved image after saving, and to set the JPeg quality. Images may now be saved in a variety of formats (JPeg, GIF, PNG, TGA, BMP etc).
  • After creating a Waterman polyhedron ("Poly>Create Waterman Polyhedron"), the green left and right arrow buttons move through the list of other Waterman polyhedra.
  • New button lets you convert the model in most 3D views to become the base model (including morph views, 3D nets is the only exception).
  • When selecting a base+dual or morphing view, message appears in net views saying how to get nets for those models.
  • Fixed: Stella failed to recognise a reflection symmetry in some models with no rotational symmetry.
  • Fixed Waterman polyhedra using cubic packing. Since nearest neighbour sphere was only half as far away as with rhombic dodecahedral packings, some models were missed.
  • Lots of other fixes and stuff I've forgotten!

Stella 2.8.7, 16th November 2004

Fixed a bad bug where creating nets or stellations of models whose face-planes passed through the model's centre would crash. For example the "Drilled Square Bicupola" from the "Stewart Toroids" category in either Small or Great Stella, or the Tetrahemihexahedron in Great Stella. The bug only first appeared in version 2.8.6.

Stella 2.8.6, 28th October 2004

Great Stella only: Fixed crash when loading some .stel files containing faces with many sides (eg about 70 or more).

Default to check for updates daily instead of weekly. The check is done in a separate thread, so there's no delay while checking.

The check for updates now reports changes specific to your product (Great Stella or Small Stella), rather than reporting changes to both.

Stella 2.8.5, 18th July 2004

On some systems, Stella failed to notice when an internet connection was available, but still spent 5 seconds looking for it. If you see this message, then you don't have this problem.

Searching for updates is now done in the background, so even with a slow internet connection the program will start straight away.

Fixed a rare case where Stella could crash (found by George Olshevsky).

The progress meter can now give estimated remaining time in millennia, when appropriate :-)

Stella 2.8.4, 20th June 2004

The items on the "Color>Special Color Arrangements" submenu had stopped working. Fixed now.

Automatically check for new versions of the software if an internet connection is present. Option to check daily, weekly, or monthly, or never to check at all.

Software now refers to the new web site.

Stella 2.8.3, 26th April 2004

The items on the "Color>Special Color Arrangements" submenu had stopped working. Fixed now.

Stella 2.8.2, 5th April 2004

Great Stella only: creating a faceted polyhedron could crash when the model would not be valid. Now it gives an error when an odd number of faces meet at some edges, and a warning when more than two faces meet at an edge or adjacent faces are coplanar.

Stella 2.8.1, 5th April 2004

Changes for Great and Small Stella:

• Fixed: vertex figure of dual could say "vertex 29 of 24".
• Labels along vertex figure edges are now drawn 45% of the way along the edge rather than half way, to avoid likelihood of labels being drawn at same position where edges cross.

Changes for Great Stella only:

• When displaying vertex numbers on 3D model, they were drawn over each other for coincident vertices. Now they are given as a list, eg "11,23".
• Augmenting with a prism/pyramid would recolour the resultant model if it was a compound, regardless of the "Keep colors from original models" setting.
• The augmentation setting "Keep colors from original models" now tries to keep dual colours too.

Stella 2.8, 1st April 2004

Changes for Great and Small Stella:

