SDL's build system was traditionally based on autotools. Over time, this

approach has suffered from several issues across the different supported

platforms.

To solve these problems, a new build system based on CMake is under development.

It works in parallel to the legacy system, so users can experiment with it

without complication.

While still experimental, the build system should be usable on the following

platforms:

* FreeBSD

* Linux

* VS.NET 2010

* MinGW and Msys

================================================================================

Usage

================================================================================

Assuming the source for SDL is located at ~/sdl

cd ~

mkdir build

cd build

cmake ../sdl

This will build the static and dynamic versions of SDL in the ~/build directory.

================================================================================

Usage, iOS/tvOS

================================================================================

CMake 3.14+ natively includes support for iOS and tvOS. SDL binaries may be built

using Xcode or Make, possibly among other build-systems.

When using a recent version of CMake (3.14+), it should be possible to:

- build SDL for iOS, both static and dynamic

- build SDL test apps (as iOS/tvOS .app bundles)

- generate a working SDL_config.h for iOS (using SDL_config.h.cmake as a basis)

To use, set the following CMake variables when running CMake's configuration stage:

- `CMAKE_SYSTEM_NAME=<OS>` (either `iOS` or `tvOS`)

- `CMAKE_OSX_SYSROOT=<SDK>` (examples: `iphoneos`, `iphonesimulator`, `iphoneos12.4`, `/full/path/to/iPhoneOS.sdk`,

`appletvos`, `appletvsimulator`, `appletvos12.4`, `/full/path/to/AppleTVOS.sdk`, etc.)

- `CMAKE_OSX_ARCHITECTURES=<semicolon-separated list of CPU architectures>` (example: "arm64;armv7s;x86_64")

### Examples (for iOS/tvOS):

- for iOS-Simulator, using the latest, installed SDK:

`cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64`

- for iOS-Device, using the latest, installed SDK, 64-bit only

`cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES=arm64`

- for iOS-Device, using the latest, installed SDK, mixed 32/64 bit

`cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES="arm64;armv7s"`

- for iOS-Device, using a specific SDK revision (iOS 12.4, in this example):

`cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos12.4 -DCMAKE_OSX_ARCHITECTURES=arm64`

- for iOS-Simulator, using the latest, installed SDK, and building SDL test apps (as .app bundles):

`cmake ~/sdl -DSDL_TEST=1 -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64`

- for tvOS-Simulator, using the latest, installed SDK:

- for tvOS-Device, using the latest, installed SDK: