/*

SDL - Simple DirectMedia Layer

Copyright (C) 2010 Eli Gottlieb

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public

License as published by the Free Software Foundation; either

version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public

License along with this library; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Eli Gottlieb

eligottlieb@gmail.com

*/

#include "SDL.h"

#include "SDL_video.h"

#include "SDL_sysvideo.h"

#include "SDL_pixels.h"

#include "SDL_surface.h"

SDL_Window*

SDL_CreateShapedWindow(const char *title,unsigned int x,unsigned int y,unsigned int w,unsigned int h,Uint32 flags) {

SDL_Window *result = SDL_CreateWindow(title,x,y,w,h,SDL_WINDOW_BORDERLESS | flags & !SDL_WINDOW_FULLSCREEN & !SDL_WINDOW_SHOWN);

if(result != NULL) {

result->shaper = result->display->device->shape_driver.CreateShaper(result);

if(result->shaper != NULL) {

result->shaper->usershownflag = flags & SDL_WINDOW_SHOWN;

result->shaper->mode.mode = ShapeModeDefault;

result->shaper->mode.parameters.binarizationCutoff = 1;

result->shaper->hasshape = SDL_FALSE;

return result;

}

else {

SDL_DestroyWindow(result);

return NULL;

}

}

else

return NULL;

}

SDL_bool

SDL_IsShapedWindow(const SDL_Window *window) {

if(window == NULL)

return SDL_FALSE;

else

return (SDL_bool)(window->shaper != NULL);

}

void

SDL_CalculateShapeBitmap(SDL_WindowShapeMode mode,SDL_Surface *shape,Uint8* bitmap,Uint8 ppb) {

int x = 0;

int y = 0;

Uint8 r = 0,g = 0,b = 0,alpha = 0;

Uint8* pixel = NULL;

Uint32 bitmap_pixel,pixel_value = 0,mask_value = 0;

SDL_Color key;

if(SDL_MUSTLOCK(shape))

SDL_LockSurface(shape);

pixel = (Uint8*)shape->pixels;

for(y = 0;y<shape->h;y++) {

for(x=0;x<shape->w;x++) {

alpha = 0;

pixel_value = 0;

pixel = (Uint8 *)(shape->pixels) + (y*shape->pitch) + (x*shape->format->BytesPerPixel);

switch(shape->format->BytesPerPixel) {

case(1):

pixel_value = *(Uint8*)pixel;

break;

case(2):

pixel_value = *(Uint16*)pixel;

break;

case(3):

pixel_value = *(Uint32*)pixel & (~shape->format->Amask);

break;

case(4):

pixel_value = *(Uint32*)pixel;

break;

}

SDL_GetRGBA(pixel_value,shape->format,&r,&g,&b,&alpha);

bitmap_pixel = y*shape->w + x;

switch(mode.mode) {

case(ShapeModeDefault):

mask_value = (alpha >= 1 ? 1 : 0);

break;

case(ShapeModeBinarizeAlpha):

mask_value = (alpha >= mode.parameters.binarizationCutoff ? 1 : 0);

break;

case(ShapeModeReverseBinarizeAlpha):

mask_value = (alpha <= mode.parameters.binarizationCutoff ? 1 : 0);

break;

case(ShapeModeColorKey):

key = mode.parameters.colorKey;

mask_value = ((key.r != r && key.g != g && key.b != b) ? 1 : 0);

break;

}

bitmap[bitmap_pixel / ppb] |= mask_value << (7 - ((ppb - 1) - (bitmap_pixel % ppb)));

}

}

if(SDL_MUSTLOCK(shape))

SDL_UnlockSurface(shape);

}

SDL_ShapeTree*

RecursivelyCalculateShapeTree(SDL_WindowShapeMode mode,SDL_Surface* mask,SDL_bool invert,SDL_Rect dimensions) {

int x = 0,y = 0;

Uint8* pixel = NULL;

Uint32 pixel_value = 0;

Uint8 r = 0,g = 0,b = 0,a = 0;

SDL_bool pixel_transparent = SDL_FALSE;

int last_transparent = -1;

SDL_Color key;

SDL_ShapeTree* result = (SDL_ShapeTree*)SDL_malloc(sizeof(SDL_ShapeTree));

SDL_Rect next = {0,0,0,0};

for(y=dimensions.y;y<dimensions.h;y++)

for(x=dimensions.x;x<dimensions.w;x++) {

pixel_value = 0;

pixel = (Uint8 *)(mask->pixels) + (y*mask->pitch) + (x*mask->format->BytesPerPixel);

switch(mask->format->BytesPerPixel) {

case(1):

pixel_value = *(Uint8*)pixel;

break;

case(2):

pixel_value = *(Uint16*)pixel;

break;

case(3):

pixel_value = *(Uint32*)pixel & (~mask->format->Amask);

break;

case(4):

pixel_value = *(Uint32*)pixel;

break;

