Link to the main program: placemat.ps
Links to documentation: ▶︎ Introduction, and a first placemat ▶︎ Fonts and glass decoration ▶︎ Compound Strings and non‑ASCII characters ▶︎ Page‑level controls ▶︎ Arrangement of glasses on the page ▶︎ Non‑Glasses Pages ▶︎ Document‑level controls ▶︎ Type sizes ▶︎ Translations ▶︎ Code injection ▷︎ Bitmap images ▶︎ Debugging
Links, internal this page:
★ Top
★ Introduction
★ Make an EPS
★ PostScript
☆ Image data blocks
☆ PaintBackgroundInsideGlassCircles and PaintBackgroundCode
☆ PaintBackgroundInsideGlassCircles
☆ PaintBackgroundCode
★ Conclusion
Adding bitmap images is difficult. It is painful. Unless you absolutely must, don’t.
This document is for those who must.
The image needs to be in PostScript. Start with an image, appropriately cropped. The image you want is probably a brand logo, but we’ll use two images, one colour, one gray (source).
Print the image to EPS from a paint program. Some make messy EPS, which is even more difficult than otherwise needed. Henceforth it will be assumed that the EPS has been generated by Lemke Software’s GraphicConverter: ʏᴍᴍᴠ.
Resulting EPS files: colour; gray.
Let’s show the code:
/PaintBackgroundCode
{
TypeOfPagesBeingRendered /Glasses eq
{
SheetNum -1 gt % This condition always true, but a tighter condition could be used.
{
% Image centre, in this example, uses GlassPositions. But x value could have been PageWidth MgnL MgnR sub add 2 div.
GlassPositions SheetNum get 1 get 0 get GlassPositions SheetNum get 2 get 0 get add 2 div % x (hence ... 0 get)
GlassPositions SheetNum get 2 get 1 get GlassPositions SheetNum get 4 get 1 get add 2 div % y (hence ... 1 get)
translate
% DeviceRGB or DeviceGray, depending on whether image RGB or greyscale.
/DeviceRGB setcolorspace
% Width and height known from image. Also in EPS.
% Resolution: not too small.
% But, settings dependent, some PS->PDF software down-resolutions large pictures. For such setting, high resolution is needless.
<< /width 640 /height 400 >> begin
% Scaling determined by trial and error, or by computation in the PostScript, or otherwise.
0.1576991 dup scale
% Need lower-left of image, but "translate" seven lines up chose desired centre.
width -2 div height -2 div translate
<<
/DataSource ImageColour_data << >> /DCTDecode filter % data source usually needs changing
ImageColour_data 0 setfileposition % data source usually needs changing
/ImageType 1
/Width width
/Height height
/ImageMatrix [1 0 0 -1 0 height]
/BitsPerComponent 8
/Decode [ currentcolorspace 0 get /DeviceGray eq {0 1} {0 1 0 1 0 1} ifelse ]
>> image
end % << /width ... /height ... >>
} if % ... SheetNum ...
} if % Glasses page
} def % /PaintBackgroundCode
/PaintBackgroundInsideGlassCircles
{
//false [ /Glasses /TastingNotes /PrePour /NeckTags ] {TypeOfPagesBeingRendered eq {pop //true exit} if} forall % /DecanterLabels excluded.
{
WithinTitles 0 eq % Example condition. YMMV.
{
% DeviceRGB or DeviceGray, depending on whether image RGB or greyscale.
/DeviceGray setcolorspace
% Width and height known from image. Also in EPS.
% Resolution: not too small.
% But, settings dependent, some PS->PDF software down-resolutions large pictures. For such setting, high resolution is needless.
<< /width 640 /height 400 >> begin
% Scaling determined by trial and error, or by computation in the PostScript, or otherwise.
RadiiCirclearrayInside SheetNum get width dup mul height dup mul add sqrt 2 div div dup scale
% Need lower-left of image, but "translate" seven lines up chose desired centre.
width -2 div height -2 div translate
<<
/DataSource ImageGray_data << >> /DCTDecode filter % data source usually needs changing
ImageGray_data 0 setfileposition % data source usually needs changing
/ImageType 1
/Width width
/Height height
/ImageMatrix [1 0 0 -1 0 height]
/BitsPerComponent 8
/Decode [ currentcolorspace 0 get /DeviceGray eq {0 1} {0 1 0 1 0 1} ifelse ]
>> image
end % << /width ... /height ... >>
} if % WithinTitles ...
} if % /Glasses ...
} bind def % /PaintBackgroundInsideGlassCircles
/ImageGray_data
currentfile
<< /Filter /ASCIIHexDecode /Intent 0 >>
/ReusableStreamDecode filter
FFD8FFE000104A46494600010100004800480000FFE100404578696600004D
4D002A00000008000187690004000000010000001A000000000002A0020004
% !!! 2477 lines removed !!!
