SDL_nullvideo.c revision 46be48730333120a7b939116cef075e61c12c703
1/* 2 SDL - Simple DirectMedia Layer 3 Copyright (C) 1997-2006 Sam Lantinga 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 This library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with this library; if not, write to the Free Software 17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 19 Sam Lantinga 20 slouken@libsdl.org 21*/ 22#include "SDL_config.h" 23 24/* Dummy SDL video driver implementation; this is just enough to make an 25 * SDL-based application THINK it's got a working video driver, for 26 * applications that call SDL_Init(SDL_INIT_VIDEO) when they don't need it, 27 * and also for use as a collection of stubs when porting SDL to a new 28 * platform for which you haven't yet written a valid video driver. 29 * 30 * This is also a great way to determine bottlenecks: if you think that SDL 31 * is a performance problem for a given platform, enable this driver, and 32 * then see if your application runs faster without video overhead. 33 * 34 * Initial work by Ryan C. Gordon (icculus@icculus.org). A good portion 35 * of this was cut-and-pasted from Stephane Peter's work in the AAlib 36 * SDL video driver. Renamed to "DUMMY" by Sam Lantinga. 37 */ 38 39#include "SDL_video.h" 40#include "SDL_mouse.h" 41#include "../SDL_sysvideo.h" 42#include "../SDL_pixels_c.h" 43#include "../../events/SDL_events_c.h" 44 45#include "SDL_nullvideo.h" 46#include "SDL_nullevents_c.h" 47#include "SDL_nullmouse_c.h" 48 49#define DUMMYVID_DRIVER_NAME "dummy" 50 51/* Initialization/Query functions */ 52static int DUMMY_VideoInit(_THIS, SDL_PixelFormat *vformat); 53static SDL_Rect **DUMMY_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags); 54static SDL_Surface *DUMMY_SetVideoMode(_THIS, SDL_Surface *current, int width, int height, int bpp, Uint32 flags); 55static int DUMMY_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors); 56static void DUMMY_VideoQuit(_THIS); 57 58/* Hardware surface functions */ 59static int DUMMY_AllocHWSurface(_THIS, SDL_Surface *surface); 60static int DUMMY_LockHWSurface(_THIS, SDL_Surface *surface); 61static void DUMMY_UnlockHWSurface(_THIS, SDL_Surface *surface); 62static void DUMMY_FreeHWSurface(_THIS, SDL_Surface *surface); 63 64/* etc. */ 65static void DUMMY_UpdateRects(_THIS, int numrects, SDL_Rect *rects); 66 67/* DUMMY driver bootstrap functions */ 68 69static int DUMMY_Available(void) 70{ 71 const char *envr = SDL_getenv("SDL_VIDEODRIVER"); 72 if ((envr) && (SDL_strcmp(envr, DUMMYVID_DRIVER_NAME) == 0)) { 73 return(1); 74 } 75 76 return(0); 77} 78 79static void DUMMY_DeleteDevice(SDL_VideoDevice *device) 80{ 81 SDL_free(device->hidden); 82 SDL_free(device); 83} 84 85static SDL_VideoDevice *DUMMY_CreateDevice(int devindex) 86{ 87 SDL_VideoDevice *device; 88 89 /* Initialize all variables that we clean on shutdown */ 90 device = (SDL_VideoDevice *)SDL_malloc(sizeof(SDL_VideoDevice)); 91 if ( device ) { 92 SDL_memset(device, 0, (sizeof *device)); 93 device->hidden = (struct SDL_PrivateVideoData *) 94 SDL_malloc((sizeof *device->hidden)); 95 } 96 if ( (device == NULL) || (device->hidden == NULL) ) { 97 SDL_OutOfMemory(); 98 if ( device ) { 99 SDL_free(device); 100 } 101 return(0); 102 } 103 SDL_memset(device->hidden, 0, (sizeof *device->hidden)); 104 105 /* Set the function pointers */ 106 device->VideoInit = DUMMY_VideoInit; 107 device->ListModes = DUMMY_ListModes; 108 device->SetVideoMode = DUMMY_SetVideoMode; 109 device->CreateYUVOverlay = NULL; 110 device->SetColors = DUMMY_SetColors; 111 device->UpdateRects = DUMMY_UpdateRects; 112 device->VideoQuit = DUMMY_VideoQuit; 113 device->AllocHWSurface = DUMMY_AllocHWSurface; 114 device->CheckHWBlit = NULL; 115 device->FillHWRect = NULL; 116 device->SetHWColorKey = NULL; 117 device->SetHWAlpha = NULL; 118 device->LockHWSurface = DUMMY_LockHWSurface; 119 device->UnlockHWSurface = DUMMY_UnlockHWSurface; 120 device->FlipHWSurface = NULL; 121 device->FreeHWSurface = DUMMY_FreeHWSurface; 122 device->SetCaption = NULL; 123 device->SetIcon = NULL; 124 device->IconifyWindow = NULL; 125 device->GrabInput = NULL; 126 device->GetWMInfo = NULL; 127 device->InitOSKeymap = DUMMY_InitOSKeymap; 128 device->PumpEvents = DUMMY_PumpEvents; 129 130 device->free = DUMMY_DeleteDevice; 131 132 return device; 133} 134 135VideoBootStrap DUMMY_bootstrap = { 136 DUMMYVID_DRIVER_NAME, "SDL dummy video driver", 137 DUMMY_Available, DUMMY_CreateDevice 138}; 139 140 141int DUMMY_VideoInit(_THIS, SDL_PixelFormat *vformat) 142{ 143 /* 144 fprintf(stderr, "WARNING: You are using the SDL dummy video driver!\n"); 145 */ 146 147 /* Determine the screen depth (use default 8-bit depth) */ 148 /* we change this during the SDL_SetVideoMode implementation... */ 149 vformat->BitsPerPixel = 8; 150 vformat->BytesPerPixel = 1; 151 152 /* We're done! */ 153 return(0); 154} 155 156SDL_Rect **DUMMY_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags) 157{ 158 return (SDL_Rect **) -1; 159} 160 161SDL_Surface *DUMMY_SetVideoMode(_THIS, SDL_Surface *current, 162 int width, int height, int bpp, Uint32 flags) 163{ 164 if ( this->hidden->buffer ) { 165 SDL_free( this->hidden->buffer ); 166 } 167 168 this->hidden->buffer = SDL_malloc(width * height * (bpp / 8)); 169 if ( ! this->hidden->buffer ) { 170 SDL_SetError("Couldn't allocate buffer for requested mode"); 171 return(NULL); 172 } 173 174/* printf("Setting mode %dx%d\n", width, height); */ 175 176 SDL_memset(this->hidden->buffer, 0, width * height * (bpp / 8)); 177 178 /* Allocate the new pixel format for the screen */ 179 if ( ! SDL_ReallocFormat(current, bpp, 0, 0, 0, 0) ) { 180 SDL_free(this->hidden->buffer); 181 this->hidden->buffer = NULL; 182 SDL_SetError("Couldn't allocate new pixel format for requested mode"); 183 return(NULL); 184 } 185 186 /* Set up the new mode framebuffer */ 187 current->flags = flags & SDL_FULLSCREEN; 188 this->hidden->w = current->w = width; 189 this->hidden->h = current->h = height; 190 current->pitch = current->w * (bpp / 8); 191 current->pixels = this->hidden->buffer; 192 193 /* We're done */ 194 return(current); 195} 196 197/* We don't actually allow hardware surfaces other than the main one */ 198static int DUMMY_AllocHWSurface(_THIS, SDL_Surface *surface) 199{ 200 return(-1); 201} 202static void DUMMY_FreeHWSurface(_THIS, SDL_Surface *surface) 203{ 204 return; 205} 206 207/* We need to wait for vertical retrace on page flipped displays */ 208static int DUMMY_LockHWSurface(_THIS, SDL_Surface *surface) 209{ 210 return(0); 211} 212 213static void DUMMY_UnlockHWSurface(_THIS, SDL_Surface *surface) 214{ 215 return; 216} 217 218static void DUMMY_UpdateRects(_THIS, int numrects, SDL_Rect *rects) 219{ 220 /* do nothing. */ 221} 222 223int DUMMY_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors) 224{ 225 /* do nothing of note. */ 226 return(1); 227} 228 229/* Note: If we are terminated, this could be called in the middle of 230 another SDL video routine -- notably UpdateRects. 231*/ 232void DUMMY_VideoQuit(_THIS) 233{ 234 if (this->screen->pixels != NULL) 235 { 236 SDL_free(this->screen->pixels); 237 this->screen->pixels = NULL; 238 } 239} 240