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Introduction ============ !3DEditor is a public domain package allowing the editing of 3D scenes. It is designed to be used as an editor for some of the many public domain rendering packages available. In time it may have its own renderer and movie making packages. It allows you to view your scene in a number of different ways. Each of these views is in a different window, allowing the object being edited to be viewed from many different angles. !3DEditor supports many of the standard 3D modelling techniques. Objects of rotation and extrusion can be created and manipulated, polygon matrices and meshes are supported to allow the creation of more complex objects and object separation is possible to allow complex scenes to be split up into simpler parts. The Manual ========== This manual is designed with a number of purposes in mind. It should provide the beginner with enough information to get started using the editor whilst at the same time providing the more experienced user with a reference document. It should be stressed that 3DEditor has been designed with the aim of making it as easy to use as possible, but with a program with so many different features there are always some that will be overlooked by both the novice and the expert user. The manual is available in two formats, as an Impression file and as plain text suitable for loading into Edit. The Edit copy is taken directly from the Impression version, please ignore any references to diagrams etc in this file. The Impression version should have also been included with this file. Hard copies of the Impression version may be available, please write to the address at the end of the file for details. Note that the windows and screenshots in this guide have been taken from an machine running Acorn's NewLook application, this means that some icons and buttons may look slightly different in your version. Also snapshots have been taken in high resolution mode, some 3DEditor icons are slightly different for lower resolution modes. An Introduction to 3D ===================== This section should serve as an introduction to some of the terms used in the rest of the manual. (Note that I have taken some liberties with the "correct use" of some of the terms) Co-ordinate Systems ------------------- There are two prevalent coordinate systems in 3D graphics, the left hand and the right hand system. 3DEditor uses a right hand system with the positive Z-axis going into the screen. This system is similar to that used by many rendering and raytracing programs, but differs from that used by some CAD packages, 3DEditor's export facility will convert the coordinate system when exporting to any programs using a left-handed system. Primitives ---------- The 'Primitives' are the basic elements that make up a scene. 3DEditors most simple primitive, the one from which all other items are made, is the four sided plane patch. Technically speaking a plane is a shape of infinite size, so 3DEditor is only using a small section of this, or a patch. However, the term plane is used throughout this document to mean a four-sided planar patch. "Planar" means that the item is "flat": imagine a rigid metal sheet. The sheet can lie in any direction in space, but is always planar as it has no bends in it. Many rendering packages allow circular or spherical objects to be created by using Quadric functions. 3DEditor does not support this at present as it was felt that the usefulness of these objects was severely limited. Complex shapes are simpler to define as combinations of planes and most renderers allow planes to be 'smoothed' so they appear to be a curved surface. Coupled with the large number of calculations required to generate mathematically defined surfaces and the difficulty in defining them in the first place, it was decided to omit these from the editor. The next step up from the plane is the mesh and the matrix. A mesh is an unstructured selection of planes, whereas matrices are ordered into rows and columns. Matrices are most useful as an internal construct, meshes are far easier to create irregular shapes with. Using the Editor ================ This section of the manual will describe the basic techniques required to use the editor. Loading the Editor ------------------ 3DEditor is loaded in the standard RISC OS manner - by double clicking on its icon. A screen will appear to show that loading is proceeding correctly. Providing there is enough free memory in your computer (the full editor needs around 700k) the screen will disappear leaving the 3DEditor icon on your icon bar. Clicking on this icon will open the main editor window. Note that at present only one file can be edited at a time. Clicking again on the icon will produce an error, and attempting to load a new file whilst a file is still being edited will start up a new copy of the editor (if you have enough memory). The Editor Windows ------------------ After clicking on the 3D Editor icon the following windows should be displayed : The display is made up of three windows. One of these, the toolbox is constant for all tools. It provides a means of selecting the current tool (by clicking on its icon) and of exiting tools such as sweep and extrude that take over the main display window. The main display window is the white window, in the centre of the display. Up to twenty of these windows can be open at any one time, but only one window can be "active". The active window is shown by a yellow title bar, and is the window to which the tool and info boxes will be attached. Any hot-key presses (see later) will have effect in this window The information box is the most complex of all of the windows as it changes for every tool. However the right hand section of the box remains constant for most tools and provides a number of important functions. The Information Box ------------------- The information (or info) box shows settings and options related to the current tool, however some parts of the info box are constant for all or most tools : Grid Controls These buttons provide a means of controlling the grid. The button to the left turns the grid on and off and the button to the right locks the cursor on and off the grid. The grid is discussed in detail in a later section Point Clipboard This is a very useful tool when editing a large image. Clicking on the "into" clipboard button (to the left) will store the coordinates of the currently selected point or item. Clicking on the button to the right (the "out of" clipboard button) will move the current point to the last stored point. In this way large numbers of points or objects can be moved into position without having to remember detailed coordinates. This clipboard is completely separate from the object clipboard discussed later in this document. Step Sizes Clicking on this button will allow a set of xyz coordinates to be entered. These numbers give the amount that clicking on the compass will move the current point. Note that any raised button containing coordinates can be clicked on to alter those coordinates Compass This will be present in all 3D tools (ie not sweep and extrude). Clicking on it will move the currently selected point (usually surrounded by the black cursor) by the number of units specified by the step size, in the direction of the arrow clicked. Moving the box The info box can be moved by dragging the grey bar to at the far left of the box. Other sections of the info box, which change between tools will be discussed with those tools. The ToolBox ----------- The toolbox is probably the most important window in the editor, it provides a means of selecting which tool to use. All tools present will have at least one icon on the toolbox. The toolbox may look slightly different in a low resolution mode (such as 12 or 15) as the sprites have been redefined. Each of these tools will be described in a section later in the manual. However, a few things must be noted about the toolbox : • The tool currently in use is the one highlighted in orange, in the toolbox shown this is the selector. • It is possible to re-order the icons in the toolbox. To do so drag the tool with the adjust button of the mouse to its new position. If you choose to "Save Choices" (see later) the new icon arrangement will be saved. • The toolbox's position can be moved in relation to the infobox by dragging the dark grey bar at the top of the window. • The width