PAYNE@ITHACA.BITNET (John Payne) (06/15/87)
Can anyone shed any light on printing sixel format data on an LN03? The documentation in the LN03 Programmer Reference Manual is unclear, at least to me. I need help with the parameters on the device control string that throws the LN03 into sixel mode. I would like to get varieties of grid sizes (dots per inch) while maintaining a 1:1 aspect ratio (square size pixels). I was able to get a 1:1 ratio at (roughly) 74 dots per inch using the sequence <ESC>P9;0;0q, but haven't been able to adjust the parameters for higher resolution square pixels. There is also a reference in the manual to a "raster attributes" control character (DECGRA), which is also unclear to me. Can anybody help? Thanks. John Payne Phone: (607) 274-3704 Academic Computing Services Bitnet: PAYNE@ITHACA Ithaca College Internet: PAYNE%ITHACA.BITNET@WISCVM.WISC.EDU Ithaca, NY 14850
MCGUIRE@GRIN2.BITNET.UUCP (06/18/87)
> Date: Mon, 15 Jun 87 08:36 EDT > From: John Payne <PAYNE%ITHACA.BITNET@WISCVM.WISC.EDU> > Subject: LN03 Sixel Graphics > > Can anyone shed any light on printing sixel format data on an LN03? > The documentation in the LN03 Programmer Reference Manual is unclear, > at least to me. > > I need help with the parameters on the device control string that > throws the LN03 into sixel mode. I would like to get varieties > of grid sizes (dots per inch) while maintaining a 1:1 aspect ratio > (square size pixels). I was able to get a 1:1 ratio at (roughly) > 74 dots per inch using the sequence <ESC>P9;0;0q, but haven't > been able to adjust the parameters for higher resolution square > pixels. > > There is also a reference in the manual to a "raster attributes" > control character (DECGRA), which is also unclear to me. If Digital had correctly documented DECGRA, you would not have had a problem. In the device control string which selects sixel mode, take the default ps1 and ps2, and specify the horizontal pixel width in ps3 (in 720/inch units (decipoints), or, if you use the SSU sequence, 300/inch units (pixels). Begin the sixel data with the DECGRA control sequence. the sequence defines the aspect ratio of the pixels. A 2:1 (vertical:horizontal) ratio causes pixels to be twice as high as they are wide. The format of the sequence is not in the manual (EK-OLN03-RM-002, 2nd edition, November 1985). I arrived at the format by trial and error. Add a note to page 130 of the manual as follows. "vertical;horizontal Replace `vertical' with the vertical component of the ratio, and `horizontal' with the horizontal component. Finally, here's an example of a sequence that would be imaged using pixels that are 1/36" in both dimensions. It assumes that the current size unit is decipoints. <DCS>;;20q"1;1sixeldata<ST> Good luck! Ed <MCGUIRE@GRIN2.BITNET> P.S. I hope I've got this right. I never could think very well in decipoints! :-)