47 lines
1.1 KiB
Forth
47 lines
1.1 KiB
Forth
# Cursor-based motions.
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#
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# To build a disk image:
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# ./translate ex7.mu # emits disk.img
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# To run:
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# qemu-system-i386 disk.img
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# Or:
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# bochs -f baremetal/boot.bochsrc # boot.bochsrc loads disk.img
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#
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# Expected output: an interactive game a bit like "snakes". Try pressing h, j,
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# k, l.
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fn main {
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var space/eax: grapheme <- copy 0x20
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set-cursor-position 0/screen, 0, 0
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{
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draw-cursor 0/screen, space
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var key/eax: byte <- read-key 0/keyboard
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{
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compare key, 0x68/h
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break-if-!=
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draw-code-point-at-cursor 0/screen, 0x2d/dash, 0x31/fg, 0/bg
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move-cursor-left 0
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}
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{
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compare key, 0x6a/j
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break-if-!=
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draw-code-point-at-cursor 0/screen, 0x7c/vertical-bar, 0x31/fg, 0/bg
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move-cursor-down 0
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}
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{
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compare key, 0x6b/k
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break-if-!=
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draw-code-point-at-cursor 0/screen, 0x7c/vertical-bar, 0x31/fg, 0/bg
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move-cursor-up 0
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}
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{
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compare key, 0x6c/l
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break-if-!=
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var g/eax: code-point <- copy 0x2d/dash
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draw-code-point-at-cursor 0/screen, 0x2d/dash, 0x31/fg, 0/bg
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move-cursor-right 0
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}
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loop
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}
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}
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