of the toolbox can be altered, see the "Customising" section later in the manual. Menus and Keys -------------- 3DEditor has two separate menu structures : the icon bar menu and the main menu. These are accessed by clicking the middle button over the iconbar icon and one of the main windows respectively. The behaviour of individual menu items will be discussed later, however some points apply to all menu items. • Display options chosen from the menu affect the window form which the menu was opened, not the currently selected window. • Items which are shaded are not usable, usually because the current selection does not allow that operation to be performed on it. • The letters shown to the right of the menu option are the "hotkeys" which allow the menu operation to be carried out from the keyboard. A standard syntax has been adopted through out the RISC OS desktop. • Menu items will be given in a standard form : ie View -> Display Type -> Perspective means to select the View submenu, then from that the Display Type sub menu and from that the Perspective option. Moving Points ------------- 3DEditor supports 3 different methods of moving points or objects. Not all methods are used by all tools, but those not supported will be noted in the tool description. The first, and most intuitive method is by dragging points around the screen. this is done in the usual RISC OS fashion by clicking on a point then holding down the mouse button whilst moving the mouse. This method has a number of drawbacks, mainly to do with the fact that the mouse can only work in 2 dimensions. In all situations the third coordinate that is not displayed (ie the Z coordinate in an XY view, or the Y coordinate in the XZ view) will remain constant. In rotated perspective views, the program tries its hardest to work out the correct positioning of the point, but errors can creep in. The second, more reliable method is by using the compass as described above. The mouse can still be used to select which point or object is to be moved by clicking on the point. This method gives more accurate positioning than dragging. The third method, perhaps the least intuitive, is to type in coordinates. Every point in the item being edited will have a raised box, similar to the step size box, associated with it. Clicking on this box will bring up a point entry window allow X,Y and Z coordinates for the point to be entered. The Clipboard ------------- This is an area of memory in which items in the scene can be temporarily stored, items can be : • cut (menu: Select->Cut, key CTRL-X) or • copied (menu: Select -> Copy, key CTRL-C) to the clipboard and subsequently • pasted (menu: Select -> Paste, key CTRL-V) back in to the scene. These operations work on the currently selected item, or items and return control to the selector tool once they have finished. Copying just makes a copy of the item, cutting removes it from the scene altogether. Pasting puts the contents of the clipboard into the scene 100 units up, left and back from their original position. It should be noted that the clipboard can only store one set of items, cutting or copying another set will clear the clipboard. Cutting and pasting and related operations are discussed in more detail in the "Item Manipulation" section below. Viewing Your Document ===================== This section of the manual will describe the different types of display available, how to zoom into your scene and how to control the grid. It also describes how to put colours on the display and how to preview the scene. Projections and types of display -------------------------------- Different types of display can be selected from the View->Display Type submenu, each of the display types has also been given a hot-key abbreviation. Perspective is the display type used by all renderers and raytracers and is comes the closest to modelling real objects. However, it is the hardest tool to edit images in. An XY view is a "front" view and is obtained by simply ignoring the Z coordinate. A YZ view is a "side" view, also referred to as an elevation. An XZ view is an overhead view, commonly called a "plan view" Isometric is the kind of 3D view most commonly found in technical drawing. It is perhaps the best view for viewing the shape of a 3D object. Multiple Views -------------- It is often useful to have more than one view of the scene you are editing, in fact it is probably easiest (if you have enough memory and a large enough monitor) to have four views open - these being XY, XZ, YZ and perspective. In order to open a new view of the scene select the View->New View option (key: F4). This will open another, perspective view of the scene. To change this to another view type, just click menu over the window and select the new display type as detailed above. To change between views, just click on the main screen of the view you wish to change to. The tool and infobox will then snap to the new view, and the title bar will change colour to yellow. The current view always has a yellow title bar. Changing the viewing angle -------------------------- It is possible to change the angle from which the perspective viewer views the scene. It is this viewer angle that is used by all of the exporters to place the observer for ray tracing. The angle is set using the viewer tool. Clicking on the viewer tool will bring up an info box containing one coordinate block. This block contains the X and Y rotation and the Z distance for the perspective viewer. These values can be altered either using the compass or by the coordinate entry window accessed by clicking on the coordinate block. Distance values which place the observer inside the scene should be avoided, as they can cause errors and strange displays. Only one set of values for the perspective viewer are available so if more than one perspective viewer is open they must all look in the same direction. Note that this tool can be accessed whilst no perspective viewer is in use, it just has no effect other than to force a redraw of the display. Changing the viewing zoom ------------------------- It is often useful to be able to look closely at a particular area of the scene you are drawing. The scale tool allows you to zoom in and out of the image using a number of different methods. Clicking on the scale tool icon will bring up an infobox similar to that shown below : Clicking on the "zoomed to" button (showing 100% in the picture above), will allow you to alter the zoom by selecting values from a dialogue box. The compass and the second raised box allow you to move the centre of the screen around, like moving a slide around under microscope. The simplest way of zooming however, is to click on the display window. Clicking with select will zoom in to the pointer under the lens pointer, clicking with adjust will zoom out. Changing the grid size ---------------------- As noted above, display of and locking to the grid can be controlled using buttons on the info bar. However, it is also possible to change the size of the grid. Choosing View->Grid (or CTRL-F10) will open the grid control dialogue box. This allows the X, Y and Z size of the grid to be specified. The size is given by the system coordinates used elsewhere in the editor, and gives the space between points on the grid. Note that whilst only 2 dimensions of the grid are displayed, the third dimension is locked to when lock to grid is enabled. Display of Colours ------------------ When an image is nearing completion and colours have been given to all of the items, it is useful to be able to see at a glance which colours have been assigned to which items. Selecting View -> Show Colours or pressing F6 turns on a coloured version of the display. It colours the lines of items with the nearest possible approximation to their actual colour, as a result it works best in 256 colour modes, and some of the colours show in 16 colour modes may be different from the actual colours of the items. Selecting an item will temporarily re-colour it to black, so items which "disappear" can still be edited. When "Show Colours" is enabled a tick will appear next to the menu item. Selecting it again will disable to display of colours. Note : It is possible to change the background colour from white to black - see the Choices section for more details. This allows white coloured objects to be visible in a coloured display. Depth Fading ------------ As scenes become more and more complicated