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

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Adds a sane way to access each pixel of image data
Adds:
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img:clear([color],[x1],[y1],[x2],[y2])
 (set whole image or a portion to a particular value)
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img:invert([x1],[y1],[x2],[y2])
 (inverts whole image or a portion)
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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)
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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)
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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)
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img:line(x1, y1, x2, y2, color)
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img:ellipse(x1, y1, x2, y2, color, [fillcolor]
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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
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Example lua script to follow on forums
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Change-Id: I7b9c1fd699442fb683760f781021091786c18509
10 files changed