The Datafile PD-CD 2

home *** CD-ROM | disk | FTP | other *** search

/ The Datafile PD-CD 2 / DATAFILE_PDCD2.iso / fractals / fractal107 / fractal_10 / _fractal / help / scripts < prev

Wrap

Text File | 1993-09-21 | 12.5 KB | 297 lines

Fractal Scripts =============== The script facility allows !Fractal to be driven by command scripts rather than from the screen. This facility is provided to allow: a) Batch running, useful for functions that take a long time to plot. Multiple plots are allowed and the images can be saved. b) Creating composite fractals, such as Fault shapes or multiple L-systems. c) Creating a fractal followed by 1 or more 3d transforms. Essentially the script language simulates accessing !Fractal from its menus and panels, so you get full access to its functionality. Scripts are text files created in !Edit or any other editor. They feature simple expression evaluation, variables and screen plotting. They provide a means for creating complex images from multiple fractals. Several scripts are provided in the Resources directory (use Misc->Resources from the menu to open), and should help to illustrate the syntax and capabilities. Running Scripts =============== Scripts are run by dragging the file onto a !Fractal window or its iconbar icon. Scripts will normally specify the fractal function they require. A script may be terminated by clicking Adjust. Any error messages (syntax or otherwise) are written to the file ScriptLog in the Resources directory. To syntax check a long script just comment out all the Draw commands and run it. Sprite images are very large, so to perform a long run saving the images as you go, save the images in GIF format or use an ArcFS or Compression pathname, since sprites compress very well. This should allow 20+ Mode 15 images per 800k floppy. To superimpose fractal images use the command:- Off Image,Redraw,Clear For images plotted using the x/y pixel mapping, X/Y Guessing must also be turned off unless the x/y image is plotted first. This is because the guessing algorithm looks at the colours already plotted to see if subsequent pixels need plotting. Script Syntax ============= Essentially the syntax is free format with punctuation necessary only to avoid ambiguity. The first line of the text must be the characters "Script". Follow these syntax guidelines: a) Multiple commands are allowed on the same line, except for comments where the rest of the line is ignored. Use a semi-colon (;) to separate each command. b) Case of commands and variables is not significant. c) Commands and keywords may be truncated to the most significant characters. Variable names must be given in full. d) Spaces are ignored except where significant, as in menu item names and data names. e) Equals (=) may be used to seperate keywords and data values. f) Use commas (,) to seperate multiple items for a command (eg. Data or Select). Command Summary =============== Note: Refer to the main help files for permissable values for data items. Square breakets [] indicate optional items, a vertical bar | is a choice between values, exp an expression (explained later) and str_exp a string expression. \ Comment All text until end of line is ignored. 3d_Elevation exp Sets the 3d elevation to angle in degrees. 3d_InvLog Sets the 3d Inverse Log mapping. 3d_Log Sets the 3d Log mapping. 3d_Linear Sets the 3d Linear mapping. 3d_Max exp Sets the 3d maximum height value. 3d_Min exp Sets the 3d minimum height value. 3d_Riemann On | Off Sets the 3d Riemann Plot on or off. 3d_Rotation exp Sets the 3d rotation to angle in degrees. 3d_Scalar exp Sets the 3d height mapping scalar. 3d_XY_Plot On | Off Sets the 3d X/Y Plot on or off. CellFill exp,exp Invokes the CellFill function starting at x/y. Clear Clears the image. Colour exp1 [,exp2] Like GCOL except sets the physical colour. Draw Plot the current function. Data item=exp [,...] Set one or more data items, name as in data panel. Fractal=function name Set fractal function. Gcol exp1 [,exp2] Similar to the BASIC GCOL statement. If / Else / Endif Script control - see later. Load str_exp Load a sprite or resource file, but not a script. Off item1,item2,... As Select, but sets menu item off if on. On item1,item2,... As Select, but sets menu item on if off. Pal_Blue exp1,exp2 Sets the level of the blue component for a colour number. Pal_Green exp1,exp2 Sets the level of the green component for a colour number. Pal_Red exp1,exp2 Sets the level of the red component for a colour number. Plot exp,exp,exp Similar to the BASIC PLOT statement. Plot_Change exp Sets the colour change interval for point plots. Plot_Colour exp Sets the physical colour for point plots. Plot_Random On | Off Random colouring on/off for point plots. Plot_Step On | Off Step colouring on/off for point plots. Plot_Stepby exp Sets the step colour increment. Plot_Type exp Sets the point plot style. Select item1,item2,.. Select menu item where item is name as in menu. Save_AFG=str_exp Save image in AFG format. str_exp is filename. Save_Image=str_exp Save image. The full pathname should be given, unless you set the current directory beforehand. var = exp Set a variable to the value of exp. While / Endwhile Script control - see later. XY_Guessing On | Off Sets the X/Y Guessing on or off. Turn off to allow x/y plot images to be superimposed. Command Details =============== CELLFILL exp1, exp2 exp1=x coord, exp2=y coord (in os units) -------- This invokes the CellFill function starting at the given coordinates. All adjacent pixels of the same colour as the start point will be set to the CellFill colours. This allows you to flood-fill areas previously plotted. To set the fill colours switch to the CellFill function, ie. Fractal=CellFill \ Selects CellFill Data Up=45,Down=56 \ Set the colours Fill x,y \ Start filling at x/y The standard cellfill function can be invoked via DRAW. See MandyGold2 and MandyGold1 scripts for the different effects between the two styles of filling. COLOUR exp1 [,exp2] ------ Sets the graphics colour in a similar