<><><><><><>¢ This article taken from Z*MAG issue¢ 202. Tidied by Dean Garraghty, and¢ reprinted by THE OL' HACKERS ATARI¢ USERS GROUP, with thanks.¢ ================¢ *CAROLYN'S CORNER by Carolyn Hoglin¢¢ This month's column is a departure¢ from my usual discussion about word¢ processing. But it does involve¢ printing - the printing of color¢ graphics.¢¢ So far as I am aware, there are only¢ two programs for the 8-bit Atari that¢ will print screen graphics in full¢ color: YEMACYB/4, by Michael L.¢ Clayton; and PicPrint, by Kyle Dain.¢¢ Each of these programs is designed¢ for Epson-compatible printers using¢ four-color ribbons. They employ a¢ clever combination of yellow, red,¢ blue, and black in dot patterns¢ created in a 4 x 4 matrix that result¢ in a hardcopy printout that may¢ include any or all of the 128 colors¢ available on the 8-bit Atari. Sample¢ picture files are included with each¢ program.¢¢ Having only four colors in a color¢ ribbon would seem to allow only seven¢ hues plus the white of the paper,¢ since red and yellow make orange, red¢ and blue make purple, and blue and¢ yellow make green (didn't I learn¢ that in kindergarten?). However, the¢ program analyzes the color of each¢ pixel on the screen and mixes the¢ colors of the ribbon in varying¢ proportions in an attempt to achieve¢ a printout that matches the screen¢ display as closely as possible.¢¢ A color's dot pattern may be made up¢ of only one dot for a very pastel¢ effect, or as many as 16 for the¢ brightest hue. For instance, a pale¢ pink might use only the red ribbon in¢ a pattern of widely separated dots,¢ allowing a lot of white to dilute the¢ red. Orange would be achieved by¢ printing yellow followed by red. ¢ Yellow and red would each be printed¢ in the dot pattern required by the¢ shade of orange in the picture. Each¢ pass of the printhead prints first¢ yellow, then red, blue, and black as¢ required by the program's color¢ analysis.¢¢ Paint programs usually employ¢ GRAPHICS 15 which allows your choice¢ of four colors per picture consisting¢ of 192 rows of 160 pixels each. To¢ increase the apparent number of¢ colors in a picture, a variety of¢ patterns composed of the four colors¢ are provided. YEMACYB/4 and PicPrint¢ faithfully reproduce these patterns¢ as well as the solid colors. With¢ the judicious use of DLI's (Display¢ List Interrupts - usually only¢ understood by advanced programmers),¢ a picture can even display all 128¢ colors at the same time.¢¢ I have found that pictures loaded¢ into either of these fine programs¢ produce printouts virtually identical¢ to one another. However, the¢ programs themselves differ in many¢ ways.¢¢¢ YEMACYB/4¢¢ You may have guessed that the title¢ of this program (pronounced "YEM-a-¢ sibe") comes from the hues of a¢ standard color ribbon - yellow,¢ magenta, cyan, and black. (Magenta¢ and cyan look pretty much like red¢ and blue to most of us.)¢¢ Incidentally, the original version of¢ this program ("YEMACYB" without the¢ "/4") is for non-color Epson-¢ compatible printers and involves¢ passing the same sheet of paper¢ through your printer four times using¢ individual yellow, red, blue, and¢ black ribbons. The program provides¢ a means of precisely aligning the¢ paper before each pass. While the¢ procedure is rather tedious and time-¢ consuming, the final result is the¢ same as if printed on an Epson JX-80¢ or a Star NX-1000 Rainbow.¢¢ This program requires BASIC, but is¢ self booting. There are no DOS or¢ AUTORUN.SYS files on the program¢ disk, nor are they necessary. Only¢ Drive 1 is supported. The program¢ documentation states that your¢ graphic file must be in standard 62-¢ sector format (either GRAPHICS 7 or¢ GRAPHICS 7+ [GRAPHICS 15]), but I¢ found that it would load some, but¢ not all, compressed files as well.