IOS 项目加入SDL库 --- FFMPEG+SDL学习 之 二

在学习FFMPEG的过程中遇到了SDL，但将SDL头文件引入ios项目的时候，发现找不到头文件 -_-！SDL加入项目是需要通用库和头文件的。
我现在的需求是一个能适配iPhone4以上机型和模拟器的通用库。
别急，先回忆一下各个机型和arm体系结构的关系:
Armv6 --- iPhone3G (都老掉牙了，亲~)
Armv7 --- iPhone3GS/4 or iPad
Armv7s --- iPhone5
Simulator --- i386（这个就不属于arm体系了）

对于打库之类的神马，我个人觉得比较麻烦，网上版本很多，解释具体原因的却很少，而且很多资料都过时了，不适应现在的需求。
不过你如果感兴趣，了解一下也是很好的，这里有一篇老外的比较新的blog： 《How to prepare your mac for ios development with ffmpeg libraries 》，
详细告诉了我们在打静态通用库（XXX.a）的步骤，就只有一个Perl脚本，算是比较基础的了。你可以从中看到一些配置项，对你以后理解各种脚本是有好处的。
这里有两个链接：
1.  https://bitbucket.org/DavidLudwig/sdl/src/a325f77bae36?at=default
2.  https://github.com/manifest/sdl-ios-framework

第一个链接我还没尝试过，好像是一个shell脚本，用来生成所需的通用库和头文件的。
我主要是尝试的第二个脚本，貌似是用Python写的，很好理解，只是我对其中的各种环境变量比较生疏。

贴上执行脚本的readme，说的是执行脚本的前提条件，链接里也能找到：

Depends on

tools, you could install them with homebrew   brew install hg

• hg
• git
• svn

rubygems, you could install them with sudo gem install colorize

• colorize

What frameworks are available?

• SDL
• SDL_image
• SDL_mixer
• Tremor

How to use?

rake or rake SDL :build to download sources and build SDL.framework

rake build_all   :to download and install all available frameworks

仔细看了一下，发现这个脚本只是用来生成适配Armv7和Simulator的通用库，可是我还需要匹配Armv7s。
没办法，硬着头皮改了一下吧。
经过一遍又一遍的尝试，终于被我改好了，附上 rakefile文件 ：

#  ------------------------------------------------------------------------------
# Builds a SDL framework  for  the iOS
# Copyright (c)  2011 - 2012  Andrei Nesterov
# See LICENSE  for  licensing information
#  ------------------------------------------------------------------------------
#
# Creates a pseudo - framework which could be used to build iOS applications  for
# both simulator and device
#
#  ------------------------------------------------------------------------------
#
# Depends on tools:
#  hg
#  git
#  svn
#
# Depends on rubygems:
#  colorize
#
#  ------------------------------------------------------------------------------
#
# To configure the script, define:
#   Conf              configuration (:release or :debug)
#   Arch1              architecture  for  the device ' s library (e.g. :armv7)
#   Arch2              architecture  for  the device ' s library (e.g. :armv7s)
#   SDK               version number of the iOS SDK (e.g.  " 4.3 " )
#
#  ------------------------------------------------------------------------------

require  ' rubygems '
require  ' colorize '
require  ' find '

#  ---  Configure  ----------------------------------------------------------------
module Configure
     Conf  =  :release
     Arch1  =  :armv7
     Arch2  =  :armv7s
     SDK  =   ' 6.1 '
end

#  ---  Constants  ----------------------------------------------------------------
module Global
     RootDir  =  Dir.pwd
     TemplatesDir  =   " #{RootDir}/templates "
     SourcesDir  =   " #{RootDir}/src "
     BuildDir  =   " #{RootDir}/build "
end

