src/video/SDL_shape.c
author Sam Lantinga <slouken@libsdl.org>
Tue, 08 Feb 2011 16:50:51 -0800
changeset 5229 c015d3e63631
parent 4861 b67815cf9f25
child 5246 58265e606e4e
permissions -rw-r--r--
Fixed setting the texture unit, still doesn't work.
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 2010 Eli Gottlieb
     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     Eli Gottlieb
    20     eligottlieb@gmail.com
    21 */
    22 #include "SDL_config.h"
    23 
    24 #include "SDL.h"
    25 #include "SDL_assert.h"
    26 #include "SDL_video.h"
    27 #include "SDL_sysvideo.h"
    28 #include "SDL_pixels.h"
    29 #include "SDL_surface.h"
    30 #include "SDL_shape.h"
    31 #include "SDL_shape_internals.h"
    32 
    33 SDL_Window*
    34 SDL_CreateShapedWindow(const char *title,unsigned int x,unsigned int y,unsigned int w,unsigned int h,Uint32 flags) {
    35     SDL_Window *result = NULL;
    36     result = SDL_CreateWindow(title,-1000,-1000,w,h,(flags | SDL_WINDOW_BORDERLESS) & (~SDL_WINDOW_FULLSCREEN) & (~SDL_WINDOW_RESIZABLE) /*& (~SDL_WINDOW_SHOWN)*/);
    37     if(result != NULL) {
    38         result->shaper = result->display->device->shape_driver.CreateShaper(result);
    39         if(result->shaper != NULL) {
    40             result->shaper->userx = x;
    41             result->shaper->usery = y;
    42             result->shaper->mode.mode = ShapeModeDefault;
    43             result->shaper->mode.parameters.binarizationCutoff = 1;
    44             result->shaper->hasshape = SDL_FALSE;
    45             return result;
    46         }
    47         else {
    48             SDL_DestroyWindow(result);
    49             return NULL;
    50         }
    51     }
    52     else
    53         return NULL;
    54 }
    55 
    56 SDL_bool
    57 SDL_IsShapedWindow(const SDL_Window *window) {
    58     if(window == NULL)
    59         return SDL_FALSE;
    60     else
    61         return (SDL_bool)(window->shaper != NULL);
    62 }
    63 
    64 /* REQUIRES that bitmap point to a w-by-h bitmap with ppb pixels-per-byte. */
    65 void
    66 SDL_CalculateShapeBitmap(SDL_WindowShapeMode mode,SDL_Surface *shape,Uint8* bitmap,Uint8 ppb) {
    67     int x = 0;
    68     int y = 0;
    69     Uint8 r = 0,g = 0,b = 0,alpha = 0;
    70     Uint8* pixel = NULL;
    71     Uint32 bitmap_pixel,pixel_value = 0,mask_value = 0;
    72     SDL_Color key;
    73     if(SDL_MUSTLOCK(shape))
    74         SDL_LockSurface(shape);
    75     pixel = (Uint8*)shape->pixels;
    76     for(y = 0;y<shape->h;y++) {
    77         for(x=0;x<shape->w;x++) {
    78             alpha = 0;
    79             pixel_value = 0;
    80             pixel = (Uint8 *)(shape->pixels) + (y*shape->pitch) + (x*shape->format->BytesPerPixel);
    81             switch(shape->format->BytesPerPixel) {
    82                 case(1):
    83                     pixel_value = *(Uint8*)pixel;
    84                     break;
    85                 case(2):
    86                     pixel_value = *(Uint16*)pixel;
    87                     break;
    88                 case(3):
    89                     pixel_value = *(Uint32*)pixel & (~shape->format->Amask);
    90                     break;
    91                 case(4):
    92                     pixel_value = *(Uint32*)pixel;
    93                     break;
    94             }
    95             SDL_GetRGBA(pixel_value,shape->format,&r,&g,&b,&alpha);
    96             bitmap_pixel = y*shape->w + x;
    97             switch(mode.mode) {
    98                 case(ShapeModeDefault):
    99                     mask_value = (alpha >= 1 ? 1 : 0);
   100                     break;
   101                 case(ShapeModeBinarizeAlpha):
   102                     mask_value = (alpha >= mode.parameters.binarizationCutoff ? 1 : 0);
   103                     break;
   104                 case(ShapeModeReverseBinarizeAlpha):
   105                     mask_value = (alpha <= mode.parameters.binarizationCutoff ? 1 : 0);
   106                     break;
   107                 case(ShapeModeColorKey):
   108                     key = mode.parameters.colorKey;
