13.4. Built-in Module drawf

For more details see the documentation on the draw file format, and the DrawFile module.

Errors are reported as exceptions; the usual exceptions are given for type, index and value errors, while draw specific errors raise drawf.error as described below.

Module drawf defines the following data items:

error -- exception of module drawf

This exception is raised on draw specific errors (e.g., not for illegal argument types). Its string value is 'drawf.error'. The accompanying value is a string describing the error.

load (filename) -- function of module drawf

Creates a new drawf object containing the drawfile loaded from the named file.

new () -- function of module drawf

Creates a new empty drawf object.

size -- data of module drawf

Returns the length in bytes of the drawfile.

box ([n]) -- function of module drawf

Returns the bounding box of object number n, or of the whole file if no n is given. The result is a tuple of 4 integers.

find (x,y [, n]) -- function of module drawf

Returns the index of the first object in the drawfile whose bounding box contains (x,y), or the first object after object n if n is given.

fonttable (fontdict) -- function of module drawf

Adds a font table object at the end of a diagram. This would normally be called for an empty diagram, as there should only be one such object, and it must preceed all text objects. fontdict is a dictionary with keys the font number, and values the font names.

group (drawf) -- function of module drawf

Appends the contents of drawf as a group object.

path (pathdesc,style [, dashpattern , dashstart]) -- function of module drawf

Adds a path. pathdesc is a list consisting of integers or pairs of integers. The data is that required for a draw path component, except the initial move and final end are added automatically. The style is a tuple of 4 integers representing the fill colour, outline colour, outline width and path style description.

The dashpattern is a list of integers representing lengths of dash elements. dashstart is an integer representing the distance into the pattern to start, it defaults to zero. The dash pattern bit of the style description word is set automatically according to the presence of a dash pattern.

pathcolour (colour [, n ...]) -- function of module drawf

Sets the colour of paths. If no n is given all paths in the diagram are changed, otherwise the n must be indices of path or group objects. The path objects have their colours changed. The group objects are searched recursively for paths.

pathfill (colour [, n ...]) -- function of module drawf

Sets the fill colour. n is as for pathcolour.

render (flags,trans,clip,flat) -- function of module drawf

Renders the diagram. flags and flat are integers. trans is the address of a block of 6 integers. clip is the address of a block of 4 integers. See the documentation of SWI DrawFile_Render for details.

save (filename) -- function of module drawf

Saves the contents as a drawfile with name filename.

text (point, text, style) -- function of module drawf

Adds a text object. point is a pair giving the x and y coordinates of the start of the text base line. text is the text to print. style is a tuple of 5 integers, the text colour, text background colour hint, font number, and x and y sizes of the font. The sizes are in point.

textbackground (colour [, n ...]) -- function of module drawf

Sets the text background colour hint. n is interpreted as for pathcolour but using groups and text objects.

textcolour (colour [, n ...]) -- function of module drawf

Sets the text colour. n is interpreted as for pathcolour but using groups and text objects.

Colours are integers of the form 0xbbggrr00 or-1 for transparent.