#  ---  Common  -------------------------------------------------------------------
def message(text)
     tailSize  =   75   -  text.length;
     puts  " \n>>> #{text} #{'-' * (tailSize < 0 ? 0 : tailSize)} " .green
end

def refresystem_dir(path)
     system  % { rm  - rf #{path} }  if  FileTest.exists ?  path
     system  % { mkdir  - p #{path} }
end

module Builder
     def build_library(project, dest, target, conf, sdk, arch)
          dest  =  library_bundle_path(dest, conf, sdk, arch)
          sdk, arch  =  compute_platform(sdk, arch)

          args  =  []
          args  <<   % { - sdk  " #{sdk} " }
          args  <<   % { - configuration  " #{conf} " }
          args  <<   % { - target  " #{target} " }
          args  <<   % { - arch  " #{arch.to_str} " }
          args  <<   % { - project  " #{project} " }
          args  <<   % {TARGETED_DEVICE_FAMILY = " 1,2 " }
          args  <<   % {BUILT_PRODUCTS_DIR = " build " }
          args  <<   % {CONFIGURATION_BUILD_DIR = " #{dest} " }
          args  <<   % {CONFIGURATION_TEMP_DIR = " #{dest}.build " }

          refresystem_dir dest
          Dir.chdir File.dirname(project)  do
               system  % {xcodebuild #{args.join  "   " }}
          end
     end

     def build_framework_library(frameworkLib, deviceLib1, deviceLib2, simulatorLib)
          refresystem_dir(File.dirname(frameworkLib))
          system  % {lipo  - create #{deviceLib1} #{deviceLib2} #{simulatorLib}  - o #{frameworkLib}}
     end

     def build_framework(name, version, identifier, dest, headers, project, target, conf, sdk, arch1, arch2)
          build_library(project, dest, target, conf, sdk, arch1);
          build_library(project, dest, target, conf, sdk, arch2);
          build_library(project, dest, target, conf, sdk, :i386);

          libFileName  =  nil
          Find.find(library_bundle_path(dest, conf, sdk, arch1))  do   | path |
               libFileName  =  File.basename(path)  if  path  =~   / \A. * \.a\z /
          end
          Find.find(library_bundle_path(dest, conf, sdk, arch2))  do   | path |
               libFileName  =  File.basename(path)  if  path  =~   / \A. * \.a\z /
          end
          libFilePath  =   " #{dest}/universal-#{conf}/#{libFileName} "

          build_framework_library(
               libFilePath,
                " #{library_bundle_path(dest, conf, sdk, arch1)}/#{libFileName} " ,
                " #{library_bundle_path(dest, conf, sdk, arch2)}/#{libFileName} " ,
                " #{library_bundle_path(dest, conf, sdk, :i386)}/#{libFileName} "
          )
          create_framework(name, version, identifier, dest, headers, libFilePath)
     end

     def create_framework(name, version, identifier, dest, headers, lib)
          frameworkVersion  =   " A "
          frameworkBundle  =  framework_bundle_path(dest, name)

          # creating framework ' s directories    
          refresystem_dir frameworkBundle
          system  % { mkdir  " #{frameworkBundle}/Versions "  }
          system  % { mkdir  " #{frameworkBundle}/Versions/#{frameworkVersion} "  }
          system  % { mkdir  " #{frameworkBundle}/Versions/#{frameworkVersion}/Resources "  }
          system  % { mkdir  " #{frameworkBundle}/Versions/#{frameworkVersion}/Headers "  }
          system  % { mkdir  " #{frameworkBundle}/Versions/#{frameworkVersion}/Documentation "  }

          # creating framework ' s symlinks
          system  % { ln  - s  " #{frameworkVersion} "   " #{frameworkBundle}/Versions/Current "  }
          system  % { ln  - s  " Versions/Current/Headers "   " #{frameworkBundle}/Headers "  }
          system  % { ln  - s  " Versions/Current/Resources "   " #{frameworkBundle}/Resources "  }
          system  % { ln  - s  " Versions/Current/Documentation "   " #{frameworkBundle}/Documentation "  }
          system  % { ln  - s  " Versions/Current/#{File.basename lib} "   " #{frameworkBundle}/#{name} "  }

          # copying lib
          system  % { cp  " #{lib} "   " #{frameworkBundle}/Versions/#{frameworkVersion} "  }

          # copying includes
          FileList[ " #{headers}/*.h " ].each  do   | source |
               system  % { cp  " #{source} "   " #{frameworkBundle}/Headers "  }
          end