• Angles within faces may be displayed on-screen in 2D and 3D net views using "Nets>Show Face Angles".
• Added "Selection>Select Vertex by Index"
• Changed "Selection>Deselect Face" to "Selection>Select None", and gave it the keyboard shortcut "n".
• After selecting a face, a message like "Selected base face 67" appears in the status bar.
• Faces can be selected now by Shift+Left clicking an edge of the vertex figure. The edge for the selected face is highlighted.
• Changed items on "Color>Basic Color Scheme" submenu:
  • First group of options are mutually exclusive like before:
    • "Auto Color": Let Stella decide how to color the polyhedron. This has changed slightly. Compounds are coloured as compounds. Otherwise we colour according to face type. If there's only one face type, we colour the front and back of faces differently to make it a bit more colourful. If there are greater than 5 face types, then chiral pairs are coloured the same way to reduce the number of colours and highlight reflection symmetry.
    • "Use a Single Color": Use one colour for the whole model.
    • "Color Faces by Number of Sides": All triangles will have one colour, all quadrilaterals another colour, and so on.
    • "Color by Face Type": Each type of face gets its own colour.
    • "Color per Face (Unless Parallel)": Every face gets its own colour, unless they are parallel, in which case they share a colour.
  • Second group of options may be enabled independently. They are all available when colouring by face type, otherwise some of these options may not be available (as appropriate).
    • "Same Color for Chiral Face Pairs": Faces which are enantiomorphs of each other will be coloured the same.
    • "Same Color for Coplanar Faces": Coplanar faces will always be coloured the same.
    • "Same Color for Coplanar Chiral Pairs": Faces which are coplanar and enantiomorphs of each other will be coloured the same.
    • "Same Color for Front and Back of Faces": The front and back of each face will be coloured the same.
  • Final group contains just one item:
    • "Toggle Single/Auto Color Modes". Keyboard shortcut: Tab. To switch between single and auto colouring modes.
• Changed how keyboard shortcuts are shown in menus. Now letter keys are always given as upper case, possibly with "Ctrl+", "Shift+" or "Ctrl+Shift+" before them. Previously you had to take notice of the case of the letter to know whether to use Shift or not, which was confusing.

Changes for Great Stella only:

• New menu item "Options>Show Dual Face on Vertex Figure". It is on by default. Disable it to hide the dual face diagram from the vertex figure view.
• New submenu "Options>Label Vertex Figure Faces with" has following items:
  • "Nothing" - Do not label vertex figure at all.
  • "Number of Sides" - Faces (shown as edges) in the vertex diagram are labelled with the number of sides of that face (eg "4" for a square). This is the default, and was previously always done.
  • "Face Indices" - Label faces with their index number.
  • "Index Around Vertex" - Label faces according to their order around the vertex ("1", "2", "3", etc).
• Coplanar faces of smaller area are now always rendered on top of those with larger area, to ensure they are visible. Made other improvements to coplanar face rendering too.
• When selecting a face with the mouse and several faces are coplanar, the one that is displayed on top is now always selected first. Selecting again will cycle through all the coplanar faces at that point.
• Sometimes selecting a face with the mouse chose the wrong face when a model had many faces (eg yog-sothoth). Now it always works.
• Added "Color>Set Whole Component Color" to set the colour of one component in a compound.
• Faces are no longer recoloured when deleting a component from a compound.
• Added keyboard shortcut to create faceted polyhedron: Ctrl+Shift+F.
• When exporting files (VRML, POV-Ray, etc) a default file name is provided.
• Faces no longer appeared when exporting from stellation view to OBJ, VRML, or POV-Ray.
• Changed DXF export so that Bryce will be happy with the files.
• OFF format now supports colour.
• Fixed a bunch of things relating to subsymmetry groups.
  • When a model had pyramidal symmetry, its subsymmetry reflection groups were wrong.
  • Symmetry groups requiring rotation-reflection didn't work.
  • Changing to a subsymmetry group during augmentation preview could look wrong.
  • Selected face now stays selected when changing to a subsymmetry group.
  • Fixed bug where changing back and forth between various subsymmetries could eventually cause problems.
• Don't display two errors sometimes when faceting is illegal.
• Some edges didn't show up in face view.
• Degenerate dual faces (with no area) caused bogus faces to be displayed sometimes.
• Fixed bug when five or more facial planes intersected at a line. Stellation was OK, but failed to select all the right cells sometimes to recreate appearance of original model.
• Faceting failed when a pentagon and pentagram sharing the same vertices were both present.
• Fixed stellation stuffing up sometimes for very complex models. It would keep operating as if everything was OK, but the wrong original cells would be chosen, so nets were for the wrong model.
• New diagnostics available on the "Options>Diagnostics" submenu: "Show Face Numbers", "Show Face Type Numbers", "Show Vertex Numbers" and "Show Vertex Type Numbers".
• "File>Print Test Page" now draws a ruler right across the page horizontally and vertically so you can see how accurate your printer is.
• "Display>Show/Hide Faces Around Vertex" will now ask whether to also include other coincident vertices if there are any. Also tells you the indices of those vertices.
• Fixed "wiggly" stellation lines for very complex stellation diagrams when zoomed in a long way.
• When printing a 2D view, framing "Same as in window" wasn't quite the same.
• Changing from morph view no longer stop morphing unless it was the only such view. Same for 3D net folding.

