Scott Percival 2011-07-03 06:41:51 PDT
This submission is aimed at making life easier for OpenGL ES capable devices
running a X11 stack (e.g. Maemo, Meego, TrimSlice, other ARM SoC boards not
running Android). SDL's Pandora support already has the neccesary GLES-to-X11
glue code, however it's all ghetto'd off in Makefile.pandora and not very
flexible.
The patch:
- adds an awesome --enable-video-opengles option to configure
- re-modifies the opengles and opengles2 SDL_renderers to use function pointers
- no idea why this was removed?
- for SDL_Renderers, links in libGLESv1_CM, libGLES_CM (for PowerVR fans) or
libGLESv2 at runtime
- links in libEGL.so at runtime - the old code made an assumption that
eglFunctions could be pulled from the active GLES library, PowerVR for one
doesn't let you do that with their libGLESv2
- allows you to pick which of GLES v1 or v2 to load via
SDL_GL_CONTEXT_MAJOR_VERSION
So far I've tested this on a Nokia N900 (OMAP 3430/SGX 530 running Maemo 5) and
a Toshiba AC100 (Tegra 2 running Ubuntu 10.10). I haven't tested it on... well,
everything that isn't those two, such as a Pandora, iOS or Android device. The
Pandora specific code should be kept intact (fingers crossed), and nothing
painfully drastic has been added to the SDL_renderers. The library loading
sequence in SDL_x11opengles has been updated to accomodate both NVIDIA's
propensity to let developers get away with murder and PowerVR's alternative of
punishing every missed step.
The test apps work okay with GLES or GLES2 as the renderer. For some reason
alpha blending doesn't seem to work on the Tegra 2; last week NVIDIA pushed out
a new set of X11 GLES drivers, so I'll try and investigate once I upgrade
those. Also, this patch adds things to configure.in, include/SDL_config.h.in
and test/configure.in. I didn't know what the policy was re. committing
generated spaghetti from autotools, so ./autogen.sh has to be run again. Sorry.
I think that's about everything, let me know if there's anything I've
overlooked.
Matej 2009-01-08 09:25:34 PST
Hello,
I maintain a cross-platform project that uses SDL.
One of the users who runs OSX has told me that he has problems with linking to
SDL due to missing -framework option.
I think that the problem is because of this:
'sdl-config --libs' outputs '-L/opt/local/lib -lSDLmain -lSDL
-Wl,-framework,Cocoa'
All the options are passed to the linker except the last one. I think that the
good output should be just:
'-L/opt/local/lib -lSDLmain -lSDL -framework Cocoa'
since those options (--libs) are passed to the linker, so the '-Wl' option is
redundant and possibly harmful in this very case
I use autotools with libtool to do the build...
Regards,
Matej
From: "Mike Gorchak"
Subject: Re: About QNX support in SDL 1.3
Here is another batch of patches.
1) Makefile.in - added SDL_opengles.h header as header to install.
2) configure.in - Added special define to detect Common Lite OpenGL ES
library in case if Common library is not installed. Added check for
clock_gettime in libc (in QNX it is in libc).
3) SDL_config.h.in - Added SDL_VIDEO_RENDER_OPENGL_ES and
SDL_VIDEO_OPENGL_ES declarations for configure script autodetection.
4) SDL_opengles.h - Added GL_API definition if it is not defined. Added
extension GL_OES_draw_texture because OpenGL ES Renderer uses it without
declaration. Added GL_OES_vertex_buffer_object extension, which is supported
under QNX OpenGL ES. Added GL_OES_single_precision extension.
5) To the test directory I've added building OpenGL ES test applications
through the autotools suite. Was support for iPhone IDE building only.
From the autoconf obsolete macros documentation:
Macro: AC_CANONICAL_SYSTEM
Determine the system type and set output variables to the names of the canonical system types. See section Getting the Canonical System Type, for details about the variables this macro sets.
The user is encouraged to use either AC_CANONICAL_BUILD, or AC_CANONICAL_HOST, or AC_CANONICAL_TARGET, depending on the needs. Using AC_CANONICAL_TARGET is enough to run the two other macros.
From the documentation for the canonical environments:
case $target in
i386-*-mach* | i386-*-gnu*)
obj_format=aout emulation=mach bfd_gas=yes ;;
i960-*-bout) obj_format=bout ;;
esac
Note that the above example uses $target because it's taken from a tool which can be built on some architecture ($build), run on another ($host), but yet handle data for a third architecture ($target). Such tools are usually part of a compiler suite, they generate code for a specific $target.
However $target should be meaningless for most packages. If you want to base a decision on the system where your program will be run, make sure you use the $host variable.
