Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!execu!sequoia!rpp386!woody From: woody@rpp386.cactus.org (Woodrow Baker) Newsgroups: comp.lang.postscript Subject: Re: Bitmap of PostScript code.. Summary: some more thoughts Message-ID: <18001@rpp386.cactus.org> Date: 20 Feb 90 19:55:17 GMT References: <1990Feb14.041704.14844@athena.mit.edu> <2761@bacchus.dec.com> <144@heaven.woodside.ca.us> Organization: River Parishes Programming, Plano, TX Lines: 70 some more bitmap thoughts... While postscript is indeed a raster type language, and your points on that are very well taken, and said, it should be realized that the core graphics primatives are just as applicable to vector devices. Now, while it would be difficult to implement gray shades on a MECHANICAL vinyl cutter, there does exist as subset of ps, consisting of the curveto, arcto, lineto,moveto and relative versions, as well as the transforms that are very applicable. An implementation that could only do black or white (material removal or not) is a useful and valid set of postscript. It would not be difficult to do grayshades and fills on a waterjet cutter, abrasive stream cutter, or lasercutter for fabrics, wood, vinyl, paper, metal etc. These are typicaly vector devices. The cutter stays stationary, and the table holding the material to be cut, moves, and moves directly from point A to point B, not via rastering. A related device is the TEKTRONICS 4015 type terminal. A vector device, that could be made to run PS rather nicely. Many of these would not need a bit map, and thus the arguement that bitmaps are perhaps needed would not hold for some of these, although the COULD be implemented via a bitmap. The bitmap is the "rosetta stone" of the graphics world. Postscript is not. What I mean, is that a bitmap is the lowest common denominator for graphics representation. If I want to move an image between a sun, or a mac, or a pc, the way to do it, is to convert bitmaps. If I want to display a mac image on my pc, I can convert the bitmap. If I digitize a video source on my pc, and wish to transfer it elsewhere, I use a bitmap. Currently there is no language to describe digitized video images. If I want to print these images, Postscript will even allow me to do that with the image operator. If I generate a page in Postscript, the bitmap should be available to other entities. Postscript won't allow that. This appears to me to be rather myoptic. Consider: I create a complex page that takes 20 min or more running under postscript. I wish to create a slide for a presentation. What are my choices? 1. Purchase an *EXPENSIVE* postscript to slide converter/printer unit. 2. Print it out, then photograph it (the most common way). Perhaps photographicaly transfer the video image to slide, or photograph the page with a video camera (losing a LOT of resoluteion) 3. Grab the bitmap, and send it to an inexpensive bitmap to slide converter, or send it to a video recorder. Now: number 3 does not do much for Adobe, as a competing media (bitmap vs postscript) output device is used. If I use a PS interpreter to generate the bitmap it does. The bottom line, is that bitmaps are VERY valuable things to have around, they may be big, but hardly ugly. They are a fact of life. The world does NOT revolve around an abstract page description language, and certainly never will, as it is not suitable for all things. Neither are bitmaps, but they are a good deal more general purpose than the page description language. I have a real problem with the attitude that "nothing else matters...We set the standard", whether it is IBM (the microchannel) or Microsoft (OS/2 ) or Alan Bradley (industrial controllers) or....... you name it. Cheers Woody Cheers Woody