   109                     mask_value = ((key.r != r || key.g != g || key.b != b) ? 1 : 0);
   110                     break;
   111             }
   112             bitmap[bitmap_pixel / ppb] |= mask_value << (7 - ((ppb - 1) - (bitmap_pixel % ppb)));
   113         }
   114     }
   115     if(SDL_MUSTLOCK(shape))
   116         SDL_UnlockSurface(shape);
   117 }
   118 
   119 SDL_ShapeTree*
   120 RecursivelyCalculateShapeTree(SDL_WindowShapeMode mode,SDL_Surface* mask,SDL_Rect dimensions) {
   121     int x = 0,y = 0;
   122     Uint8* pixel = NULL;
   123     Uint32 pixel_value = 0;
   124     Uint8 r = 0,g = 0,b = 0,a = 0;
   125     SDL_bool pixel_opaque = SDL_FALSE;
   126     int last_opaque = -1;
   127     SDL_Color key;
   128     SDL_ShapeTree* result = (SDL_ShapeTree*)SDL_malloc(sizeof(SDL_ShapeTree));
   129     SDL_Rect next = {0,0,0,0};
   130     for(y=dimensions.y;y<dimensions.y + dimensions.h;y++) {
   131         for(x=dimensions.x;x<dimensions.x + dimensions.w;x++) {
   132             pixel_value = 0;
   133             pixel = (Uint8 *)(mask->pixels) + (y*mask->pitch) + (x*mask->format->BytesPerPixel);
   134             switch(mask->format->BytesPerPixel) {
   135                 case(1):
   136                     pixel_value = *(Uint8*)pixel;
   137                     break;
   138                 case(2):
   139                     pixel_value = *(Uint16*)pixel;
   140                     break;
   141                 case(3):
   142                     pixel_value = *(Uint32*)pixel & (~mask->format->Amask);
   143                     break;
   144                 case(4):
   145                     pixel_value = *(Uint32*)pixel;
   146                     break;
   147             }
   148             SDL_GetRGBA(pixel_value,mask->format,&r,&g,&b,&a);
   149             switch(mode.mode) {
   150                 case(ShapeModeDefault):
   151                     pixel_opaque = (a >= 1 ? SDL_TRUE : SDL_FALSE);
   152                     break;
   153                 case(ShapeModeBinarizeAlpha):
   154                     pixel_opaque = (a >= mode.parameters.binarizationCutoff ? SDL_TRUE : SDL_FALSE);
   155                     break;
   156                 case(ShapeModeReverseBinarizeAlpha):
   157                     pixel_opaque = (a <= mode.parameters.binarizationCutoff ? SDL_TRUE : SDL_FALSE);
   158                     break;
   159                 case(ShapeModeColorKey):
   160                     key = mode.parameters.colorKey;
   161                     pixel_opaque = ((key.r != r || key.g != g || key.b != b) ? SDL_TRUE : SDL_FALSE);
   162                     break;
   163             }
   164             if(last_opaque == -1)
   165                 last_opaque = pixel_opaque;
   166             if(last_opaque != pixel_opaque) {
   167                 result->kind = QuadShape;
   168                 //These will stay the same.
   169                 next.w = dimensions.w / 2;
   170                 next.h = dimensions.h / 2;
   171                 //These will change from recursion to recursion.
   172                 next.x = dimensions.x;
   173                 next.y = dimensions.y;
   174                 result->data.children.upleft = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,next);
   175                 next.x += next.w;
   176                 //Unneeded: next.y = dimensions.y;
   177                 result->data.children.upright = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,next);
   178                 next.x = dimensions.x;
   179                 next.y += next.h;
   180                 result->data.children.downleft = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,next);
   181                 next.x += next.w;
   182                 //Unneeded: next.y = dimensions.y + dimensions.h /2;
   183                 result->data.children.downright = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,next);
   184                 return result;
   185             }
   186         }
   187     }
   188     //If we never recursed, all the pixels in this quadrant have the same "value".
