commit 2f38abe0d47aedccbe94ee626ed865c3adfa3d23
Author: Kistaro Windrider <kistaro@gmail.com>
Date:   Fri Aug 4 16:38:36 2023 -0700

    initial commit.

diff --git a/README.md b/README.md
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+# Kistaro's tic-80 compositor
+
+TIC-80 port of my Pico-8 compositor, including a lot of Pico-8 camera and clip behaviors that aren't available in TIC-80. 
diff --git a/kistaro-compositor.lua b/kistaro-compositor.lua
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+-- title:   kistaro-compositor
+-- author:  Kistaro Windrider (kistaro@gmail.com)
+-- desc:    Rendering compositor library. Includes Pico-8 camera features.
+-- site:    https://dragon.style/@kistaro
+-- license: MIT License
+-- version: 0.1
+-- script:  lua
+
+
+function BOOT()
+end
+
+function TIC()
+end
+
+--stdlib--
+
+-- generate standard "overlay"
+-- constructor for type tt.
+-- if more is defined, generated
+-- new calls more(ret) after ret is
+-- definitely not nil, before calling
+-- setmetatable. Use to initialize
+-- mutable items.
+function MkNew(tt, more)
+	local mt = {__index=tt}
+	-- check "more" only once ever
+	if more then
+	 tt.new = function(ret)
+		 ret = ret or {}
+			more(ret)
+			setmetatable(ret, mt)
+			return ret
+		end
+	else
+	 tt.new = function(ret)
+	 	ret = ret or {}
+	 	setmetatable(ret, mt)
+	  return ret
+		end
+	end
+end
+
+--Window compositor--
+
+CamCtl = {
+ XOff = 0,
+ YOff = 0,
+ XAbsClip = 0,
+ YAbsClip = 0,
+ W = 240,
+ H = 136,
+ OriginStack = {},
+ ClipStack = {},
+}
+
+-- Overwrite current camera origin.
+-- (0, 0) is now this pixel coordinate.
+function CamCtl:SetAbsOrigin(x, y)
+ self.XOff, self.YOff = x, y
+end
+
+-- Push current camera origin onto
+-- the history stack and set the
+-- new origin.
+function CamCtl:PushAbsOrigin(x, y)
+ table.insert(self.OriginStack, {self.XOff, self.YOff})
+ self.XOff, self.YOff = x, y
+end
+
+function CamCtl:SetRelOrigin(x, y)
+ self.XOff = self.XOff + x
+ self.YOff = self.Yoff + y
+end
+
+function CamCtl:PushRelOrigin(x, y)
+ table.insert(self.OriginStack, {self.XOff, self.YOff})
+ self.XOff = self.XOff + x
+ self.YOff = self.YOff + Y
+end
+
+function CamCtl:SetAbsCam(x, y)
+ self.XOff, self.YOff = -x, -y
+end
+
+function CamCtl:PushAbsCam(x, y)
+ table.insert(self.OriginStack, {self.XOff, self.YOff})
+ self.XOff, self.YOff = -x, -y
+end
+
+function CamCtl:SetRelCam(x, y)
+ self.XOff = self.XOff - x
+ self.YOff = self.YOff - y
+end
+
+function CamCtl:PushRelCam(x, y)
+ table.insert(self.OriginStack, {self.XOff, self.YOff})
+ self.XOff = self.XOff - x
+ self.YOff = self.YOff - y
+end 
+
+function CamCtl:PopOrigin()
+ if #self.OriginStack == 0 then
+  self.XOff, self.YOff = 0, 0
+  return
+ end
+ self.XOff, self.YOff = unpack(table.Remove(self.OriginStack))
+end
+CamCtl.PopCam = CamCtl.PopOrigin
+
+function CamCtl:SetNewClip(x, y, w, h)
+ if x then
+  self.XAbsClip = self.XOff + x
+  self.YAbsClip = self.YOff + y
+  self.W, self.H = w, h
+  clip(self.XAbsClip, self.YAbsClip, self.W, self.H)
+  return
+ end
+ self.XAbsClip, self.YAbsClip, self.W, self.H = 0,0,240,136
+ clip()
+end
+
+function CamCtl:PushNewClip(x, y, w, h)
+ table.insert(self.ClipStack, {self.XAbsClip, self.YAbsClip, self.W, self.H}
+ self:SetNewClip(x, y, w, h)
+end
+
+function CamCtl:SetReClip(x,y,w,h)
+ if not x then
+  return
+ end
+ 
+ x = x + self.XOff
+ local x2 = math.min(x + w, self.XAbsClip + self.W)
+ self.XAbsClip = math.max(x, self.XAbsClip)
+ self.W = max(0, x2 - self.XAbsClip)
+ 
+ y = y + self.YOff
+ local y2 = math.min(y+h, self.YAbsClip + self.H)
+ self.YAbsClip = math.max(y, self.YAbsClip)
+ self.H = max(0, y2 - self.YAbsClip)
+
+ clip(self.XAbsClip, self.YAbsClip, self.W, self.H)
+end
+
+function CamCtl:PushReClip(x,y,w,h)
+ table.insert(self.ClipStack, {self.XAbsClip, self.YAbsClip, self.W, self.H}
+ self.SetReClip(x,y,w,h)
+end
+
+function CamCtl:PopClip()
+ if #self.ClipStack == 0 then
+  self.XAbsClip, self.YAbsClip, self.W, self.H = 0,0,240,136
+  clip()
+  return
+ end
+ local x,y,w,h = unpack(table.remove(self.ClipStack)))
+ self.XAbsClip, self.YAbsClip, self.W, self.H = x,y,w,h
+ clip(x,y,w,h)
+end
+-- Install
+-- (swizzle all drawing functions!)
