src/video/x11/SDL_x11shape.c

   1 /*
   2   Simple DirectMedia Layer
   3   Copyright (C) 1997-2018 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_X11
  24
  25 #include "SDL_assert.h"
  26 #include "SDL_x11video.h"
  27 #include "SDL_x11shape.h"
  28 #include "SDL_x11window.h"
  29 #include "../SDL_shape_internals.h"
  30
  31 SDL_WindowShaper*
  32 X11_CreateShaper(SDL_Window* window) {
  33     SDL_WindowShaper* result = NULL;
  34     SDL_ShapeData* data = NULL;
  35     int resized_properly;
  36
  37 #if SDL_VIDEO_DRIVER_X11_XSHAPE
  38     if (SDL_X11_HAVE_XSHAPE) {  /* Make sure X server supports it. */
  39         result = malloc(sizeof(SDL_WindowShaper));
  40         result->window = window;
  41         result->mode.mode = ShapeModeDefault;
  42         result->mode.parameters.binarizationCutoff = 1;
  43         result->userx = result->usery = 0;
  44         data = SDL_malloc(sizeof(SDL_ShapeData));
  45         result->driverdata = data;
  46         data->bitmapsize = 0;
  47         data->bitmap = NULL;
  48         window->shaper = result;
  49         resized_properly = X11_ResizeWindowShape(window);
  50         SDL_assert(resized_properly == 0);
  51     }
  52 #endif
  53
  54     return result;
  55 }
  56
  57 int
  58 X11_ResizeWindowShape(SDL_Window* window) {
  59     SDL_ShapeData* data = window->shaper->driverdata;
  60     unsigned int bitmapsize = window->w / 8;
  61     SDL_assert(data != NULL);
  62
  63     if(window->w % 8 > 0)
  64         bitmapsize += 1;
  65     bitmapsize *= window->h;
  66     if(data->bitmapsize != bitmapsize || data->bitmap == NULL) {
  67         data->bitmapsize = bitmapsize;
  68         if(data->bitmap != NULL)
  69             free(data->bitmap);
  70         data->bitmap = malloc(data->bitmapsize);
  71         if(data->bitmap == NULL) {
  72             return SDL_SetError("Could not allocate memory for shaped-window bitmap.");
  73         }
  74     }
  75     memset(data->bitmap,0,data->bitmapsize);
  76
  77     window->shaper->userx = window->x;
  78     window->shaper->usery = window->y;
  79     SDL_SetWindowPosition(window,-1000,-1000);
  80
  81     return 0;
  82 }
  83
  84 int
  85 X11_SetWindowShape(SDL_WindowShaper *shaper,SDL_Surface *shape,SDL_WindowShapeMode *shape_mode) {
  86     SDL_ShapeData *data = NULL;
  87     SDL_WindowData *windowdata = NULL;
  88     Pixmap shapemask;
  89
  90     if(shaper == NULL || shape == NULL || shaper->driverdata == NULL)
  91         return -1;
  92
  93 #if SDL_VIDEO_DRIVER_X11_XSHAPE
  94     if(shape->format->Amask == 0 && SDL_SHAPEMODEALPHA(shape_mode->mode))
  95         return -2;
  96     if(shape->w != shaper->window->w || shape->h != shaper->window->h)
  97         return -3;
  98     data = shaper->driverdata;
  99
 100     /* Assume that shaper->alphacutoff already has a value, because SDL_SetWindowShape() should have given it one. */
 101     SDL_CalculateShapeBitmap(shaper->mode,shape,data->bitmap,8);
 102
 103     windowdata = (SDL_WindowData*)(shaper->window->driverdata);
 104     shapemask = X11_XCreateBitmapFromData(windowdata->videodata->display,windowdata->xwindow,data->bitmap,shaper->window->w,shaper->window->h);
 105
 106     X11_XShapeCombineMask(windowdata->videodata->display,windowdata->xwindow, ShapeBounding, 0, 0,shapemask, ShapeSet);
 107     X11_XSync(windowdata->videodata->display,False);
 108
 109     X11_XFreePixmap(windowdata->videodata->display,shapemask);
 110 #endif
 111
 112     return 0;
 113 }
 114
 115 #endif /* SDL_VIDEO_DRIVER_X11 */