98 lines
2.3 KiB
Lua
98 lines
2.3 KiB
Lua
pico-8 cartridge // http://www.pico-8.com
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version 42
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__lua__
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--magnitest.p8
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--accuracy and perf tests for
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--vector calculation logic
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-- profiler says 67 cycles
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-- 39 lua, 28 system
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function bbs28999alg(dx, dy)
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local d = max(abs(dx),abs(dy))
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local n = min(abs(dx),abs(dy)) / d
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return sqrt(n*n + 1) * d
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end
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-- profiler says 56 cycles
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-- 24 lua, 32 system
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function bbs28999algopt(dx, dy)
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local d,n=abs(dx),abs(dy)
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if (d<n) d,n=n,d
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n/=d
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return (n*n + 1)^0.5 * d
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end
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-- profiler says 18 cycles
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-- 18 lua, 0 system
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function trigalg(dx, dy)
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local s = sin(atan2(dx,dy))
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if (s==0) return abs(dx)
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return abs(dy/s)
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end
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-->8
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function _init()
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gdx,gdy=0,0
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acc=1
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magnitude = 1
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tresult=0
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bresult=0
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delta=0
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end
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function _update60()
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if (btn(0)) gdx -= acc
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if (btn(1)) gdx += acc
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if (btn(2)) gdy -= acc
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if (btn(3)) gdy += acc
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if (btn(4) and btn(5)) gdx,gdy=0,0
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if btn == 0 or btn(4) then
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acc = 1
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elseif btn(5) then
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acc *= 1.1
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else
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acc *= 1.02
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end
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local a,b=abs(gdx),abs(gdy)
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if (b>a) a,b=b,a
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magnitude = 1
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while magnitude < a do
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magnitude *= 2
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end
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bresult=bbs28999algopt(gdx,gdy)
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tresult=trigalg(gdx,gdy)
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delta=tresult-bresult
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end
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cols = {
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6,7,
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[4]=10,
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[8]=9,
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[16]=4,
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[32]=14,
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[64]=15,
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[128]=11,
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[256]=12,
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[512]=13,
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[1024]=8,
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}
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function _draw()
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cls()
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camera(-63,-63)
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line(0,0,gdx/magnitude,gdy/magnitude,cols[magnitude] or 2)
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rectfill(0,0,gdx/magnitude,0,5)
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rectfill(0,0,0,gdy/magnitude,5)
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print("x: "..tostr(gdx).." y: "..tostr(gdy).."\nbase: "..tostr(bresult).."\ntrig: "..tostr(tresult).."\n\ndiff: "..tostr(delta),-63,-63)
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end
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__gfx__
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00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
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00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
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00700700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
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00077000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
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00077000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
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00700700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
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