Fractint Commands


  1. Getting Started

    To start the program, enter FRACTINT at the DOS prompt. The program displays an initial 'credits' screen. If Fractint doesn't start properly, please see Common Problems

    Hitting [Enter] gets you from the initial screen to the main menu. You can select options from the menu by moving the highlight with the cursor arrow keys and pressing [Enter], or you can enter commands directly.

    As soon as you select a video mode, Fractint begins drawing an image - the 'full' Mandelbrot set if you haven't selected another fractal type. For a quick start, after starting Fractint try one of the following:

        If you have MCGA, VGA, or better:  [F3]
        If you have EGA:                   [F9]
        If you have CGA:                   [F5]
        Otherwise, monochrome:             [F6]
    

    After the initial Mandelbrot image has been displayed, try zooming into it (see Zoom Box Commands) and color cycling (see Color Cycling Commands). Once you're comfortable with these basics, start exploring other functions from the main menu.

    Help is available from the menu and at most other points in Fractint by pressing the [F1] key.

    AT ANY TIME, you can hit a command key to select a function. You do not need to wait for a calculation to finish, nor do you have to return to the main menu.

    When entering commands, note that for the 'typewriter' keys, upper and lower case are equivalent, e.g. [B] and [b] have the same result.

    Many commands and parameters can be passed to FRACTINT as command-line arguments or read from a configuration file; see 'Command Line Parameters, Parameter Files, Batch Mode' for details.

  2. Plotting Commands

    Function keys & various combinations are used to select a video mode and redraw the screen. For a quick start try one of the following:

        If you have MCGA, VGA, or better:  [F3]
        If you have EGA:                   [F9]
        If you have CGA:                   [F5]
        Otherwise, monochrome:             [F6]
    

  3. Zoom box Commands

    Zoom Box functions can be invoked while an image is being generated or when it has been completely drawn. Zooming is supported for most fractal types, but not all.

    The general approach to using the zoom box is: Frame an area using the keys described below, then [Enter] to expand what's in the frame to fill the whole screen (zoom in); or [Ctrl] [Enter] to shrink the current image into the framed area (zoom out). With a mouse, double-click the left button to zoom in, double click the right button to zoom out.

  4. Color Cycling Commands

    Color-cycling mode is entered with the [c], [+], or [-] keys from an image, or with the [c] key from Palette-Editing mode.

    The color-cycling commands are available ONLY for VGA adapters and EGA adapters in 640x350x16 mode. You can also enter color-cycling while using a disk-video mode, to load or save a palette - other functions are not supported in disk-video.

    Note that the colors available on an EGA adapter (16 colors at a time out of a palette of 64) are limited compared to those of VGA, super-VGA, and MCGA (16 or 256 colors at a time out of a palette of 262,144). So color-cycling in general looks a LOT better in the latter modes. Also, because of the EGA palette restrictions, some commands are not available with EGA adapters.

    Color cycling applies to the color numbers selected by the 'cyclerange=' command line parameter (also changeable via the [Y] options screen and via the palette editor). By default, color numbers 1 to 255 inclusive are cycled. On some images you might want to set 'inside=0' ([X] options or command line parameter) to exclude the 'lake' from color cycling.

    When you are in color-cycling mode, you will either see the screen colors cycling, or will see a white 'overscan' border when paused, as a reminder that you are still in this mode. The keyboard commands available once you've entered color-cycling. are described below.

  5. Palette Editing Commands

    Palette-editing mode provides a number of tools for modifying the colors in an image. It can be used only with MCGA or higher adapters, and only with 16 or 256 color video modes. Many thanks to Ethan Nagel for creating the palette editor.

    Use the [E] key to enter palette-editing mode from a displayed image or from the main menu.

    When this mode is entered, an empty palette frame is displayed. You can use the cursor keys to position the frame outline, and [Pageup] and [Pagedn] to change its size. (The upper and lower limits on the size depend on the current video mode.) When the frame is positioned where you want it, hit Enter to display the current palette in the frame.

    Note that the palette frame shows R(ed) G(reen) and B(lue) values for two color registers at the top. The active color register has a solid frame, the inactive register's frame is dotted. Within the active register, the active color component is framed.

    With a video mode of 640x400 or higher, a status area appears between the two color registers. This status area shows:

          nnn  = color numbeber at the cursor location
          A    = Auto mode
          X, Y = exclusion modes
          F    = freesyle mode
          T    = stripe mode is waiting for #
    

    Using the commands described below, you can assign particular colors to the registers and manipulate them. Note that at any given time there are two colors 'X'd - these are pre-empted by the editor to display the palette frame. They can be edited but the results won't be visible. You can change which two colors are borrowed ('X'd out) by using the [v] command.

    Once the palette frame is displayed and filled in, the following commands are available:

  6. Image Save/Restore Commands

  7. Print Command

  8. Parameter Save/Restore Commands

    Parameter files can be used to save/restore all options and settings required to recreate particular images. The parameters required to describe an image require very little disk space, especially compared with saving the image itself.

