src/fl_read_image_mac.cxx

   1 //
   2 // "$Id: fl_read_image_mac.cxx 8362 2011-02-02 18:39:34Z manolo $"
   3 //
   4 // WIN32 image reading routines for the Fast Light Tool Kit (FLTK).
   5 //
   6 // Copyright 1998-2010 by Bill Spitzak and others.
   7 //
   8 // This library is free software; you can redistribute it and/or
   9 // modify it under the terms of the GNU Library General Public
  10 // License as published by the Free Software Foundation; either
  11 // version 2 of the License, or (at your option) any later version.
  12 //
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 // Library General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU Library General Public
  19 // License along with this library; if not, write to the Free Software
  20 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21 // USA.
  22 //
  23 // Please report all bugs and problems on the following page:
  24 //
  25 //     http://www.fltk.org/str.php
  26 //
  27
  28 #include <config.h>
  29
  30 //
  31 // 'fl_read_image()' - Read an image from the current window or off-screen buffer.
  32 //
  33
  34 uchar *                         // O - Pixel buffer or NULL if failed
  35 fl_read_image(uchar *p,         // I - Pixel buffer or NULL to allocate
  36               int   x,          // I - Left position
  37               int   y,          // I - Top position
  38               int   w,          // I - Width of area to read
  39               int   h,          // I - Height of area to read
  40               int   alpha) {    // I - Alpha value for image (0 for none)
  41   uchar *base;
  42   int rowBytes, delta;
  43   if(fl_window == NULL) { // reading from an offscreen buffer
  44     CGContextRef src = (CGContextRef)fl_gc;   // get bitmap context
  45     base = (uchar *)CGBitmapContextGetData(src);  // get data
  46     if(!base) return NULL;
  47     int sw = CGBitmapContextGetWidth(src);
  48     int sh = CGBitmapContextGetHeight(src);
  49     rowBytes = CGBitmapContextGetBytesPerRow(src);
  50     delta = CGBitmapContextGetBitsPerPixel(src)/8;
  51     if( (sw - x < w) || (sh - y < h) )  return NULL;
  52     }
  53   else { // reading from current window
  54     Fl_Window *window = Fl_Window::current();
  55     while(window->window()) window = window->window();
  56     base = Fl_X::bitmap_from_window_rect(window,x,y,w,h,&delta);
  57     rowBytes = delta*w;
  58     x = y = 0;
  59     }
  60   // Allocate the image data array as needed...
  61   int d = alpha ? 4 : 3;
  62   if (!p) p = new uchar[w * h * d];
  63   // Initialize the default colors/alpha in the whole image...
  64   memset(p, alpha, w * h * d);
  65   // Copy the image from the off-screen buffer to the memory buffer.
  66   int           idx, idy;       // Current X & Y in image
  67   uchar *pdst, *psrc;
  68   for (idy = y, pdst = p; idy < h + y; idy ++) {
  69     for (idx = 0, psrc = base + idy * rowBytes + x * delta; idx < w; idx ++, psrc += delta, pdst += d) {
  70       pdst[0] = psrc[0];  // R
  71       pdst[1] = psrc[1];  // G
  72       pdst[2] = psrc[2];  // B
  73     }
  74   }
  75   if(fl_window != NULL) delete[] base;
  76   return p;
  77 }
  78
  79
  80 //
  81 // End of "$Id: fl_read_image_mac.cxx 8362 2011-02-02 18:39:34Z manolo $".
  82 //