it can become very difficult to tell which items are in front of each other. Depth Fading fades items out as they move further away from the viewer, so making it easier to see the order in which they come in the scene. Clicking on View-> Depth Fade will open the depth fade dialogue box. Start at gives the Z coordinate at which depth fading is to start. Any items in front of this in the scene will not be faded. Step size gives the size of the step between each change of intensity. As only 7 grey levels are available, any items more than 7 times this away from the start position will not be shown. The Use depth faded display option must be enabled for depth fading to be used. Note also the depth fading will not be used if Show Colours is enabled. Displaying Nodes ---------------- Nodes are the small red dots displayed on the editable points of every item when selected. Sweeps and extrudes, by default only have the points which were entered by the user highlighted with nodes, the calculated points do not have nodes displayed on them. It is possible to force the system to show all of the nodes (both editable and calculated) in the display by selecting View -> Show all nodes (key : F5). When enabled a tick will be displayed beside the option. Selecting the option again will disabled it. Previewing the Image -------------------- Selecting View -> Preview will start the previewer. This displays an example of what your scene will look like once rendered. Once the previewer has been selected an hourglass will appear. This hourglass will stay on screen for some time as the previewer calculates how to correctly display the scene. The screen will then clear and the previewer will display the correctly shaded version of your image, using whatever colours, lights and observer you have defined. Once the previewer has finished pressing any key, or clicking on the mouse will return to the desktop. The previewer uses a perspective transformation with the viewer located in the same place as the standard perspective viewer (see above). Locating the viewer inside the scene may produce unexpected results. If any light sources have been created then the previewer will shade the scene as if this light source is located at infinity (ie defined as a parallel beam - see the Light & Colour section for details), if there are no light sources then the scene will be displayed with every item fully lit. The previewer will only shade correctly scenes containing one light source. If more than one light source exists then the previewer will display a warning then ignore all except the first light source that is defined, in effect treating it as a single light source scene. Previewing is performed in a mode 15 screen, separate from the desktop. If the system is very low in memory, and the current screen mode is smaller than mode 15 then the previewer may not function correctly. It is not at present possible to save the images produced by the previewer. Note that the previewer can take some time to complete the preview, and takes over the desktop whilst doing so. It is not currently possible to interrupt the previewer whilst it is in operation, but even the largest of scenes should take no less than 10 minutes to preview. Filing ====== This section explains the numerous ways of loading, saving, merging and exporting 3DEditor files. It should apply to all Risc Os filing systems. Loading a file -------------- All 3DEditor files should have the same, standard icon. To load one of these files it is necessary for the filer to have "seen" the 3DEditor application, this is achieved by opening the directory viewer - for more information see the Acorn manuals supplied with your machine. Once the application has been seen the file can be loaded by either double clicking on its icon, or by dragging it to the iconbar 3DEditor icon, if 3DEditor is already loaded. 3DEditor can only edit one file at a time, attempting to load another file whilst still editing one will load another copy of the application (if you double clicked on the icon) or produce a warning (if you dragged the file to the iconbar). Merging a file -------------- A file can be merged, or combined with, an existing file by dragging the file to the 3DEditor main window in which the existing file is being edited. At first nothing will appear to have happened, however all of the objects and colours (see later sections) from the file will have been added to the list of objects and colours of the existing file. Saving a file ------------- Selecting File->Save or pressing F3 will open a standard Risc os save box. The file icon in this box can then be dragged to a directory viewer or a filename entered in the box below and OK clicked, to save the file. This is the standard Risc Os save technique, and more details can be found in Acorn's documentation for your machine. Exporting a file ---------------- The main reason for 3DEditors existence is to export files to other renderers. At present 2 renderers and !Draw are supported for output. In order to export chose the appropriate option from the File ->Export submenu, then save the file (or directory) in the manner described above. BAU Renderer The BAU renderer was provided on their June 1993 cover disc. It is a renderer, as opposed to a raytracer and as a result supports few of the options for reflection etc. It is however fairly fast to output (hours rather than days). Several problems still exist with this exporter. The observer and light sources are not positioned correctly, and must be altered by hand in the finished file. In addition, the renderer appears to be unable to handle certain positions of planes, particularly those which intersect each other. Draw The draw exporter is different from all of the others in that it outputs 2D rather than 3D data. It produces a file which can be loaded by Acorns !Draw utility. The file produced is of the view on the currently selected display, it does not always produce perspective views, so making it useful for high resolution screenshots etc. The display produced can be somewhat small and is ungrouped, however scaling in Draw can solve this. Artworks seems to have a problem with reading in draw files produced by the editor, however loading the file into Draw, then resaving it seems to cure the problem. QRT Perhaps the first "true" PD raytracer available for the Arc, QRT is now starting to show its age. However it is still capable of producing high quality images, albeit in quite a long time. The QRT exporter can cope with the full range of current object and colour options, however QRT seems to object to files containing a large number of items, usually by producing a "malloc" error. This can arise especially in files containing a large number of swept items, or swept items with many sides. Global parameters for QRT can be altered from the "Choices" option - see the "Choices and Customising" section. Creating Primitives =================== As mentioned earlier the primitives are the basic building blocks of the scene. This section covers matrices and planes. Meshes - a construct created by linking planes together are dealt with in a later section. Planes ------ Planes are created with the plane tool. Clicking on this tool with nothing selected will create a new plane, clicking with a plane already selected will allow you to edit that plane. The standard plane, which is created whenever nothing is selected has corners (0,0,0), (0,100,0), (0,100,100), (100,0,0) and as a result will only appear "square" in an XY view or a perspective view with the observer located at the origin, in other views it is likely that it will appear as either a vertical or horizontal line. The current coordinates of the plane are shown in the plane infobox: Points on the plane are selected by either clicking on them, or by clicking on the radio button next to their co-ordinate block. Once a point has been selected it can be moved by using the compass to the right of the infobox. Points can also be moved by dragging them or by entering the new coordinates by clicking on the coordinate block, as is standard for all 3D Editor tools and is detailed earlier in this manual. If a large number of planes need to be created it is possible to create them one after another, without having to leave the tool by clicking on the "new plane" icon in the centre of the infobox. Clicking on this will create a new plane at the standard plane coordinates. Planes are