          # creating plist
          File.open( " #{frameworkBundle}/Resources/Info.plist " ,  " w " )  do   | f |
               f.puts  ' <?xml version="1.0" encoding="UTF-8"?>
<! DOCTYPE plist PUBLIC  " -//Apple//DTD PLIST 1.0//EN "   " http://www.apple.com/DTDs/PropertyList-1.0.dtd " >
< plist version = " 1.0 " > '
               f.puts  " <dict>
      < key > CFBundleDevelopmentRegion </ key >
      < string > Englisystem </ string >
      < key > CFBundleExecutable </ key >
      < string > #{name} </ string >
      < key > CFBundleIdentifier </ key >
      < string > #{identifier} </ string >
      < key > CFBundleInfoDictionaryVersion </ key >
      < string > 6.0 </ string >
      < key > CFBundlePackageType </ key >
      < string > FMWK </ string >
      < key > CFBundleSignature </ key >
      < string >????</ string >
      < key > CFBundleVersion </ key >
      < string > #{version} </ string >
</ dict >
</ plist > "
          end
     end

     def library_bundle_path(path, conf, sdk, arch)
          sdk, arch  =  compute_platform(sdk, arch)
           " #{path}/#{sdk}-#{arch}-#{conf} "
     end

     def framework_bundle_path(path, name)
           " #{path}/#{name}.framework "
     end

     def compute_platform(sdk, arch)
           return  [sdk, arch]  if  arch. class   ==  String
          [arch  ==  :i386  ?   " iphonesimulator "   +  sdk :  " iphoneos "   +  sdk, arch.to_s]
     end

      private  :library_bundle_path, :framework_bundle_path, :compute_platform
end

#  ---  Package  ------------------------------------------------------------------
class  Package
     extend Builder

     def self.build(conf, sdk, arch1, arch2)
          download
          unpack
          install(config(conf), sdk, arch1, arch2)
     end

     def self.unpack
     end

     def self.config conf
          conf  ==  :release  ?   " Release "  :  " Debug "
     end
end

#  ---  SDL  ----------------------------------------------------------------------
class  SDL  <  Package
     ProjFile  =   " SDL.xcodeproj "
     SourcesDir  =  (FileTest.exists ?  ProjFile)  ?   " #{Global::RootDir}/../.. "  :  " #{Global::SourcesDir}/SDL "
     BuildDir  =   " #{Global::BuildDir}/sdl "
     Version  =   " 2.0 "

     def self.download
          message  " downloading SDL "
          system  % {hg clone  " http://hg.libsdl.org/SDL "   " #{SourcesDir} " }
     end
    
     def self.install(conf, sdk, arch1, arch2)
          message  " building SDL "
          self.build_framework(
                " SDL " ,
               Version,
                " org.libsdl " ,
               BuildDir,
                " #{SourcesDir}/include " ,
                " #{SourcesDir}/Xcode-iOS/SDL/#{ProjFile} " ,
                " libSDL " ,
               conf,
               sdk,
               arch1,
               arch2
          )
     end
end

#  ---  SDL_image  ----------------------------------------------------------------
class  SDL_image  <  Package
     SourcesDir  =   " #{Global::SourcesDir}/sdl_image "
     BuildDir  =   " #{Global::BuildDir}/sdl_image "
     Version  =   " 1.2.12 "
 
     def self.download
          message  " downloading SDL_image "
          system  % {hg clone  " http://hg.libsdl.org/SDL_image "   " #{SourcesDir} " }
     end
    
     def self.install(conf, sdk, arch1, arch2)
          message  " building SDL_image "
          self.build_framework(
                " SDL_image " ,
               Version,
                " org.libsdl " ,
               BuildDir,
                " #{SourcesDir} " ,
                " #{SourcesDir}/Xcode-iOS/SDL_image.xcodeproj " ,
                " libSDL_image " ,
               conf,
               sdk,
               arch1,
               arch2
          )
     end
end

