Commit 4b6a4125 authored by Rustom Jehangir's avatar Rustom Jehangir
Browse files

SDL2: Add Windows SDL2 development files.

parent 7c71f38c
Bugs are now managed in the SDL bug tracker, here:
http://bugzilla.libsdl.org/
You may report bugs there, and search to see if a given issue has already
been reported, discussed, and maybe even fixed.
You may also find help on the SDL mailing list. Subscription information:
http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org
Bug reports are welcome here, but we really appreciate if you use Bugzilla, as
bugs discussed on the mailing list may be forgotten or missed.
Simple DirectMedia Layer
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
Please distribute this file with the SDL runtime environment:
The Simple DirectMedia Layer (SDL for short) is a cross-platform library
designed to make it easy to write multi-media software, such as games and
emulators.
The Simple DirectMedia Layer library source code is available from:
http://www.libsdl.org/
This library is distributed under the terms of the zlib license:
http://www.zlib.net/zlib_license.html
Simple DirectMedia Layer
(SDL)
Version 2.0
---
http://www.libsdl.org/
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
More extensive documentation is available in the docs directory, starting
with README.md
Enjoy!
Sam Lantinga (slouken@libsdl.org)
This is a list of major changes in SDL's version history.
---------------------------------------------------------------------------
2.0.4:
---------------------------------------------------------------------------
General:
* Added support for web applications using Emscripten, see docs/README-emscripten.md for more information
* Added support for web applications using Native Client (NaCl), see docs/README-nacl.md for more information
* Added an API to queue audio instead of using the audio callback:
SDL_QueueAudio(), SDL_GetQueuedAudioSize(), SDL_ClearQueuedAudio()
* Added events for audio device hot plug support:
SDL_AUDIODEVICEADDED, SDL_AUDIODEVICEREMOVED
* Added SDL_PointInRect()
* Added SDL_HasAVX2() to detect CPUs with AVX2 support
* Added SDL_SetWindowHitTest() to let apps treat parts of their SDL window like traditional window decorations (drag areas, resize areas)
* Added SDL_GetGrabbedWindow() to get the window that currently has input grab, if any
* Added SDL_RenderIsClipEnabled() to tell whether clipping is currently enabled in a renderer
* Added SDL_CaptureMouse() to capture the mouse to get events while the mouse is not in your window
* Added SDL_WarpMouseGlobal() to warp the mouse cursor in global screen space
* Added SDL_GetGlobalMouseState() to get the current mouse state outside of an SDL window
* Added a direction field to mouse wheel events to tell whether they are flipped (natural) or not
* Added GL_CONTEXT_RELEASE_BEHAVIOR GL attribute (maps to [WGL|GLX]_ARB_context_flush_control extension)
* Added EGL_KHR_create_context support to allow OpenGL ES version selection on some platforms
* Added NV12 and NV21 YUV texture support for OpenGL and OpenGL ES 2.0 renderers
* Added a Vivante video driver that is used on various SoC platforms
* Added an event SDL_RENDER_DEVICE_RESET that is sent from the D3D renderers when the D3D device is lost, and from Android's event loop when the GLES context had to be recreated
* Added a hint SDL_HINT_NO_SIGNAL_HANDLERS to disable SDL's built in signal handling
* Added a hint SDL_HINT_THREAD_STACK_SIZE to set the stack size of SDL's threads
* Added SDL_sqrtf(), SDL_tan(), and SDL_tanf() to the stdlib routines
* Improved support for WAV and BMP files with unusual chunks in them
* Renamed SDL_assert_data to SDL_AssertData and SDL_assert_state to SDL_AssertState
* Added a hint SDL_HINT_WINDOW_FRAME_USABLE_WHILE_CURSOR_HIDDEN to prevent window interaction while cursor is hidden
* Added SDL_GetDisplayDPI() to get the DPI information for a display
* Added SDL_JoystickCurrentPowerLevel() to get the battery level of a joystick
* Added SDL_JoystickFromInstanceID(), as a helper function, to get the SDL_Joystick* that an event is referring to.
* Added SDL_GameControllerFromInstanceID(), as a helper function, to get the SDL_GameController* that an event is referring to.
Windows:
* Added support for Windows Phone 8.1 and Windows 10/UWP (Universal Windows Platform)
* Timer resolution is now 1 ms by default, adjustable with the SDL_HINT_TIMER_RESOLUTION hint
* SDLmain no longer depends on the C runtime, so you can use the same .lib in both Debug and Release builds
* Added SDL_SetWindowsMessageHook() to set a function to be called for every windows message before TranslateMessage()
* Added a hint SDL_HINT_WINDOWS_ENABLE_MESSAGELOOP to control whether SDL_PumpEvents() processes the Windows message loop
* You can distinguish between real mouse and touch events by looking for SDL_TOUCH_MOUSEID in the mouse event "which" field
* SDL_SysWMinfo now contains the window HDC
* Added support for Unicode command line options
* Prevent beeping when Alt-key combos are pressed
* SDL_SetTextInputRect() re-positions the OS-rendered IME
* Added a hint SDL_HINT_WINDOWS_NO_CLOSE_ON_ALT_F4 to prevent generating SDL_WINDOWEVENT_CLOSE events when Alt-F4 is pressed
* Added a hint SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING to use the old axis and button mapping for XInput devices (deprecated)
Mac OS X:
* Implemented drag-and-drop support
* Improved joystick hot-plug detection
* The SDL_WINDOWEVENT_EXPOSED window event is triggered in the appropriate situations
* Fixed relative mouse mode when the application loses/regains focus
* Fixed bugs related to transitioning to and from Spaces-aware fullscreen-desktop mode
* Fixed the refresh rate of display modes
* SDL_SysWMInfo is now ARC-compatible
* Added a hint SDL_HINT_MAC_BACKGROUND_APP to prevent forcing the application to become a foreground process
Linux:
* Enabled building with Mir and Wayland support by default.