Stella 2.7, 1st December 2003

Changes for Great and Small Stella:

• Fixed: Stella would say it was unlicensed after changes to daylight saving time on Windows 2000 and NT (was actually a Microsoft bug). Fixing this meant a change to the way licensing worked, so everyone must now re-license the program using their original license files. I can send these again to anyone who no longer has it.
• When exploding a model apart with Ctrl+Shift+LeftMouseDrag, you can release the mouse button while dragging to see the exploding continue on its own. It oscillates back and forth out to the point where the mouse button was released.
• Added mitre angles for people building polyhedra from wood. These are available wherever dihedral angles are available:
  • "Nets>Show Edge Data>Mitre Angles"
  • As an option in the "Printed Data" section when printing nets
  • In the metric data file created with "File>Export Metric Data" (Great Stella only)
• Improvements for vertex figures:
  • These were mostly displayed wrong for non-uniform polyhedra.
  • Vertex figure for one of the current model's vertices is always shown now. Used to often show the vertex figure for the dual.
  • Fixed vertex figures for infinite vertices.
  • Added "Options>Show Coplanar Vertex Figures" to display all coplanar vertex figures at once. It is on by default. Previously only one face cycle was shown at a time. (Great Stella only)
  • Each cycle is shown in a different colour.
  • Matching vertex-figure/dual-face pairs are in same colour, but vertex figure is drawn with thicker lines.
  • Fixed bug where it would sometimes say "Vertex type 2 of 1" and not let you select all the vertex figures.
  • Circle shown is now intersection between reciprocation sphere and dual-face plane. This means that vertex figure and dual face are reciprocal about this circle. Exception is when vertex is inside sphere. Then intersection gives circle with imaginary radius. Mathematically this still works though, just requires an inversion in addition to the reciprocation.
• Lines of edge data text on printed nets were squished together too close.
• Using "Poly>Go to Variation" on rhombicuboctahedron still said "Octahedral" symmetry.
• Fixed folding half-way (by Ctrl+Right mouse clicking in the 3D net view) on a model with only one big net.
• Fixed: in the net for the great inverted snub icosidodecahedron with "Nets>One Color per Net" disabled, some parts were not coloured. Also happened for some mainline stellations (Great Stella only) of a dodecahedron with a dodecahedron augmented to each side.

Changes for Great Stella only:

• In measurement mode or when creating facets, you can now select vertices in the stellation diagram (2D or 3D), and the original face and stellation face diagrams. Measuring line and partially created facet are now shown in these diagrams when they lie in the same plane.
• Problems with coplanar faces:
  • Only one coplanar face showed through other faces when selected.
  • Could get "2 of 1" in base and stellation face views.
  • Stellation face view showed nothing when coplanar.
  • Base face and stellation diagram views were framed wrong for coplanar faces.
• When trying to create a faceted polyhedron from an invalid set of facets Stella could crash. Eg after creating a square facet in an octahedron. Now an error is given.
• Fixed: Finding which original stellation cells were required to create the base model didn't work when some colinear edges within a face overlapped each other.
• Crashed when stellating models with face planes through the model's centre and the centre of the stellation diagram was not entirely surrounded by finite 2D regions.
• Got rid of three items from Poly menu: Add One Vertex at a Time, Add Vertex, and Remove Vertex. They were of no use to anyone.

Stella 2.6.1, 6th June 2003

Changes for Great and Small Stella:

• Fixed bug where not all hidden faces were remembered correctly when saving and reloading STEL files.

