QRT Machine Specific Instructions The QRT ray tracer is designed to run on any computer with sufficient graphics capabilities. The machine should have a resolution of at least 128K dots/screen, and be able to display color graphics. At least 256 simultaneous colors are needed for acceptable images; however, it may be possible to display rudimentary images with as little as 64 colors. The QRT program itself is the same across computers; only the QRT post processor differs. QRT computes the image internally with a much higher color resolution than most computers have (16 million simultaneous colors), and the post processor maps this image to the available palette. This document describes the machine dependent details of the post processor. On most computers the following naming convention is recommended: File Suffix Example QRT input .QRT IMAGE.QRT QRT text output .OUT IMAGE.OUT QRT bitmap output .RAW IMAGE.RAW QRTpost converted file .PIC IMAGE.PIC QRT Ray Tracer Page 1 Machine Specifics Commodore Amiga QRT was designed and written on the Commodore Amiga. Unlike many machines, the Amiga has a very standard graphics file format which nearly any graphics program can read. Two steps are necessary to transform the QRT output file to the graphics file format (IFF/HAM). First, the QRT post processor is run. Second, a separate program (RAY2) compresses the post processor output into IFF file format for viewing with any "iff-show" type program. QRT can be run in the background on the Amiga. It should be run with a low task priority so that it will not interfere with normal operation of the computer. At least one megabyte is recommended, and the QRT output file should be sent to a RAM disk or hard drive. It is possible to send it to a floppy disk, but the disk will constantly be accessed for the duration of the image creation time. It will probably be necessary to increase the default process stack size with the STACK command. A stack size of 40K or more is recommended to avoid stack overflow errors; however, some images require as much as 80k of stack space. Color Resolution: 4096 colors from palette of 4096 QRT Output File Size Approx. 400K bytes Commands to run QRT SetTaskPriority -5 run QRT IMAGE.OUT SetTaskPriority 0 Commands to run QRTPost QRTPost IMAGE.RAW IMAGE.TMP RAY2 IMAGE.TMP File Naming Restrictions Length <= 63 Characters May include special symbols: ex. '_', '#', etc. Although the operating system supports imbedded spaces in files, neither QRT nor QRTPost does. QRT Ray Tracer Page 2 Machine Specifics Data General MV10000 The Data General DG1000 terminal has a high display and color resolution, so the resulting QRT output file is large. QRT should be run in the background on this machine. The resulting picture file may be displayed with the DISP program (G. Radack). Although the Data General is capable of a resolution of 1280 x 1024, there have been problems allocating this much memory with the DISP program. Therefore, the DG version of QRT will not use the entire display. The largest possible bitmap file size has not yet been determined. Color Resolution: 256 colors from palette of 16 Million QRT Output File Size Approx. 4 Megabytes at full resolution (1280 x 1024) Commands to run QRT QRT IMAGE.OUT & Commands to run Post Processor QRTPost IMAGE.RAW IMAGE.PIC disp IMAGE.PIC File Naming Restrictions Length <= 31 characters May include special symbols, but not imbedded spaces QRT Ray Tracer Page 3 Machine Specifics IBM PC or AT with EGA Graphics The IBM is capable of a relatively high display resolution, although the color palette is quite limited. The machine does not permit background tasks, so the ray tracer should be run when the machine may be left unoccupied for a long time. The output should be sent to a hard disk or extended memory drive. The IBM version of QRTPost is not yet complete as of the writing of this document. The QRT program itself is working on the IBM, but it should be run on an IBM with at least an 8 mHz 80286 and floating point co-processor. (Otherwise, it will take nearly forever). A 386 would be better yet. Color Resolution: 64 colors from palette of 64 QRT Output File Size Approx. 800K Commands to run QRT QRT IMAGE.OUT Commands to run Post Processor QRTPost IMAGE.RAW IMAGE.PIC File Naming Restrictions Length <= 8 characters with 3 character extension No special characters may be included QRT Ray Tracer Page 4 Machine Specifics Hewlett Packard 9000 Series The HP 9000's are a series of technical workstations with high resolution (up to 1280x1024) display resolution. They come in two architectures: Motorola 680x0 or HP Precision Architecture. QRT has been tested on the following machine types: 320 - (16 mhz 68020 + 68881) 360 - (25 mhz 68020 + 68881) 370 - (33 mhz 68030 + 68882) 835 - (HP Precision Architecture) (The 835 is *fast* - it can run 320 x 400 images in less than 3 and a half minutes for most images, and less than 1 and a half for simple ones, where it takes my poor 68000 based Amiga 4 hours, and 30 minutes, respectively). The 370 is no slowpoke either. Color Resolution: (depends on display card) Up to 16 million colors from the same size palette. QRT Output File Size Huge. It depends on the resolution. Commands to run QRT nice QRT IMAGE.OUT & Commands to run Post Processor qrt2gif IMAGE.RAW File Naming Restrictions Length <= 256 characters QRT Ray Tracer Page 5 Machine Specifics Macintosh II I've never seen Mac II generated QRT images, but they should look quite nice (640x480x256 colors). There may be a few problems compiling QRT on the Mac II given the non-command line operating system. Color Resolution: Up to 256 colors from a palette of 16 million. QRT Output File Size Approximately 920 K bytes. Commands to run QRT Double click on QRT icon. Then, type in QRT command line parameters. Commands to run Post Processor Double click on icon File Naming Restrictions Unknown QRT Ray Tracer Page 6 Machine Specifics