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view README.QNX @ 3162:dc1eb82ffdaa
Von: Thomas Zimmermann
Betreff: [SDL] [PATCH] Make static variables const
Datum: Tue, 19 May 2009 19:45:37 +0200
Hi,
this is a set of simple changes which make some of SDL's internal static
arrays constant. The purpose is to shrink the number of write-able
static bytes and thus increase the number of memory pages shared between
SDL applications.
The patch set is against trunk@4513. Each of the attached patch files is
specific to a sub-system. The set is completed by a second mail, because
of the list's 40 KiB limit.
The files readelf-r4513.txt and readelf-const-patch.txt where made by
calling 'readelf -S libSDL.so'. They show the difference in ELF sections
without and with the patch. Some numbers measured on my x86-64:
Before
[13] .rodata PROGBITS 00000000000eaaa0 000eaaa0
0000000000008170 0000000000000000 A 0 0 32
[19] .data.rel.ro PROGBITS 00000000003045e0 001045e0
00000000000023d0 0000000000000000 WA 0 0 32
[23] .data PROGBITS 00000000003076e0 001076e0
0000000000004988 0000000000000000 WA 0 0 32
After
[13] .rodata PROGBITS 00000000000eaaa0 000eaaa0
0000000000009a50 0000000000000000 A 0 0 32
[19] .data.rel.ro PROGBITS 0000000000306040 00106040
0000000000002608 0000000000000000 WA 0 0 32
[23] .data PROGBITS 0000000000309360 00109360
0000000000002e88 0000000000000000 WA 0 0 32
The size of the write-able data section decreased considerably. Some
entries became const-after-relocation, while most of its content went
straight into the read-only data section.
Best regards, Thomas
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 03 Jun 2009 04:37:27 +0000 |
parents | 3cf236d3cd81 |
children | ec126b077b96 |
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README.QNX by Mike Gorchak <mike@malva.ua>, <lestat@i.com.ua> Last changed at 23 Mar 2009. QNX Photon and GF drivers are being constructed. QNX QSA (QNX Sound Architecture) driver is ready. QNX CDROM driver is ready. QNX HID input driver is being constructed. ---------------------- -- SDL QSA driver -- ---------------------- Due to QNX Sound Architecture limitations software could not determine what playback channels are designed for, so some casus can be. For example, output after testmultiaudio test utility execution: Using audio driver: qsa playing on device #0: ('Vortex 8820 @ fb000000 d0')...done. playing on device #1: ('Vortex 8820 @ fb000000 d1')...done. playing on device #2: ('i8x0 @ d800 d0')...done. playing on device #3: ('i8x0 @ d800 d1')...done. playing on all devices... Open device 3 failed: QSA: snd_pcm_channel_params failed: Invalid argument If speakers are connected to both audio cards: Vortex 8820 and Intel Integrated Audio we can hear sound playback on device #0 and devices #2, #3 only. Device #1 is an unknown PCM channel which does not produce any sound. As for error during device #3 opening, it's caused by QSA software mixer channel, because it can't open real hardware device #2, since it's already opened by SDL. After simultaneous sound playback on all devices utility testmultiaudio stays running waiting for sound playback finish on device #1, which is locked up due to some Aureal Vortex 8820 driver limitations. --------------------- -- SDL GF driver -- --------------------- Here is an additional information about SDL GF driver: * 0. Introduction. * 1. Environment variables which SDL GF driver supports. * 2. Custom video modes. * 3. Limitations. 0. Introduction. SDL GF driver is a layer between SDL and QNX Graphics Framework (GF). SDL GF driver also supports OpenGL ES through the QNX Graphics Framework. Hardware accelerated features which SDL can support depend on real hardware capabilities. 1. Environment variables which GF driver supports. GF driver supports the following environment variables for QNX GF specific customization options: a) SDL_VIDEO_GF_REFRESH_RATE - refresh rate of video output in Hz. Without this environment variable declaration SDL controls refresh rate of your display. If this enironment variable is set to 0, SDL will control refresh rate of display, otherwise value of flag SDL_VIDEO_GF_REFRESH_RATE is used for all screen resolutions as refresh rate. This example will set 60Hz refresh rate as refresh rate for all graphics modes: export SDL_VIDEO_GF_REFRESH_RATE=60 2. Custom video modes. Since most QNX graphics drivers support GENERIC video modes, i.e. you can specify any horizontal and vertical resolution and any refresh rate, SDL GF driver uses its own fullscreen modes list, which can be incomplete. You can add any custom video mode, which your QNX graphics driver supports by editing file ./src/video/qnxgf/SDL_qnxgf.c. Custom graphics mode definition looks like this: {0, 1024, 640, 60, NULL}, /* 1024x640 mode is 60Hz only */ You must specify horizontal resolution as the second parameter, vertical resolution as the third one and refresh rate as the fourth parameter. Please leave the first and the last parameters as 0 and NULL. Then send me your changes to e-mail address which is specified in the header of this document. 3. Limitations. There are few limitations while using SDL GF driver: a) Since GF driver supports fullscreen modes only, when flag SDL_WINDOW_FULLSCREEN is not specified, SDL GF driver will try to find the fullscreen graphics mode which corresponds to SDL window size. Refresh rate will be the lowest available, if SDL_VIDEO_GF_REFRESH_RATE environment variable is not set. b) As confirmed by QSSL none of existing video drivers has support of doublescan low-resolution video modes. So modes below 640x480 are not supported. If your video driver supports low-resolution video modes, please add SDL_GF_LOWRESOLUTION flag to the gf_devicename array in the SDL_qnxgf.c source file. ------------------------- -- SDL Photon driver -- ------------------------- ---------------------------- -- SDL HID input driver -- ----------------------------