¢¢ After the file is loaded, the picture¢ is displayed on the screen. Touching¢ a key brings you to the color change¢ menu. At this point, you may choose¢ to change your picture to monochrome. ¢ Or, if you are printing in color,¢ here is where you have the¢ opportunity to change the colors in¢ each register (line by line, if you¢ wish). Unless you have a listing of¢ the pokes to memory locations 708,¢ 709, 710, and 712, and the colors¢ they produce, this is likely to be a¢ lengthy trial-and-error procedure. ¢ You may also load DLI data that has¢ been saved on disk. When you have¢ finished your changes, the picture is¢ redisplayed for your approval. You¢ may go back to the color change menu¢ as many times as necessary. There is¢ no provision to restore the original¢ colors, or to go from monochrome back¢ to color without reloading the¢ picture.¢¢ When you are satisfied with your¢ picture, you have the opportunity to¢ save the color changes you have made. ¢ This color data is not saved in a DOS¢ format, but is unconditionally¢ written, for future use, on the last¢ six sectors of whatever single-¢ density disk is in the drive.¢¢ My test picture took about 15 minutes¢ to print and was centered on the¢ paper both vertically and¢ horizontally. The number of the¢ column being printed is displayed on¢ the screen, beginning with 159 and¢ counting down to 0. While printing¢ is in progress, it can be either¢ paused temporarily or aborted.¢¢ With the differences among monitors,¢ printers, ribbons, and paper, you may¢ find that the printout does not match¢ the screen display exactly. Included¢ with YEMACYB/4 is a separate utility¢ program to create your own modified¢ color pallette to use instead of the¢ default pallette provided.¢¢ There are five more utility programs¢ provided, as well as a menu to select¢ them from. You must first load your¢ favorite DOS, then run MENU.BAS.¢¢ The program YFLIPPER.BAS will mirror¢ flip a Micropainter picture file in¢ GRAPHICS 7 or GRAPHICS 15, and resave¢ it to disk.¢¢ YSAVUSCR.BAS enables you to capture¢ to disk a GRAPHICS 7 or GRAPHICS 15¢ picture that is displayed in a BASIC¢ program.¢¢ YDLISCON.BAS will convert that DLI¢ data from the last 6 sectors to a DOS¢ file and back again.¢¢ YBAREBON.BAS is a few-frills GRAPHICS¢ 7 editor with text entry capability.¢¢ YWINDOWS.BAS confused me. ¢ Documentation needs to be provided¢ for this program.¢¢ YEMACYB/4 is a powerful program that¢ does what it claims very well indeed. ¢ A very nice feature is the file¢ COLCHART.PIC which creates a full-¢ screen 128-color display that also¢ functions as a reference color chart¢ when printed. The DLI data on the¢ program disk makes this possible. ¢ This reference chart is a great help¢ when creating a custom pallette. The¢ documentation includes a chart of the¢ 45 dot patterns used to create¢ various hues which makes the concept¢ much more understandable.¢¢ On the negative side, I found the¢ program somewhat awkward to use at¢ times, and wished it were possible to¢ redisplay my picture without going¢ round and round in the menu. If you¢ load the wrong picture by mistake,¢ you must proceed as if you intend to¢ print it through quite a few commands¢ before finally being offered the¢ option of starting over.¢¢ Michael L. Clayton¢ Electronical Software¢ P.O. Box 8035¢ Rochester, MI 48063¢ (313) 942-9504¢¢¢ PicPrint¢¢ This program is extremely user¢ friendly and has the immediate¢ advantage of being able to load and¢ display graphic files from just about¢ any paint program written for the 8-¢ bit Atari. In many cases the program¢ automatically identifies the type of¢ graphic file and displays it¢ accordingly. A few files produced by¢ programs using GRAPHICS 7, GRAPHICS¢ 8, or mixed screens are loaded by¢ pressing console keys according to¢ instructions.¢¢ Another advantage is that it supports¢ not only Epson-compatibles, but also¢ Atari XMM-801, and Canon thermal¢ printers, in color or black-and-¢ white. All drives are supported,¢ including ramdisks. After the picture¢ is loaded, it is displayed with an¢ overlaid menu window which provides a¢ great many useful options. Pressing¢ "V" allows viewing of the entire¢ picture until another key is pressed¢ to bring back the menu.