diff options
| -rw-r--r-- | docs/gpu.txt | 23 | ||||
| -rw-r--r-- | gpu.lua | 100 |
2 files changed, 119 insertions, 4 deletions
diff --git a/docs/gpu.txt b/docs/gpu.txt index a2ea3c7..80c8852 100644 --- a/docs/gpu.txt +++ b/docs/gpu.txt @@ -147,3 +147,26 @@ y1 [integer 1-64]: The Y position of the start of the line. y2 [integer 1-64]: The Y position of the end of the line. color [hex color, default "000000"]: The nominal color of the line (may not be the color of every pixel, see the "antialias" setting) antialias [boolean, default false]: Whether to apply a (very) crude smoothing algorithm to the line to reduce jagged edges at the expense of making the line slightly blurry. + +Command: sendpacked +------------------- + +Converts the image in a buffer into a string representation that can be loaded again later with the "loadpacked" command. +The result uses 4 bytes per pixel and consists entirely of printable characters (A-Z, a-z, 0-9, +, and /). + +Parameters: +buffer [integer 0-7]: The buffer to convert. +channel [string]: The digilines channel to send the packed image on. + +Command: loadpacked +------------------- + +Load a string representation of an image (created by the "sendpacked" command) back into a buffer. + +Parameters: +buffer [integer 0-7]: The buffer to load the image into. +x [integer 1-64]: The X position of the left side of the image. +y [integer 1-64]: The Y position of the top of the image. +xsize [integer 1-64]: The width of the image. Must be the same as the original image or the image will be severely distorted. +ysize [integer 1-64]: The height of the image. Should be the same as the original image. +data [string]: The packed image to load. @@ -1,21 +1,70 @@ local font = dofile(minetest.get_modpath("digistuff")..DIR_DELIM.."gpu-font.lua") -local function explodebits(input) +local function explodebits(input,count) local output = {} - for i=0,7,1 do + if not count then count = 8 end + for i=0,count-1,1 do output[i] = input%(2^(i+1)) >= 2^i end return output end -local function implodebits(input) +local function implodebits(input,count) local output = 0 - for i=0,7,1 do + if not count then count = 8 end + for i=0,count-1,1 do output = output + (input[i] and 2^i or 0) end return output end +local packtable = {} +local unpacktable = {} +for i=0,25,1 do + packtable[i] = string.char(i+65) + packtable[i+26] = string.char(i+97) + unpacktable[string.char(i+65)] = i + unpacktable[string.char(i+97)] = i+26 +end +for i=0,9,1 do + packtable[i+52] = tostring(i) + unpacktable[tostring(i)] = i+52 +end +packtable[62] = "+" +packtable[63] = "/" +unpacktable["+"] = 62 +unpacktable["/"] = 63 + +local function packpixel(pixel) + pixel = tonumber(pixel,16) + if not pixel then return "AAAA" end + local bits = explodebits(pixel,24) + local block1 = {} + local block2 = {} + local block3 = {} + local block4 = {} + for i=0,5,1 do + block1[i] = bits[i] + block2[i] = bits[i+6] + block3[i] = bits[i+12] + block4[i] = bits[i+18] + end + local char1 = packtable[implodebits(block1,6)] or "A" + local char2 = packtable[implodebits(block2,6)] or "A" + local char3 = packtable[implodebits(block3,6)] or "A" + local char4 = packtable[implodebits(block4,6)] or "A" + return char1..char2..char3..char4 +end + +local function unpackpixel(pack) + local block1 = unpacktable[pack:sub(1,1)] or 0 + local block2 = unpacktable[pack:sub(2,2)] or 0 + local block3 = unpacktable[pack:sub(3,3)] or 0 + local block4 = unpacktable[pack:sub(4,4)] or 0 + local out = block1+(2^6*block2)+(2^12*block3)+(2^18*block4) + return string.format("%06X",out) +end + local function rgbtohsv(r,g,b) r = r/255 g = g/255 @@ -416,6 +465,49 @@ local function runcommand(pos,meta,command) end end meta:set_string("buffer"..bufnum,minetest.serialize(buffer)) + elseif command.command == "sendpacked" then + if type(command.buffer) ~= "number" or type(command.channel) ~= "string" then return end + local bufnum = math.floor(command.buffer) + if bufnum < 0 or bufnum > 7 then return end + local buffer = meta:get_string("buffer"..bufnum) + if string.len(buffer) == 0 then return end + buffer = minetest.deserialize(buffer) + if type(buffer) == "table" then + local packeddata = "" + for y=1,buffer.ysize,1 do + for x=1,buffer.xsize,1 do + packeddata = packeddata..packpixel(buffer[y][x]) + end + end + digiline:receptor_send(pos,digiline.rules.default,command.channel,packeddata) + end + elseif command.command == "loadpacked" then + if type(command.buffer) ~= "number" or type(command.data) ~= "string" then return end + if type(command.x) ~= "number" or type(command.y) ~= "number" or type(command.xsize) ~= "number" or type(command.ysize) ~= "number" then return end + command.x = math.floor(command.x) + command.y = math.floor(command.y) + command.xsize = math.floor(command.xsize) + command.ysize = math.floor(command.ysize) + if command.x < 1 or command.y < 1 or command.xsize < 1 or command.ysize < 1 then return end + local bufnum = math.floor(command.buffer) + if bufnum < 0 or bufnum > 7 then return end + local buffer = meta:get_string("buffer"..bufnum) + if string.len(buffer) == 0 then return end + buffer = minetest.deserialize(buffer) + if type(buffer) == "table" then + if command.x + command.xsize - 1 > buffer.xsize then return end + if command.y + command.ysize - 1 > buffer.ysize then return end + for y=0,command.ysize-1,1 do + local dsty = command.y+y + for x=0,command.xsize-1,1 do + local dstx = command.x+x + local packidx = (y*command.xsize+x)*4+1 + local packeddata = string.sub(command.data,packidx,packidx+3) + buffer[dsty][dstx] = unpackpixel(packeddata) + end + end + meta:set_string("buffer"..bufnum,minetest.serialize(buffer)) + end end end |