-- -- ga Intermediate Graphic Language for barcode drawing -- Copyright (C) 2020 Roberto Giacomelli -- -- Basic driver interface -- drawing elementary vector shape -- All dimensions are in scaled point (sp) local Driver = { _VERSION = "Driver v0.0.9", _NAME = "Driver", _DESCRIPTION = "Driver for ga graphic assembler stream", } Driver.__index = Driver Driver._drv_instance = {} -- driver instances repository -- driver_type/submodule name Driver._drv_available_drv = { -- lowercase keys please native = "lib-driver.brcd-drv-pdfliteral", -- only LuaTeX driver svg = "lib-driver.brcd-drv-svg", } function Driver:_get_driver(id_drv) --> object, err if type(id_drv) ~= "string" then return nil, "[ArgErr] 'id_drv' is not a string" end if not self._drv_available_drv[id_drv] then return nil, "[ArgErr] driver '"..id_drv.."' not found" end local t_drv = self._drv_instance if t_drv[id_drv] then -- is the repo already loaded? return t_drv[id_drv], nil else -- loading driver local module = self._drv_available_drv[id_drv] local channel = require(module) t_drv[id_drv] = channel return channel, nil end end function Driver:_new_state() --> a new state return { line_width = 65781.76, -- line width 1bp (in scaled point sp) line_cap = 0, -- line cap style line_join = 0, -- line join style gtext = false, -- text group off bb_on = true, -- bounding box checking activation bb_x1 = nil, -- bounding box coordinates in sp (nil means no data) bb_y1 = nil, bb_x2 = nil, bb_y2 = nil, mm = 186467.98110236, -- conversion factor sp -> mm (millimeter) bp = 65781.76, -- conversion factor sp -> bp (big point) } end function Driver:_ga_process(drv, ga, st, bf, xt) local op_fn = self._opcode_v001 local pc = 1 -- program counter local data = ga._data while data[pc] do -- stream processing local opcode = data[pc] local fn = assert(op_fn[opcode], "[InternalErr] unimpl opcode ".. opcode) pc = fn(drv, st, pc + 1, data, bf, xt) end end -- save graphic data in an external file with the 'id_drv' format -- id_drv: specific driver output -- ga: ga object -- filename: file name -- ext: file extension (optional) function Driver:save(id_drv, ga, filename, ext) --> ok, err -- retrive the output library local drv, err = self:_get_driver(id_drv) if err then return false, err end -- init local state = self:_new_state() local buf, txt_buf = drv.init_buffer(state) -- a new buffer and text_buffer -- processing self:_ga_process(drv, ga, state, buf, txt_buf) -- buffer finalizing drv.close_buffer(state, buf, txt_buf) -- finalize the istruction -- file saving local sep = drv.buf_sep ext = ext or drv.ext local fn = io.open(filename.."."..ext, "w") -- output the file fn:write(table.concat(buf, sep)) -- concat the buffer fn:close() return true, nil end -- insert a ga drawing in a TeX box -- PDFnative only function function Driver:ga_to_hbox(ga, boxname) --> ok, err -- retrive the output library local id_drv = "native" local drv, err = self:_get_driver(id_drv) if err then return false, err end -- init process local state = self:_new_state() local buf, txt_buf = drv.init_buffer(state) -- a new buffer and text_buffer -- processing self:_ga_process(drv, ga, state, buf, txt_buf) -- finalizing drv.close_buffer(state, buf, txt_buf) -- finalize the istruction sequence -- build hbox local ok, err = drv.hboxcreate(boxname, state, buf, txt_buf) return ok, err end -- operational functions -- _op_v001 corresponds to the version 1 of ga graphic assembler specification. -- The table indexes every opcode to a function that takes these arguments and -- return the updated program counter pointed to the next operation: -- fn: format specific driver library -- st: state -- pc: program counter -- ga: read only ga