different from other item types in that moving them (see the Item Manipulation section) directly affects the coordinates shown in the infobox. Whereas all other objects take the movement as being an offset to their existing coordinates, planes apply it immediately to the coordinates. This is for simplicity when editing, moving and rotating a large number of planes. Matrices -------- A "matrix" in 3DEditor terms is a collection of four sided shapes arranged in rows and columns. It can be thought of an ordered combination of planes, where every plane (except those on the edges) has 4 other planes next to it. In 2 dimensions it can be thought of as a grid, as the icon shows. As with the plane tool the matrix tool reacts differently depend upon whether a matrix is currently selected. If a matrix is currently selected then it assumes that you wish to edit it, otherwise you will be prompted with a dialogue box and asked to create a new matrix. Creating a new matrix You will be prompted by the following dialogue box: The X gives the number of planes in the matrix in the X direction, the Y the number of boxes in the Y direction. Note that all matrices presume that they are lying in the XY plane, no matter which plane they actually lie in. Entering 0, or a negative value for either direction will give an error. If you have selected the matrix tool by mistake then clicking on cancel will return you to the selector tool, otherwise clicking on OK will cause a short wait whilst the matrix is calculated, then allow you to edit the matrix Editing a matrix This is the mode the tool will start in if you click on it with a matrix selected or after creating a new matrix. An info box similar to that shown below will be created : Current Point gives the X,Y and Z coordinates of the currently selected point (the node surrounded by the cursor on the display). Clicking on this button allows the coordinates of the point to be altered in the usual manner. Coordinates can also be altered with the compass or by dragging. The second part of the infobox allows the point being edited to be altered. As mentioned earlier points are arranged in an XY grid, so a point can be specified by a XY coordinate. Clicking on the box in the centre allows this coordinate to be entered directly, clicking on the buttons around it allow the selected point to changed in that direction. The selected point can also be altered by clicking on the display on the point. In a large matrix, it may be difficult to select some points on some views in this manner, this is where the process outlined above can be useful. Note that a matrix coordinate of (0,0,0) is not necessarily at the scene origin as any movement etc, is applied later. This is to allow complex objects to be built up. Item Selection and Transformation ================================= This section covers methods of selecting items and rotating, scaling and moving them. It includes details of how to change item's types and also deals with how to apply the transformations permanently. It goes into more detail in the operation of the clipboard and other methods of cutting, copying and pasting. Selecting Items --------------- The selector is probably the most used tool in the editor. It allows the user to select any item or combination of items in the current object or scene. As mentioned before, selected items are highlighted by the inclusion of red "nodes" on each of their editable points, displaying clearly exactly which items are selected. Items must be selected before they can have any other operation performed upon them. For this reason, a shortcut has been provided for entering the selector tool: Pressing TAB will toggle from the current tool into the selector tool for as long as TAB is held down, when TAB is released control will return to the original tool, provided no major changes have taken place. This shortcut is supported by most tools which work with the standard display. Tools which use a different display (Sweep and Extrude) do not support this. Selecting The selector can be used to select items in a number of different ways : If you want to just select one item it can be selected by : • Clicking on the item with Select. Where more than one item is in the same place, repeatedly clicking will advance through the items in the reverse order that they were created. • Using the selector arrows. In the centre of the infobox there is a small box with two arrows either side of it. Repeatedly clicking on either of these arrows will cycle the selection through the items. • Dragging a box around it. By clicking on a part of the display containing no items and dragging the mouse a dotted box will be displayed. To select the item drag the box out until it encloses all of the item then release the mouse button. Note that in complex scenes this is very likely to select more than one item. If you want to select several items you can : • Click adjust on an unselected item to add it to the selected items. (Clicking adjust on an already selected item will remove it from the list) • Drag a box around all of the items you wish to select. Only items which are fully enclosed in the box will be selected. If you want to select all of the items in the scene : • Choose Select->Select All or press CTRL-A Unselecting This can also be done in several different ways: If you want to unselect all of the items in the scene: • Click select on a part of the display containing no items If you want to unselect one item out of many • Click adjust over the item to be unselected Moving Items ------------ The selector tool is also used to move items around the display. When the selector tool is started it will provide an infobox : The line Moving a Plane will change to give details about whatever item is currently selected. The Currently at box shows the current coordinates of the item and can be clicked upon to alter these values. The item, or selection of items can also be moved by dragging and by using the compass. At present, when moving a selection of items Currently At shows their displacement from their current position. This will alter in the next version. Note also that point coordinates can be used from this tool. Rotating Items -------------- Items can be rotated in the X, Y and Z direction by using the rotator tool. This tool works in basically the same way as moving an item, except that the item cannot be dragged. It is important to note that the X,Y and Z rotation are directions, not axes: Rotating in the X direction moves the object in that direction, and is equivalent to rotating about the Y axis. The equivalents are : X direction : Y axis Y direction : X axis Z direction : Z axis Note that this is a purely historical difference, it is likely that later version will be able to work in either format with an option to change between them. Scaling ------- Scaling along the X, Y and Z axis is provided by the scale tool. Again, scaling of items works in roughly the same way as moving except that the coordinate window is the only recommended entry point for scales as the compass produces very large scaling steps, and is difficult to control even at small step sizes. Applying the transformations ---------------------------- The data regarding rotating, scaling and transformation is held separately from the coordinates that make up each item. This means very little error is introduced whilst altering each of these, but can cause difficulties, especially when carrying out multiple rotations and transformations. For this reason the "apply" feature was made available. This permanently applies the moving, rotating and scaling transformations to each of the coordinates in the item, so allow items to be rotated about points other than the origin for instance and allowing multiple transformations to be easily performed. Applying transformations to large objects can also speed up redraw as it reduces the amount of work required. Apply is used by selecting the items you wish to carry the operation out on then choosing Items -> Apply. It is recommended that once an item is in the correct position and especially if further transformations of the object are likely that apply is used. Some newer tools will carry out an apply automatically before doing further transformations. Fitting an item into a space ---------------------------- The Fit-to tool is designed for those situations where an item must be rotated, scaled and moved to fit exactly in a