commit 3baad0adc1e8bbe62bae5b480520eb46ee023dce
parent 7132197ba53b9752dd5d060441038b0c31c89278
Author: Andrew Alderwick <andrew@alderwick.co.uk>
Date: Mon, 17 May 2021 07:44:50 +0100
Added proportional font example
Diffstat:
1 file changed, 121 insertions(+), 0 deletions(-)
diff --git a/projects/examples/gui/proportional-font.usm b/projects/examples/gui/proportional-font.usm
@@ -0,0 +1,121 @@
+( GUI Proportional font )
+
+( devices )
+
+|00 @System [ &vector $2 &pad $6 &r $2 &g $2 &b $2 ]
+|20 @Screen [ &vector $2 &width $2 &height $2 &pad $2 &x $2 &y $2 &addr $2 &color $1 ]
+
+( variables )
+
+|0000
+
+( program )
+
+|0100
+
+ ( theme ) #0f9f .System/r DEO2 #0f3f .System/g DEO2 #0f30 .System/b DEO2
+
+ #0000 ;draw JSR2
+ #0001 ;draw JSR2
+ #0002 ;draw JSR2
+
+BRK
+
+@draw ( extra-spacing* -- )
+ STH2
+ ;text
+ &loop
+ LDAk
+ DUP #00 EQU ,&end JCN
+ DUP #0a EQU ,&linefeed JCN
+ #00 #0005 SFT2 ;font ADD2
+ DUP2 .Screen/addr DEO2
+ #29 .Screen/color DEO
+ ,get-x-advance JSR .Screen/x DEI2 ADD2 STH2kr ADD2 .Screen/x DEO2
+ &next
+ #0001 ADD2
+ ,&loop JMP
+
+ &linefeed
+ POP
+ #0000 .Screen/x DEO2
+ #0008 .Screen/y DEI2 ADD2 STH2kr ADD2 .Screen/y DEO2
+ ,&next JMP
+
+ &end
+ POP POP2 POP2r
+ JMP2r
+
+@get-x-advance ( font-char-addr* -- advance* )
+ ( Save two 00 bytes for later use )
+ #0000 SWP2
+ ( First, load the eight bytes that make up the character )
+ LDA2k SWP2 #0002 ADD2
+ LDA2k SWP2 #0002 ADD2
+ LDA2k SWP2 #0002 ADD2
+ LDA2
+ ( OR all the bytes together, so we know which columns contain filled pixels )
+ ORA2 ORA2 ORA2 ORA
+ ( Find the lowest set bit (using one of the 00 bytes at the top, but not consuming it) )
+ SUBk AND
+ ( Convert the nine possible values (00-80) into an offset into the magic table (00-08). )
+ ( They get jumbled up with these two operations, but each possible value remains unique )
+ #a3 MUL #16 DIV
+ ( Load the byte from the magic table, return a short (consuming/returning the 00 bytes at the top) )
+ ;&magic ADD2 LDA
+ JMP2r
+ ( The magic table performs the last bit of arithmetic we want:
+ * the advance in x should be one more than the number of columns with filled pixels,
+ * with a maximum of 8, and
+ * a minimum of 3. )
+ &magic
+ 03 ( lowest set bit is 00, 0 columns wide )
+ 06 ( lowest set bit is 08, 5 columns wide )
+ 05 ( lowest set bit is 10, 4 columns wide )
+ 08 ( lowest set bit is 02, 7 columns wide )
+ 04 ( lowest set bit is 20, 3 columns wide )
+ 03 ( lowest set bit is 80, 1 column wide )
+ 07 ( lowest set bit is 04, 6 columns wide )
+ 08 ( lowest set bit is 01, 8 columns wide )
+ 03 ( lowest set bit is 40, 2 columns wide )
+
+@font ( spectrum-zx font, with each character moved to be flush left in its cell )
+[
+ 0000 0000 0000 0000 0000 4800 fc78 0000 0000 4800 7884 0000 0000 d8f8 f870 2000
