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1 /*
2 IMPORTANT: This Apple software is supplied to you by Apple Computer, Inc. ("Apple") in
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5 please do not use, install or modify this Apple software.
6
7 In consideration of your agreement to abide by the following terms, and subject to these
8 terms, Apple grants you a personal, non-exclusive license, under Apple\xd5s copyrights in
9 this original Apple software (the "Apple Software"), to use and modify the Apple Software,
10 with or without modifications, in source and/or binary forms; provided that if you redistribute
11 the Apple Software in its entirety and without modifications, you must retain this notice and
12 the following text and disclaimers in all such redistributions of the Apple Software.
13 Neither the name, trademarks, service marks or logos of Apple Computer, Inc. may be used
14 to endorse or promote products derived from the Apple Software without specific prior
15 written permission from Apple. Except as expressly tated in this notice, no other rights or
16 licenses, express or implied, are granted by Apple herein, including but not limited
17 to any patent rights that may be infringed by your derivative works or by other works
18 in which the Apple Software may be incorporated.
19
20 The Apple Software is provided by Apple on an "AS IS" basis. APPLE MAKES NO WARRANTIES,
21 EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT,
22 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS
23 USE AND OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.
24
25 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL
26 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27 OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE,
28 REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND
29 WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR
30 OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include "wx/wxprec.h"
34
35 #if wxOSX_USE_COCOA_OR_CARBON
36
37 #import <CoreFoundation/CoreFoundation.h>
38 #import <ApplicationServices/ApplicationServices.h>
39 #import <OpenGL/OpenGL.h>
40 #import <OpenGL/gl.h>
41
42 #include "wx/osx/core/private.h"
43 #include "wx/osx/private/glgrab.h"
44
45 extern CGColorSpaceRef wxMacGetGenericRGBColorSpace();
46
47 /*
48 * perform an in-place swap from Quadrant 1 to Quadrant III format
49 * (upside-down PostScript/GL to right side up QD/CG raster format)
50 * We do this in-place, which requires more copying, but will touch
51 * only half the pages. (Display grabs are BIG!)
52 *
53 * Pixel reformatting may optionally be done here if needed.
54 */
55 static void swizzleBitmap(void * data, int rowBytes, int height)
56 {
57 int top, bottom;
58 void * buffer;
59 void * topP;
60 void * bottomP;
61 void * base;
62
63
64 top = 0;
65 bottom = height - 1;
66 base = data;
67 buffer = malloc(rowBytes);
68
69
70 while ( top < bottom )
71 {
72 topP = (void *)((top * rowBytes) + (intptr_t)base);
73 bottomP = (void *)((bottom * rowBytes) + (intptr_t)base);
74
75
76 /*
77 * Save and swap scanlines.
78 *
79 * This code does a simple in-place exchange with a temp buffer.
80 * If you need to reformat the pixels, replace the first two bcopy()
81 * calls with your own custom pixel reformatter.
82 */
83 bcopy( topP, buffer, rowBytes );
84 bcopy( bottomP, topP, rowBytes );
85 bcopy( buffer, bottomP, rowBytes );
86
87 ++top;
88 --bottom;
89 }
90 free( buffer );
91 }
92
93
94 /*
95 * Given a display ID and a rectangle on that display, generate a CGImageRef
96 * containing the display contents.
97 *
98 * srcRect is display-origin relative.
99 *
100 * This function uses a full screen OpenGL read-only context.
101 * By using OpenGL, we can read the screen using a DMA transfer
102 * when it's in millions of colors mode, and we can correctly read
103 * a microtiled full screen OpenGL context, such as a game or full
104 * screen video display.
105 *
106 * Returns a CGImageRef. When you are done with the CGImageRef, release it
107 * using CFRelease().
108 * Returns NULL on an error.