}

SDL_GetRGBA(pixel_value,mask->format,&r,&g,&b,&a);

switch(mode.mode) {

case(ShapeModeDefault):

pixel_transparent = (SDL_bool)(a >= 1 ? !invert : invert);

break;

case(ShapeModeBinarizeAlpha):

pixel_transparent = (SDL_bool)(a >= mode.parameters.binarizationCutoff ? !invert : invert);

break;

case(ShapeModeReverseBinarizeAlpha):

pixel_transparent = (SDL_bool)(a <= mode.parameters.binarizationCutoff ? !invert : invert);

break;

case(ShapeModeColorKey):

key = mode.parameters.colorKey;

pixel_transparent = (SDL_bool)((key.r == r && key.g == g && key.b == b) ? !invert : invert);

break;

}

if(last_transparent == -1) {

last_transparent = pixel_transparent;

break;

}

if(last_transparent != pixel_transparent) {

result->kind = QuadShape;

//These will stay the same.

next.w = dimensions.w / 2;

next.h = dimensions.h / 2;

//These will change from recursion to recursion.

next.x = dimensions.x;

next.y = dimensions.y;

result->data.children.upleft = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,invert,next);

next.x = dimensions.w / 2 + 1;

//Unneeded: next.y = dimensions.y;

result->data.children.upright = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,invert,next);

next.x = dimensions.x;

next.y = dimensions.h / 2 + 1;

result->data.children.downleft = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,invert,next);

next.x = dimensions.w / 2 + 1;

//Unneeded: next.y = dimensions.h / 2 + 1;

result->data.children.downright = (struct SDL_ShapeTree *)RecursivelyCalculateShapeTree(mode,mask,invert,next);

return result;

}

}

//If we never recursed, all the pixels in this quadrant have the same "value".

result->kind = (last_transparent == SDL_FALSE ? OpaqueShape : TransparentShape);

result->data.shape = dimensions;

return result;

}

SDL_ShapeTree*

SDL_CalculateShapeTree(SDL_WindowShapeMode mode,SDL_Surface* shape,SDL_bool invert) {

SDL_Rect dimensions = {0,0,shape->w,shape->h};

SDL_ShapeTree* result = NULL;

if(SDL_MUSTLOCK(shape))

SDL_LockSurface(shape);

result = RecursivelyCalculateShapeTree(mode,shape,invert,dimensions);

if(SDL_MUSTLOCK(shape))

SDL_UnlockSurface(shape);

return result;

}

void

SDL_TraverseShapeTree(SDL_ShapeTree *tree,void(*function)(SDL_ShapeTree*,void*),void* closure) {

if(tree->kind == QuadShape) {

SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.upleft,function,closure);

SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.upright,function,closure);

SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.downleft,function,closure);

SDL_TraverseShapeTree((SDL_ShapeTree *)tree->data.children.downright,function,closure);

}

else

function(tree,closure);

}

void

SDL_FreeShapeTree(SDL_ShapeTree** shapeTree) {

if((*shapeTree)->kind == QuadShape) {

SDL_FreeShapeTree((SDL_ShapeTree **)&(*shapeTree)->data.children.upleft);

SDL_FreeShapeTree((SDL_ShapeTree **)&(*shapeTree)->data.children.upright);

SDL_FreeShapeTree((SDL_ShapeTree **)&(*shapeTree)->data.children.downleft);

SDL_FreeShapeTree((SDL_ShapeTree **)&(*shapeTree)->data.children.downright);

}

SDL_free(*shapeTree);

*shapeTree = NULL;

}

int

SDL_SetWindowShape(SDL_Window *window,SDL_Surface *shape,SDL_WindowShapeMode *shapeMode) {

int result;

if(window == NULL || !SDL_IsShapedWindow(window))

//The window given was not a shapeable window.

return SDL_NONSHAPEABLE_WINDOW;

if(shape == NULL)

//Invalid shape argument.

return SDL_INVALID_SHAPE_ARGUMENT;

if(shapeMode != NULL)

window->shaper->mode = *shapeMode;

//TODO: Platform-specific implementations of SetWindowShape. X11 is finished. Win32 is finished. Debugging is in progress on both.

result = window->display->device->shape_driver.SetWindowShape(window->shaper,shape,shapeMode);

window->shaper->hasshape = SDL_TRUE;

if((window->shaper->usershownflag & SDL_WINDOW_SHOWN) == SDL_WINDOW_SHOWN) {

SDL_ShowWindow(window);

window->shaper->usershownflag &= !SDL_WINDOW_SHOWN;

}

return result;

}

SDL_bool

SDL_WindowHasAShape(SDL_Window *window) {

if (window == NULL && !SDL_IsShapedWindow(window))

return SDL_FALSE;

return window->shaper->hasshape;

}

int

SDL_GetShapedWindowMode(SDL_Window *window,SDL_WindowShapeMode *shapeMode) {

if(window != NULL && SDL_IsShapedWindow(window)) {

if(shapeMode == NULL) {

if(SDL_WindowHasAShape(window))

//The window given has a shape.

return 0;

else

//The window given is shapeable but lacks a shape.

return SDL_WINDOW_LACKS_SHAPE;

}

else {

*shapeMode = window->shaper->mode;

return 0;

}

}

else

//The window given is not a valid shapeable window.

return SDL_NONSHAPEABLE_WINDOW;