* A sparse (but complete) sample font. * * 1. Assemble this file (assumed to have been saved as "suits8.asm"). For example, if you have the * CAPE 680x0 assembler, and you have assigned "include:" to the directory containing your include * files, use: * CAsm -a "suits8.asm" -o "suits8.o" -i "include:" * * Link "suits8.o". For example, if you have Lattice, use: * BLink from "suits8.o" to "suits8" * * 2. Create the subdirectory "Fonts:suits". Copy the file "suits8" (created in step 1) * to "Fonts:suits/8". * * 3. Create a font contents file for the font. You can do this by two methods: * * a. Run the program "System/FixFonts" which will create the file "Fonts:suits.font" * automatically. * b. Use the NewFontContents() call in the diskfont library to create a FontContentsHeader * structure, which can be saved in the Fonts: directory as "suits.font". This is essentially * what FixFonts does. * * The next word contains the font YSize; in this case, 0x0008. * * The next byte contains the font Flags, in this case 0x00. * * The last byte contains the font characteristics, in this case 0x60. This says it is a disk-based * font (bit 1 set) and the font has been removed (bit 7 set), saying that the font is not currently * resident. * * Summary of suits.font file: * * Name: fch_FileID fch_NumEntries fc_FileName fc_YSize fc_Flags fc_Style * Size: word word MAXFONTPATH bytes word byte byte * Hex: 0f00 0001 73756974732F3800 0008 00 60 * ASCII: s u i t s / 8 \0 * * The correct length of a font file may be calculated with this formula: * length = ((number of font contents entries) * (MAXFONTPATH+4)) + 4. In this case (one entry), * this becomes (MAXFONTPATH + 8) or 264. * * To try out this example font, do the following. Use the Fonts Preferences editor or a * program that allows the user to select fonts. Choose the "suits" font in size 8. * This example font defines ASCII characters 'a' 'b' 'c' and 'd' only. All other characters * map to a rectangle, meaning "character unknown". section text,code INCLUDE "exec/types.i" INCLUDE "exec/nodes.i" INCLUDE "libraries/diskfont.i" MOVEQ #-1,D0 ; Provide an easy exit in case this file is RTS ; "Run" instead of merely loaded. DC.L 0 ; ln_Succ * These five entries comprise a Node structure, DC.L 0 ; ln_Pred * used by the system to link disk fonts into a DC.B NT_FONT ; ln_Type * list. See the definition of the "DiskFontHeader" DC.B 0 ; ln_Pri * structure in the "libraries/diskfont.i" include DC.L fontName ; ln_Name * file for more information. DC.W DFH_ID ; FileID DC.W 1 ; Revision DC.L 0 ; Segment * The next MAXFONTNAME bytes are a placeholder. The name of the font contents file (e.g. * "suits.font") will be copied here after this font descriptor is LoadSeg-ed into memory. The Name * field could have been left blank, but inserting the font name and size (or style) allows one to * tell something about the font by using "Type OPT H" on the file. fontName: DC.B "suits8" ; Name * If your assembler needs an absolute value in place of the "length" variable, simply count the * number of characters in Name and use that. length EQU *-fontName ; Assembler calculates Name's length. DCB.B MAXFONTNAME-length,0 ; Padding of null characters. font: DC.L 0 ; ln_Succ * The rest of the information is a TextFont DC.L 0 ; ln_Pred * structure. See the "graphics/text.i" include DC.B NT_FONT ; ln_Type * file for more information. DC.B 0 ; ln_Pri DC.L fontName ; ln_Name DC.L 0 ; mn_ReplyPort DC.W 0 ; (Reserved for 1.4 system use.) DC.W 8 ; tf_YSize DC.B 0 ; tf_Style DC.B FPF_DESIGNED!FPF_PROPORTIONAL!FPF_DISKFONT ; tf_Flags DC.W 14 ; tf_XSize DC.W 6 ; tf_Baseline <----* tf_Baseline must be no greater than DC.W 1 ; tf_BoldSmear * tf_YSize-1, otherwise algorithmically- DC.W 0 ; tf_Accessors * generated styles (italic in particular) DC.B 97 ; tf_LoChar * can corrupt system memory. DC.B 100 ; tf_HiChar DC.L fontData ; tf_CharData DC.W 8 ; tf_Modulo <- * add this to the data pointer to go from from ; * one row of a character to the next row of it. DC.L fontLoc ; tf_CharLoc <---------------- * bit position in the font data DC.L fontSpace ; tf_CharSpace * at which the character begins. DC.L fontKern ; tf_CharKern * The four characters of this font define the four playing-card suit symbols. The heart, club, * diamond, and spade map to the lower-case ASCII characters 'a', 'b', 'c', and 'd' respectively The * fifth entry in the table is the character to be output when there is no entry defined in the * character set for the requested ASCII value. Font data is bit-packed edge to edge to save space. fontData: ; 97 (a) 98 (b) 99 (c) 100 (d) 255 DC.W $071C0,$08040,$070FF,$0F000 ; < X X X X > DC.W $0FBE3,$0E0E0,$0F8C0,$03000 ; .@@@...@@@. .....@..... ...@... ....@@@.... @@@@@@@@@@@@ DC.W $07FCF,$0F9F3,$026C0,$03000 ; @@@@@.@@@@@ ...@@@@@... ..@@@.. ...@@@@@... @@........@@ DC.W $03F9F,$0FFFF,$0FFC0,$03000 ; .@@@@@@@@@. .@@@@@@@@@. .@@@@@. .@@..@..@@. @@........@@ DC.W $01F0E,$0B9F3,$026C0,$03000 ; ..@@@@@@@.. @@@@@@@@@@@ @@@@@@@ @@@@@@@@@@@ @@........@@ DC.W $00E00,$080E0,$020C0,$03000 ; ...@@@@@... .@@@.@.@@@. .@@@@@. .@@..@..@@. @@........@@ DC.W $00403,$0E040,$0F8FF,$0F000 ; ....@@@.... .....@..... ..@@@.. .....@..... @@........@@ DC.W $00000,$00000,$00000,$00000 ; .....@..... ...@@@@@... ...@... ...@@@@@... @@@@@@@@@@@@ DC.W $00000,$00000,$00000,$00000 ; ........... ........... ....... ........... ............ fontLoc: ; The fontLoc information is used to "unpack" the fontData. Each DC.L $0000000B ; pair of words specifies how the characters are bit-packed. For DC.L $000B000B ; example, the first character starts at bit position 0x0000, and DC.L $00160007 ; is 0x000B (11) bits wide. The second character starts at bit DC.L $001D000B ; position 0x000B and is 0x000B bits wide, and so on. This tells DC.L $0028000C ; the font handler how to unpack the bits from the array. fontSpace: ; fontSpace array: Use a space this wide to contain this DC.W 000012,000012 ; character when it is printed. For reverse-path fonts DC.W 000008,000012,000013 ; these values would be small or negative. fontKern: ; fontKern array: Place a space this wide after the DC.W 000001,000001 ; corresponding character to separate it from the following DC.W 000001,000001,000001 ; character. For reverse-path fonts these values would be large ; negative numbers, approximately the width of the characters. fontEnd: END