* Added IBus IME support
* Added a hint SDL_HINT_IME_INTERNAL_EDITING to control whether IBus should handle text editing internally instead of sending SDL_TEXTEDITING events
* Added a hint SDL_HINT_VIDEO_X11_NET_WM_PING to allow disabling _NET_WM_PING protocol handling in SDL_CreateWindow()
* Added support for multiple audio devices when using Pulseaudio
* Fixed duplicate mouse events when using relative mouse motion
iOS:
* Added support for iOS 8
* The SDL_WINDOW_ALLOW_HIGHDPI window flag now enables high-dpi support, and SDL_GL_GetDrawableSize() or SDL_GetRendererOutputSize() gets the window resolution in pixels
* SDL_GetWindowSize() and display mode sizes are in the "DPI-independent points" / "screen coordinates" coordinate space rather than pixels (matches OS X behavior)
* Added native resolution support for the iPhone 6 Plus
* Added support for MFi game controllers
* Added support for the hint SDL_HINT_ACCELEROMETER_AS_JOYSTICK
* Added sRGB OpenGL ES context support on iOS 7+
* Added support for SDL_DisableScreenSaver(), SDL_EnableScreenSaver() and the hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER
* SDL_SysWMinfo now contains the OpenGL ES framebuffer and color renderbuffer objects used by the window's active GLES view
* Fixed various rotation and orientation issues
* Fixed memory leaks
Android:
* Added a hint SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH to prevent mouse events from being registered as touch events
* Added hints SDL_HINT_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION and SDL_HINT_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION
* Added support for SDL_DisableScreenSaver(), SDL_EnableScreenSaver() and the hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER
* Added support for SDL_ShowMessageBox() and SDL_ShowSimpleMessageBox()
Raspberry Pi:
* Added support for the Raspberry Pi 2
---------------------------------------------------------------------------
2.0.3:
---------------------------------------------------------------------------
Mac OS X:
* Fixed creating an OpenGL context by default on Mac OS X 10.6
---------------------------------------------------------------------------
2.0.2:
---------------------------------------------------------------------------
General:
* Added SDL_GL_ResetAttributes() to reset OpenGL attributes to default values
* Added an API to load a database of game controller mappings from a file:
SDL_GameControllerAddMappingsFromFile(), SDL_GameControllerAddMappingsFromRW()
* Added game controller mappings for the PS4 and OUYA controllers
* Added SDL_GetDefaultAssertionHandler() and SDL_GetAssertionHandler()
* Added SDL_DetachThread()
* Added SDL_HasAVX() to determine if the CPU has AVX features
* Added SDL_vsscanf(), SDL_acos(), and SDL_asin() to the stdlib routines
* EGL can now create/manage OpenGL and OpenGL ES 1.x/2.x contexts, and share
them using SDL_GL_SHARE_WITH_CURRENT_CONTEXT
* Added a field "clicks" to the mouse button event which records whether the event is a single click, double click, etc.
* The screensaver is now disabled by default, and there is a hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER that can change that behavior.
* Added a hint SDL_HINT_MOUSE_RELATIVE_MODE_WARP to specify whether mouse relative mode should be emulated using mouse warping.
* testgl2 does not need to link with libGL anymore
* Added testgles2 test program to demonstrate working with OpenGL ES 2.0
* Added controllermap test program to visually map a game controller
Windows:
* Support for OpenGL ES 2.x contexts using either WGL or EGL (natively via
the driver or emulated through ANGLE)
* Added a hint SDL_HINT_VIDEO_WIN_D3DCOMPILER to specify which D3D shader compiler to use for OpenGL ES 2 support through ANGLE
* Added a hint SDL_HINT_VIDEO_WINDOW_SHARE_PIXEL_FORMAT that is useful when creating multiple windows that should share the same OpenGL context.
* Added an event SDL_RENDER_TARGETS_RESET that is sent when D3D9 render targets are reset after the device has been restored.
Mac OS X:
* Added a hint SDL_HINT_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK to control whether Ctrl+click should be treated as a right click on Mac OS X. This is off by default.
Linux:
* Fixed fullscreen and focused behavior when receiving NotifyGrab events
* Added experimental Wayland and Mir support, disabled by default
Android:
* Joystick support (minimum SDK version required to build SDL is now 12,
the required runtime version remains at 10, but on such devices joystick
support won't be available).
* Hotplugging support for joysticks
* Added a hint SDL_HINT_ACCELEROMETER_AS_JOYSTICK to control whether the accelerometer should be listed as a 3 axis joystick, which it will by default.
---------------------------------------------------------------------------
2.0.1:
---------------------------------------------------------------------------
General:
* Added an API to get common filesystem paths in SDL_filesystem.h:
SDL_GetBasePath(), SDL_GetPrefPath()
* Added an API to do optimized YV12 and IYUV texture updates:
SDL_UpdateYUVTexture()
* Added an API to get the amount of RAM on the system:
SDL_GetSystemRAM()
* Added a macro to perform timestamp comparisons with SDL_GetTicks():
SDL_TICKS_PASSED()
* Dramatically improved OpenGL ES 2.0 rendering performance
* Added OpenGL attribute SDL_GL_FRAMEBUFFER_SRGB_CAPABLE
Windows:
* Created a static library configuration for the Visual Studio 2010 project
* Added a hint to create the Direct3D device with support for multi-threading:
SDL_HINT_RENDER_DIRECT3D_THREADSAFE
* Added a function to get the D3D9 adapter index for a display:
SDL_Direct3D9GetAdapterIndex()
* Added a function to get the D3D9 device for a D3D9 renderer:
SDL_RenderGetD3D9Device()
* Fixed building SDL with the mingw32 toolchain (mingw-w64 is preferred)
* Fixed crash when using two XInput controllers at the same time
* Fixed detecting a mixture of XInput and DirectInput controllers
* Fixed clearing a D3D render target larger than the window
* Improved support for format specifiers in SDL_snprintf()
Mac OS X:
* Added support for retina displays:
Create your window with the SDL_WINDOW_ALLOW_HIGHDPI flag, and then use SDL_GL_GetDrawableSize() to find the actual drawable size. You are responsible for scaling mouse and drawing coordinates appropriately.
* Fixed mouse warping in fullscreen mode
* Right mouse click is emulated by holding the Ctrl key while left clicking
Linux:
* Fixed float audio support with the PulseAudio driver
* Fixed missing line endpoints in the OpenGL renderer on some drivers
* X11 symbols are no longer defined to avoid collisions when linking statically
iOS:
* Fixed status bar visibility on iOS 7
* Flipped the accelerometer Y axis to match expected values
Android:
IMPORTANT: You MUST get the updated SDLActivity.java to match C code
* Moved EGL initialization to native code
* Fixed the accelerometer axis rotation relative to the device rotation
* Fixed race conditions when handling the EGL context on pause/resume
* Touch devices are available for enumeration immediately after init
Raspberry Pi:
* Added support for the Raspberry Pi, see README-raspberrypi.txt for details
This diff is collapsed.
CMake
================================================================================
(www.cmake.org)
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
* OS X with support for XCode
================================================================================
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.
DirectFB
========
Supports:
- Hardware YUV overlays
- OpenGL - software only
- 2D/3D accelerations (depends on directfb driver)
- multiple displays
- windows
What you need:
* DirectFB 1.0.1, 1.2.x, 1.3.0
* Kernel-Framebuffer support: required: vesafb, radeonfb ....
* Mesa 7.0.x - optional for OpenGL
/etc/directfbrc
This file should contain the following lines to make
your joystick work and avoid crashes:
------------------------
disable-module=joystick
disable-module=cle266
disable-module=cyber5k
no-linux-input-grab
------------------------
To disable to use x11 backend when DISPLAY variable is found use
export SDL_DIRECTFB_X11_CHECK=0
To disable the use of linux input devices, i.e. multimice/multikeyboard support,
use
export SDL_DIRECTFB_LINUX_INPUT=0
To use hardware accelerated YUV-overlays for YUV-textures, use:
export SDL_DIRECTFB_YUV_DIRECT=1
This is disabled by default. It will only support one
YUV texture, namely the first. Every other YUV texture will be
rendered in software.
In addition, you may use (directfb-1.2.x)
export SDL_DIRECTFB_YUV_UNDERLAY=1
to make the YUV texture an underlay. This will make the cursor to
be shown.
Simple Window Manager
=====================
The driver has support for a very, very basic window manager you may
want to use when running with "wm=default". Use
export SDL_DIRECTFB_WM=1
to enable basic window borders. In order to have the window title rendered,
you need to have the following font installed:
/usr/share/fonts/truetype/freefont/FreeSans.ttf
OpenGL Support
==============
The following instructions will give you *software* OpenGL. However this
works at least on all directfb supported platforms.
As of this writing 20100802 you need to pull Mesa from git and do the following:
------------------------
git clone git://anongit.freedesktop.org/git/mesa/mesa
cd mesa
git checkout 2c9fdaf7292423c157fc79b5ce43f0f199dd753a
------------------------
Edit configs/linux-directfb so that the Directories-section looks like
------------------------
# Directories
SRC_DIRS = mesa glu
GLU_DIRS = sgi
DRIVER_DIRS = directfb
PROGRAM_DIRS =
------------------------
make linux-directfb
make
echo Installing - please enter sudo pw.
sudo make install INSTALL_DIR=/usr/local/dfb_GL
cd src/mesa/drivers/directfb
make
sudo make install INSTALL_DIR=/usr/local/dfb_GL
------------------------
To run the SDL - testprograms:
export SDL_VIDEODRIVER=directfb
export LD_LIBRARY_PATH=/usr/local/dfb_GL/lib
export LD_PRELOAD=/usr/local/dfb_GL/libGL.so.7
./testgl
Dynamic API
================================================================================
Originally posted by Ryan at:
https://plus.google.com/103391075724026391227/posts/TB8UfnDYu4U
Background:
- The Steam Runtime has (at least in theory) a really kick-ass build of SDL2,
but developers are shipping their own SDL2 with individual Steam games.
These games might stop getting updates, but a newer SDL2 might be needed later.
Certainly we'll always be fixing bugs in SDL, even if a new video target isn't
ever needed, and these fixes won't make it to a game shipping its own SDL.
- Even if we replace the SDL2 in those games with a compatible one, that is to
say, edit a developer's Steam depot (yuck!), there are developers that are
statically linking SDL2 that we can't do this for. We can't even force the
dynamic loader to ignore their SDL2 in this case, of course.
- If you don't ship an SDL2 with the game in some form, people that disabled the
Steam Runtime, or just tried to run the game from the command line instead of
Steam might find themselves unable to run the game, due to a missing dependency.
- If you want to ship on non-Steam platforms like GOG or Humble Bundle, or target
generic Linux boxes that may or may not have SDL2 installed, you have to ship
the library or risk a total failure to launch. So now, you might have to have
a non-Steam build plus a Steam build (that is, one with and one without SDL2
included), which is inconvenient if you could have had one universal build
that works everywhere.
- We like the zlib license, but the biggest complaint from the open source
community about the license change is the static linking. The LGPL forced this
as a legal, not technical issue, but zlib doesn't care. Even those that aren't
concerned about the GNU freedoms found themselves solving the same problems:
swapping in a newer SDL to an older game often times can save the day.
Static linking stops this dead.
So here's what we did:
SDL now has, internally, a table of function pointers. So, this is what SDL_Init
now looks like:
UInt32 SDL_Init(Uint32 flags)
{
return jump_table.SDL_Init(flags);
}
Except that is all done with a bunch of macro magic so we don't have to maintain
every one of these.
What is jump_table.SDL_init()? Eventually, that's a function pointer of the real
SDL_Init() that you've been calling all this time. But at startup, it looks more
like this:
Uint32 SDL_Init_DEFAULT(Uint32 flags)
{
SDL_InitDynamicAPI();
return jump_table.SDL_Init(flags);
}
SDL_InitDynamicAPI() fills in jump_table with all the actual SDL function
pointers, which means that this _DEFAULT function never gets called again.
First call to any SDL function sets the whole thing up.
So you might be asking, what was the value in that? Isn't this what the operating
system's dynamic loader was supposed to do for us? Yes, but now we've got this
level of indirection, we can do things like this:
export SDL_DYNAMIC_API=/my/actual/libSDL-2.0.so.0
./MyGameThatIsStaticallyLinkedToSDL2
And now, this game that is staticallly linked to SDL, can still be overridden
with a newer, or better, SDL. The statically linked one will only be used as
far as calling into the jump table in this case. But in cases where no override
is desired, the statically linked version will provide its own jump table,
and everyone is happy.
So now:
- Developers can statically link SDL, and users can still replace it.
(We'd still rather you ship a shared library, though!)
- Developers can ship an SDL with their game, Valve can override it for, say,
new features on SteamOS, or distros can override it for their own needs,
but it'll also just work in the default case.
- Developers can ship the same package to everyone (Humble Bundle, GOG, etc),
and it'll do the right thing.
- End users (and Valve) can update a game's SDL in almost any case,
to keep abandoned games running on newer platforms.
- Everyone develops with SDL exactly as they have been doing all along.
Same headers, same ABI. Just get the latest version to enable this magic.
A little more about SDL_InitDynamicAPI():
Internally, InitAPI does some locking to make sure everything waits until a
single thread initializes everything (although even SDL_CreateThread() goes
through here before spinning a thread, too), and then decides if it should use
an external SDL library. If not, it sets up the jump table using the current
SDL's function pointers (which might be statically linked into a program, or in
a shared library of its own). If so, it loads that library and looks for and
calls a single function:
SInt32 SDL_DYNAPI_entry(Uint32 version, void *table, Uint32 tablesize);
That function takes a version number (more on that in a moment), the address of
the jump table, and the size, in bytes, of the table.
Now, we've got policy here: this table's layout never changes; new stuff gets
added to the end. Therefore SDL_DYNAPI_entry() knows that it can provide all
the needed functions if tablesize <= sizeof its own jump table. If tablesize is
bigger (say, SDL 2.0.4 is trying to load SDL 2.0.3), then we know to abort, but
if it's smaller, we know we can provide the entire API that the caller needs.
The version variable is a failsafe switch.
Right now it's always 1. This number changes when there are major API changes
(so we know if the tablesize might be smaller, or entries in it have changed).
