1Libnetpbm PPM Drawing FunctiLoinbrMaarnyuaFlu(n3cL)tiibonnestpMbamnuPaPlM Drawing Function Manual(3)
2 Table Of Contents ⟨#toc⟩
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8 libnetpbm_draw \- Libnetpbm PPM Drawing Function Manual
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11 This reference manual covers functions in the libnetpbm library for
12 drawing images, using the PPM image format and the libnetpbm in-memory
13 image formats.
14 We actually have very little information here; this is mainly a frame‐
16 work for adding documentation later if someone becomes interested in
17 this facility.
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22 The functions are all declared in the ppmdraw.h header file.
23 ppmd_point_drawproc
26 ppmd_setlinetype
27 ppmd_setlineclip
28 ppmd_line
29 ppmd_spline3
30 ppmd_polyspline
31 ppmd_circle
32 ppmd_filledrectangle
33 ppmd_fill_drawproc
34 ppmd_fill
35 ppmd_text
36 ppmd_text_box
38 The ppmd_text and ppmd_text_box functions use fonts. You control the
39 fonts using functions described in this section. There is one font
40 that comes with Netpbm, called 'standard'. It is built into the func‐
41 tion library and is the default font. You can create additional fonts
42 and use them instead.
43 In a program that uses Netpbm drawing facilities, there is a 'current
45 font.' all drawing of text uses the current font. When the program
46 starts, the current font is 'standard'; you can change it after that by
47 calling the ppmd_set_font function.
48 Other than a built-in font, a font lives in file in a format special to
50 Netpbm called Ppmdfont. The file typically has a name that ends in
51 '.ppmdfont'.
52 Use the ppmddumpfont program to dump the contents of a Ppmdfont file in
54 human readable format.
55 Use the ppmdmkfont program to generate the 'standard' font as a Ppmd‐
57 font file. You don't normally need to do this, becuase 'standard' is
58 built into libnetpbm.
59 Use the ppmdcfont program to turn a Ppmdfont file into a C source file
61 that you can compile into a program as a built-in font. Though we
62 don't give full instructions here on how to do that, libnetpbm's built-
63 in 'standard' font is a good example. In Netpbm source code, you will
64 find the C source file standardppmdfont.c, which was generated from the
65 file standard.ppmdfont by ppmdcfont. You simply use a pointer to the
66 structure that the C file defines as a font handle, just like one you
67 would get from ppmd_read_font.
68
72 The font file starts with the characters 'ppmdfont' (without the quota‐
73 tion marks) in ASCII.
74 The rest of the format is not yet documented, but it generally
76 describes, for each code point, a sequence of straight line plotting
77 commands to form the glyph for the indicated character. I.e. it is a
78 vector, not raster, font.
79
83 These functions are declared in the header file ppmdfont.h.
84 ppmd_read_font
87 This function associates a Ppmdfont file, which you identify by naming
88 the Ppmdfont file, with a handle that you can use to identify the font
89 to other functions. Technically, this function reads the font into
90 memory.
91 ppmd_free_font
94 This function releases the handle that you get from ppmd_read_font. It
95 frees resources associated with it; you can't use the handle after
96 this.
97 ppmd_get_font
100 This function returns the handle of the currently selected font.
101 ppmd_set_font
104 This function sets the currently selected font. You identify the font
105 to which to set it with a handle such as you get from ppmd_read_font or
106 ppmd_get_font.
107netpbm documentation SeptembLeirbn2e0t0p5bm PPM Drawing Function Manual(3)