  9. '3D' Commands

    See '3D' Images for details of these commands.

  10. Interrupting and Resuming

    Fractint command keys can be loosely grouped as:

    An image which is [S]aved before it completes can later be [R]estored and continued. The calculation is automatically resumed when you restore such an image.

    When a slow fractal type resumes after an interruption in the third category above, there may be a lag while nothing visible happens. This is because most cases of resume restart at the beginning of a screen line. If unsure, you can check whether calculation has resumed with the [Tab] key.

    The following fractal types cannot (currently) be resumed: plasma, 3d transformations, julibrot, and 3d orbital types like lorenz3d. To check whether resuming an image is possible, use the [Tab] key while it is calculating. It is resumable unless there is a note under the fractal type saying it is not.

    The Batch Mode section discusses how to resume in batch mode.

    To [R]estore and resume a 'formula', 'lsystem', or 'ifs' type fractal your 'formulafile', 'lfile', or 'ifsfile' must contain the required name.

  11. Orbits Window

    The [O] key turns on the Orbit mode. In this mode a cursor appears overthe fractal. A window appears showing the orbit used in the calculation of the color at the point where the cursor is. Move the cursor around the fractal using the arrow keys or the mouse and watch the orbits change. Try entering the Orbits mode with View Windows ([V]) turned on. The following keys take effect in Orbits mode.

      [c]     Circle toggle - makes little circles with radii inversely
                    proportional to the iteration. Press [c] again 
                    to toggle back to point-by-point display of orbits.
    
      [l]     Line toggle - connects orbits with lines (can use 
                    with [c])
    
      [n]     Numbers toggle - shows complex coordinates and color number of
                    the cursor on the screen. Press [n] again to 
                    turn off numbers.
    
      [p]     Enter pixel coordinates directly
    
      [h]     Hide fractal toggle. Works only if View Windows is turned on
                    and set for a small window (such as the default size.) Hides the
                    fractal, allowing the orbit to take up the whole screen. Press
                    [h] again to uncover the fractal.
    
      [s]     Saves the fractal, cursor, orbits, and numbers as they  appear
                    on the screen.
      [<] or [,]  Zoom orbits image smaller
    
      [>] or [.]  Zoom orbits image larger
    
      [z]     Restore default zoom.
    

  12. View Window

    The [V] command is used to set the view window parameters described below. These parameters can be used to:

    'Preview display'

    Set this to 'yes' to turn on view window, 'no' for full screen display. While this is 'no', the only view parameter which has any affect is 'final media aspect ratio'. When a view window is being used, all other Fractint functions continue to operate normally - you can zoom, color- cycle, and all the rest.

    'Reduction factor'

    When an explicit size is not given, this determines the view window size, as a factor of the screen size. E.g. a reduction factor of 2 makes the window 1/2 as big as the screen in both dimensions.

    'Final media aspect ratio'

    This is the height of the final image you want, divided by the width. The default is 0.75 because standard PC monitors have a height:width ratio of 3:4. E.g. set this to 2.0 for an image twice as high as it is wide. The effect of this parameter is visible only when 'preview display' is enabled.

    'Crop starting coordinates'

    This parameter affects what happens when you change the aspect ratio. If set to 'no', then when you change aspect ratio, the prior image will be squeezed or stretched to fit into the new shape. If set to 'yes', the prior image is 'cropped' to avoid squeezing or stretching.

    'Explicit size'

    Setting these to non-zero values over-rides the 'reduction factor' with explicit sizes in pixels. If only the 'x pixels' size is specified, the 'y pixels' size is calculated automatically based on x and the aspect ratio.

    More about final aspect ratio: If you want to produce a high quality hard-copy image which is say 8" high by 5" down, based on a vertical 'slice' of an existing image, you could use a procedure like the following. You'll need some method of converting a GIF image to your final media (slide or whatever) - Fractint can only do the whole job with a PostScript printer, it does not preserve aspect ratio with other printers.

  13. Video Mode Function Keys

    Fractint supports *so* many video modes that we've given up trying to reserve a keyboard combination for each of them.

    Any supported video mode can be selected by going to the 'Select Video Mode' screen (from main menu or by using [Delete]), then using the cursor up and down arrow keys and/or [PageUp] and [PageDown] keys to highlight the desired mode, then pressing [Enter].

    Up to 39 modes can be assigned to the keys F2-F10, SF1-SF10 [Shift] + [Fn]), CF1-CF10 ([Ctrl] + [Fn]), and AF1-AF10 ([Alt] + [Fn]). The modes assigned to function keys can be invoked directly by pressing the assigned key, without going to the video mode selection screen.

    30 key combinations can be reassigned: [F1] to [F10] combined with any of [Shift], [Ctrl], or [Alt]. The video modes assigned to [F2] through [F10] can not be changed - these are assigned to the most common video modes, which might be used in demonstration files or batches.

