1 Skia Lua Bindings 2 ================= 3 4 **Warning: The following has only been tested on Linux, but it will likely 5 work for any Unix.** 6 7 Prerequisites 8 ------------- 9 10 This assumes one already has Skia building normally. If not, refer to the 11 quick start guides. In addition to that, you will need Lua 5.2 installed on 12 your system in order to use the bindings. 13 14 Building lua requires the readline development library. If missing this can be installed (on Ubuntu) by executing: 15 16 * `apt-cache search libreadline` to see the available libreadline libraries 17 * `sudo apt-get install libreadline6 libreadline6-dev` to actually install the libraries 18 19 Build 20 ----- 21 22 The build process starts the same way as described in the quick starts, but 23 before using gyp or make, do this instead: 24 25 $ export GYP_DEFINES="skia_shared_lib=1" 26 $ make tools 27 28 This tells Skia to build as a shared library, which enables a build of another shared library called 'skia.so' that exposes Skia bindings to Lua. 29 30 Try It Out 31 ---------- 32 33 Once the build is complete, use the same terminal: 34 35 $ cd out/Debug/ 36 $ lua 37 38 Lua 5.2.0 Copyright (C) 1994-2011 Lua.org, PUC-Rio 39 > require 'skia' 40 > paint = Sk.newPaint() 41 > paint:setColor{a=1, r=1, g=0, b=0} 42 > doc = Sk.newDocumentPDF('test.pdf') 43 > canvas = doc:beginPage(72*8.5, 72*11) 44 > canvas:drawText('Hello Lua', 300, 300, paint) 45 > doc:close() 46 47 The key part to loading the bindings is `require 'skia'` which tells lua to look 48 for 'skia.so' in the current directory (among many others) and provides the 49 bindings. 'skia.so' in turn will load 'libskia.so' from the current directory or 50 in our case the lib.target directory. 'libskia.so' is what contains the native 51 skia code. The script shown above uses skia to draw Hello Lua in red text onto 52 a pdf that will be outputted into the current folder as 'test.pdf'. Go ahead and 53 open 'test.pdf' to confirm that everything is working. 54 55