Right now SDL_DYNAPI_entry gives up if the version doesn't match, but it's not
inconceivable to have a small dispatch library that only supplies this one
function and loads different, otherwise-incompatible SDL libraries and has the
right one initialize the jump table based on the version. For something that
must generically catch lots of different versions of SDL over time, like the
Steam Client, this isn't a bad option.
Finally, I'm sure some people are reading this and thinking,
"I don't want that overhead in my project!"
To which I would point out that the extra function call through the jump table
probably wouldn't even show up in a profile, but lucky you: this can all be
disabled. You can build SDL without this if you absolutely must, but we would
encourage you not to do that. However, on heavily locked down platforms like
iOS, or maybe when debugging, it makes sense to disable it. The way this is
designed in SDL, you just have to change one #define, and the entire system
vaporizes out, and SDL functions exactly like it always did. Most of it is
macro magic, so the system is contained to one C file and a few headers.
However, this is on by default and you have to edit a header file to turn it
off. Our hopes is that if we make it easy to disable, but not too easy,
everyone will ultimately be able to get what they want, but we've gently
nudged everyone towards what we think is the best solution.
Emscripten
================================================================================
Build:
$ mkdir build
$ cd build
$ emconfigure ../configure --host=asmjs-unknown-emscripten --disable-assembly --disable-threads --enable-cpuinfo=false CFLAGS="-O2"
$ emmake make
Or with cmake:
$ mkdir build
$ cd build
$ emcmake cmake ..
$ emmake make
To build one of the tests:
$ cd test/
$ emcc -O2 --js-opts 0 -g4 testdraw2.c -I../include ../build/.libs/libSDL2.a ../build/libSDL2_test.a -o a.html
Uses GLES2 renderer or software
tests: https://dl.dropboxusercontent.com/u/17360362/SDL2-em/index.html
Some other SDL2 libraries can be easily built (assuming SDL2 is installed somewhere):
SDL_mixer (http://www.libsdl.org/projects/SDL_mixer/):
$ EMCONFIGURE_JS=1 emconfigure ../configure
build as usual...
SDL_gfx (http://cms.ferzkopp.net/index.php/software/13-sdl-gfx):
$ EMCONFIGURE_JS=1 emconfigure ../configure --disable-mmx
build as usual...
Dollar Gestures
===========================================================================
SDL provides an implementation of the $1 gesture recognition system. This allows for recording, saving, loading, and performing single stroke gestures.
Gestures can be performed with any number of fingers (the centroid of the fingers must follow the path of the gesture), but the number of fingers must be constant (a finger cannot go down in the middle of a gesture). The path of a gesture is considered the path from the time when the final finger went down, to the first time any finger comes up.
Dollar gestures are assigned an Id based on a hash function. This is guaranteed to remain constant for a given gesture. There is a (small) chance that two different gestures will be assigned the same ID. In this case, simply re-recording one of the gestures should result in a different ID.
Recording:
----------
To begin recording on a touch device call:
SDL_RecordGesture(SDL_TouchID touchId), where touchId is the id of the touch device you wish to record on, or -1 to record on all connected devices.
Recording terminates as soon as a finger comes up. Recording is acknowledged by an SDL_DOLLARRECORD event.
A SDL_DOLLARRECORD event is a dgesture with the following fields:
* event.dgesture.touchId - the Id of the touch used to record the gesture.
* event.dgesture.gestureId - the unique id of the recorded gesture.
Performing:
-----------
As long as there is a dollar gesture assigned to a touch, every finger-up event will also cause an SDL_DOLLARGESTURE event with the following fields:
* event.dgesture.touchId - the Id of the touch which performed the gesture.
* event.dgesture.gestureId - the unique id of the closest gesture to the performed stroke.
* event.dgesture.error - the difference between the gesture template and the actual performed gesture. Lower error is a better match.
* event.dgesture.numFingers - the number of fingers used to draw the stroke.
Most programs will want to define an appropriate error threshold and check to be sure that the error of a gesture is not abnormally high (an indicator that no gesture was performed).
Saving:
-------
To save a template, call SDL_SaveDollarTemplate(gestureId, dst) where gestureId is the id of the gesture you want to save, and dst is an SDL_RWops pointer to the file where the gesture will be stored.
To save all currently loaded templates, call SDL_SaveAllDollarTemplates(dst) where dst is an SDL_RWops pointer to the file where the gesture will be stored.
Both functions return the number of gestures successfully saved.
Loading:
--------
To load templates from a file, call SDL_LoadDollarTemplates(touchId,src) where touchId is the id of the touch to load to (or -1 to load to all touch devices), and src is an SDL_RWops pointer to a gesture save file.
SDL_LoadDollarTemplates returns the number of templates successfully loaded.
===========================================================================
Multi Gestures
===========================================================================
SDL provides simple support for pinch/rotate/swipe gestures.
Every time a finger is moved an SDL_MULTIGESTURE event is sent with the following fields:
* event.mgesture.touchId - the Id of the touch on which the gesture was performed.
* event.mgesture.x - the normalized x coordinate of the gesture. (0..1)
* event.mgesture.y - the normalized y coordinate of the gesture. (0..1)
* event.mgesture.dTheta - the amount that the fingers rotated during this motion.
* event.mgesture.dDist - the amount that the fingers pinched during this motion.
* event.mgesture.numFingers - the number of fingers used in the gesture.
===========================================================================
Notes
===========================================================================
For a complete example see test/testgesture.c
Please direct questions/comments to:
jim.tla+sdl_touch@gmail.com
Mercurial
=========
The latest development version of SDL is available via Mercurial.
Mercurial allows you to get up-to-the-minute fixes and enhancements;
as a developer works on a source tree, you can use "hg" to mirror that
source tree instead of waiting for an official release. Please look
at the Mercurial website ( http://mercurial.selenic.com/ ) for more
information on using hg, where you can also download software for
Mac OS X, Windows, and Unix systems.
hg clone http://hg.libsdl.org/SDL
If you are building SDL with an IDE, you will need to copy the file
include/SDL_config.h.default to include/SDL_config.h before building.
If you are building SDL via configure, you will need to run autogen.sh
before running configure.
There is a web interface to the subversion repository at:
http://hg.libsdl.org/SDL/
There is an RSS feed available at that URL, for those that want to
track commits in real time.
iOS
======
==============================================================================
Building the Simple DirectMedia Layer for iOS 5.1+
==============================================================================
Requirements: Mac OS X 10.8 or later and the iOS 7+ SDK.
Instructions:
1. Open SDL.xcodeproj (located in Xcode-iOS/SDL) in Xcode.
2. Select your desired target, and hit build.
There are three build targets:
- libSDL.a:
Build SDL as a statically linked library
- testsdl:
Build a test program (there are known test failures which are fine)
- Template:
Package a project template together with the SDL for iPhone static libraries and copies of the SDL headers. The template includes proper references to the SDL library and headers, skeleton code for a basic SDL program, and placeholder graphics for the application icon and startup screen.