given space. Calculating the required rotations and scaling by hand can be very time consuming, this tool has been designed to do this itself. The fit-to tool can only fit single items and cannot fit objects. You will be unable to select the tool if your current selection is not appropriate. On selecting the tool the screen display will change to show your selected item greyed out, and a copy of your selected item to one side. The display will also show two lines (these will be vertical in XY or straight on perspective views). The first of these lines (to left normally) is the source line, the second (to the right normally) is the destination line. How it Works The module carries out a transformation so that the points lying under the source line lie under the destination line in the same positions and so that all other points are rearranged in the same way. In other words, you specify a line along the original shape and the way the line should lie and a transformation is performed so that the whole shape is lies in the same place relative to the line. It is perhaps best explained by an example. Given a cylinder, with the source line lying along its centre, the cylinder would be rotated and scaled so that the destination line also lies along its centre no matter where the destination line is. An example series of pictures is given at the side. The best way to find out how this tool works though is to play with it. Using the tool Having clicked on the tool icon the display will change as noted above and the infobox will, as usual change: The source / destination selector controls whether you are editing a point on the source or on the destination line. Point 1 / Point 2 controls which point on the line the compass affects. As normal points can be selected by clicking on them and moved by dragging and entering coordinates as well as by using the compass. The selected point is always shown by the cursor. After any movement of point there will be a short pause whilst the module calculates the new transformation for the shape. When you exit the tool, the grey source shape will disappear and the destination shape will be left. This tool will also apply any existing transformations before calculating its own. Mirroring Items --------------- Mirroring can be carried out by scaling an item by a negative number. To make this process easier three menu options have been added : Items->Mirror->X-axis will mirror the item about the X-axis Items->Mirror->Y-axis will mirror the item about the Y-axis Items->Mirror->Z-axis will mirror the item about the Z-axis Note that these transformations simply scale by the negative of the existing scale, and as a result will need applying if further, more complicated transformations are required. Changing Item Type ------------------ The type of an item can be changed along the following path : Sweep / Extrude -> Matrix -> Mesh Note that a loss of information occurs for each step to the right, as a result the process is irreversible and the items can no longer be edited by their old type editor (ie Sweeps can no longer be edited in the sweep module) The options listed below will only be available if a single item of the correct type is selected, Two menu options, with hotkeys are provided : Items->Convert to Matrix (key CTRL-N) Items->Convert to Mesh (key CTRL-M) Deleting an Item ---------------- The selected items can be deleted in two ways : • By choosing Select -> Cut (key CTRL-X) : This is the safest method as the item is copied to a clipboard then deleted so it can be replaced by pasting, • By choosing Select -> Delete (key DELETE) : This deletes the item completely - leaving the clipboard intact. There is no way of recovering an item deleted in this manner, so use with care. Copying an Item --------------- Items are copied by copying them to the clipboard, then by pasting them back into the scene. This was described in the "Clipboard" section in the "Using 3DEditor" chapter. Note that pasting does not clear the clipboard so many pastes of the same item can be carried out Clearing the Clipboard ---------------------- If a very large item is copied then pasted, it can be annoying to have a large amount of memory taken up by the clipboard. For this reason a "clear clipboard" command is provided. Using Select->Clear or CTRL-Z will empty the clipboard and may free some memory. Note that this will not necessarily be reflected by making more memory available to the Wimp or to other applications. Item Deformations ================= This section is different from the previous section on transformations in that the tools described here actually change the physical shape of the item being edited. This brings a problem which is common to all these tools - if you deform a shape, then the planes making up the image can become too distorted to be renderable. The solution to this is an intelligent splitting algorithm, which has not yet been included. As a simple precaution only twist or bend items in directions in which there are a large number of planes to absorb the impact (or only twist / bend by small amounts). Tapering -------- This is the simplest of the deformations available in that it just decreases the size of an object as it moves along a particular axis, producing shapes similar to that shown on the right, below. Tapering repeatedly, by small amounts can introduce very interesting curves into the shape. Note that as tapering is a linear transformation it does not distort shapes in the same way as the other deformations Taper will only work with single item selections, and objects and lamps cannot be tapered. Tapering will automatically apply any existing transformations to the shape before starting. Providing the selected item is suitable for tapering, clicking on the taper tool will change the infobox to : It will also display a line on the screen. This is axis about which the tapering will take place. The axis can be altered by either entering coordinates by clicking on the Taper along box or by using the compass. Dragging will not work. Due to the way in which the calculation is performed only alterations of the Y and Z rotations will have any effect. The rotation in this case is about the Y and Z axis, not in the Y and Z direction. Scale by gives the amount which the item will be shrunk every 100 units along the axis. They are given as X and Y coordinates, as if the axis of rotation was the Z coordinate. Once all of the values have been set up satisfactorily clicking on Go will taper the selected item. Twisting -------- Twisting can be produce some startling effects. It progressively twists an item as it goes further along a specified axis and can be used to create many different types of shape. When the twist tool is selected the infobox will change : As with the taper tool Twist about gives the axis along which the deformation is to take place. This axis can be altered by entering Y and Z coordinates into the coordinate box, or by using the compass. Rotating by gives the number of degrees the item is twisted clockwise every 100 units. Once the values are set up correctly clicking on Go will twist the item. Due to the permanent nature of twists it is best to twist by small increments until the shape looks correct. Due to the fact that twisting is a non linear operation it is possible to deform the items so much that they will no longer correctly render. Things to look out for include planes which cross themselves and planes with large "bends" in the middle - so that they are no longer planar. Constructs of Primitives ======================== This section describes items which are made by combining the primitives together using the "Join Items" command. At present only one such item type is available - the mesh Joining Items into a Mesh ------------------------- A number of planes can be joined together to produce a new item called a mesh. This preserves all of the original data present in the plane definition, but compacts it into a neater and more editable form. To create a new mesh, just select a number of planes (2 or more) and select Items -> Join Items or CTRL-I. To add planes to an existing mesh, carry out the same procedure except include the mesh in your selection as well. Providing that your selection contains no unjoinable items the selected items will be removed and replaced by a single, identical mesh. If items that cannot be joined are present, a warning message will be given and