Classic Computer Magazine Archive START VOL. 3 NO. 8 / MARCH 1989

ON DISK!

SEURAT

by Sterling K. Webb


seurat1.jpg

You may think that you don't need another paint program. Well, take a look at SEURAT! It's an amazing painting, drawing, and all-around pixel-bashing program written in (are you ready?) GFA BASIC 2.0. Even if you have a library full of graphics programs, you need SEURAT. It runs in all resolutions on any ST/Mega with one megabyte of memory or more!


Look out, DEGAS Elite! Move over Cyber Paint! Now there's SEURAT--file SEURAT.ARC on your START disk.

In the beginning, there were DEGAS and NEOchrome 0.6. Then, DEGAS begat DEGAS Elite and NEOchrome 0.6 begat NEOchrome 1.0. And the graphics programs for the ST have kept on coming for three years. And now there's SEURAT, inspired by Georges Pierre Seurat (1859-1891), the French pointillist artist and "Father of the Pixel."

If you've worked with other ST graphics programs, like DEGAS Elite or NEOchrome, you'll find SEURAT's user interface very intuitive. If you haven't, you'll have fun exploring SEURAT's myriad functions. There are even a couple things you haven't seen before.


Getting Started

Because of SEURAT's size and the need for a full manual, it took a bit of doing to fit all of the files on the START disk. Before you read on, please read the sidebar accompanying this article for specific instructions on how to handle the various files. And if you're unfamiliar with un-ARCing programs, be sure to read the general Disk Instructions elsewhere in this issue.

After loading SEURAT, the title screen appears followed by the main menu from which you select the paint functions.


Diving In

Like other graphics programs, SEURAT contains the usual "primitives" - basic shapes and lines. On the left side of the main menu there is a series of function buttons. Looking down the stack of buttons on the left of the main menu, you can see that SEURAT has graphic primitives, like line, polyline (which also produces polygons), circle and disk (which can be ellipses), boxes and solids (square and round-cornered), ray drawing, plus the O-Box and O-Circle functions. There is also an area fill and a multi-function airbrush, that stipples as well as sprays.

The most basic function of a drawing program is free-hand drawing. Looking at the main menu, you'll notice that the BRUSH button is highlighted, and that the one-pixel brush box on the right side of the screen is outlined. That means you're almost ready to start drawing.

First, click on the INK button; this specifies that you want to draw with a solid color rather than a fill pattern. Now, select a color by clicking on one of the palette display boxes just above the INK button. Try a few other colors. Notice that the cursor changes color to remind you of your color selection.

You'll be using right mouse clicks to flip from the main menu to a paint screen and back again. (You can also use the Escape key.) So, let's flip over to an empty paint screen.

On the paint screen, you won't see the arrow cursor anymore, nor the brush you selected. What you will see is a big "register mark," four arms that point to a common center. Press the left mouse button and move the mouse; the brush cursor disappears and the brush paints. Release the left mouse button and the register mark cursor returns.

This "register mark" cursor is large enough to let you position even single pixels with accuracy, and, because it's xor'ed to the screen, it remains visible regardless of the color of the screen beneath it.

Before we flip back to the main menu, press the Help key. The palette display pops up on the paint screen and the arrow cursor reappears, letting you select another color. Click the right mouse button to remove the palette display from the screen and you can then resume drawing.

Assuming that you're satisfied with what you've drawn so far, press the Insert key to "fix" your work to the screen. Now, as an experiment, make one more stroke with the brush, then press the Undo key. SEURAT's Undo function will remove all work done on a screen since the last fix was done with the Insert key. Any time you want to keep your work as you progress through a drawing, simply press the Insert key.

Now, let's flip back to the main menu and look at some of those other functions.


seurat2.jpg
SEURAT lets you make a flag rippling in the breeze more
easily than Betsy Ross. The block manipulation function in
SEURAT are extensive.