==============================================================================
Build SDL for iOS from the command line
==============================================================================
1. cd (PATH WHERE THE SDL CODE IS)/build-scripts
2. ./iosbuild.sh
If everything goes fine, you should see a build/ios directory, inside there's
two directories "lib" and "include".
"include" contains a copy of the SDL headers that you'll need for your project,
make sure to configure XCode to look for headers there.
"lib" contains find two files, libSDL2.a and libSDL2main.a, you have to add both
to your XCode project. These libraries contain three architectures in them,
armv6 for legacy devices, armv7, and i386 (for the simulator).
By default, iosbuild.sh will autodetect the SDK version you have installed using
xcodebuild -showsdks, and build for iOS >= 3.0, you can override this behaviour
by setting the MIN_OS_VERSION variable, ie:
MIN_OS_VERSION=4.2 ./iosbuild.sh
==============================================================================
Using the Simple DirectMedia Layer for iOS
==============================================================================
FIXME: This needs to be updated for the latest methods
Here is the easiest method:
1. Build the SDL library (libSDL2.a) and the iPhone SDL Application template.
2. Install the iPhone SDL Application template by copying it to one of Xcode's template directories. I recommend creating a directory called "SDL" in "/Developer/Platforms/iOS.platform/Developer/Library/Xcode/Project Templates/" and placing it there.
3. Start a new project using the template. The project should be immediately ready for use with SDL.
Here is a more manual method:
1. Create a new iOS view based application.
2. Build the SDL static library (libSDL2.a) for iOS and include them in your project. Xcode will ignore the library that is not currently of the correct architecture, hence your app will work both on iOS and in the iOS Simulator.
3. Include the SDL header files in your project.
4. Remove the ApplicationDelegate.h and ApplicationDelegate.m files -- SDL for iOS provides its own UIApplicationDelegate. Remove MainWindow.xib -- SDL for iOS produces its user interface programmatically.
5. Delete the contents of main.m and program your app as a regular SDL program instead. You may replace main.m with your own main.c, but you must tell Xcode not to use the project prefix file, as it includes Objective-C code.
==============================================================================
Notes -- Retina / High-DPI and window sizes
==============================================================================
Window and display mode sizes in SDL are in "screen coordinates" (or "points",
in Apple's terminology) rather than in pixels. On iOS this means that a window
created on an iPhone 6 will have a size in screen coordinates of 375 x 667,
rather than a size in pixels of 750 x 1334. All iOS apps are expected to
size their content based on screen coordinates / points rather than pixels,
as this allows different iOS devices to have different pixel densities
(Retina versus non-Retina screens, etc.) without apps caring too much.
By default SDL will not use the full pixel density of the screen on
Retina/high-dpi capable devices. Use the SDL_WINDOW_ALLOW_HIGHDPI flag when
creating your window to enable high-dpi support.
When high-dpi support is enabled, SDL_GetWindowSize and display mode sizes
will still be in "screen coordinates" rather than pixels, but the window will
have a much greater pixel density when the device supports it, and the
SDL_GL_GetDrawableSize or SDL_GetRendererOutputSize functions (depending on
whether raw OpenGL or the SDL_Render API is used) can be queried to determine
the size in pixels of the drawable screen framebuffer.
Some OpenGL ES functions such as glViewport expect sizes in pixels rather than
sizes in screen coordinates. When doing 2D rendering with OpenGL ES, an
orthographic projection matrix using the size in screen coordinates
(SDL_GetWindowSize) can be used in order to display content at the same scale
no matter whether a Retina device is used or not.
==============================================================================
Notes -- Application events
==============================================================================
On iOS the application goes through a fixed life cycle and you will get
notifications of state changes via application events. When these events
are delivered you must handle them in an event callback because the OS may
not give you any processing time after the events are delivered.
e.g.
int HandleAppEvents(void *userdata, SDL_Event *event)
{
switch (event->type)
{
case SDL_APP_TERMINATING:
/* Terminate the app.
Shut everything down before returning from this function.
*/
return 0;
case SDL_APP_LOWMEMORY:
/* You will get this when your app is paused and iOS wants more memory.
Release as much memory as possible.
*/
return 0;
case SDL_APP_WILLENTERBACKGROUND:
/* Prepare your app to go into the background. Stop loops, etc.
This gets called when the user hits the home button, or gets a call.
*/
return 0;
case SDL_APP_DIDENTERBACKGROUND:
/* This will get called if the user accepted whatever sent your app to the background.
If the user got a phone call and canceled it, you'll instead get an SDL_APP_DIDENTERFOREGROUND event and restart your loops.
When you get this, you have 5 seconds to save all your state or the app will be terminated.
Your app is NOT active at this point.
*/
return 0;
case SDL_APP_WILLENTERFOREGROUND:
/* This call happens when your app is coming back to the foreground.
Restore all your state here.
*/
return 0;
case SDL_APP_DIDENTERFOREGROUND:
/* Restart your loops here.
Your app is interactive and getting CPU again.
*/
return 0;
default:
/* No special processing, add it to the event queue */
return 1;
}
}
int main(int argc, char *argv[])
{
SDL_SetEventFilter(HandleAppEvents, NULL);
... run your main loop
return 0;
}
==============================================================================
Notes -- Accelerometer as Joystick
==============================================================================
SDL for iPhone supports polling the built in accelerometer as a joystick device. For an example on how to do this, see the accelerometer.c in the demos directory.
The main thing to note when using the accelerometer with SDL is that while the iPhone natively reports accelerometer as floating point values in units of g-force, SDL_JoystickGetAxis reports joystick values as signed integers. Hence, in order to convert between the two, some clamping and scaling is necessary on the part of the iPhone SDL joystick driver. To convert SDL_JoystickGetAxis reported values BACK to units of g-force, simply multiply the values by SDL_IPHONE_MAX_GFORCE / 0x7FFF.
==============================================================================
Notes -- OpenGL ES
==============================================================================
Your SDL application for iOS uses OpenGL ES for video by default.
OpenGL ES for iOS supports several display pixel formats, such as RGBA8 and RGB565, which provide a 32 bit and 16 bit color buffer respectively. By default, the implementation uses RGB565, but you may use RGBA8 by setting each color component to 8 bits in SDL_GL_SetAttribute.
If your application doesn't use OpenGL's depth buffer, you may find significant performance improvement by setting SDL_GL_DEPTH_SIZE to 0.
Finally, if your application completely redraws the screen each frame, you may find significant performance improvement by setting the attribute SDL_GL_RETAINED_BACKING to 0.
OpenGL ES on iOS doesn't use the traditional system-framebuffer setup provided in other operating systems. Special care must be taken because of this:
- The drawable Renderbuffer must be bound to the GL_RENDERBUFFER binding point when SDL_GL_SwapWindow is called.