way to the BASIC GCOL statement. If just exp1 is given exp1 is the colour, otherwise exp1 is the GCOL mode (see the BASIC manual), and exp2 the colour. Colour numbers are 0-255 and are the physical colour numbers, and thus map directly onto the current palette. This statement is for use with non-default palettes. DATA item=exp [,....] ---- Sets the data parameters for the current function, where item is the data name as shown in the Data display panel, including internal spaces. Multiple data names can be specified on the same line, separated by commas. Use Initial or InitZoom as item names to simulate these buttons on the data panel. For L-Systems the following extra keywords are available (they relate to the data panel) : Angles = exp number of angles Axiom = string expression eg. Axiom='F-F' Clear_rules clears all rules for this L-system Iterations = exp number of iterations Name = string_expression Sets name of L-system Rule = string expression eg. Rule='F=XFX' 1st letter must be the rule-id, the rule string must start in col.3 Updates (if ruleid exists) or adds a new rule. eg Data x0=34,width=n+34; GCOL exp1 [,exp2] ---- Sets the graphics colour in a similar way to the BASIC GCOL statement. If just exp1 is given exp1 is the colour, otherwise exp1 is the GCOL mode (see the BASIC manual), and exp2 the colour. Colour numbers are 0-255 and are made up of the bits BBGGRRTT where B=Blue (*64), G=Green (*16), R=Red (*4) & T=Tint bits. This format is used since it makes it easier to step through brightness levels (the BASIC format is TTBBGGRR). This mapping only works with the default palette. For other palettes use the COLOUR statement. LOAD str_exp eg. Load "<Frac$PDir>.Lyapunov" - loads a palette ---- This command allows resources such as sprites and palettes to be loaded. Use <Frac$Dir> to refer to the Fractal directory and <Frac$Pdir> to the palette directory. PAL_BLUE exp1,exp2 exp1=colour number, 0 - 255 PAL_GREEN exp1,exp2 exp2=colour level, 0 - 255. PAL_RED exp1,exp2 --------- These three commands allow the image palette to be programmed. exp1 is the physical colour number (as used in the COLOUR command for example) and exp2 is the level of colour, 255 being full intensity. To set the screen palette to the image palette, use 'Select Palette,Set Screen' - you must be in a full 256 colour mode for this to work. PLOT exp1,exp2,exp3 exp1=plot function, exp2=x-coord, exp3=y-coord ---- where coords are in OS units. This performs a standard vdu plot function with the current GCOL settings. It is provided to allow you to embellish fractal images. See your BASIC manual for plot function codes. Typical values are: 4 = Move to x/y, 5 = Draw Line to x/y, 69 = Draw point at x/y eg. PLOT 4,100,200; PLOT 5,400,300; \ Draw line from 100,200 to 400,300 See the script CIRCLES for an example. PLOT_xxx - these keywords correspond to the Plot Options panel. PLOT_CHANGE exp ----------- Sets the colour change interval for point plotting. exp is 0-999999. PLOT_COLOUR exp ----------- Sets the plotting colour for point plotting functions (Bifurcate,IFS,Popcorn etc). exp is a number from 0-255 and is the physical colour number as shown in !EditPal. PLOT_RANDOM On | Off ----------- Turns random colouring on or off. PLOT_STEP On | Off --------- Turns step colouring on or off. PLOT_STEPBY exp ----------- Sets the colour increment when stepping colours. exp is -99 to 99. PLOT_TYPE exp --------- Sets the point plotting style. exp is a string evaluating to: Overlay, OR, AND, EOR, Invert, Add, Subtract. SELECT, ON And OFF item1,item2,... ------------------ These commands simulate a menu selection, giving you access to the full facilities of !Fractal. Use Select for action options (eg. setting a display palette). Use On or Off for menu items that be switched on or off (Select would toggle between the states). The item names must be as shown in the menu structure (including internal spaces, but may be truncated) and must be seperated by commas. Use a semi-colon to denote end of command before end of line. These commands also work on panel lists (eg. L-System->List->panel) - simply code the item name in the panel as the last option, eg. Select L-System,List,Dragon ; Draw Variables And Expressions ------------------------- An expression is made up of numbers, strings, variables, operators and comparators. Parentheses are not currently supported. Numbers: standard or scientific format, eg. 43.1 or 4.31e1 Strings: enclose within matching single or double quotes, eg. "Mike" 'Mike' "Fred's" Operators: + - * / for numbers, + for strings. Comparators: = < > <> (not equal) <= >= Variables: names must begin with a non-numeric. Case is not significant. Commands are searched before variables so avoid names clashing with command verbs. Expressions are evaluated left to right, so 5+4*2=18 not 13. An expression is evaluated as a floating point number unless the first value is a string or a string expression is required, ie. 5+"41"=46 but "41"+5="415" Only 1 comparator per expression is allowed. Examples: x=45; y=x+123; z=x*y; Data item=x+4; suffix=12; Save "Image"+suffix (creates a file called Image12) IF / ELSE / ENDIF ----------------- Allows simple logic testing and control. Syntax: IF expression 1 or more statements if expression true [ ELSE 1 or more statements if expression false ] ENDIF where expression incorporates some form of comparison that evaluates to TRUE (non-zero) or FALSE (0), ie. IF x > 1. The ELSE clause is optional but ENDIF is required. IFs may be nested, each with a corresponding ENDIF. Examples: IF x=y IF x=z (because we can't say IF x=y AND x=z) statements ENDIF statements ENDIF IF x=y statements ELSE IF statements ENDIF (matches IF on ELSE) ENDIF IF name='Fred'; var=var+3; ENDIF WHILE / ENDWHILE ---------------- Allows simple loops. Syntax: WHILE expression statements ENDWHILE where expression evaluates to TRUE (statements are executed) or FALSE (skip to ENDWHILE) - see IF for the suitable expression formats. WHILEs may be nested and mixed with IF/ELSE/ENDIF.