SEURAT's Functions

Besides the one-pixel brush we've just doodled with, SEURAT has 35 other brushes. All 36 work in both solid (ink) colors and fill patterns. You can also have up to six simultaneous user-defined multi-colored brushes, that can be composed of any or all available colors in the palette. (These can be saved and loaded to/from disk by double-clicking on any brush box.)

Around the boundary of the Menu Screen, you'll see that SEURAT provides 92 fill patterns (46 each in color and monochrome). The selected fill pattern is shown on the left side of the screen just below the functions buttons. Double-click on the COLOR or MONO buttons and the fill editor will appear letting you modify existing fills in a variety of ways or create your own. Fills can also be stored to and loaded from disk from the fill editor.

SEURAT provides up to eight paint screens (the exact number depends on the available memory) and each screen has its own color palette. Paint screens (or just their palettes) can be copied between screens, and a palette editor allows you to alter your palette, swap colors, and load or save palettes.

SEURAT lets you carry out all graphic operations in the four write modes available on the ST overwrite, transparent, xor, or reverse transparent. Block operations can also be performed in reverse transparent, not transparent, and in any of the 16 logical combination modes of GEM, making a total of 21 block copying modes. You can also make a mask from a block and modify and copy it, also in 21 modes.

The text function allows for resizeable type in a variety of text styles in all four write modes and gives you access to the full ST 256-character ASCII set.

You can set and unset GEM's clipping function, creating (invisible) windows which put a boundary on your graphic operations. Updating and undoing the screen is totally in your control, although you can put it on automatic if you want.

Besides merely copying blocks, you can also manipulate them. They can be resized, rotated, skewed, arced to a cylindrical shape, distorted to any contour you draw, or distorted trapezoidally, even folded over or wrapped to hyperbolic sheets, if that's what you want. Blocks can also be stored to and loaded from disk.

SEURAT performs geometrical transformations on entire screens: flipping or inverting them, rotating portions of them, with four-way mirror operations and four scrolling shifts.

SEURAT can remap the color assignment of pixels over an entire screen or only over a portion of a screen, for any number of colors at once.

SEURAT has a specialized Zoomscreen that functions at 4X to 10X (20X in monochrome). The Zoomscreen has a wide variety of specialized features, including the capability to zoom a screen area in two modes: with pixels merged (solid) or separated (mosaic), as well as gridded (like electronic graphpaper) or non-gridded. On the Zoomscreen, you can draw with both right and left mouse buttons in different colors. (Very handy in monochrome!) SEURAT loads images in the original DEGAS (PI?) or NEOCHROME (.NEO) formats and saves them in DEGAS format. You can get a file directory, change drives, delete files, or format disks from within the program. SEURAT allows access to desk accessories and even maintains a logbook of which filenames were loaded into which paint screens or were last copied to other screens, in case you get lost like I do.


Button by Button: What SEURAT Can Do

The command structure of a large and complex program like SEURAT can be a little overwhelming at first, but take heart! The SEURAT.DOC file on your START disk contains a complete user's manual that explains in detail each function of the program and how to use them all. For quick reference, the following is a button-by-button list of SEURAT's many features.


Main Menu, Primary Controls


Other Main Menu Commands


Pop-up Menu


Paint Screen Commands

Note: The following applies to all paint functions unless otherwise noted.


Block Functions

Note: The mouse cursor will be the block if one has been selected or a full screen crosshair when selecting a block. If you have defined a block, be sure to use the right mouse button rather than the Escape key to flip back to the main menu.


Text Functions

Note: write mode must be selected on menu screen, not with the keyboard. Flip back to main menu with the right mouse button, not the Escape key.


seurat3.jpg
You can load, save and edit blocks, brushes, fills and pal-
ettes in SEURAT. This is the fill editor with one of the 92
included fills shown.

Fill


Ray


Line


Polyline


Box and Solid

Note: A box is an outline figure and a solid is a filled figure.