- The drawable Framebuffer Object must be bound while rendering to the screen and when SDL_GL_SwapWindow is called.
- If multisample antialiasing (MSAA) is used and glReadPixels is used on the screen, the drawable framebuffer must be resolved to the MSAA resolve framebuffer (via glBlitFramebuffer or glResolveMultisampleFramebufferAPPLE), and the MSAA resolve framebuffer must be bound to the GL_READ_FRAMEBUFFER binding point, before glReadPixels is called.
The above objects can be obtained via SDL_GetWindowWMInfo (in SDL_syswm.h).
==============================================================================
Notes -- Keyboard
==============================================================================
The SDL keyboard API has been extended to support on-screen keyboards:
void SDL_StartTextInput()
-- enables text events and reveals the onscreen keyboard.
void SDL_StopTextInput()
-- disables text events and hides the onscreen keyboard.
SDL_bool SDL_IsTextInputActive()
-- returns whether or not text events are enabled (and the onscreen keyboard is visible)
==============================================================================
Notes -- Reading and Writing files
==============================================================================
Each application installed on iPhone resides in a sandbox which includes its own Application Home directory. Your application may not access files outside this directory.
Once your application is installed its directory tree looks like:
MySDLApp Home/
MySDLApp.app
Documents/
Library/
Preferences/
tmp/
When your SDL based iPhone application starts up, it sets the working directory to the main bundle (MySDLApp Home/MySDLApp.app), where your application resources are stored. You cannot write to this directory. Instead, I advise you to write document files to "../Documents/" and preferences to "../Library/Preferences".
More information on this subject is available here:
http://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/Introduction/Introduction.html
==============================================================================
Notes -- iPhone SDL limitations
==============================================================================
Windows:
Full-size, single window applications only. You cannot create multi-window SDL applications for iPhone OS. The application window will fill the display, though you have the option of turning on or off the menu-bar (pass SDL_CreateWindow the flag SDL_WINDOW_BORDERLESS).
Textures:
The optimal texture formats on iOS are SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_BGR888, and SDL_PIXELFORMAT_RGB24 pixel formats.
Loading Shared Objects:
This is disabled by default since it seems to break the terms of the iOS SDK agreement for iOS versions prior to iOS 8. It can be re-enabled in SDL_config_iphoneos.h.
==============================================================================
Game Center
==============================================================================
Game Center integration might require that you break up your main loop in order to yield control back to the system. In other words, instead of running an endless main loop, you run each frame in a callback function, using:
int SDL_iPhoneSetAnimationCallback(SDL_Window * window, int interval, void (*callback)(void*), void *callbackParam);
This will set up the given function to be called back on the animation callback, and then you have to return from main() to let the Cocoa event loop run.
e.g.
extern "C"
void ShowFrame(void*)
{
... do event handling, frame logic and rendering ...
}
int main(int argc, char *argv[])
{
... initialize game ...
#if __IPHONEOS__
// Initialize the Game Center for scoring and matchmaking
InitGameCenter();
// Set up the game to run in the window animation callback on iOS
// so that Game Center and so forth works correctly.
SDL_iPhoneSetAnimationCallback(window, 1, ShowFrame, NULL);
#else
while ( running ) {
ShowFrame(0);
DelayFrame();
}
#endif
return 0;
}
Linux
================================================================================
By default SDL will only link against glibc, the rest of the features will be
enabled dynamically at runtime depending on the available features on the target
system. So, for example if you built SDL with Xinerama support and the target
system does not have the Xinerama libraries installed, it will be disabled
at runtime, and you won't get a missing library error, at least with the
default configuration parameters.
================================================================================
Build Dependencies
================================================================================
Ubuntu 13.04, all available features enabled:
sudo apt-get install build-essential mercurial make cmake autoconf automake \
libtool libasound2-dev libpulse-dev libaudio-dev libx11-dev libxext-dev \
libxrandr-dev libxcursor-dev libxi-dev libxinerama-dev libxxf86vm-dev \
libxss-dev libgl1-mesa-dev libesd0-dev libdbus-1-dev libudev-dev \
libgles1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libibus-1.0-dev
Ubuntu 14.04 can also add "libwayland-dev libmirclient-dev libxkbcommon-dev"
to that command line for Wayland and Mir support.
NOTES:
- This includes all the audio targets except arts, because Ubuntu pulled the
artsc0-dev package, but in theory SDL still supports it.
- DirectFB isn't included because the configure script (currently) fails to find
it at all. You can do "sudo apt-get install libdirectfb-dev" and fix the
configure script to include DirectFB support. Send patches. :)
================================================================================
Joystick does not work
================================================================================
If you compiled or are using a version of SDL with udev support (and you should!)
there's a few issues that may cause SDL to fail to detect your joystick. To
debug this, start by installing the evtest utility. On Ubuntu/Debian:
sudo apt-get install evtest
Then run:
sudo evtest
You'll hopefully see your joystick listed along with a name like "/dev/input/eventXX"
Now run:
cat /dev/input/event/XX
If you get a permission error, you need to set a udev rule to change the mode of
your device (see below)
Also, try:
sudo udevadm info --query=all --name=input/eventXX
If you see a line stating ID_INPUT_JOYSTICK=1, great, if you don't see it,
you need to set up an udev rule to force this variable.
A combined rule for the Saitek Pro Flight Rudder Pedals to fix both issues looks
like:
SUBSYSTEM=="input", ATTRS{idProduct}=="0763", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
SUBSYSTEM=="input", ATTRS{idProduct}=="0764", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
You can set up similar rules for your device by changing the values listed in
idProduct and idVendor. To obtain these values, try:
sudo udevadm info -a --name=input/eventXX | grep idVendor
sudo udevadm info -a --name=input/eventXX | grep idProduct
If multiple values come up for each of these, the one you want is the first one of each.
On other systems which ship with an older udev (such as CentOS), you may need
to set up a rule such as:
SUBSYSTEM=="input", ENV{ID_CLASS}=="joystick", ENV{ID_INPUT_JOYSTICK}="1"
Mac OS X
==============================================================================
These instructions are for people using Apple's Mac OS X (pronounced
"ten").
From the developer's point of view, OS X is a sort of hybrid Mac and
Unix system, and you have the option of using either traditional
command line tools or Apple's IDE Xcode.
To build SDL using the command line, use the standard configure and make
process:
./configure
make
sudo make install
You can also build SDL as a Universal library (a single binary for both
32-bit and 64-bit Intel architectures), on Mac OS X 10.7 and newer, by using
the gcc-fat.sh script in build-scripts:
mkdir mybuild
cd mybuild
CC=$PWD/../build-scripts/gcc-fat.sh CXX=$PWD/../build-scripts/g++fat.sh ../configure
make
sudo make install
This script builds SDL with 10.5 ABI compatibility on i386 and 10.6
ABI compatibility on x86_64 architectures. For best compatibility you
should compile your application the same way.