Changes for Great Stella only:

• Now when exporting VRML file and other 3D formats, hidden faces are not exported.

Stella 2.6, 3rd June 2003

Changes for Great and Small Stella:

• Added "Options>Lock 3D Views Together" and matching toolbar button. When set, orientation, zoom and other viewing parameters are locked between all 3D views. So rotating the model in one view will rotate it the same way in all the views.
• Added a toolbar button for "Color>Rainbow Color Mode".
• "Poly>Go To Variation" will now work for any chiral model, changing to its enantiomorph.
• Fixed: Couldn't cut edges in base view anymore.
• Fixed: When the basic color scheme was set to "Auto" and the model was a compound, special color arrangements didn't work anymore.

Changes for Great Stella only:

• Added "Poly>Delete Component" to delete one component from a compound.
• Fixed bug where cutting mode would crash after going to a sub-symmetry.

Stella 2.5, 9th April 2003

Changes for Great and Small Stella:

• STEL files now remember which faces are hidden.
• The user may now add their own comments about a particular model using "Options>Edit Comments about Model". They are saved in the STEL file, and appear in the Info window.
• Browse path is now remembered between sessions.
• Default views are now base model and 2D net, rather than base model and dual.
• Default view types initially used in the different layouts are better now (ie not all the same!), and view types for each layout are remembered when changing between layouts.
• Changed "File>Save Default Layout" to "File>Save Default Scene". It saves more than just the layout.

Changes for Great Stella only:

• Added "Stellation>Show Cell Lines" to show stellation cell lines on all faces at once. There is also a new toolbar button for this. Cell lines will even be printed on nets, in case you want to build a model showing all the facial-plane intersections. This setting is saved in the STEL file. Added "Color>Set Cell Line Color" to set their color (default is black, to contrast with white edges).
• Added new Stewart toroids discovered by Alex Doskey and myself to the Polyhedron Library.
• Added "File>Open from Library". Like "Open", but always starts at the root of Stella's Polyhedron Library.
• Added link to my paper "Stella: Polyhedron Navigator" from the Help menu.
• Fixed normals exported to OBJ and OFF formats.
• Fixed: stellation failed for some tetrahedral models with hemi-planes.
• Fixed: some sub-symmetries of tetrahedral and octahedral symmetry had wrong reflection symmetries.
• Fixed bug with some sub-symmetry groups, eg cubohemioctahedron and 4-fold dihedral sub-symmetry.
• Improved face-colour storage in STEL files to reduce their size.

Stella 2.4.5, 11th February 2003

• Demo version will now let you nets for the Platonic solids.
• Fixed some other little bits and pieces.

Stella 2.4, 20th January 2003

Changes for Great and Small Stella:

• SWAPPED mouse controls for Zoom and Twist! "Options>Old-Style Mouse Navigation" may be used to retrieve the old behaviour instead, but I think the new way is better.
• Finally added orthogonal projection for viewing models! Try "View>Orthogonal View".
• New data in info window:
  • Genus
  • Orientability
  • Volume
• Reworked "Scale" menu somewhat, and added items for setting the volume of a model.
• Added "Options" menu and moved some stuff onto it from other menus.
• Coloring/hiding options have been updated. There is new functionality and some keyboard shortcuts have been changed. See the "Color" and "Display" menu for what's new and different.
• Added ability to set line width for print-outs. Lines on some printers are very thin and hard to see otherwise, especially on dark paper.
• Fixed bug where number of edges to score/fold was wrong in Info window.

