textgpu mostly works now

src/lua/core/textgpu.lua

@@ -45,11 +45,16 @@ local fg = 256
 local bg = 1
 local w, h = 1, 1
 
-local unsub
-local function set(x, y, text, f, b)
+local unsub, fullRefresh
+local function set(x, y, text, f, b, safe)
   if x > w or x < 1 or y > h or y < 1 or not tbuffer[y] then
+    if safe then
+      return
+    else
       error("index out of bounds: " .. y, 3)
     end
+  end
+  if not text then return end
   f = f or fg
   b = b or bg
   local len = utf8.len(text)
@@ -62,6 +67,8 @@ local function set(x, y, text, f, b)
     fbuffer[y] = fbuffer[y]:sub(1, x - 1) ..
       f .. fbuffer[y]:sub(x + len)
   else
+    local F = mapping[f]
+    write("\27[38;2;", F&0xFF0000>>16, ";", F&0x00FF00>>8, ";", F&0x0000FF, "m")
     fbuffer[y] = fbuffer[y]:sub(1, x - 1) ..
      string.rep(string.char(f - 1), len) .. fbuffer[y]:sub(x + len)
   end
@@ -69,16 +76,16 @@ local function set(x, y, text, f, b)
     bbuffer[y] = bbuffer[y]:sub(1, x - 1) ..
       b .. bbuffer[y]:sub(x + len)
   else
-    bbuffer[y] = fbuffer[y]:sub(1, x - 1) ..
+    local B = mapping[b]
+    write("\27[48;2;", B&0xFF0000>>16, ";", B&0x00FF00>>8, ";", B&0x0000FF, "m")
+    bbuffer[y] = bbuffer[y]:sub(1, x - 1) ..
       string.rep(string.char(b - 1), len) .. bbuffer[y]:sub(x + len)
   end
-  local F, B = mapping[f], mapping[b]
-  write("\27[38;2;", F&0xFF0000, ";", F&0x00FF00, ";", F&0x0000FF, "m")
-  write("\27[48;2;", B&0xFF0000, ";", B&0x00FF00, ";", B&0x0000FF, "m")
   write("\27[", x, ";", y, "H", text)
+  flush()
 end
 
-local function fullRefresh()
+fullRefresh = function()
   for i=1, h, 1 do
     local text = tbuffer[i]
     local fgt = fbuffer[i]
@@ -89,30 +96,37 @@ local function fullRefresh()
       local str = ""
       if bc ~= pb then
         pb = bc
-        local B = mapping[bc]
+        local B = mapping[bc:byte() + 1]
         str = str .. string.format("\27[48;2;%d;%d;%dm",
-          B&0xFF0000, B&0x00FF00, B&0x0000FF)
+          B&0xFF0000>>16, B&0x00FF00>>8, B&0x0000FF)
       end
       if fc ~= pf then
         pf = fc
-        local F = mapping[fc]
+        local F = mapping[fc:byte() + 1]
         str = str .. string.format("\27[38;2;%d;%d;%dm",
-          F&0xFF0000, F&0x00FF00, F&0x0000FF)
+          F&0xFF0000>>16, F&0x00FF00>>8, F&0x0000FF)
       end
       str = str .. tc
       return str
     end)
-    write("\27[", h, ";1H", fgt)
+    write("\27[", i, ";1H", fgt)
+  end
   flush()
 end
-end
 
-local function get(x, y, len)
+local function get(x, y, len, safe)
   if x < 1 or x > w or y < 1 or y > h then
+    if safe then
+      return
+    else
       error("index out of bounds: " .. y, 3)
     end
+  end
   len = (len or 1) - 1
-  local txt = unsub(tbuffer[y], x, x + len)
+  if x + len > w then
+    len = (x + len) - w
+  end
+  local text = unsub(tbuffer[y], x, x + len)
   if len == 0 then
     return text,
       mapping[fbuffer[y]:sub(x, x):byte() + 1],
@@ -218,6 +232,7 @@ function textgpu.start()
       return true
     else
       set(x, y, text)
+      return true
     end
   end
 
@@ -237,7 +252,7 @@ function textgpu.start()
     if #c == 0 then return true end
     local str = c:rep(W)
     for i=1, h, 1 do
-      set(x, y + i - 1, str)
+      set(x, y + i - 1, str, nil, nil, true)
     end
     return true
   end
@@ -249,15 +264,19 @@ function textgpu.start()
     checkArg(4, H, "number")
     checkArg(5, xd, "number")
     checkArg(6, yd, "number")
+    if xd == 0 and yd == 0 then return true end -- hah
     local start, stop, step
-    if yd > 0 then -- moving up - copy from the top down
+    if yd < 0 then -- moving up - copy from the top down
       start, stop, step = y, y + H, 1
     else -- moving down - copy from the bottom up
       start, stop, step = y + H, y, -1
     end
     for i=start, stop, step do
-      local str, fstr, bstr = get(x, i, W)
-      set(x + xd, i + yd, str, fstr, bstr)
+      local str, fstr, bstr = get(x, i, W, true)
+      if str and fstr and bstr then
+        lprint("GPU_COPY: " .. str .. " FROM " .. i .. " TO " .. (i + yd))
+        set(x + xd, i + yd, str, fstr, bstr, true)
+      end
     end
     fullRefresh()
     return true
@@ -268,7 +287,7 @@ function textgpu.start()
     return screenAddr
   end
 
-  function gpu.bind() end
+  function gpu.bind() --[[STUB]] end
 
   if not termutils.init() then
     return nil, "Cannot initialize terminal based gpu"
@@ -277,6 +296,7 @@ function textgpu.start()
 
   w, h = gpu.getResolution()
   prep(w, h)
+  fullRefresh()
 
   gpu.setForeground(0xFFFFFF)
   gpu.setBackground(0x000000)