Hello Sam,
while profiling ScummVM I noticed it was making use of the generic
BlitNToN blitter, which struck me as odd because it should be a very
classical codepath.
After investigating, I saw that in the blit op chooser:
{ 0x0000F800,0x000007E0,0x0000001F, 4, 0x00FF0000,0x0000FF00,0x000000FF,
0, NULL, Blit_RGB565_ARGB8888, SET_ALPHA },
{ 0x0000F800,0x000007E0,0x0000001F, 4, 0x000000FF,0x0000FF00,0x00FF0000,
0, NULL, Blit_RGB565_ABGR8888, SET_ALPHA },
{ 0x0000F800,0x000007E0,0x0000001F, 4, 0xFF000000,0x00FF0000,0x0000FF00,
0, NULL, Blit_RGB565_RGBA8888, SET_ALPHA },
{ 0x0000F800,0x000007E0,0x0000001F, 4, 0x0000FF00,0x00FF0000,0xFF000000,
0, NULL, Blit_RGB565_BGRA8888, SET_ALPHA },
Couldn't the optimized versions be used for NO_ALPHA too? I take it
that the resulting alpha component can be undefined as it should never
be used.
I tried this (see attached patch) and it worked perfectly (and
therefore faster) on ScummVM but there might be a trick (I'm not
expert at the semantics of SDL, ie NO_ALPHA, SET_ALPHA and COPY_ALPHA
there).
What do you think?
Cheers,
Bertrand
Brad Smith 2012-08-01 20:10:19 PDT
The attached patch from the OpenBSD ports tree is to increase the number of
uhid devices to scan for joysticks. It's somewhat easy to exhaust the default
number of devices which are scanned.
Matthias Bentrup 2012-08-09 12:53:17 PDT
With OpenGL 4.3 the ARB added a new context flag for context reset isolation
and renamed the existing ES2 profile bit to ES profile bit, as it can be used
to request GLES 3 compatible contexts, too.
This patch adds these changes to SDL on Linux and Windows.
Also SDL lacks the ability to create shared contexts. This patch also adds a
new GL attribute to enable context sharing. As casting a GL context to int is
not portable, I added only a boolean attribute
SDL_GL_SHARE_WITH_CURRENT_CONTEXT, which makes the new context share resources
with the context current on the creating thread.
I think you'll need to install Xquartz, the external-but-official replacement
for Apple's X11, to get the Xlib headers: http://support.apple.com/kb/HT5293
This required a small public API change: SDL_GL_SetSwapInterval() now accepts
negative values, and SDL_GL_GetSwapInterval() doesn't report errors anymore
(if it can't work, it'll return zero as a reasonable default).
If you need to test for errors, such as a lack of swap_control_tear support,
check the results of SDL_GL_SetSwapInterval() when you set your desired
value.