7F1647527BA8E878240C1AD0B7B048A4FB4DC39B8B9FF9E8DFC39EA117A28F
A727B935FFD9
> % End-of-data marker for ASCIIHexDecode data. Observe previous line doesn't end in ">".
def % /ImageGray_data
/ImageColour_data
currentfile
<< /Filter /ASCIIHexDecode /Intent 0 >>
/ReusableStreamDecode filter
FFD8FFE000104A46494600010100004800480000FFE100404578696600004D
4D002A00000008000187690004000000010000001A000000000002A0020004
% !!! 6101 lines removed !!!
1F4E7DF9C57F865E22F8B593F0CD2FF6EA97AAF6A71D64FD7F9579BB795DE8
7EBB92F0EE271D2FDD2B47AB7B7FC1F447FFD9
> % End-of-data marker for ASCIIHexDecode data. Observe previous line doesn't end in ">".
def % /ImageColour_dataIt is intended that much of this can be copy-pasted, with small alterations, into the code for your placemats.
There are four blocks of action: PaintBackgroundCode, PaintBackgroundInsideGlassCircles, ImageGray_data, ImageColour_data.
These are tackled in reverse order.
There are two blocks of image data.
- They start with the name of the variable that will hold this data. In this example the unimaginative names are
/ImageGray_dataand/ImageColour_data. - Then there are three lines to be quoted vertabim. (If you must, see p15 and p9.)
- The gray-scale image had 2481 lines of data; the colour image had 6105 lines. Likely as not, your images will have a different number of lines.
- The image data is terminated with a “>”. My preference has been that this starts a new line, but that newline is optional.
- And then a
def, which attaches that block of data to the variable name,
PaintBackgroundInsideGlassCircles and PaintBackgroundCode are code-injection parameters, with a default do-nothing value of {}.
As with any other parameter, if giving them new values, don’t forget to remove the lines setting their default values.
These two parameters are to hold code, which may do arbitrary computation, and which may paint on the page.
PaintBackgroundInsideGlassCircles is executed each time a glass circle is painted.
On execution, the graphic matrix will have already been translated such that the centre of the circle is at (0,0).
The code has a test involving TypeOfPagesBeingRendered: on what page types should the grayscale image appear?
- Of course, the glasses page?
- The glasses-page circles are reproduced, faded, on the tasting notes page. Is the image wanted there?
- The glasses-page circles are reproduced on the pre-pour pages. Is the image wanted there?
- And the various titles types, but not the circle of text, are on the neck-tag pages, and on the decanter labels. Is the image wanted on either of those? Hence page type is tested.
- Is the image wanted for all wines, or only for those for which this is the correct brand logo?
The example selects only the first:
WithinTitles 0 eq. - Is the image colour or gray? The former has three times the amount of data, so this knowledge is needed, and imparted with
/DeviceGray setcolorspaceor/DeviceRGB setcolorspace. Use of/DeviceGraywhen the data is colour can leave excess data on the stack, causing an error to appear much later in execution, hence with error reporting seemingly unconnected to image painting. - Update
<< /width 640 /height 400 >>to match the pixel dimensions of the bitmap. - The image needs to be
scaled. If being scaled by equal amounts in both directions, as is usual, the multiplier can be computed and followed bydup scale. The example is scaled to fit precisely inside the circle:RadiiCirclearrayInside SheetNum get width dup mul height dup mul add sqrt 2 div div, which works well for an image the contents of which are conveniently rectangular. But trial-and-error isn’t bad: guess 0.5; guess 0.02; go from there. - We want the point (0,0) to be the centre of the image, not its lower-left, which is done with
width -2 div height -2 div translate. - Finally, ensure that the chosen image data variable (
ImageGray_data) is the correct variable.
PaintBackgroundCode is only slightly different to PaintBackgroundInsideGlassCircles.
- It exists at the page level, so
WithinTitlesandWithinPageshould not be referenced. - On which sheet numbers should this appear? The demonstration code has a mock condition,
SheetNum -1 gt, which is always true. - Need to
translateto the desired point on the page. In this example it referencesGlassPositions SheetNum get, which is of the form[ [x0 y0] [x1 y1] … ], but the x value could have beenMgnL MgnR sub PageWidth add 2 div. - Colour image, so
/DeviceRGB setcolorspace. - And in this example, the
scalecomes directly as a number,0.1576991 dup scale, rather than being computed in the PostScript. As before, trial-and-error suffices (though Mathematica is more precise).
Adding bitmap images is difficult. Unless you absolutely must, don’t.
But if you must, then you must. Do it well. Good luck.