From 3ad720e23a52f07045612833e56d0fcf94f988c8 Mon Sep 17 00:00:00 2001 From: reinelt <> Date: Sun, 26 Mar 2000 20:00:44 +0000 Subject: [lcd4linux @ 2000-03-26 20:00:44 by reinelt] README.Raster added --- README.Raster | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 README.Raster (limited to 'README.Raster') diff --git a/README.Raster b/README.Raster new file mode 100644 index 0000000..b0e05b4 --- /dev/null +++ b/README.Raster @@ -0,0 +1,49 @@ +# +# $Id: README.Raster,v 1.1 2000/03/26 20:00:44 reinelt Exp $ +# + +This is the README file for the Raster display driver for lcd4linux + +This driver is intended to create various raster formats, at the moment +only binary PPM (portable pixmap) is supported. + +The driver creates the output file(s) specified with the -o switch. The +parameter is used as a format string for sprintf(), if you specify '%d' +in the output file, files with a sequence number will be created. + +The output file is first created with a '.tmp' extension, this temporary +file will be written and closed, and finally (atomically) renamed. This way +you can be shure that you will always get a complete file, but its contents +changes every 'tick' milliseconds. + +Configuration: + +The driver needs/supports the following entries in lcd4linux.conf: + +Display: must be "PPM" +size: [columns]x[rows], e.g. "20x4" +font: [xrex]x[yres], at the moment only "5x8" and "6x8" supported. +pixel: [pixelsize]+[pixelgap], e.g. "5+1" +gap: [row gap]x[column gap], e.g. "3x3" +border: border width +foreground: color of an active LCD Pixel, must be #rrggbb +halfground: color of an inactive LCD Pixel, must be #rrggbb +background: backlight color, must be #rrggbb + +This may look weird, but it is weird. Let's explain this a bit further: +The raster driver tries to emulate a real LC display. A real LCD has a +size of columns*rows characters. Each character consists of xres*yres +LCD cells. One single cell will be represented by a rectangle of +pixelsize*pixelsize pixels. If you want to, you can emulate the gap +between this lcd cells by specifying a pixelgap greater than zero. +Sometimes there's a gap between characters, too. You can specify this +gap (in pixels again) horizontally and vertically. Usually this gap +is the same size as a cell (which is pixelsize+pixelgap). + +If you use a font of 5x8, some characters may use the first and the last +pixel. So you should specify a column gap, otherwise the caracters may +touch. On the other hand, the 6x8 font never uses the first pixel. So you +can omit the column gap, and will get the same text layout, but +uninterupted bars! + +After all: don't try to understand this unless you have tried it out! -- cgit v1.2.3