Ellipse, Circle and Disk

Note: A circle is an outline figure and a disk is a filled figure.


O-Box and O-Circle

Note: These figures erase the screen area within them as they are drawn.


Airbrush


seurat4.jpg
The zoom function is variable from 4X to 20X magnifica-
tion with a raft of well-designed features, like using the
left mouse button with one color and the right for a second.

Zoomscreen Commands

Note: The cursor arrow shows the drawing color or takes the shape of a crosshair when the cursor is off the zoom display.


Zoomscreen View Window Commands


Set Work Screen Commands


Color or Mono Fill Editor and Brush Editor


Palette Editor

Note: the cursor will have the shape of an artist's palette.


File Function Dialog

(Note: the cursor will have the shape of a floppy disk)


Block Menu

The options for the manipulation of blocks are: a) Rotate Block, b) Resize Block, c) Vertical Freeform Distort, d) Vertical Arc Distort, e) Vertical Skew Distort, f) Vertical Trapezoidal Distort, g) Horizontal Freeform Distort, h) Horizontal Arc Distort, i) Horizontal Skew Distort, j) Horizontal Trapezoidal Distort, k) All-Way Distort, l) Save Block, and m) Load Block.


Screen Transforms


Color Map

Click on SOURCE ROW color, then on DESTINATION ROW color to remap for any or all colors.

The RESET Button cancels and redraws the color map dialog box.

The WHOLE SCREEN button remaps the entire paint screen.

You may select an area to re-map by clicking and holding the left mouse button while dragging a box around the desired area.

SELECT AREA may be repeated with same settings.


Low Memory Warning

Note: A musical noise will alert you when the free memory is below 64 kbytes. To recover memory, clear the block undo stack and/or deactivate the highest paint screen.

Though I wrote SEURAT on a one drive 1040ST (never again!), running it on a Mega 4 shows that it needs about 1.2 to 1.4 megabytes of elbow-room with eight screens operational.


The End!

Whew! That should be sufficient to get you started experimenting with SEURAT's many features. Consult SEURAT.DOC for a full explanation of how each feature functions.

Sterling Webb lives and works in Bunker Hill, Illinois, a town he describes as so small that "the Rotary Club's sign 1 says 'Welcome to Bunker Hill' on both sides!" This is his first program for START.


Setting Up Your SEURAT Program Disk

SEURAT consists of seven archive files on your START disk. To set up a working program disk, you will need to follow these special instructions. If you are a new ST owner, read the sections in your Atari user's manual on how to format disks and copy files before continuing. Be sure to back up (make a working copy of) your START disk before doing anything else. There may be a file on your START disk called README.DOC; if so, double-click on it and click on Show for last minute information on SEURAT.

If you have a single-sided drive, you will need three blank, formatted disks for SEURAT. One is for the program, one is for data and the other is for the documentation; label them appropriately. If you have a double-sided drive, format a double-sided disk for all of SEURAT's files. If you have a hard drive. you may want to create a special folder for SEURAT.

Copy SEURDOCS.ARC and ARCX.TTP onto the documentation disk. Double-click on ARCX.TTP and type the filename SEURDOCS.ARC in the box that comes up on screen. Your drives LED light will come on and messages on screen will tell you which files are being un-ARCed. When the Desktop screen returns, the directory window should show the SEURAT documentation file (SEURAT.DOC), the program TYPE.PRG and its GFA BASIC ASCII listing, TYPE.LST. If these files are not on the disk, try un-ARCing SEURDOCS.ARC again; you may have misspelled the filename.

To view the documentation, double-click on TYPE.PRG and select SEURAT.DOC when the file selector box comes up on screen. This program lets you view the file. To scroll through the file, use the up and down arrow keys to move a page at a time or the right and left and arrow keys to move a line at a time. To move to the beginning of the file, Press CLR/Home; to move to the end, press the insert key. Press Undo to return to the Desktop. To print out the SEURAT documentation, double-click on SEURAT.DOC from the Desktop and then click on Print. The documentation is quite long, so be sure you have plenty of paper in your printer.


