src/video/dummy/SDL_nullvideo.c
author Ryan C. Gordon <icculus@icculus.org>
Mon, 06 Apr 2015 00:10:54 -0400
changeset 9458 543298b36b28
parent 9444 d0865e9f674a
child 9619 b94b6d0bff0f
permissions -rw-r--r--
This function can be static.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 #include "../../SDL_internal.h"
    22 
    23 #if SDL_VIDEO_DRIVER_DUMMY
    24 
    25 /* Dummy SDL video driver implementation; this is just enough to make an
    26  *  SDL-based application THINK it's got a working video driver, for
    27  *  applications that call SDL_Init(SDL_INIT_VIDEO) when they don't need it,
    28  *  and also for use as a collection of stubs when porting SDL to a new
    29  *  platform for which you haven't yet written a valid video driver.
    30  *
    31  * This is also a great way to determine bottlenecks: if you think that SDL
    32  *  is a performance problem for a given platform, enable this driver, and
    33  *  then see if your application runs faster without video overhead.
    34  *
    35  * Initial work by Ryan C. Gordon (icculus@icculus.org). A good portion
    36  *  of this was cut-and-pasted from Stephane Peter's work in the AAlib
    37  *  SDL video driver.  Renamed to "DUMMY" by Sam Lantinga.
    38  */
    39 
    40 #include "SDL_video.h"
    41 #include "SDL_mouse.h"
    42 #include "../SDL_sysvideo.h"
    43 #include "../SDL_pixels_c.h"
    44 #include "../../events/SDL_events_c.h"
    45 
    46 #include "SDL_nullvideo.h"
    47 #include "SDL_nullevents_c.h"
    48 #include "SDL_nullframebuffer_c.h"
    49 
    50 #define DUMMYVID_DRIVER_NAME "dummy"
    51 
    52 /* Initialization/Query functions */
    53 static int DUMMY_VideoInit(_THIS);
    54 static int DUMMY_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode);
    55 static void DUMMY_VideoQuit(_THIS);
    56 
    57 /* DUMMY driver bootstrap functions */
    58 
    59 static int
    60 DUMMY_Available(void)
    61 {
    62     const char *envr = SDL_getenv("SDL_VIDEODRIVER");
    63     if ((envr) && (SDL_strcmp(envr, DUMMYVID_DRIVER_NAME) == 0)) {
    64         return (1);
    65     }
    66 
    67     return (0);
    68 }
    69 
    70 static void
    71 DUMMY_DeleteDevice(SDL_VideoDevice * device)
    72 {
    73     SDL_free(device);
    74 }
    75 
    76 static SDL_VideoDevice *
    77 DUMMY_CreateDevice(int devindex)
    78 {
    79     SDL_VideoDevice *device;
    80 
    81     /* Initialize all variables that we clean on shutdown */
    82     device = (SDL_VideoDevice *) SDL_calloc(1, sizeof(SDL_VideoDevice));
    83     if (!device) {
    84         SDL_OutOfMemory();
    85         return (0);
    86     }
    87 
    88     /* Set the function pointers */
    89     device->VideoInit = DUMMY_VideoInit;
    90     device->VideoQuit = DUMMY_VideoQuit;
    91     device->SetDisplayMode = DUMMY_SetDisplayMode;
    92     device->PumpEvents = DUMMY_PumpEvents;
    93     device->CreateWindowFramebuffer = SDL_DUMMY_CreateWindowFramebuffer;
    94     device->UpdateWindowFramebuffer = SDL_DUMMY_UpdateWindowFramebuffer;
    95     device->DestroyWindowFramebuffer = SDL_DUMMY_DestroyWindowFramebuffer;
    96 
    97     device->free = DUMMY_DeleteDevice;
    98 
    99     return device;
   100 }
   101 
   102 VideoBootStrap DUMMY_bootstrap = {
   103     DUMMYVID_DRIVER_NAME, "SDL dummy video driver",
   104     DUMMY_Available, DUMMY_CreateDevice
   105 };
   106 
   107 
   108 int
   109 DUMMY_VideoInit(_THIS)
   110 {
   111     SDL_DisplayMode mode;
   112 
   113     /* Use a fake 32-bpp desktop mode */
   114     mode.format = SDL_PIXELFORMAT_RGB888;
   115     mode.w = 1024;
   116     mode.h = 768;
   117     mode.refresh_rate = 0;
   118     mode.driverdata = NULL;
   119     if (SDL_AddBasicVideoDisplay(&mode) < 0) {
   120         return -1;
   121     }
   122 
   123     SDL_zero(mode);
   124     SDL_AddDisplayMode(&_this->displays[0], &mode);
   125 
   126     /* We're done! */
   127     return 0;
   128 }
   129 
   130 static int
   131 DUMMY_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode)
   132 {
   133     return 0;
   134 }
   135 
   136 void
   137 DUMMY_VideoQuit(_THIS)
   138 {
   139 }
   140 
   141 #endif /* SDL_VIDEO_DRIVER_DUMMY */
   142 
   143 /* vi: set ts=4 sw=4 expandtab: */