Please note that building SDL requires at least Xcode 4.6 and the 10.7 SDK
(even if you target back to 10.5 systems). PowerPC support for Mac OS X has
been officially dropped as of SDL 2.0.2.
To use the library once it's built, you essential have two possibilities:
use the traditional autoconf/automake/make method, or use Xcode.
==============================================================================
Caveats for using SDL with Mac OS X
==============================================================================
Some things you have to be aware of when using SDL on Mac OS X:
- If you register your own NSApplicationDelegate (using [NSApp setDelegate:]),
SDL will not register its own. This means that SDL will not terminate using
SDL_Quit if it receives a termination request, it will terminate like a
normal app, and it will not send a SDL_DROPFILE when you request to open a
file with the app. To solve these issues, put the following code in your
NSApplicationDelegate implementation:
- (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender
{
if (SDL_GetEventState(SDL_QUIT) == SDL_ENABLE) {
SDL_Event event;
event.type = SDL_QUIT;
SDL_PushEvent(&event);
}
return NSTerminateCancel;
}
- (BOOL)application:(NSApplication *)theApplication openFile:(NSString *)filename
{
if (SDL_GetEventState(SDL_DROPFILE) == SDL_ENABLE) {
SDL_Event event;
event.type = SDL_DROPFILE;
event.drop.file = SDL_strdup([filename UTF8String]);
return (SDL_PushEvent(&event) > 0);
}
return NO;
}
==============================================================================
Using the Simple DirectMedia Layer with a traditional Makefile
==============================================================================
An existing autoconf/automake build system for your SDL app has good chances
to work almost unchanged on OS X. However, to produce a "real" Mac OS X binary
that you can distribute to users, you need to put the generated binary into a
so called "bundle", which basically is a fancy folder with a name like
"MyCoolGame.app".
To get this build automatically, add something like the following rule to
your Makefile.am:
bundle_contents = APP_NAME.app/Contents
APP_NAME_bundle: EXE_NAME
mkdir -p $(bundle_contents)/MacOS
mkdir -p $(bundle_contents)/Resources
echo "APPL????" > $(bundle_contents)/PkgInfo
$(INSTALL_PROGRAM) $< $(bundle_contents)/MacOS/
You should replace EXE_NAME with the name of the executable. APP_NAME is what
will be visible to the user in the Finder. Usually it will be the same
as EXE_NAME but capitalized. E.g. if EXE_NAME is "testgame" then APP_NAME
usually is "TestGame". You might also want to use @PACKAGE@ to use the package
name as specified in your configure.in file.
If your project builds more than one application, you will have to do a bit
more. For each of your target applications, you need a separate rule.
If you want the created bundles to be installed, you may want to add this
rule to your Makefile.am:
install-exec-hook: APP_NAME_bundle
rm -rf $(DESTDIR)$(prefix)/Applications/APP_NAME.app
mkdir -p $(DESTDIR)$(prefix)/Applications/
cp -r $< /$(DESTDIR)$(prefix)Applications/
This rule takes the Bundle created by the rule from step 3 and installs them
into $(DESTDIR)$(prefix)/Applications/.
Again, if you want to install multiple applications, you will have to augment
the make rule accordingly.
But beware! That is only part of the story! With the above, you end up with
a bare bone .app bundle, which is double clickable from the Finder. But
there are some more things you should do before shipping your product...
1) The bundle right now probably is dynamically linked against SDL. That
means that when you copy it to another computer, *it will not run*,
unless you also install SDL on that other computer. A good solution
for this dilemma is to static link against SDL. On OS X, you can
achieve that by linking against the libraries listed by
sdl-config --static-libs
instead of those listed by
sdl-config --libs
Depending on how exactly SDL is integrated into your build systems, the
way to achieve that varies, so I won't describe it here in detail
2) Add an 'Info.plist' to your application. That is a special XML file which
contains some meta-information about your application (like some copyright
information, the version of your app, the name of an optional icon file,
and other things). Part of that information is displayed by the Finder
when you click on the .app, or if you look at the "Get Info" window.
More information about Info.plist files can be found on Apple's homepage.
As a final remark, let me add that I use some of the techniques (and some
variations of them) in Exult and ScummVM; both are available in source on
the net, so feel free to take a peek at them for inspiration!
==============================================================================
Using the Simple DirectMedia Layer with Xcode
==============================================================================
These instructions are for using Apple's Xcode IDE to build SDL applications.
- First steps
The first thing to do is to unpack the Xcode.tar.gz archive in the
top level SDL directory (where the Xcode.tar.gz archive resides).
Because Stuffit Expander will unpack the archive into a subdirectory,
you should unpack the archive manually from the command line:
cd [path_to_SDL_source]
tar zxf Xcode.tar.gz
This will create a new folder called Xcode, which you can browse
normally from the Finder.
- Building the Framework
The SDL Library is packaged as a framework bundle, an organized
relocatable folder hierarchy of executable code, interface headers,
and additional resources. For practical purposes, you can think of a
framework as a more user and system-friendly shared library, whose library
file behaves more or less like a standard UNIX shared library.
To build the framework, simply open the framework project and build it.
By default, the framework bundle "SDL.framework" is installed in
/Library/Frameworks. Therefore, the testers and project stationary expect
it to be located there. However, it will function the same in any of the
following locations:
~/Library/Frameworks
/Local/Library/Frameworks
/System/Library/Frameworks
- Build Options
There are two "Build Styles" (See the "Targets" tab) for SDL.
"Deployment" should be used if you aren't tweaking the SDL library.
"Development" should be used to debug SDL apps or the library itself.
- Building the Testers
Open the SDLTest project and build away!
- Using the Project Stationary
Copy the stationary to the indicated folders to access it from
the "New Project" and "Add target" menus. What could be easier?
- Setting up a new project by hand
Some of you won't want to use the Stationary so I'll give some tips:
* Create a new "Cocoa Application"
* Add src/main/macosx/SDLMain.m , .h and .nib to your project
* Remove "main.c" from your project
* Remove "MainMenu.nib" from your project
* Add "$(HOME)/Library/Frameworks/SDL.framework/Headers" to include path
* Add "$(HOME)/Library/Frameworks" to the frameworks search path
* Add "-framework SDL -framework Foundation -framework AppKit" to "OTHER_LDFLAGS"
* Set the "Main Nib File" under "Application Settings" to "SDLMain.nib"
* Add your files
* Clean and build
- Building from command line
Use pbxbuild in the same directory as your .pbproj file
- Running your app
You can send command line args to your app by either invoking it from
the command line (in *.app/Contents/MacOS) or by entering them in the
"Executables" panel of the target settings.