Changes for Great Stella only:

• When exporting a model from the base or dual view, the original complete faces (and edges) are now exported. This means stellation is not required and the model will export almost instantly. Exported files may also be considerably smaller for models that self-intersect a lot.
• When exporting VRML with edges, same edge colour is used as in Stella.
• Added Waterman polyhedra. See "Poly>Create Waterman Polyhedron".
• Augmentation now always goes the direction you expect, ie adding to the model when augmenting, and subtracting from the model when excavating.
• When using auto-colouring, compounds will now be coloured with one colour per component.
• New data in info window:
  • Number of components in compound.
  • Number of faces/verts/edges, genus & orientability is given for each component.
• Added "Options>Recolor Sub-Symmetries", to decide whether the model should be re-coloured or not when dropping to a sub-symmetry group (previously it always was).
• Fixed crash when stellating very complex models.
• Canceling stellation leaves the model in a better state now.
• DXF export works better now (for AutoCad).
• Stellations of the octahedron and icosahedron from Wenninger's Polyhedron Models can now be created in the demo version of Great Stella simply by using "Poly>Polyhedron Symbol" and entering something like "W40" to get model number 40 (this worked in the full version but not the demo before).

Stella 2.3, 30th November 2002

Changes for Great and Small Stella:

• "Stellation>Stellation Info" has been replaced with "View>Model Info" and there is a new toolbar button for it. It is now available in Small Stella as well as Great Stella. The Info window is more useful now, having info about the model such as number of faces/vertices/edges. It can remain open while using the program, and can be docked to the main window or floated separately.
• Mouse wheel can be used to zoom in and out (except on Win95/98)
• Rearranged toolbars. Now category and current model are shown in toolbar as drop-down lists. You can use them to easily change to another model.
• Changed to flat-look toolbars, which looks a bit less confusing when there's so many buttons, and takes less space.
• Toolbar dockings and positions are now remembered between sessions, and docking/floating works better than before.
• When Stella folds/unfolds a model, and there's only one net, it now "bounces" sooner, so that the model doesn't appear static for a while.
• Improved efficiency when displaying edges in some cases.

Stella 2.2, 4th November 2002

Changes for Great and Small Stella:

• Implemented a new method for rendering coplanar features, eg edges around faces, or two overlapping coplanar faces of different colours. With no special treatment, such features will flash. The previous method for resolving this had problems in some cases, such as parts of hidden edges showing through. The new method uses OpenGL's stencil planes. It produces perfect results in all cases, but may be slower depending on hardware. The choice of which method to use is now available from the "Display>Coplanar Rendering Method" submenu.
• Give warning when the system has only a 16-bit Z-buffer. Changing display settings will improve images in this case.

Changes for Great Stella only:

• When exporting, there are some new options:
  • POV-Ray, VRML, DXF: Export edges or not?
  • POV-Ray: Export vertices or not?
  • POV-Ray, VRML: Launch POV-Ray/VRML viewer after exporting.
• Fixed: Different coloured faces of the same type were not exported to POV-Ray properly.
• When the model is unnamed, use name of file in window titles and titles of printouts (the path and extension are omitted).
• When using "Keep colors from original models" during augmentation, and using one of the built-in augmentations (not from memory), the colour of the new model is taken from the original face being augmented.

Stella 2.1, 18th October 2002

Changes for Great and Small Stella:

• May now enter "W41" or "#41" etc in the polyhedron symbol box to jump to models from Wenninger's book Polyhedron Models (including stellations in Great Stella!). Can also enter Wythoff symbols now, and "M53" etc to use the index from Maeder's list of uniform polyhedra. (Small Stella still doesn't support the nonconvex uniform polyhedra).
• Added two more Near Misses.
• Added option to display sphere used for reciprocation.
• Added "File>Save Default Layout", which saves the current layout and model as a default. Whenever you start Stella after that, it will start off with this layout.
• Overlapping coplanar faces of different colours should no longer "flash" the way the used to (this was most noticable for compound models in Great Stella).
• Added the "Display>Polygon Filling Method" sub-menu. This affects how self-intersecting polygons are filled in.
• Fixed: after rotating models for a while they would gradually start to move forward, backward, or sideways.
• Fixed triangulation used for displaying faces in some cases.
• Framing didn't work properly when using cross-eyed/wall-eyed 3D views.
• Improved method for finding radius of sphere for reciprocation.
• Improved default orientation for some pyramidal-symmetry models (eg J8).
• Fixed crash when loading some old STEL files with a single view layout.

