]> git.saurik.com Git - wxWidgets.git/blame - src/osx/core/glgrab.cpp
fix memory leak in wxScreenDC, fixes #13249
[wxWidgets.git] / src / osx / core / glgrab.cpp
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1/*
2 IMPORTANT: This Apple software is supplied to you by Apple Computer, Inc. ("Apple") in
3 consideration of your agreement to the following terms, and your use, installation or modification
4 of this Apple software constitutes acceptance of these terms. If you do not agree with these terms,
5 please do not use, install or modify this Apple software.
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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.
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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.
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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
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33#include "wx/wxprec.h"
34
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35#if wxOSX_USE_COCOA_OR_CARBON
36
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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/private/glgrab.h"
43
44extern CGColorSpaceRef wxMacGetGenericRGBColorSpace();
45
46/*
47 * perform an in-place swap from Quadrant 1 to Quadrant III format
48 * (upside-down PostScript/GL to right side up QD/CG raster format)
49 * We do this in-place, which requires more copying, but will touch
50 * only half the pages. (Display grabs are BIG!)
51 *
52 * Pixel reformatting may optionally be done here if needed.
53 */
54static void swizzleBitmap(void * data, int rowBytes, int height)
55{
56 int top, bottom;
57 void * buffer;
58 void * topP;
59 void * bottomP;
60 void * base;
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61
62
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63 top = 0;
64 bottom = height - 1;
65 base = data;
66 buffer = malloc(rowBytes);
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67
68
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69 while ( top < bottom )
70 {
71 topP = (void *)((top * rowBytes) + (intptr_t)base);
72 bottomP = (void *)((bottom * rowBytes) + (intptr_t)base);
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73
74
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75 /*
76 * Save and swap scanlines.
77 *
78 * This code does a simple in-place exchange with a temp buffer.
79 * If you need to reformat the pixels, replace the first two bcopy()
80 * calls with your own custom pixel reformatter.
81 */
82 bcopy( topP, buffer, rowBytes );
83 bcopy( bottomP, topP, rowBytes );
84 bcopy( buffer, bottomP, rowBytes );
03647350 85
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86 ++top;
87 --bottom;
88 }
89 free( buffer );
90}
91
92
93/*
94 * Given a display ID and a rectangle on that display, generate a CGImageRef
95 * containing the display contents.
96 *
97 * srcRect is display-origin relative.
98 *
99 * This function uses a full screen OpenGL read-only context.
100 * By using OpenGL, we can read the screen using a DMA transfer
101 * when it's in millions of colors mode, and we can correctly read
102 * a microtiled full screen OpenGL context, such as a game or full
103 * screen video display.
104 *
105 * Returns a CGImageRef. When you are done with the CGImageRef, release it
106 * using CFRelease().
107 * Returns NULL on an error.
108 */
03647350 109
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110CGImageRef grabViaOpenGL(CGDirectDisplayID display, CGRect srcRect)
111{
112 CGContextRef bitmap;
113 CGImageRef image;
114 void * data;
115 long bytewidth;
116 GLint width, height;
117 long bytes;
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119 CGLContextObj glContextObj;
120 CGLPixelFormatObj pixelFormatObj ;
121 GLint numPixelFormats ;
122 CGLPixelFormatAttribute attribs[] =
123 {
124 kCGLPFAFullScreen,
125 kCGLPFADisplayMask,
126 (CGLPixelFormatAttribute) 0, /* Display mask bit goes here */
127 (CGLPixelFormatAttribute) 0
128 } ;
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129
130
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131 if ( display == kCGNullDirectDisplay )
132 display = CGMainDisplayID();
133 attribs[2] = (CGLPixelFormatAttribute) CGDisplayIDToOpenGLDisplayMask(display);
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134
135
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136 /* Build a full-screen GL context */
137 CGLChoosePixelFormat( attribs, &pixelFormatObj, &numPixelFormats );
138 if ( pixelFormatObj == NULL ) // No full screen context support
139 return NULL;
140 CGLCreateContext( pixelFormatObj, NULL, &glContextObj ) ;
141 CGLDestroyPixelFormat( pixelFormatObj ) ;
142 if ( glContextObj == NULL )
143 return NULL;
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144
145
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146 CGLSetCurrentContext( glContextObj ) ;
147 CGLSetFullScreen( glContextObj ) ;
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148
149
4fcb208a 150 glReadBuffer(GL_FRONT);
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151
152
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153 width = (GLint)srcRect.size.width;
154 height = (GLint)srcRect.size.height;
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155
156
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157 bytewidth = width * 4; // Assume 4 bytes/pixel for now
158 bytewidth = (bytewidth + 3) & ~3; // Align to 4 bytes
159 bytes = bytewidth * height; // width * height
03647350 160
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161 /* Build bitmap context */
162 data = malloc(height * bytewidth);
163 if ( data == NULL )
164 {
165 CGLSetCurrentContext( NULL );
166 CGLClearDrawable( glContextObj ); // disassociate from full screen
167 CGLDestroyContext( glContextObj ); // and destroy the context
168 return NULL;
169 }
170 bitmap = CGBitmapContextCreate(data, width, height, 8, bytewidth,
171 wxMacGetGenericRGBColorSpace(), kCGImageAlphaNoneSkipFirst /* XRGB */);
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172
173
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174 /* Read framebuffer into our bitmap */
175 glFinish(); /* Finish all OpenGL commands */
176 glPixelStorei(GL_PACK_ALIGNMENT, 4); /* Force 4-byte alignment */
177 glPixelStorei(GL_PACK_ROW_LENGTH, 0);
178 glPixelStorei(GL_PACK_SKIP_ROWS, 0);
179 glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
03647350 180
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181 /*
182 * Fetch the data in XRGB format, matching the bitmap context.
183 */
184 glReadPixels((GLint)srcRect.origin.x, (GLint)srcRect.origin.y, width, height,
185 GL_BGRA,
186#ifdef __BIG_ENDIAN__
187 GL_UNSIGNED_INT_8_8_8_8_REV, // for PPC
188#else
189 GL_UNSIGNED_INT_8_8_8_8, // for Intel! http://lists.apple.com/archives/quartz-dev/2006/May/msg00100.html
190#endif
191 data);
192 /*
193 * glReadPixels generates a quadrant I raster, with origin in the lower left
194 * This isn't a problem for signal processing routines such as compressors,
195 * as they can simply use a negative 'advance' to move between scanlines.
196 * CGImageRef and CGBitmapContext assume a quadrant III raster, though, so we need to
197 * invert it. Pixel reformatting can also be done here.
198 */
199 swizzleBitmap(data, bytewidth, height);
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200
201
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202 /* Make an image out of our bitmap; does a cheap vm_copy of the bitmap */
203 image = CGBitmapContextCreateImage(bitmap);
03647350 204
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205 /* Get rid of bitmap */
206 CFRelease(bitmap);
207 free(data);
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208
209
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210 /* Get rid of GL context */
211 CGLSetCurrentContext( NULL );
212 CGLClearDrawable( glContextObj ); // disassociate from full screen
213 CGLDestroyContext( glContextObj ); // and destroy the context
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215 /* Returned image has a reference count of 1 */
216 return image;
217}
218
afd5d91c 219#endif