stream -- bf: the output buffer -- xt: the output text object buffer Driver._opcode_v001 = { [1] = function (drv, st, pc, ga, bf, xt) -- 1 ; set line width local w = ga[pc] st.line_width = w if not drv.append_001 then error("[InternalErr] unimplemented opcode 1 for "..drv._NAME) end drv.append_001(st, bf, xt, w) return pc + 1 end, [2] = function (drv, st, pc, ga, bf, xt) -- 2 ; set line cap style local style = ga[pc] st.line_cap = style if not drv.append_002 then error("[InternalErr] unimplemented opcode 2 for "..drv._NAME) end drv.append_002(st, bf, xt, style) return pc + 1 end, [3] = function (drv, st, pc, ga, bf, xt) -- 3 ; set line join style local join = ga[pc] if not drv.append_003 then error("[InternalErr] unimplemented opcode 3 for "..drv._NAME) end drv.append_003(st, bf, xt, join) return pc + 1 end, [30] = function (drv, st, pc, ga, bf, xt) -- start_bbox_group assert(st.bb_on) st.bb_on = false return pc end, [31] = function (drv, st, pc, ga, bf, xt) -- end_bbox_group assert(st.bb_on == false) st.bb_on = true local x1 = ga[pc]; pc = pc + 1 local y1 = ga[pc]; pc = pc + 1 local x2 = ga[pc]; pc = pc + 1 local y2 = ga[pc]; pc = pc + 1 if st.bb_x1 == nil then st.bb_x1 = x1 st.bb_y1 = y1 st.bb_x2 = x2 st.bb_y2 = y2 else if x1 < st.bb_x1 then st.bb_x1 = x1 end if x2 > st.bb_x2 then st.bb_x2 = x2 end if y1 < st.bb_y1 then st.bb_y1 = y1 end if y2 > st.bb_y2 then st.bb_y2 = y2 end end return pc end, -- draw an horizontal line -- 33 [33] = function (drv, st, pc, ga, bf, xt) local x1 = ga[pc]; pc = pc + 1 local x2 = ga[pc]; pc = pc + 1 local y = ga[pc]; pc = pc + 1 if st.bb_on then -- eventually update bbox local hw = st.line_width/2 local by1 = y - hw local by2 = y + hw if st.bb_x1 == nil then st.bb_x1 = x1 st.bb_x2 = x2 st.bb_y1 = by1 st.bb_y2 = by2 else if x1 < st.bb_x1 then st.bb_x1 = x1 end if x2 > st.bb_x2 then st.bb_x2 = x2 end if by1 < st.bb_y1 then st.bb_y1 = by1 end if by2 > st.bb_y2 then st.bb_y2 = by2 end end end if not drv.append_033 then error("[InternalErr] unimplemented opcode 33 for "..drv._NAME) end drv.append_033(st, bf, xt, x1, x2, y) return pc end, -- draw a vertical line [34] = function (drv, st, pc, ga, bf, xt) -- 34 local y1 = ga[pc]; pc = pc + 1 local y2 = ga[pc]; pc = pc + 1 local x = ga[pc]; pc = pc + 1 if st.bb_on then -- eventually update the figure bounding box local hw = st.line_width/2 local bx1 = x - hw local bx2 = x + hw if st.bb_x1 == nil then st.bb_x1 = bx1 st.bb_x2 = bx2 st.bb_y1 = y1 st.bb_y2 = y2 else if bx1 < st.bb_x1 then st.bb_x1 = bx1 end if bx2 > st.bb_x2 then st.bb_x2 = bx2 end if y1 < st.bb_y1 then st.bb_y1 = y1 end if y2 > st.bb_y2 then st.bb_y2 = y2 end end end if not drv.append_034 then error("[InternalErr] unimplemented opcode 34 for "..drv._NAME) end drv.append_034(st, bf, xt, y1, y2, x) return pc end, -- draw a group of vertical lines (vbar) -- 36 [36] = function(drv, st, pc, ga, bf, xt) -- vbar local y1 = ga[pc]; pc = pc + 1 local y2 = ga[pc]; pc = pc + 1 local nbar = ga[pc]; pc = pc + 1 assert(nbar > 0) local h = y2 - y1 -- height common to every rectangle assert(h > 0) local pc_next = pc + 2 * nbar if drv.append_036_start then drv.append_036_start(st, bf, xt, nbar, y1, y2) end local bx1, bx2 for i = pc, pc_next - 1, 2 do -- reading coordinates local x = assert(ga[i], "[InternalErr] ga prematurely reached the end") local w = assert(ga[i+1], "[InternalErr] ga prematurely reached the end") drv.append_036_bar(st, bf, xt, x, w, y1, y2) -- check the bounding box only if the corresponding flag is true local x1 = x - w/2 local x2 = x + w/2 if st.bb_on then if bx1 == nil then bx1 = x1 bx2 = x2 else if x1 < bx1 then bx1 = x1 end if x2 > bx2 then bx2 = x2 end end end end if drv.append_036_stop