#  ---  SDL_mixer  ----------------------------------------------------------------
class  SDL_mixer  <  Package
     SourcesDir  =   " #{Global::SourcesDir}/sdl_mixer "
     BuildDir  =   " #{Global::BuildDir}/sdl_mixer "
     Version  =   " 1.2.12 "

     def self.download
          message  " downloading SDL_mixer "
          system  % {hg clone  " http://hg.libsdl.org/SDL_mixer "   " #{SourcesDir} " }
     end
    
     def self.install(conf, sdk, arch1, arch2)
          message  " creating links on vorbis headers for successful SDL_mixer building "
          refresystem_dir(headersDir  =   " #{Global::SourcesDir}/libtremor " )
          system  % { ln  - s  " #{Tremor::BuildDir}/vorbis.framework/Headers "   " #{headersDir}/ogg "  }
          system  % { ln  - s  " #{Tremor::BuildDir}/vorbis.framework/Headers "   " #{headersDir}/tremor "  }

          message  " building SDL_mixer "
          self.build_framework(
                " SDL_mixer " ,
               Version,
                " org.libsdl " ,
               BuildDir,
                " #{SourcesDir} " ,
                " #{SourcesDir}/Xcode-iOS/SDL_mixer.xcodeproj " ,
                " Static Library " ,
               conf,
               sdk,
               arch1,
               arch2
          )

          system  % { rm  - rf #{headersDir} }
     end
end

#  ---  Tremor  -------------------------------------------------------------------
class  Tremor  <  Package
     SourcesDir  =   " #{Global::SourcesDir}/cocos2d "
     BuildDir  =   " #{Global::BuildDir}/tremor "
     Version  =   " 1.3.2 "

     def self.download
          message  " downloading Cocos2d "
          system  % {git clone  " https://github.com/cocos2d/cocos2d-iphone.git "   " #{SourcesDir} " }
     end
    
     def self.install(conf, sdk, arch1, arch2)
          message  " switching to v1.x brunch "
          Dir.chdir(SourcesDir)  do
               system  ' git checkout master '
          end

          message  " building Tremor "
          self.build_framework(
                " vorbis " ,
               Version,
                " org.xiph " ,
               BuildDir,
                " #{SourcesDir}/external/Tremor " ,
                " #{SourcesDir}/cocos2d-ios.xcodeproj " ,
                " vorbis " ,
               conf,
               sdk,
               arch1,
               arch2
          )
     end
end

#  ---  Tasks  --------------------------------------------------------------------
require  ' rake/clean '

Libs  =  [:SDL, :SDL_image, :Tremor, :SDL_mixer]

desc  " Download sources and build SDL.framework "
task : default   =>  [ " SDL:build " ]  do
end

desc  " Download sources and build all targets [#{Libs.join  " ,  " }] "
task :build_all  do
     Libs.each  do   | classname |
          Object.const_get(classname).build Configure::Conf, Configure::SDK, Configure::Arch1, Configure::Arch2
     end
end

Libs.each  do   | classname |
      namespace  classname  do
          obj  =  Object.const_get(classname)

          desc  " Download sources and build #{classname}.framework "
          task :build  do
               obj.build Configure::Conf, Configure::SDK, Configure::Arch1, Configure::Arch2
          end

          desc  " Only download #{classname} sources "
          task :download  do
               obj.download
               obj.unpack
          end

          desc  " Only build #{classname}.framework "
          task :install  do
               obj.install Configure::Conf, Configure::SDK, Configure::Arch1, Configure::Arch2
          end

          desc  " Remove all files associated with #{classname} "
          task :clobber  do
               CLOBBER  =  Rake::FileList. new
               CLOBBER.include obj::SourcesDir, obj::BuildDir
               Rake::Task[:clobber].execute
          end
     end
end

CLOBBER.include Global::SourcesDir, Global::BuildDir

一切都是自动化安装，
稍微注意一下的是自己的sdk版本，我的是6.1。
还有最后一个小问题，SDL需要4个framework支持：
CoreGraphics
QuartzCore
OpenGLES
AudioToolbox
所以ios项目也要对应的引入这4个framework。