    To reassign a function key to a mode you often use, go to the 'select video mode' screen, highlight the video mode, press the keypad (gray) [+] key, then press the desired function key or key combination. The new key assignment will be remembered for future runs.

    To unassign a key (so that it doesn't invoke any video mode), highlight the mode currently selected by the key and press the keypad (gray) [-] key.

    A note about the 'select video modes' screen: the video modes which are displayed with a [B] suffix in the number of colors are modes which have no custom programming - they use the BIOS and are S-L-O-W ones.

    See 'Video Adapter Notes' for comments about particular adapters.

    See 'Disk-Video' Modes for a description of these non-display modes.

    See 'Customized Video Modes, FRACTINT.CFG' for information about adding your own video modes.

  14. Browse Commands

    The following keystrokes function while browsing an image:

    This is a 'visual directory', here is how it works... When [L] or [l] is pressed from a fractal display the current directory is searched for any saved files that are deeper zooms of the current image and their position shown on screen by a box (or crosshairs if the box would be too small). See also Browser Parameters for more on how this is done.

    One outline flashes, the selected outline can be changed by using the cursor keys. At the moment the outlines are selected in the order that they appear in your directory, so don't worry if the flashing window jumps all over the place! When enter is pressed, the selected image is loaded. In this mode a stack of the last sixteen selected filenames is maintained and the [\] or [h] key pops and loads the last image you were looking at. Using this it is possible to set up sequences of images that allow easy exploration of your favorite fractal without having to wait for recalc once the level of zoom gets too high, great for demos! (also useful for keeping track of just exactly where fract532.gif came from :-) )

    You can also use this facility to tidy up your disk: by typing UPPER CASE [D] when a file is selected the browser will delete the file for you, after making sure that you really mean it, you must reply to the 'are you sure' prompts with an UPPER CASE [Y and nothing else, otherwise the command is ignored. Just to make absolutely sure you don't accidentally wipe out the fruits of many hours of cpu time the default setting is to have the browser prompt you twice, you can disable the second prompt within the parameters screen, however, if you're feeling overconfident :-).

    To complement the Delete function there is a rename function, use the UPPER CASE [R] key for this. You need to enter the FULL new file name, no .GIF is implied.

    It is possible to save the current image along with all of the displayed boxes indicating subimages by pressing the [s] key. This exits the browse mode to save the image and the boxes become a permanent part of the image. Currently, the screen image ends up with stray dots colored after it is saved.

    Esc backs out of image selecting mode.

    The browser can now use expanded memory or extended memory. If you have more than 4 MB of expanded/extended memory available, you can use either. If you don't have 4 MB of expanded/extended memory available, use expanded memory as it will allocate as much as possible. The extended memory support will silently fail and default to the use of far memory if 4 MB of extended memory is not available.

    Here's a tip on how to zoom out beyond your starting point when browsing: Suppose you restore a fractal deeply-zoomed down in a directory of related zoomed images, and then bring up the browser. How do you zoom out? You can't use "\" because you started with the zoomed image, and there is no browser command to detect the next outer image. What you can do is exit the browser, press PgUp until the zoom box won't get any smaller, zoom out with Ctrl-Enter, and before any image starts to develop, call up the browser again, locate your zoomed image that you started with, and see if there is another image that contains it - if so, restore it with the browser.You can also use a view window [v] to load the first image, and then use the browser.

    POSSIBLE ERRORS:

    'Sorry..I can't find anything' The browser can't locate any files which match the file name mask. See Browser Parameters This is also displayed if you have less than 10K of far memory free when you run Fractint.

    'Sorry.... no more space' At the moment the browser can only cope with 450 sub images at one time. Any subsequent images are ignored, make sure that the minimum image size isn't set too small on the parameters screen.

    'Sorry .... out of memory' The browser has run out of far, expanded, or extended memory in which to store the pixels covered by the sub image boxes. Try again with the main image at lower resolution, and/or reduce the number of TSRs resident in memory when you start Fractint. Make sure you have expanded or extended memory available.

    'Sorry...it's a read only file, can't del [filename]'
    'Sorry....can't rename'
    The file which you were trying to delete or rename has the read only attribute set, you'll need to reset this with your operating system before you can get rid of it.

  15. RDS Commands

    The following keystrokes function while viewing an RDS image:

      [Enter] or [Space]   -- Toggle calibration bars on and off.
      [Ctrl-s] or [k]      -- Return to RDS Parameters Screen.
      [s]                        -- Save RDS image, then restore original.
      [c], [+], [-]  -- Color cycle RDS image.
      Other keys           -- Exit RDS mode, restore original image, and pass
                              keystroke on to main menu.
    

    For more about RDS, see Random Dot Stereograms (RDS)


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This page maintained by
Noel Giffin, TRIUMF
noel@triumf.ca