Rocklua -- Extend / Fix rliImage

Some devices(1-bit / 2-bit displays) have packed bit formats that
 need to be unpacked in order to work on them at a pixel level.

This caused a few issues on 1 & 2-bit devices:
 Greatly Oversized data arrays for bitmaps
 Improper handling of native image data
 Framebuffer data was near unusable without jumping through hoops

Conversion between native addressing and per pixel addressing
 incurs extra overhead but it is much faster to do it
 on the 'C' side rather than in lua.

Not to mention the advantage of a unified interface for the end programer

-------------------------------------------------------------------
Adds a sane way to access each pixel of image data
Adds:
--------------------------------------------------------------------
img:clear([color],[x1],[y1],[x2],[y2])
 (set whole image or a portion to a particular value)
--------------------------------------------------------------------
img:invert([x1],[y1],[x2],[y2])
 (inverts whole image or a portion)
--------------------------------------------------------------------
img:marshal([x1],[y1],[x2],[y2],[funct])
 (calls funct for each point defined by rect of x1,y1 x2,y2
  returns value and allows setting value of each point return
  nil to terminate early)
--------------------------------------------------------------------
img:points([x1],[y1],[x2],[y2],[dx],[dy])
 (returns iterator function that steps delta-x and delta-y pixels each call
  returns value of pixel each call but doesn't allow setting to a new value
  compare to lua pairs method)
--------------------------------------------------------------------
img:copy(src,[x1],[y1],[x2],[y2],[w],[h],[clip][operation][clr/funct])
 (copies all or part of an image -- straight copy or special ops
  optionally calls funct for each point defined by rect of
  x1, y1, w, h and  x2, y2, w, h for dest and src images
  returns value of dst and src and allows setting value of
  each point return nil to terminate early)
--------------------------------------------------------------------
img:line(x1, y1, x2, y2, color)
--------------------------------------------------------------------
img:ellipse(x1, y1, x2, y2, color, [fillcolor]
--------------------------------------------------------------------
Fixed handling of 2-bit vertical integrated screens

Added direct element access for saving / restoring native image etc.

Added more data to tostring() handler and a way to access individual items

Added equals method to see if two variables reference the same image address
(doesn't check if two separate images contain the same 'picture')

Optimized get and set routines

Fixed out of bound x coord access shifting to next line

Added lua include files to expose new functionality

Finished image saving routine

Static allocation of set_viewport struct faster + saves ram over dynamic

Cleaned up code

Fixed pixel get/set for 1/2 bit devices
-------------------------------------------------------------------------
Example lua script to follow on forums
-------------------------------------------------------------------------

Change-Id: I7b9c1fd699442fb683760f781021091786c18509

1 files changed, 153 insertions, 0 deletions

diff --git a/apps/plugins/lua/include_lua/lcd.lua b/apps/plugins/lua/include_lua/lcd.lua
new file mode 100644
index 0000000000..62fa988ec1
--- /dev/null
+++ b/apps/plugins/lua/include_lua/lcd.lua
@@ -0,0 +1,153 @@
+--[[ Lua LCD Wrapper functions
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2017 William Wilgus
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+]]
+
+--[[ Exposed Functions
+
+    _lcd.clear
+    _lcd.duplicate
+    _lcd.image
+    _lcd.set_viewport
+    _lcd.splashf
+    _lcd.text_extent
+    _lcd.update
+    _lcd.update_rect
+
+-- Exposed Constants
+    _lcd.CX
+    _lcd.CY
+    _lcd.DEPTH
+    _lcd.W
+    _lcd.H
+
+    _lcd
+    _LCD
+
+]]
+if not rb.lcd_framebuffer then rb.splash(rb.HZ, "No Support!") return nil end
+
+_LCD = rb.lcd_framebuffer()
+
+local _lcd = {} do
+
+    --internal constants
+    local _NIL = nil -- _NIL placeholder
+    local LCD_W, LCD_H = rb.LCD_WIDTH, rb.LCD_HEIGHT
+
+   -- clamps value to >= min and <= max
+    local function clamp(val, min, max)
+        -- Warning doesn't check if min < max
+        if val < min then
+            return min
+        elseif val < max then
+            return val
+        end
+        return max
+    end
+
+    -- return a copy of lcd screen
+    local function duplicate(t, screen_img)
+        screen_img = screen_img or rb.new_image()
+        screen_img:copy(rb.lcd_framebuffer())
+        return screen_img
+    end
+
+    -- updates screen in specified rectangle
+    local function update_rect(t, x, y, w, h)
+        rb.lcd_update_rect(x - 1, y - 1,
+             clamp(x + w, 1, LCD_W) - 1,
+             clamp(y + h, 1, LCD_H) - 1)
+    end
+
+    -- clears lcd, optional.. ([color, x1, y1, x2, y2, clip])
+    local function clear(t, clr, ...)
+        if clr == _NIL and ... == _NIL then
+            rb.lcd_clear_display()
+        else
+            rb.lcd_scroll_stop() --rb really doesn't like bg change while scroll
+            _LCD:clear(clr, ...)
+        end
+    end
+
+    -- loads an image to the screen
+    local function image(t, src, x, y)
+        if not src then --make sure an image was passed, otherwise bail
+            rb.splash(rb.HZ, "No Image!")
+            return _NIL
+        end
+        _LCD:copy(src,x,y,1,1)
+    end
+
+    -- Formattable version of splash
+    local function splashf(t, timeout, ...)
+        rb.splash(timeout, string.format(...))
+    end
+
+    -- Gets size of text
+    local function text_extent(t, msg, font)
+        font = font or rb.FONT_UI
+
+        return rb.font_getstringsize(msg, font)
+    end
+
+    -- Sets viewport size
+    local function set_viewport(t, vp)
+        if not vp then rb.set_viewport() return end
+        if rb.LCD_DEPTH  == 2 then -- invert 2-bit screens
+            --vp.drawmode = bit.bxor(vp.drawmode, 4)
+            vp.fg_pattern = 3 - vp.fg_pattern
+            vp.bg_pattern = 3 - vp.bg_pattern
+        end
+        rb.set_viewport(vp)
+    end
+
+    -- allows the use of _lcd() as a identifier for the screen
+    local function index(k, v)
+        return function(x, ...)
+            _LCD[v](_LCD, ...)
+        end
+    end
+
+    -- allows the use of _lcd() as a identifier for the screen
+    local function call()
+        return rb.lcd_framebuffer()
+    end
+
+    --expose functions to the outside through _lcd table
+    _lcd.text_extent  = text_extent
+    _lcd.set_viewport = set_viewport
+    _lcd.duplicate    = duplicate
+    _lcd.update       = rb.lcd_update
+    _lcd.update_rect  = update_rect
+    _lcd.clear        = clear
+    _lcd.splashf      = splashf
+    _lcd.image        = image
+    _lcd.DEPTH        = rb.LCD_DEPTH
+    _lcd.W            = rb.LCD_WIDTH
+    _lcd.H            = rb.LCD_HEIGHT
+    _lcd.CX           = (rb.LCD_WIDTH / 2)
+    _lcd.CY           = (rb.LCD_HEIGHT / 2)
+    _lcd = setmetatable(_lcd,{__index = index, __call = call})
+
+end -- _lcd functions
+
+return _lcd