Changes for Great Stella only:

• New augmentation options: keep color from original models (now the default), and only preview when there's more than one orientation.
• Rearranged "Poly" menu a bit, moving less used items lower down.
• Cyclicly connected nets may now be generated (eg see compound of two great dodecahedra, dual of SmallStelDod_2.stel in library).
• Renamed files in "Compounds" folder of polyhedron library and added many more models, including 20 tetrahemihexahedra.
• Fixed stellation for some models that had problems, eg FacetedCube.stel or TetraHemiHex_5.stel in library.
• Fixed: sometimes augmentation thought there were more possible orienations than there really were.
• Fixed rare bug where nets could overlap themselves.

Stella 2.0, 12th September 2002

Changes for Great and Small Stella:

• New built-in models for Great and Small Stella: Johnson solids, "Near Misses", arbitrary regular-faced prisms/antiprisms (convex only for Small Stella), Stewart toroids, and Stewart's G3, Z4, X and K4'.
• The symmetry group of any model can now be found algorithmically. The name of the current rotational and reflective symmetry group is given in the top toolbar.
• Added menu option "Stellation>Maintain Reflexibility".
• Export BMP images from a window, with optional over-sampling.
• Added more buttons to the toolbars, and added a new toolbar. Toolbar button images are now also displayed beside their matching menu items for easy cross-reference. Some buttons also appear in the title bar of each view now.
• Dual morphing techniques have been updated to make them work better for the wider range of polyhedra that are now available. The "tilting triangles" method could not be generalised and has been replaced by the "tilting quads" method, which is a nicer variant, and can be generalised to more models.
• Fixed colour export for VRML, POV-Ray, and OBJ.
• Fixed that single-colour mode was lost when going to a new model.
• Can now set colour for edges/vertices, width for edges, and size for vertices.
• Fixed bug causing less than optimal net layouts on printed pages.
• Cell diagrams printed better now.
• Numerous other little fixes and improvements that I've forgotten about!

Changes for Great Stella only:

• New built-in models for Great Stella only: Skilling's figure, and arbitrary regular-faced pyramids, cupolae, cuploids and cupolaic-blends.
• The BIG new features in Great Stella are: faceting, and augmentation/excavation/drilling.
• Sub-symmetry groups are supported, which affects stellation, faceting, and augmentation/excavation/drilling.
• Compounds of models and their duals or enantiomorphs may now be created along with nets.
• Create convex hulls.
• Added four memories for temporary storage of a model. Can be used with augmentation to augment using the model in memory.
• Added support for Miller's rules, and primary stellations.
• Reflection symmetry planes may now be displayed as great circles in the reflection plane. Use 'r' to toggle display.
• When showing symmetry axes (hit 's'), symmetry points are shown in stellation diagram too.

Stella 1.1, 14th January 2002

• Added Rainbow mode, for Mathematica style colouring.
• Added much more powerful colouring tools. Now you can have different colours on faces of the same type, and use the colouring arrangements described in Polyhedron Models.
• When a stellation happens to be a compound of simpler convex models (eg five tetrahedra), you can highlight each part in a different colour (unless some faces from different parts are coplanar, eg ten tetrahedra).
• The guides have been updated to describe all the colouring options.
• Edge lengths or dihedral angles may now be displayed on the nets.
• Demo version of Great Stella now allows stellation of the icosahedron, which gives a much better idea of how it works and what's possible.
• Give a helpful message in a few situations, such as entering one of the dual-morphing modes, or one of the mouse-selection modes.
• More keyboard shortcuts for various menu items (shown on the right hand side of the menu items).
• The installation process now checks whether you have the required DLLs.
• There was a bad bug when starting with "8/3, 4, 8/5, 4/3" then hitting the Down arrow twice. Fixed now. It was a very rare situation.
• Fixed a couple of minor bugs when creating nets.
• Fixed that Ctrl+Left click to remove support for a cell didn't mark the stellation as no longer valid, so Up and Down arrows would not necessarily cycle through only valid stellations.

Stella 1.0, 20th August 2001

• First release of Stella.