+ 0020 70f8 f870 2000 0070 70f8 d820 7000 0020 70f8 f820 7000 0000 00c0 c000 0000
+ 00fc 8484 8484 fc00 0000 6090 9060 0000 0030 4884 8448 3000 003c 0c74 9490 6000
+ 0070 88d8 20f8 2000 0030 2020 20e0 e000 007c 4444 44cc cc00 0000 2088 0088 2000
+ 0000 80c0 e0c0 8000 0000 2060 e060 2000 0040 e000 00e0 4000 00a0 a0a0 a000 a000
+ 007c 9494 7414 1400 0018 608c c418 6000 0000 0000 0000 ffff 0040 e000 e040 00e0
+ 0020 70a8 2020 2000 0020 2020 a870 2000 0000 1008 fc08 1000 0000 2040 fc40 2000
+ 0000 8080 fc00 0000 0000 0048 cc48 0000 0000 2070 f800 0000 0000 00f8 7020 0000
+ 0000 0000 0000 0000 0080 8080 8000 8000 00a0 a000 0000 0000 0048 fc48 48fc 4800
+ 0020 78a0 7028 f020 0084 0810 2040 8400 0060 9064 9888 7400 0040 8000 0000 0000
+ 0040 8080 8080 4000 0080 4040 4040 8000 0000 5020 f820 5000 0000 2020 f820 2000
+ 0000 0000 0040 4080 0000 0000 f000 0000 0000 0000 0000 8000 0000 0810 2040 8000
+ 0078 8c94 a4c4 7800 0060 a020 2020 f800 0078 8404 7880 fc00 0078 8438 0484 7800
+ 0010 3050 90fc 1000 00fc 80f8 0484 7800 0078 80f8 8484 7800 00fc 0408 1020 2000
+ 0078 8478 8484 7800 0078 8484 7c04 7800 0000 0080 0000 8000 0000 4000 0040 4080
+ 0000 2040 8040 2000 0000 00f8 00f8 0000 0000 8040 2040 8000 0078 8404 1800 1000
+ 0078 84b4 a884 7800 0030 4884 fc84 8400 00f8 84f8 8484 f800 0078 8480 8084 7800
+ 00f0 8884 8488 f000 00fc 80f8 8080 fc00 007c 8080 f880 8000 0078 8480 9c84 7800
+ 0084 84fc 8484 8400 00f8 2020 2020 f800 0004 0404 8484 7800 0088 90e0 9088 8400
+ 0080 8080 8080 fc00 0084 ccb4 8484 8400 0084 c4a4 948c 8400 0078 8484 8484 7800
+ 00f8 8484 f880 8000 0078 8484 a494 7800 00f8 8484 f888 8400 0078 8078 0484 7800
+ 00fe 1010 1010 1000 0084 8484 8484 7800 0084 8484 8448 3000 0084 8484 b4cc 8400
+ 0084 4830 3048 8400 0082 4428 1010 1000 00fc 0810 2040 fc00 00c0 8080 8080 c000
+ 0080 4020 1008 0400 00c0 4040 4040 c000 0020 5088 0000 0000 0000 0000 0000 fc00
+ 0080 4000 0000 0000 0000 7008 7888 7800 0080 80f0 8888 f000 0000 7880 8080 7800
+ 0008 0878 8888 7800 0000 7088 f080 7800 0060 80e0 8080 8000 0000 7088 8878 0870
+ 0080 80b0 c888 8800 0040 00c0 4040 2000 0010 0010 1010 9060 0080 90a0 c0a0 9000
+ 0080 8080 8080 6000 0000 d0a8 a8a8 a800 0000 b0c8 8888 8800 0000 7088 8888 7000
+ 0000 f088 88f0 8080 0000 7888 8878 080c 0000 b0c0 8080 8000 0000 7080 7008 f000
+ 0040 40f0 4040 3000 0000 8888 8888 7000 0000 8888 5050 2000 0000 88a8 a8a8 5000
+ 0000 8850 2050 8800 0000 8888 8878 0870 0000 f810 2040 f800 0060 4080 8040 6000
+ 0080 8080 8080 8000 00c0 4020 2040 c000 0000 0064 9800 0000 3c42 99a1 a199 423c
+]
+
+@text "Are 20 "proportional 20 "fonts 20 "a 20 "good 20 "idea? 0a 0a
+ "The 20 "jury 20 "is 20 "still 20 "out, 20 "but 20 "one 20 "thing 20 "is 20 "certain: 0a
+ "it 20 "is 20 "possible 20 "to 20 "print 20 "with 20 "these 20 "fonts 20 "in 20 "Uxn. 0a 0a 0a 00
+
