honeylisp/game/defs.fnl

171 lines
4.3 KiB
Fennel

(local util (require :lib.util))
(local {: lo : hi : readjson} util)
(local lume (require :lib.lume))
(local asm (require :asm.asm))
(local VM (require :asm.vm))
(local tiles (require :game.tiles))
(local Prodos (require :asm.prodos))
(local prg (asm.new))
(local vm (VM.new prg {:org 0xc00}))
(Prodos.install-words vm)
(local org {
:boot vm.code
:code (prg:org 0x4000)
})
(local mapw 20)
(local maph 12)
(local mon {
:hexout :0xfdda
:putchar :0xfded
:bell :0xff3a
})
(local style {
:normal 0x80
:inverse 0x00
:flashing 0x40
})
(fn str-with-style [s stylebits]
(-> [(string.byte s 1 -1)]
(lume.map #(bit.bor (bit.band $1 0x3f) stylebits))
(-> (table.unpack) (string.char))))
(fn achar [c] (bit.bor (string.byte c) style.normal))
(fn astr [s ?style] (str-with-style s (or ?style style.normal)))
(fn rot8l [n] ; clears carry
(local block [:block [:clc]])
(for [_ 1 n] (table.insert block [:block [:asl :a] [:adc 0]]))
block)
; core graphics words needed for booting
(vm:def :hires
[:sta :0xc050]
[:sta :0xc057]
[:sta :0xc052]
[:sta :0xc054])
(vm:def :cleargfx
(vm:push 0x4000)
[:block :page
[:dec vm.TOPH :x]
[:lda 0]
[:block :start
[:sta [vm.TOP :x]]
[:inc vm.TOP :x]
[:bne :start]]
[:lda vm.TOPH :x]
[:cmp 0x20]
[:bne :page]]
(vm:drop))
; a handful of debugging words
(vm:def :.
[:lda vm.TOPH :x]
[:jsr mon.hexout]
[:lda vm.TOP :x]
[:jsr mon.hexout]
[:lda (achar " ")]
[:jsr mon.putchar]
(vm:drop))
(vm:def :stacklen
(vm:reserve)
[:txa] [:lsr :a] [:sta vm.TOP :x]
[:lda 0] [:sta vm.TOPH :x])
(vm:word :.s
:stacklen (prg:parse-addr vm.TOP) :swap
(vm:for :dup :get :. :inc :inc) :drop)
; input words
(vm:def :last-key ; -- key
(vm:reserve)
[:lda :0xc000]
[:and 0x7f]
[:sta vm.TOP :x]
[:lda 0]
[:sta vm.TOPH :x])
(vm:def :read-key ; -- key|0
[:block
(vm:reserve)
[:lda :0xc000]
[:bmi :key-pressed]
[:lda 0]
[:sta vm.TOP :x]
[:sta vm.TOPH :x]
(vm:ret)
:key-pressed
[:and 0x7f]
[:sta vm.TOP :x]
[:lda 0]
[:sta vm.TOPH :x]
[:sta :0xc010]])
; "random" numbers
; this is used only for cosmetic purposes and short noise generation, so we can get away
; with just including a short table of random digits rather than implementing our own
; pseudorandom number generator
(var randombytes "")
(for [i 0 0x40] (set randombytes (.. randombytes (string.char (math.random 0 255)))))
(vm.code:append :randombytes [:bytes randombytes])
(vm:var :irandom [:db 0])
(vm:word :rnd
:irandom :bget
:dup 1 :+ 0x3f :& :irandom :bset
:lit :randombytes :+ :bget)
; 20x12 means full map is 240 bytes - we have an extra 16 bytes at the end for metadata
(fn append-map [map org label]
(org:append
[:align 0x100] label
[:bytes (map.map:fromhex)]
[:db (length map.objects)]
[:dw (tiles.encode-yx map.player)]
[:jmp (if (= (or map.tickword "") "") :next map.tickword)]
[:jmp (if (= (or map.moveword "") "") :move-noop map.moveword)]
[:jmp (if (= (or map.loadword "") "") :next map.loadword)]))
(vm.code:append :map-ptr [:db 0] :map-page [:db 0])
(vm:word :map :lit :map-ptr :get)
(vm:word :entity-count :map 240 :+ :bget)
(vm:word :map-player-yx :map 241 :+ :get)
(vm:word :map-specific-tick :map 243 :+ :execute)
(vm:word :map-specific-move :map 246 :+ :execute)
(vm:word :map-specific-load :map 249 :+ :execute)
(fn deflevel [mapfile label]
(local level prg) ; todo: (asm.new prg) - if we want to load levels as an overlay
(local org level.vm.code) ; (level:org org.level.org) - if we want to give level data a stable loxation
(local map (readjson mapfile))
(local entity (require :game.entity))
(append-map map org label)
(entity.append-from-map map org label)
(set level.vm.code org)
level)
(fn say-runon [portrait ...]
(local result [:vm (.. :draw-p portrait)])
(local lines [...])
(local ilineOffset (if (< (length lines) 4) 1 0))
(each [iline line (ipairs lines)]
(table.insert result [:vm (vm:str line) (.. :draw-text (+ iline ilineOffset))]))
result)
(fn say [portrait ...]
(local result (say-runon portrait ...))
(table.insert result :dismiss-dialog)
result)
(local tilelist (tiles.loadgfx tiles.fn-tiles))
(fn itile [label] (tiles.find-itile tilelist label))
(set vm.code org.code)
{: vm : prg : mapw : maph : mon : org : achar : astr : style : rot8l : deflevel : say : say-runon : itile : tilelist}