- Implementation Notes
Some things that may be of interest about how it all works...
* Working directory
As defined in the SDL_main.m file, the working directory of your SDL app
is by default set to its parent. You may wish to change this to better
suit your needs.
* You have a Cocoa App!
Your SDL app is essentially a Cocoa application. When your app
starts up and the libraries finish loading, a Cocoa procedure is called,
which sets up the working directory and calls your main() method.
You are free to modify your Cocoa app with generally no consequence
to SDL. You cannot, however, easily change the SDL window itself.
Functionality may be added in the future to help this.
Known bugs are listed in the file "BUGS"
Native Client
================================================================================
Requirements:
* Native Client SDK (https://developer.chrome.com/native-client),
(tested with Pepper version 33 or higher).
The SDL backend for Chrome's Native Client has been tested only with the PNaCl
toolchain, which generates binaries designed to run on ARM and x86_32/64
platforms. This does not mean it won't work with the other toolchains!
================================================================================
Building SDL for NaCl
================================================================================
Set up the right environment variables (see naclbuild.sh), then configure SDL with:
configure --host=pnacl --prefix some/install/destination
Then "make".
As an example of how to create a deployable app a Makefile project is provided
in test/nacl/Makefile, which includes some monkey patching of the common.mk file
provided by NaCl, without which linking properly to SDL won't work (the search
path can't be modified externally, so the linker won't find SDL's binaries unless
you dump them into the SDK path, which is inconvenient).
Also provided in test/nacl is the required support file, such as index.html,
manifest.json, etc.
SDL apps for NaCl run on a worker thread using the ppapi_simple infrastructure.
This allows for blocking calls on all the relevant systems (OpenGL ES, filesystem),
hiding the asynchronous nature of the browser behind the scenes...which is not the
same as making it disappear!
================================================================================
Running tests
================================================================================
Due to the nature of NaCl programs, building and running SDL tests is not as
straightforward as one would hope. The script naclbuild.sh in build-scripts
automates the process and should serve as a guide for users of SDL trying to build
their own applications.
Basic usage:
./naclbuild.sh path/to/pepper/toolchain (i.e. ~/naclsdk/pepper_35)
This will build testgles2.c by default.
If you want to build a different test, for example testrendercopyex.c:
SOURCES=~/sdl/SDL/test/testrendercopyex.c ./naclbuild.sh ~/naclsdk/pepper_35
Once the build finishes, you have to serve the contents with a web server (the
script will give you instructions on how to do that with Python).
================================================================================
RWops and nacl_io
================================================================================
SDL_RWops work transparently with nacl_io. Two functions control the mount points:
int mount(const char* source, const char* target,
const char* filesystemtype,
unsigned long mountflags, const void *data);
int umount(const char *target);
For convenience, SDL will by default mount an httpfs tree at / before calling
the app's main function. Such setting can be overridden by calling:
umount("/");
And then mounting a different filesystem at /
It's important to consider that the asynchronous nature of file operations on a
browser is hidden from the application, effectively providing the developer with
a set of blocking file operations just like you get in a regular desktop
environment, which eases the job of porting to Native Client, but also introduces
a set of challenges of its own, in particular when big file sizes and slow
connections are involved.
For more information on how nacl_io and mount points work, see:
https://developer.chrome.com/native-client/devguide/coding/nacl_io
https://src.chromium.org/chrome/trunk/src/native_client_sdk/src/libraries/nacl_io/nacl_io.h
To be able to save into the directory "/save/" (like backup of game) :
mount("", "/save", "html5fs", 0, "type=PERSISTENT");
And add to manifest.json :
"permissions": [
"unlimitedStorage"
]
================================================================================
TODO - Known Issues
================================================================================
* Testing of all systems with a real application (something other than SDL's tests)
* Key events don't seem to work properly
Pandora
=====================================================================
( http://openpandora.org/ )
- A pandora specific video driver was written to allow SDL 2.0 with OpenGL ES
support to work on the pandora under the framebuffer. This driver do not have
input support for now, so if you use it you will have to add your own control code.
The video driver name is "pandora" so if you have problem running it from
the framebuffer, try to set the following variable before starting your application :
"export SDL_VIDEODRIVER=pandora"
- OpenGL ES support was added to the x11 driver, so it's working like the normal
x11 driver one with OpenGLX support, with SDL input event's etc..
David Carré (Cpasjuste)
cpasjuste@gmail.com
Platforms
=========
We maintain the list of supported platforms on our wiki now, and how to
build and install SDL for those platforms:
https://wiki.libsdl.org/Installation
Porting
=======
* Porting To A New Platform
The first thing you have to do when porting to a new platform, is look at
include/SDL_platform.h and create an entry there for your operating system.
The standard format is __PLATFORM__, where PLATFORM is the name of the OS.
Ideally SDL_platform.h will be able to auto-detect the system it's building
on based on C preprocessor symbols.
There are two basic ways of building SDL at the moment:
1. The "UNIX" way: ./configure; make; make install
If you have a GNUish system, then you might try this. Edit configure.in,
take a look at the large section labelled:
"Set up the configuration based on the host platform!"
Add a section for your platform, and then re-run autogen.sh and build!
2. Using an IDE:
If you're using an IDE or other non-configure build system, you'll probably
want to create a custom SDL_config.h for your platform. Edit SDL_config.h,
add a section for your platform, and create a custom SDL_config_{platform}.h,
based on SDL_config.h.minimal and SDL_config.h.in
Add the top level include directory to the header search path, and then add
the following sources to the project:
src/*.c
src/atomic/*.c
src/audio/*.c
src/cpuinfo/*.c
src/events/*.c
src/file/*.c
src/haptic/*.c
src/joystick/*.c
src/power/*.c
src/render/*.c
src/stdlib/*.c
src/thread/*.c
src/timer/*.c
src/video/*.c
src/audio/disk/*.c
src/audio/dummy/*.c
src/filesystem/dummy/*.c
src/video/dummy/*.c
src/haptic/dummy/*.c
src/joystick/dummy/*.c
src/main/dummy/*.c
src/thread/generic/*.c
src/timer/dummy/*.c
src/loadso/dummy/*.c
Once you have a working library without any drivers, you can go back to each
of the major subsystems and start implementing drivers for your platform.
If you have any questions, don't hesitate to ask on the SDL mailing list:
http://www.libsdl.org/mailing-list.php
Enjoy!
Sam Lantinga (slouken@libsdl.org)
PSP
======
SDL port for the Sony PSP contributed by
Captian Lex
Credit to
Marcus R.Brown,Jim Paris,Matthew H for the original SDL 1.2 for PSP
Geecko for his PSP GU lib "Glib2d"
Building
--------
To build for the PSP, make sure psp-config is in the path and run:
make -f Makefile.psp
To Do
------
PSP Screen Keyboard
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment