Added parsing function into CCPI

ccpi.lua

@@ -64,10 +64,7 @@ decoders[1] = function(image, fp)
     return true
 end
 
-local function load(path)
+local function parse(fp)
-    local fp, err = io.open(path, "rb")
-    if not fp then return nil, err end
-
     local res
     local image = { w = 0, h = 0, scale = 1.0, palette = {}, lines = {} }
 
@@ -86,11 +83,19 @@ local function load(path)
         return nil, "Invalid header: expected CCPI got " .. magic
     end
 
-    fp:close()
     if not res then return false, err end
     return image
 end
 
+local function load(path)
+    local fp, err = io.open(path, "rb")
+    if not fp then return nil, err end
+    local img
+    img, err = parse(fp)
+    fp:close()
+    return img, err
+end
+
 local function draw(img, ox, oy, monitor)
     -- todo: add expect()
     local t = monitor or term.current()
@@ -101,7 +106,7 @@ local function draw(img, ox, oy, monitor)
         return nil, "setPaletteColor is not supported on this term"
     end
 
-    if not t.setTextScale then
+    if not t.setTextScale and img.scale != 1 then
         return nil, "setTextScale is not supported on this term"
     end
 
@@ -109,7 +114,9 @@ local function draw(img, ox, oy, monitor)
         t.setPaletteColor(bit.blshift(1, i - 1), img.palette[i])
     end
 
+    if img.scale != 1 then
         t.setTextScale(img.scale)
+    end
 
     for y = 1, img.h do
         t.setCursorPos(ox, oy + y - 1)
@@ -119,5 +126,6 @@ end
 
 return {
     load = load,
-    draw = draw
+    draw = draw,
+    parse = parse
 }