no changes will be made. Splitting a mesh into planes ---------------------------- If you wish to combine two meshes together, then one must first be split into planes. To do this select the mesh to split and choose Items -> Split Items or press CTRL-L . This will split the mesh into the planes which originally made it. This option can also be useful when a mesh grows too large to be manageable in the editor, as it is possible to then split it into two separate meshes Editing a mesh -------------- Clicking on the mesh tool, with one single mesh selected will allow you to edit that mesh. Providing your selection does not contain any other items, the mesh tool will display its infobox As usual Currently at gives the coordinates of the current point, and can be altered by clicking on the coordinate box, by dragging or by using the compass. The box in the middle of the info box allows the user to cycle through the points using the left and right arrows on either side of it. The current point can also be altered by clicking on the display. The miniature toolbox in the centre of the infobox contains a number of useful options New Plane The new plane button will add another plane to the mesh. This plane appears with corners at (0,0,0), (0,100,0), (100,100,0) and (100,0,0). Its corners are independent - they are not locked to any other points in the scene. Delete Plane This will remove the plane which has the currently selected point as a corner. If more than one plane shares this corner then a warning will be given and no changes will be made. The module will not let you have fewer than two planes in the mesh. If you want to return to a single plane use the split item option detailed above. Snap to Point If the currently selected point is directly over another point then clicking on "snap to point" will snap the two points together, allowing them both to be dragged and moved as if they were only one point. For snap to point to work the points must have similar X, Y and Z coordinates. Split Point This is the reverse operation to snap to point, it splits the currently selected point into however many points have been snapped to it, each of these points can then be moved independently. Tips on Mesh Creation --------------------- It is easiest to create a basic outline of your shape using the plane tool, then once this basic outline is roughly correct to join all of these shapes together into a mesh and fine tune the shape. Meshes are faster to redraw so it is best to combine any large number of planes into a mesh. Objects of Extrusion and Revolution =================================== Creating complex items can be very difficult, the two tools detailed here provide an easy method of creating certain types of shapes. Both tools require that a 2D "profile" be entered, which this then either swept or extruded to create a 3D shape. Objects of Revolution and Sweeping ---------------------------------- The sweep tool allows creation of objects of revolution. These are shapes where the user defines a profile and that profile is then moved around a circle to create a 3D item. The classic example of this technique is the wineglass or goblet. Clicking on the sweep tool will change the display to having a single line down the centre - the line about which the profile will be swept. This is a new, 2 dimensional view. It will also display a new info box. The profile for the sweep is entered by clicking points on the display. Clicking SELECT will place a new point, ADJUST will allow you to drag an already existing point to a new position. Points can only be created to the left of the centre line. Clicking on the line between two points will add another point on that line. As points are created they will be mirrored, but greyed out on the opposite side of the display. This side shows the sweep profile after 180 degrees of rotation, so the complete display can be thought of as a vertical slice through the image. Rotate through on the infobox is the number of degrees through which the profile is rotated. Using a value greater than 360, with a different Y shift can create effects such as the spiral shown on the left. The No. of faces is the number of sides the swept object will have. The more sides, the better a final image, but the slower it will be to both redraw and render. If Rotate through is increased, it is likely this number will also have to be increased, The Y shift is the increment to the y coordinate for each face. For example with a Y shift of 10 the first face would start at y=0, the second face at y=10, the third at y=20 and so on. It can be very useful to produce spirals and the like when coupled with a Rotate through greater than 360 Once everything is set up correctly clicking Go will start the sweep calculations, once complete control will return to the selector tool, with the swept item selected. If you want to edit the swept item, clicking on the sweep tool with it selected will allow you to alter any of the settings. Clicking Cancel, or on any tool in the main toolbox will abort the sweep. The sweep tool also has a miniature toolbox in the centre of its infobox. These tools provide a number of options whilst editing sweep profiles. Delete Point Clicking this button will delete the currently selected point and move the cursor back to the previous point Make Circle This will move all of the points in the profile into a semi-circle. The radius is taken as the distance that the furthest away point is from the centre of the display. This option is useful for sweeping spheres and other circular shapes. Edit Opposite Side As noted earlier the opposite side of the sweep is displayed, but cannot normally be edited. Clicking on this tool enables the editing of the opposite side. Points are moved and created in exactly the same way as for the normal side, This option can be used to create some very strange shapes, as the sweep profile changes as it is rotated to join smoothly the two sides. The sweep tool also provides a grid. This is controlled in exactly the same way as the normal grid, except that the grid is 2 rather than 3 dimensional. Note that profiles can be enclosed shapes, the torus shown earlier was created by sweeping a circular shape which was offset from the sweep axis. Creating Objects of Extrusion ----------------------------- The extrude tool is the editor tool for objects of extrusion. An object of extrusion is defined by creating a cross-section, then pulling this cross-section down to create a 3D object. It is best used for cylindrical type objects which have strange cross-sections, such as the long star shown below. Clicking on the extrude tool will change the display to a 2 dimensional display containing a small cross in the centre. This cross is where the program expects the centre of your cross-section to be. As is normal, the extrude tool displays its own infobox. Points in the cross section are entered a similar way to the entry of points in the sweep module. They created by clicking SELECT, moved by dragging with ADJUST and extra points can be added between points by clicking on the joining lines. Include Top , if selected, puts a top to the extruded item Include Bottom gives the extruded item a base. Note that both of these will only work if the cross-section created is concave. Extrude depth gives the depth to which the finished item is to be extruded. For vertical extrudes (ones with Extrude angle at 0) this can easily be altered by scaling once the extrusion is complete. Extrude angle gives the angle from the vertical at which the sides of the extruded item are to slope, In this way extrude can be used to create cones, pyramids and similar items. Once the cross-section has been edited and the values are entered, the extrusion can be started by clicking on Go. Once complete this will return you to the selector tool with the extruded item selected. If you wish to edit the item further just click on the extrude tool with it selected. The extrusion editing can be cancelled by clicking on Cancel or on any other tool in the main toolbox Extrude provides a 2D grid in a similar way to the sweep tool. Control of the grid is the same as for the 3D grid mentioned earlier. The extrude module also has a small set of tools in the centre of the infobox Delete Point This will delete the currently selected point, and move the cursor on to the previously created point. Centre This moves the set of points entered so they are