then drv.append_036_stop(st, bf, xt, nbar, y1, y2) end if st.bb_on then -- eventually update bbox if st.bb_x1 == nil then st.bb_x1 = bx1 st.bb_x2 = bx2 st.bb_y1 = y1 st.bb_y2 = y2 else if bx1 < st.bb_x1 then st.bb_x1 = bx1 end if bx2 > st.bb_x2 then st.bb_x2 = bx2 end if y1 < st.bb_y1 then st.bb_y1 = y1 end if y2 > st.bb_y2 then st.bb_y2 = y2 end end end return pc_next end, -- draw a rectangle -- 48 [48] = function(drv, st, pc, ga, bf, xt) local x1 = ga[pc]; pc = pc + 1 local y1 = ga[pc]; pc = pc + 1 local x2 = ga[pc]; pc = pc + 1 local y2 = ga[pc]; pc = pc + 1 -- check the bounding box only if the flag is true if st.bb_on then local hw = st.line_width/2 local bx1, bx2 = x1 - hw, x2 + hw local by1, by2 = y1 - hw, y2 + hw if st.bb_x1 == nil then st.bb_x1 = bx1 st.bb_x2 = bx2 st.bb_y1 = by1 st.bb_y2 = by2 else if bx1 < st.bb_x1 then st.bb_x1 = bx1 end if bx2 > st.bb_x2 then st.bb_x2 = bx2 end if by1 < st.bb_y1 then st.bb_y1 = by1 end if by2 > st.bb_y2 then st.bb_y2 = by2 end end end if not drv.append_048 then error("[InternalErr] unimplemented opcode 48 for "..drv._NAME) end drv.append_048(st, bf, xt, x1, y1, x2, y2) return pc end, -- text [130] = function(drv, st, pc, ga, bf, xt) -- text: ax ay xpos ypos string local ax = ga[pc]; pc = pc + 1 local ay = ga[pc]; pc = pc + 1 local xpos = ga[pc]; pc = pc + 1 local ypos = ga[pc]; pc = pc + 1 assert(ga[pc] ~= 0, "[InternalErr] empty chars sequence") while ga[pc] ~= 0 do local c = ga[pc]; pc = pc + 1 drv.append_130_char(st, bf, xt, c) end local x1, y1, x2, y2 = drv.append_130_stop(st, bf, xt, xpos, ypos, ax, ay) -- bounding box checking if st.bb_on then if st.bb_x1 == nil then st.bb_x1 = x1 st.bb_x2 = x2 st.bb_y1 = y1 st.bb_y2 = y2 else if x1 < st.bb_x1 then st.bb_x1 = x1 end if x2 > st.bb_x2 then st.bb_x2 = x2 end if y1 < st.bb_y1 then st.bb_y1 = y1 end if y2 > st.bb_y2 then st.bb_y2 = y2 end end end return pc + 1 end, [131] = function(drv, st, pc, ga, bf, xt) -- text_xspaced x1 xgap ay ypos chars local x1 = ga[pc]; pc = pc + 1 local xgap = ga[pc]; pc = pc + 1 local ay = ga[pc]; pc = pc + 1 local ypos = ga[pc]; pc = pc + 1 assert(ga[pc] ~= 0, "[InternalErr] empty chars sequence") while ga[pc] ~= 0 do local c = ga[pc]; pc = pc + 1 drv.append_131_char(st, bf, xt, c, xgap) end local bx1, by1, bx2, by2 = drv.append_131_stop(st, bf, xt, x1, xgap, ypos, ay) -- bounding box checking if st.bb_on then -- eventually update bbox if st.bb_x1 == nil then st.bb_x1 = bx1 st.bb_x2 = bx2 st.bb_y1 = by1 -- no depth st.bb_y2 = by2 else if bx1 < st.bb_x1 then st.bb_x1 = bx1 end if bx2 > st.bb_x2 then st.bb_x2 = bx2 end if by1 < st.bb_y1 then st.bb_y1 = by1 end if by2 > st.bb_y2 then st.bb_y2 = by2 end end end return pc + 1 end, -- text_xwidth -- [132] = function (drv, st, pc, ga, bf, xt) local ay = ga[pc]; pc = pc + 1 -- y anchor local x1 = ga[pc]; pc = pc + 1 -- left limit local x2 = ga[pc]; pc = pc + 1 -- right limit assert (x1 ~= x2, "[InternalErr] x coordinate are equal") assert (x1 < x2, "[InternalErr] not ordered x1, x2 limits") local ypos = ga[pc]; pc = pc + 1 -- y coordinate of anchor point assert(ga[pc] ~= 0, "[InternalErr] empty chars sequence") while ga[pc] ~= 0 do local c = ga[pc]; pc = pc + 1 drv.append_132_char(st, bf, xt, c) end local bx1, by1, bx2, by2 = drv.append_132_stop(st, bf, xt, x1, x2, ypos, ay) -- bounding box checking if st.bb_on then -- eventually update bbox if st.bb_x1 == nil then st.bb_x1 = bx1 st.bb_x2 = bx2 st.bb_y1 = by1 -- no depth st.bb_y2 = by2 else if bx1 < st.bb_x1 then st.bb_x1 = bx1 end if bx2 > st.bb_x2 then st.bb_x2 = bx2 end if by1 < st.bb_y1 then st.bb_y1 = by1 end if by2 > st.bb_y2 then st.bb_y2 = by2 end end end return pc + 1 end, } return Driver