+
+function CamCtl:Install()
+ local adjust_leading_2 = {
+  "circ", "circb",
+  "elli", "ellib",
+  "pix",
+  "rect", "rectb",
+ }
+ for _, fn in ipairs(adjust_leading_2) do
+  local f_orig = _G[fn]
+  _G[fn] = function(x, y, ...)
+   return f_orig(x + self.XOff, y + self.YOff, ...)
+  end
+ end
+ 
+ local keep_first_adjust_2_opt = {
+  "spr", "font", "print"
+ }
+ for _, fn in ipairs(keep_first_adjust_2_opt) do
+  local f_orig = _G[fn]
+  _G[fn] = function(v, x, y, ...)
+   if x then
+    x = x + self.XOff
+   end
+   if y then
+    y = y + self.YOff
+   end
+   return f_orig(v, x, y, ...)
+  end
+ end
+
+ local tri_family = {"tri", "trib", "textri"}
+ 
+ for _, fn in ipairs(tri_family) do
+  local f_orig = _G[fn]
+  _G[fn] = function(x1, y1, x2, y2, x3, y3, ...)
+   return f_orig(
+    x1 + self.XOff, y1 + self.YOff,
+    x2 + self.XOff, y2 + self.YOff,
+    x3 + self.XOff, y3 + self.YOff,
+    ...
+   )
+  end
+ end
+ 
+ local map_orig = map
+ map = function(mx, my, w, h, sx, sy, ...)
+  XXX(kistaro): implement!
+  -- if called with no args, calculate new map
+  -- coordinates, clipping at 0, to respect
+  -- camera movement! this will require full tile
+  -- movement to be reflected in mx/my, w and h to
+  -- stay 30 x 17 unless they go to 31 x 18 for
+  -- partial tiles at edges, and sx and sy to become
+  -- offsets. If sx and sy are provided, do the
+  -- obvious thing instead, which is much easier.
+ end
+ 
+ local line_orig = line
+ line = function(x0, y0, x1, y1, color)
+  return line_orig(
+   x0 + self.XOff, y0 + self.YOff,
+   x1 + self.XOff, y1 + self.YOff,
+   color
+  )
+ end
+end
+-- <SPRITES>
+-- 000:0222220021111110212121102122211021121110211111100111110000000000
+-- 001:0bbbbb00b9999980b999b980b99bb980b9bbb980b99999800888880000000000
+-- 002:0555550056666670565566705655567056655670566666700777770000000000
+-- 003:0444440043333320433433204344432043434320433333200222220000000000
+-- 004:0ddddd00deeeeef0dededef0deedeef0dededef0deeeeef00fffff0000000000
+-- </SPRITES>
+
+-- <WAVES>
+-- 000:00000000ffffffff00000000ffffffff
+-- 001:0123456789abcdeffedcba9876543210
+-- 002:0123456789abcdef0123456789abcdef
+-- </WAVES>
+
+-- <SFX>
+-- 000:000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000304000000000
+-- </SFX>
+
+-- <TRACKS>
+-- 000:100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+-- </TRACKS>
+
+-- <PALETTE>
+-- 000:1a1c2c5d275db13e53ef7d57ffcd75a7f07038b76425717929366f3b5dc941a6f673eff7f4f4f4be69ce61309940205d
+-- </PALETTE>
+
diff --git a/kistaro-compositor.tic b/kistaro-compositor.tic
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