centred about the cross in the middle of the screen Make Circle This arranges all the points in a circle about the centre cross. The radius of the circle is calculated from the distance from the centre of the furthest away point. Lights and Colours ================== This section details the ways of entering lights and of colouring objects. Much of the information entered here will not be used by all renderers, but it is recommended that whichever renderer you intend to export to that you enter all of the available information, Creating Light Sources ---------------------- Lights sources are entered and edited using the light tool. Clicking on the light tool icon with nothing selected will create a new light source, clicking on it with a light selcected will allow you to edit that light. A light source is shown on screeen as a rectangle containing a cross. The centre of the cross is the location of the light source. When selected other lines will appear in the light source, the centre line being the direction in which the source is pointing, and if the source is a spotlight another four lines will appear showing the extent of the beam. As with all tools the light tool has its own infobox : Currently at gives the current position of the light source, clicking on the radio button next to this makes this the current point for editing with the compass and coordinates can be entered using the coordinate box. Pointing at gives the location at which the light source is pointing, clicking on the radio button will make this the current point. Clicking on Lamp Data will open a new, large dialogue box allowing the entry of many light source details. The Lamp Type options control the type of light source in use • A parallel light source, is presumed to be located at infinity and pointing in the direction given by combing the pointing at and currently at options on the infobox • A point source is located at the point in the scene given by currently at and radiates light equally in all directions. • A spotlight is located at currently at, points towards pointing at and has a beam size given by the beam angle option in this dialogue box. The colour selector allows you to enter the colour of the light source. This can be done in two ways. • Dragging each of the red, green and blue bars will change the colour shown in the beam colour box • Clicking on the beam colour box will allow red, green and blue percentages to be entered. If you are entering colour data by eye it is best to be in a 256 colour mode. The beam data area contains a number of different options related to the strength and shape of the light beam in use • The distance is the distance from the light source before the light strength starts to decrease. • The radius is used by QRT and others for calculating prenumbral shadows, • The beam angle, only available for spotlights, is the maximum angle an item can be away from pointing at to be lit Barndoors is an advanced feature which allows light to be limited to acting within a box in space. Regardless of the position of the light source, only items contained within the cube given by the 6 numbers will be lit. Barndoors are enabled and disabled by clicking the option button entitled Use barndoors on this lamp. Once a lamp has been set up satisfactorily clicking OK will store the new settings and close the Lamp data window. Clicking Cancel will restore the previous settings. Colouring Items --------------- 3DEditor creates colours by defining them in terms of names - ie Matt White and the marking items as being coloured by the colour of this name. This means that if you have a large number of items all coloured with Matt White, then change the colour of Matt White the colour of all of these items will also alter. Items are coloured by selecting them, then by selecting the colour tool. This will alter the info bar to that shown below : Clicking on the Current Colour Data box will bring up a pop-up menu. The bottom section of this menu contains a list of all of the colours currently defined. Selecting one of these colours by clicking on them will set all of the selected items to that colour. The Null Colour-None Just above the list of defined colours is the No Colour option. Selecting this will set all of the selected items to have no colour defined. This is of use for colouring items within objects (see next section) as by setting the colour of an object, any items with no colour contained in that object will be given that colour. Creating A New Colour --------------------- To create a new colour start the colour tool by clicking on its icon and select New Colour from the menu accessed by clicking on the Current Colour Data box. This will give you a brand new colour and start up the editor as described below Deleting A Colour ----------------- To delete a colour, select it from the Current Colour Data box menu, then click on the Delete colour option. Note that this does not check if the colour is currently in use, any items that were coloured with this colour will have their colour changed to None. Editing a Colour ---------------- To edit a colour select it from the Current Colour Data box and then select Edit Colour. This will open the colour editing dialogue box. This dialogue box is different to many in the editor in that there are so many options that it has to be scrollable. Clicking on the scroll bars will move through the list of options. Once the colour has been correctly edited clicking on OK will store it, clicking on Cancel will return it to its original state. Changing the colour name The colour name is changed by writing the new name inside the writable box at the top of the window. Changing the colour being edited Clicking on the arrow to the right of the writable box will give a menu of possible colours. Clicking on one of these will start editing that colour, discarding any changes made to the current colour. The colour selector All of the options which require RGB (colour) data to be entered use a standard colour selector similar to the one shown below. The RGB data set being edited is shown at the top, these are explained further below. Dragging any of the red, green or blue bars will alter the colour shown in the box to the right Clicking on the box at the right will open a window allowing colour data to be entered as red, green and blue percentages and also, for all but diffuse reflection as a percentage of diffuse reflection. Diffuse Reflection The diffuse reflection is the basic colour of the surface, ignoring any other characteristics. Many renderers base all other surface characteristics on this. Mirrored Reflection These values give how well the surface truly reflects light. This is true reflection - a perfect mirror would have red, green and blue values all at 100%. The image will look strange if mirrored reflection is not in proportion to diffuse reflection, hence the % of diffuse option on the numerical entry dialogue box. Specular Reflection This affects how metallic the surface looks. Specular reflections are the small white highlights see on many raytraced pictures. The red green and blue values give how bright the highlight is, again for realistic images these should be in proportion to those entered for diffuse reflection. The Specular Coefficient controls how sharp the highlight is, the higher the number the sharper the highlight and the more metallic the surface. Transmission This controls how much light the surface lets through as a percentage of the light falling on it. Most surfaces will have values of 0 for the red, green and blue. The Refractive index of the surface controls how much rays of light passing through the surface are bent by it. 1 is no refraction. Surface Type This selects whether the surface should be "smoothed" or whether the edges are meant to be rough. If smoothing is enabled then the corners where facets meet are rounded, so allowing polygons to represent curved surfaces. Faceted turns this off. Collecting items together ========================= It is often useful in complex scenes to be able to gather items together, so they can be used more than once without any of the problems of cutting, pasting or copying. For this reason, the object was invented. Combinations of items can be made into objects and then repeatedly placed and moved, but any alteration to the object definition will change of the placed copies. When you start editing a scene you are working inside an