If it helps, for CGBitmapContextCreate you just pass NULL ('nil' in
MacRuby) for the void *data parameter and let CoreGraphics handle
allocating memory. Unless you really need to do the allocation
yourself, it is significantly less painful and less error-prone to
have it done automatically, especially if you're using CoreGraphics
from MacRuby.Brian On Fri, Jan 9, 2009 at 12:00 AM, John Shea <[email protected]> wrote: > Thanks for the pointer ( ;-)) Dave, > I assume that there is some way to make it work since it seems, as you say, > to be catered for, but with my code it either gives back garbage (ie not a > pointer to the image i want) or falls into the debugger depending on whether > i access it more than once. > Never mind, I have a work-around that works fine - it was easy to call out > to an Objective C method where I could create the pointer in the C way (void > *data = malloc(width * height * 4);). > Cheers, > John > > > On Thu, Jan 8, 2009 at 6:45 PM, Dave Lee <[email protected]> wrote: >> >> try "^v". ^ is pointer, v is void. >> >> If you look at the .bridgesupport file, in this case >> >> /System/Library/Frameworks/ApplicationServices.framework/Frameworks/CoreGraphics.framework/Resources/BridgeSupport/CoreGraphicsFull.bridgesupport, >> you'll see the the objc types listed for the various functions, >> structs, etc. >> >> Dave >> >> On Sat, Jan 3, 2009 at 12:28 AM, John Shea <[email protected]> wrote: >> > So kind of on this topic .. >> > which one of these ("c", "i", "s" etc) do I use for void pointers (to >> > memory) eg. the data parameter in the method below? (when otherwise >> > appropriately changed to ruby and Application.services imported etc). >> > >> > CGContextRef CGBitmapContextCreate ( >> > void *data, >> > size_t width, >> > size_t height, >> > size_t bitsPerComponent, >> > size_t bytesPerRow, >> > CGColorSpaceRef colorspace, >> > CGBitmapInfo bitmapInfo >> > ); >> > >> > Cheers, >> > >> > J >> > >> > On Jan 2, 2009, at 11:21 PM, Dave Lee wrote: >> > >> > On Thu, Jan 1, 2009 at 7:37 PM, Lachie <[email protected]> wrote: >> > >> > Cheque it: >> > >> > http://developer.apple.com/DOCUMENTATION/Cocoa/Conceptual/ObjCRuntimeGuide/Articles/chapter_7_section_1.html#//apple_ref/doc/uid/TP40008048-CH100-SW1 >> > >> > see also: /usr/include/objc/runtime.h >> > >> > Dave >> > _______________________________________________ >> > MacRuby-devel mailing list >> > [email protected] >> > http://lists.macosforge.org/mailman/listinfo.cgi/macruby-devel >> > >> > >> > _______________________________________________ >> > MacRuby-devel mailing list >> > [email protected] >> > http://lists.macosforge.org/mailman/listinfo.cgi/macruby-devel >> > >> > >> _______________________________________________ >> MacRuby-devel mailing list >> [email protected] >> http://lists.macosforge.org/mailman/listinfo.cgi/macruby-devel > > > _______________________________________________ > MacRuby-devel mailing list > [email protected] > http://lists.macosforge.org/mailman/listinfo.cgi/macruby-devel > > _______________________________________________ MacRuby-devel mailing list [email protected] http://lists.macosforge.org/mailman/listinfo.cgi/macruby-devel