¢¢ If you have selected a non-color¢ printer, your picture is shown in¢ monochrome. If you have a color¢ printer, but want to make a¢ monochrome printout (using a black or¢ another single-color ribbon), you can¢ change the display to black and¢ white.¢¢ In either case, you can change each¢ color register by choosing its number¢ (1 through 4) and then pressing + or¢ - keys. I especially like the way¢ you get instant feedback when making¢ these changes.¢¢ Display List Interrupt data cannot be¢ originated from the program, but¢ pressing "D" will load the .P? files¢ from Philip Price's PD Painter¢ program files. These files provide¢ for displaying up to 128 colors in¢ one picture. The DLI's won't show on¢ your screen, but they will print on¢ paper. You may also flip your picture¢ - very useful for making T-shirt¢ iron-ons.¢¢ Pictures may be changed to and from¢ GRAPHICS 8 monochrome mode. Whether¢ you actually see monochrome on your¢ screen depends upon what kind of¢ Atari and monitor you are using. If¢ you have an XE computer that outputs¢ separate chroma and luma and a¢ monitor and cord that supports this,¢ the picture appears in black and¢ white. If you are using an XL¢ computer, or your monitor or cord¢ only supports composite video, you¢ may see a lot of purple and green due¢ to artifacting. Since these colors¢ are not "real" colors, they will not¢ be printed as such, even on a color¢ printer.¢¢ In this GRAPHICS 8 mode, you can also¢ switch to a negative image. This is¢ great for pics that normally display¢ white on a black background.¢¢ Another plus is that you can restore¢ colors in GRAPHICS 15 pics if you¢ messed them up or have changed them¢ to black and white.¢¢ You can save your picture in standard¢ 62-sector uncompressed format for use¢ with other programs.¢¢ If you press "C", the values of the¢ color registers will be shown on the¢ screen (behind the menu window). ¢ Unless you also want them on your¢ printed picture for some reason, I¢ don't advise using this option, as¢ there is no way to undo it short of¢ reloading your picture!¢¢ When you are ready to print your¢ picture, you can use console keys to¢ enable double strike (great when your¢ ribbon is fading) and/or disable¢ ANTIC DMA to speed up the printing. ¢ (For some reason, this last feature¢ didn't work for me.) The test picture¢ I printed took about 18 minutes to¢ finish. A nice touch is the moving¢ bar on screen indicating printing¢ progress. The printout will be¢ centered horizontally, but not¢ vertically, so you need to set your¢ paper so that printing begins about¢ one inch from the top.¢¢ There are many factors that affect¢ matching the colors on screen to the¢ colors printed on paper. Try¢ displaying the same picture on two¢ different monitors, or on a monitor¢ and a TV set. They seldom are the¢ same. So which one is PicPrint to¢ match? If you can see that the¢ colors are not going to satisfy you,¢ you can abort the printing, reload¢ the pic and adjust the colors. There¢ is no programmed pause-and-resume-¢ printing feature, but I noted that¢ setting my printer off-line did not¢ cause an error for a good 30¢ seconds.¢¢ Included on the program disk are two¢ valuable utility programs.¢ CONVERT.COM will convert pics to and¢ from GRAPHICS 8, ST PI3, and IBM¢ monochrome format. PAINTR.COM is¢ Philip Price's DLI program. A brief¢ explanation of PAINTR.COM is included¢ with PicPrint, but you should really¢ read the documentation in ANTIC¢ Magazine's September 1984 issue to¢ get the full benefit of this¢ sophisticated and powerful program.¢ Patrick Dell'era's enhancements to¢ this program are documented in¢ ANTIC's March 1985 issue.¢¢ PicPrint is a compiled TurboBasic¢ program and must be run on an Atari¢ XL or XE computer. It will not run¢ correctly under the OmniView OS, and¢ you must be sure to disable BASIC¢ when booting. If I could change¢ anything, I would add the ability to¢ pause the printout, and possibly¢ disable BASIC automatically. But¢ this is nitpicking. If you have a¢ color printer (or even if you don't),¢ contact Kyle Dain to purchase¢ PicPrint!¢¢ Kyle Dain¢ MKD Systems¢ 125 Goodview Drive¢ Apollo, PA 15613¢ (412) 727-7987¢ *+*+*+*+*¢
