cc-stuff/ccpi.lua

77 lines
1.9 KiB
Lua

local colors_list = {
colors.white,
colors.orange,
colors.magenta,
colors.lightBlue,
colors.yellow,
colors.lime,
colors.pink,
colors.gray,
colors.lightGray,
colors.cyan,
colors.purple,
colors.blue,
colors.brown,
colors.green,
colors.red,
colors.black
}
local function load(path)
local image = { w = 0, h = 0, scale = 1.0, palette = {}, lines = {} }
local fp, err = io.open(path, "rb")
if not fp then return nil, err end
local magic = fp:read(4)
if magic ~= "CCPI" then
return nil, "Invalid header: expected CCPI got " .. magic
end
image.w, image.h = string.byte(fp:read(1)), string.byte(fp:read(1))
image.scale = 0.5 + string.byte(fp:read(1)) * 5 / 255
for i = 1, 16 do
image.palette[i] = bit32.lshift(string.byte(fp:read(1)), 16)
image.palette[i] = bit32.bor(image.palette[i], bit32.lshift(string.byte(fp:read(1)), 8))
image.palette[i] = bit32.bor(image.palette[i], string.byte(fp:read(1)))
end
for y = 1, image.h do
local line = { s = "", bg = "", fg = "" }
for x = 1, image.w do
line.s = line.s .. fp:read(1)
local color = string.byte(fp:read(1))
line.bg = line.bg .. string.format("%x", bit32.band(0xF, color))
line.fg = line.fg .. string.format("%x", bit32.band(0xF, bit32.rshift(color, 4)))
end
table.insert(image.lines, line)
end
fp:close()
return image
end
local function draw(img, ox, oy, monitor)
local t = monitor or term.current()
ox = ox or 1
oy = oy or 1
for i = 1, 16 do
t.setPaletteColor(colors_list[i], img.palette[i])
end
t.setTextScale(img.scale)
for y = 1, img.h do
t.setCursorPos(ox, oy + y - 1)
t.blit(img.lines[y].s, img.lines[y].fg, img.lines[y].bg)
end
end
return {
load = load,
draw = draw
}