109 */
110
111 CGImageRef grabViaOpenGL(CGDirectDisplayID display, CGRect srcRect)
112 {
113 CGContextRef bitmap;
114 CGImageRef image;
115 void * data;
116 long bytewidth;
117 GLint width, height;
118 long bytes;
119
120 CGLContextObj glContextObj;
121 CGLPixelFormatObj pixelFormatObj ;
122 GLint numPixelFormats ;
123 CGLPixelFormatAttribute attribs[] =
124 {
125 kCGLPFAFullScreen,
126 kCGLPFADisplayMask,
127 (CGLPixelFormatAttribute) 0, /* Display mask bit goes here */
128 (CGLPixelFormatAttribute) 0
129 } ;
130
131
132 if ( display == kCGNullDirectDisplay )
133 display = CGMainDisplayID();
134 attribs[2] = (CGLPixelFormatAttribute) CGDisplayIDToOpenGLDisplayMask(display);
135
136
137 /* Build a full-screen GL context */
138 CGLChoosePixelFormat( attribs, &pixelFormatObj, &numPixelFormats );
139 if ( pixelFormatObj == NULL ) // No full screen context support
140 return NULL;
141 CGLCreateContext( pixelFormatObj, NULL, &glContextObj ) ;
142 CGLDestroyPixelFormat( pixelFormatObj ) ;
143 if ( glContextObj == NULL )
144 return NULL;
145
146
147 CGLSetCurrentContext( glContextObj ) ;
148 CGLSetFullScreen( glContextObj ) ;
149
150
151 glReadBuffer(GL_FRONT);
152
153
154 width = (GLint)srcRect.size.width;
155 height = (GLint)srcRect.size.height;
156
157
158 bytewidth = width * 4; // Assume 4 bytes/pixel for now
159 bytewidth = (bytewidth + 3) & ~3; // Align to 4 bytes
160 bytes = bytewidth * height; // width * height
161
162 /* Build bitmap context */
163 data = malloc(height * bytewidth);
164 if ( data == NULL )
165 {
166 CGLSetCurrentContext( NULL );
167 CGLClearDrawable( glContextObj ); // disassociate from full screen
168 CGLDestroyContext( glContextObj ); // and destroy the context
169 return NULL;
170 }
171 bitmap = CGBitmapContextCreate(data, width, height, 8, bytewidth,
172 wxMacGetGenericRGBColorSpace(), kCGImageAlphaNoneSkipFirst /* XRGB */);
173
174
175 /* Read framebuffer into our bitmap */
176 glFinish(); /* Finish all OpenGL commands */
177 glPixelStorei(GL_PACK_ALIGNMENT, 4); /* Force 4-byte alignment */
178 glPixelStorei(GL_PACK_ROW_LENGTH, 0);
179 glPixelStorei(GL_PACK_SKIP_ROWS, 0);
180 glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
181
182 /*
183 * Fetch the data in XRGB format, matching the bitmap context.
184 */
185 glReadPixels((GLint)srcRect.origin.x, (GLint)srcRect.origin.y, width, height,
186 GL_BGRA,
187 #ifdef __BIG_ENDIAN__
188 GL_UNSIGNED_INT_8_8_8_8_REV, // for PPC
189 #else
190 GL_UNSIGNED_INT_8_8_8_8, // for Intel! http://lists.apple.com/archives/quartz-dev/2006/May/msg00100.html
191 #endif
192 data);
193 /*
194 * glReadPixels generates a quadrant I raster, with origin in the lower left
195 * This isn't a problem for signal processing routines such as compressors,
196 * as they can simply use a negative 'advance' to move between scanlines.
197 * CGImageRef and CGBitmapContext assume a quadrant III raster, though, so we need to
198 * invert it. Pixel reformatting can also be done here.
199 */
200 swizzleBitmap(data, bytewidth, height);
201
202
203 /* Make an image out of our bitmap; does a cheap vm_copy of the bitmap */
204 image = CGBitmapContextCreateImage(bitmap);
205
206 /* Get rid of bitmap */
207 CFRelease(bitmap);
208 free(data);
209
210
211 /* Get rid of GL context */
212 CGLSetCurrentContext( NULL );
213 CGLClearDrawable( glContextObj ); // disassociate from full screen
214 CGLDestroyContext( glContextObj ); // and destroy the context
215
216 /* Returned image has a reference count of 1 */
217 return image;
218 }
219
220 #endif