Onward

Now you're ready to create your SEURAT program disk. Copy SEURAT.ARC and ARCX.TTP onto your program disk and un-ARC SEURAT.ARC as you did the documentation. When un-ARCed, you should have SEURAT.BAS, SEURAT.INF. SEURAT.DAT and a utility program called CVERTFIL.BAS. Now delete SEURAT.ARC from your program disk; it is no longer necessary and you will need extra room on this disk. Do not delete anything from either your original START disk or your backup disk. Copy GFABASRO.ARC onto the program disk and un-ARC it.

On your SEURAT data disk create five folders, or subdirectories, for SEURAT's numerous data files. Make sure that your SEURAT data disk's window is open on the Desktop; if there is more than one window on the Desktop, click on it to make it the active window. Now select New Folder from the Desktop's File drop-down menu. Type in BRUSHES and press Return. The new folder icon will be in the directory window. Repeat the procedure to create folders called BLOCKS, COLRFILL, MONOFILL and PALETTES.

Double-click on the BRUSHES folder. This will bring up the empty BRUSHES directory window. Copy into this directory ARCX.TTP and BRUSHES.ARC. Finally, un-ARC BRUSHES.ARC as usual. This will cause the files in BRUSHES.ARC to un-ARC directly into the folder. When you are finished, delete BRUSHES.ARC and ARCX.TTP from the BRUSHES folder and click on the close box in the upper-left hand corner of the window. This will bring you back to the root directory of the SEURAT data disk.

Double-click on the COLRFILL folder icon and copy ARCX.TTP and COLRFILL.ARC into it. As before, un-ARC COLRFILL.ARC, delete ARCX.TTP and COLRFILL.ARC and return to the root directory by clicking on the close window. Repeat this procedure for MONOFILL.ARC and PALETTES.ARC. There is no archive file for BLOCKS, but you can use this folder to store your own blocks.


Ready to Go

Now you're finally ready to run SEURAT! Put the program disk in the drive and double-click on GFABASRO.PRG and select SEURAT.BAS. In a few seconds you'll see SEURAT's main menu screen. Now you can start creating your artistic masterpieces. Be sure to refer to the button-by-button quick reference list in the SEURAT article and the SEURAT.DOC documentation file so you won't miss out on any of this programs myriad features. If you want to load or save fill patterns, brushes or palettes, put the data disk in drive B (or take out the program disk and put the data disk in drive A after SEURAT has loaded). If you have any DEGAS fill patterns you want to use in SEURAT, you can convert them using the conversion program on the disk. Double-click on GFABASRO.PRG and select CVERTFIL.BAS, then follow the instructions on the screen.

One final note: SEURAT requires a great deal of memory. You must have at least one megabyte of memory to run it. If you still receive an "Out of Memory" error, disable your desk accessories and any RAMdisks you may have installed, reboot the computer and try again. Have fun with SEURAT, and be sure to share with us your comments and suggestions regarding this program.


Some Code Extravaganza!

The compiled version of SEURAT was too large to fit on the START disk, even in an archive file so were publishing the tokenized GFA BASIC listing and the GFA BASIC run-only program instead. (If you own the GFA BASIC compiler, we do recommend that you compile SEURAT as this will improve the programs speed.) This way we can bring you not only a great ST graphics program but its complete source code as well! If you have MichTrons GFA BASIC 2 0 interpreter, you can load SEURAT.BAS to see just how it works and, best of all, you can customize it to your heart's content. Since START published GFA BASIC 2.0 in January, if you don't have the interpreter you can order it from us now. The back issue magazine with disk is $14,95; the disk only (with a quick reference command list on disk) is $10.95. You can also order the GFA BASIC 2.0 manual from us for $9.95 plus $3.50 shipping and handling. Call (800) 234-7001 to order.