   189     result->kind = (last_opaque == SDL_TRUE ? OpaqueShape : TransparentShape);
   190     result->data.shape = dimensions;
   191     return result;
   192 }
   193 
   194 SDL_ShapeTree*
   195 SDL_CalculateShapeTree(SDL_WindowShapeMode mode,SDL_Surface* shape) {
   196     SDL_Rect dimensions = {0,0,shape->w,shape->h};
   197     SDL_ShapeTree* result = NULL;
   198     if(SDL_MUSTLOCK(shape))
   199         SDL_LockSurface(shape);
   200     result = RecursivelyCalculateShapeTree(mode,shape,dimensions);
   201     if(SDL_MUSTLOCK(shape))
   202         SDL_UnlockSurface(shape);
   203     return result;
   204 }
   205 
   206 void
   207 SDL_TraverseShapeTree(SDL_ShapeTree *tree,SDL_TraversalFunction function,void* closure) {
   208     SDL_assert(tree != NULL);
   209     if(tree->kind == QuadShape) {
   210         SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.upleft,function,closure);
   211         SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.upright,function,closure);
   212         SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.downleft,function,closure);
   213         SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.downright,function,closure);
   214     }
   215     else
   216         function(tree,closure);
   217 }
   218 
   219 void
   220 SDL_FreeShapeTree(SDL_ShapeTree** shape_tree) {
   221     if((*shape_tree)->kind == QuadShape) {
   222         SDL_FreeShapeTree((SDL_ShapeTree **)&(*shape_tree)->data.children.upleft);
   223         SDL_FreeShapeTree((SDL_ShapeTree **)&(*shape_tree)->data.children.upright);
   224         SDL_FreeShapeTree((SDL_ShapeTree **)&(*shape_tree)->data.children.downleft);
   225         SDL_FreeShapeTree((SDL_ShapeTree **)&(*shape_tree)->data.children.downright);
   226     }
   227     SDL_free(*shape_tree);
   228     *shape_tree = NULL;
   229 }
   230 
   231 int
   232 SDL_SetWindowShape(SDL_Window *window,SDL_Surface *shape,SDL_WindowShapeMode *shape_mode) {
   233     int result;
   234     if(window == NULL || !SDL_IsShapedWindow(window))
   235         //The window given was not a shapeable window.
   236         return SDL_NONSHAPEABLE_WINDOW;
   237     if(shape == NULL)
   238         //Invalid shape argument.
   239         return SDL_INVALID_SHAPE_ARGUMENT;
   240     
   241     if(shape_mode != NULL)
   242         window->shaper->mode = *shape_mode;
   243     result = window->display->device->shape_driver.SetWindowShape(window->shaper,shape,shape_mode);
   244     window->shaper->hasshape = SDL_TRUE;
   245     if(window->shaper->userx != 0 && window->shaper->usery != 0) {
   246         SDL_SetWindowPosition(window,window->shaper->userx,window->shaper->usery);
   247         window->shaper->userx = 0;
   248         window->shaper->usery = 0;
   249     }
   250     return result;
   251 }
   252 
   253 SDL_bool
   254 SDL_WindowHasAShape(SDL_Window *window) {
   255     if (window == NULL || !SDL_IsShapedWindow(window))
   256         return SDL_FALSE;
   257     return window->shaper->hasshape;
   258 }
   259 
   260 int
   261 SDL_GetShapedWindowMode(SDL_Window *window,SDL_WindowShapeMode *shape_mode) {
   262     if(window != NULL && SDL_IsShapedWindow(window)) {
   263         if(shape_mode == NULL) {
   264             if(SDL_WindowHasAShape(window))
   265                 //The window given has a shape.
   266                 return 0;
   267             else
   268                 //The window given is shapeable but lacks a shape.
   269                 return SDL_WINDOW_LACKS_SHAPE;
   270         }
   271         else {
   272             *shape_mode = window->shaper->mode;
   273             return 0;
   274         }
   275     }
   276     else
   277         //The window given is not a valid shapeable window.
   278         return SDL_NONSHAPEABLE_WINDOW;
   279 }