object. This is the root object, and is by default named Root. The object currently being edited is shown in title bar of the main window. The Object Tool --------------- Most of the possible operations on objects are carried out by the object tool. This tool allows creation, editing and alteration of objects and like all other 3DEditor tools has its own info box. However this info box, especially the two buttons in the centre will alter depending on the operation being carried out. Clicking on the arrow to the right of the Placing box will give the object box menu. When an object is being placed, it can be moved using the compass and coordinate boxes as is normal. Creating a new object --------------------- To create a new object click on the object tool then select New Object from the object box menu. Clicking on the placing box will allow you to change the object's name. Pressing RETURN in this box, or clicking on Create (bottom of the two centre buttons) will create the new object, and change the current object so you are now editing it. Editing an object ----------------- There are two ways of changing the object currently being edited. The first is to open the Object -> Edit submenu. This lists all of the objects currently defined, clicking on one of them will switch to start editing that object. The other is to use the object tool. From the object box menu select the object to be edited then click on the Edit button (bottom of the two centre buttons) which will appear. Renaming an object ------------------ To rename an object select it in the object tool as if you were going to edit it, but instead of clicking on Edit put the cursor in the Placing box and enter the new name for the object. Pressing RETURN will rename the object. Placing an object ----------------- To place an object in the display select it with the object tool in the manner described for editing but instead of clicking on Edit click on Place. A copy of the object will then appear on the display, and can be moved and resized using the tools detailed in the Transformation section, earlier. Warning: Whilst 3DEditor does its best to prevent loops appearing, it is possible to loop objects. This occurs if, for instance., Object 2 is placed in Object 1 but Object1 is placed in Object 2. This causes a large recursive loop and will give an error when display is attempted. As a result it should be avoided. Customising and Choices ======================= This section details how the behaviour of the editor can be altered to suit your own particular preferences. Selecting Choices ----------------- On the iconbar menu there are two options Choices and Save Choices. The Choices option gives access to a number of options altering the way in which the editor and its tools behave. Clicking on the choices option will give a window similar to : Clicking on System gives the system choices and QRT export gives the options for the QRT exporter System Choices -------------- The system choices provides a number of options affecting the way the entire editor functions. Toolbox width is the width in icons of the main toolbox, this can be altered to any reasonable number any tool spaces unfilled will be filled with blank tiles Show Toolbox and Show Info switch on and off the display of the toolbox and the infobox. It is likely that in later version this option will be provided from a menu. Attach Toolbox and Attach info control whether the Toolbox and Infobox are locked solid to the edge of the main window. If the option is ticked then the boxes are locked solid and cannot be moved, if it is unticked then the boxes can be moved relative to the main window. Show output colours on display performs the same action as the Show Colours menu option Show output background colour will shade the background of the display in black - useful when show colours in enabled in a scene containing white objects. Clicking Save will save the choices (see below) Cancel will ignore any alterations and OK will store the alterations, but only for this session of editing. QRT Choices ----------- The QRT exporter provides two choices, both to set some QRT variables not covered in other sections of the program. Density controls the density of items as a percentage of their transmission. Ambient controls the amount of ambient light that falls on each item as a percentage of their diffuse reflection. This means that ambient light is always taken as being white, and is forced into being at the same intensity for all items in the scene Save, Cancel and OK have the same effects as for the system choices. Saving Choices and the !Choices file ------------------------------------ Clicking Save Choices will save a note of the current Choices and also a note of the current icon positioning in the toolbox, This is saved into file inside the application directory called !Choices. This file has been designed to be human readable, and more experienced users may wish to alter the other settings contained within. Removing Modules & Tools ------------------------ If you find that there are tools and modules which you are not using then they can be removed by following the process described below. However please do not remove them without making a backup first, as 3DEditor may only be distributed with all of its files intact. To access the modules directory hold down SHIFT whilst double clicking on the !3DEditor application, a new directory viewer will open, double click on the modules directory in here. Each of the directories now displayed contains a 3DEditor module, the only vital modules are Viewer and Selector - deleting these will stop the editor from functioning. A table of which modules provide what is given below, to delete a module delete its entire directory. Module Provides Colour Colour tool and Light tool Deform Twist and taper tools Export All of the current exporters (ie BAU, Draw and QRT) Extrude Extrude tool Matrix Matrix tool, Convert to Matrix menu option. Mesh Mesh tool, Convert to Mesh, Join Items and Split Items menu options. Object Object tool, Edit submenu. Plane Plane tool Preview Preview menu option RotScale Rotate, Scale and Fit-to tools. Mirror menu option Selector Selector tool, all clipboard operations, Apply menu option. Do not delete this tool. Sweep Sweep tool Viewer Viewer tool, Zoom tool, all of the current viewers. Do not delete this tool. Hotkey Shortcuts Key With CTRL -------------------------- A Select All C Copy I Join Items L Split Items M Convert to Mesh N Convert to Matrix V Paste X Cut Z Clear Key By itself With SHIFT With CTRL ----------------------------------------------------------- Delete Delete Item -- -- F1 -- Perspective View -- F2 -- XY view -- F3 Save YZ view -- F4 New View XZ view -- F5 Show all nodes Isometric view -- F6 Show Colours -- -- F10 -- -- Grid Control Conclusion ========== Any comments on this user guide or on the 3DEditor program itself can be sent to : Simon Wilkinson 29 Kinloch Street Carnoustie DD7 7EL or emailed to sxw@dcs.ed.ac.uk New versions of the editor will be available until further notice from the above address to anyone who includes a disc, a return envelope with postage and one pound. Bugs ---- Whilst I attempt to ensure that versions of 3DEditor are bug free before release I do not have the time or money to carry out the extensive testing that should be performed. As I result I can make no guarantee regarding 3DEditors suitability for any particular job or any blame if 3DEditor crashes, taking with it your latest, unsaved masterpiece. The moral is, save your files regularly - 3DEditor has no undo facility (yet) so it is a good idea to save before carrying out any major alterations. I would be very grateful if anyone finding bugs in the editor could mail details of them to the above address. Copyright --------- 3DEditor is copyright 1993, 1994 Simon Wilkinson. I have granted by permission for THIS version (2.16) to be freely distributed as long as the following conditions are obeyed : • It must be distributed with all files present, and unaltered. • No charge may be made for supplying the editor other than a reasonable amount to cover costs. • The editor may not be bundled or included with any commercially sold software or product without my permission, whether or not its inclusion affects the cost of the product. • Any public domain libraries distributing the editor should get in touch with me so I can ensure their copies are kept up to date.