iphone Programming Glossary: pointer

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

byteCount size_t pixelCount CGContextRef context CGColorSpaceRef colorSpace UInt8 pixelByteData A pointer to an array of RGBA bytes in memory RPVW_RGBAPixel pixelData The pixel struct with alpha in this version.. 0 0 self.size.width self.size.height CGContextDrawImage context rect self.CGImage Now we can get a pointer to the image pixelData associated with the bitmap context. pixelData RGBAPixel CGBitmapContextGetData.. holding raw pixel data copied from Quartz CGImage held in receiver self UInt8 pixelByteData A pointer to the first pixel element in an array RGBPixel pixelData Step 4. Subclass code I put in a method named..

OpenGL ES iPhone - drawing anti aliased lines

http://stackoverflow.com/questions/1813035/opengl-es-iphone-drawing-anti-aliased-lines

en us um people hoppe overdraw.pdf You could do something along this way Colors is a pointer to unsigned bytes 4 per color . Should alternate in opacity. glColorPointer 4 GL_UNSIGNED_BYTE 0 colors.. opacity. glColorPointer 4 GL_UNSIGNED_BYTE 0 colors glEnableClientState GL_COLOR_ARRAY points is a pointer to floats 2 per vertex glVertexPointer 2 GL_FLOAT 0 points glEnableClientState GL_VERTEX_ARRAY glDrawArrays..

Fast and Lean PDF Viewer for iPhone / iPad / iOs - tips and hints?

http://stackoverflow.com/questions/3889634/fast-and-lean-pdf-viewer-for-iphone-ipad-ios-tips-and-hints

if they will be using memory beware of leaving contexts open though Recycle page objects by doing pointer swaps or destroy unused views Close any open Contexts as soon as you don't need them on receiving memory..

performSelector may cause a leak because its selector is unknown

http://stackoverflow.com/questions/7017281/performselector-may-cause-a-leak-because-its-selector-is-unknown

selector Explanation What's going on here is you're asking the controller for the C function pointer for the method corresponding to the controller. All objects respond to methodForSelector and it works.. C runtime methods so you could do this directly with the runtime API as well . These function pointers are called IMP s and are simple typedef ed function pointers id IMP id SEL ... 1 . This may be close.. runtime API as well . These function pointers are called IMP s and are simple typedef ed function pointers id IMP id SEL ... 1 . This may be close to the actual method signature of the method but will not always..

How to convert NSData to byte array in iPhone?

http://stackoverflow.com/questions/724086/how-to-convert-nsdata-to-byte-array-in-iphone

an array using a variable so Byte byteData len won't work. If you want to copy the data from a pointer you also need to memcpy which will go through the data pointed to by the pointer and copy each byte.. the data from a pointer you also need to memcpy which will go through the data pointed to by the pointer and copy each byte up to a specified length . Try NSData data NSData dataWithContentsOfFile filePath..

To ARC or not to ARC? What are the pros and cons?

http://stackoverflow.com/questions/8760431/to-arc-or-not-to-arc-what-are-the-pros-and-cons

Fancy handling of ObjC varargs can also cause trouble. Most things involving math on an ObjC pointer is trickier. You shouldn't have much of this in any case. You cannot put an id in a struct . This is.. iPhoneOS 3 or Mac OS X 10.5 or earlier. This precludes me from using ARC in many projects. __weak pointers do not work correctly on iOS 4 or Mac OS X 10.6 which is a shame but fairly easy to work around. __weak.. work correctly on iOS 4 or Mac OS X 10.6 which is a shame but fairly easy to work around. __weak pointers are great but they're not the #1 selling point of ARC. For 95 of code out there ARC is brilliant and..

Objective-C ARC: strong vs retain and weak vs assign

http://stackoverflow.com/questions/8927727/objective-c-arc-strong-vs-retain-and-weak-vs-assign

weak vs assign From my understanding the only difference here is that weak will assign nil to the pointer while assign won't which means the program will crash when I send a message to the pointer once it's.. to the pointer while assign won't which means the program will crash when I send a message to the pointer once it's been released. But if I use weak this won't ever happen because message send to nil won't..

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

I declared instance variables size_t bytesPerRow size_t byteCount size_t pixelCount CGContextRef context CGColorSpaceRef colorSpace UInt8 pixelByteData A pointer to an array of RGBA bytes in memory RPVW_RGBAPixel pixelData The pixel struct with alpha in this version typedef struct RGBAPixel byte red byte green byte blue.. image pixelData in the specified color space. CGRect rect 0 0 self.size.width self.size.height CGContextDrawImage context rect self.CGImage Now we can get a pointer to the image pixelData associated with the bitmap context. pixelData RGBAPixel CGBitmapContextGetData context return pixelData Read Only Data Previous information.. to Quartz CGImage for receiver self CFDataRef bitmapData Buffer holding raw pixel data copied from Quartz CGImage held in receiver self UInt8 pixelByteData A pointer to the first pixel element in an array RGBPixel pixelData Step 4. Subclass code I put in a method named bitmap to return the bitmap pixel data Get the bitmap data..

OpenGL ES iPhone - drawing anti aliased lines

http://stackoverflow.com/questions/1813035/opengl-es-iphone-drawing-anti-aliased-lines

with AA You can read a paper about this here http research.microsoft.com en us um people hoppe overdraw.pdf You could do something along this way Colors is a pointer to unsigned bytes 4 per color . Should alternate in opacity. glColorPointer 4 GL_UNSIGNED_BYTE 0 colors glEnableClientState GL_COLOR_ARRAY points is a pointer to.. pointer to unsigned bytes 4 per color . Should alternate in opacity. glColorPointer 4 GL_UNSIGNED_BYTE 0 colors glEnableClientState GL_COLOR_ARRAY points is a pointer to floats 2 per vertex glVertexPointer 2 GL_FLOAT 0 points glEnableClientState GL_VERTEX_ARRAY glDrawArrays GL_TRIANGLE_STRIP 0 points_count glDisableClientState..

Fast and Lean PDF Viewer for iPhone / iPad / iOs - tips and hints?

http://stackoverflow.com/questions/3889634/fast-and-lean-pdf-viewer-for-iphone-ipad-ios-tips-and-hints

Cancel needless NSOperations When you can especially if they will be using memory beware of leaving contexts open though Recycle page objects by doing pointer swaps or destroy unused views Close any open Contexts as soon as you don't need them on receiving memory warnings release and reload the DocRef and any page Caches..

performSelector may cause a leak because its selector is unknown

http://stackoverflow.com/questions/7017281/performselector-may-cause-a-leak-because-its-selector-is-unknown

void id SEL _controller methodForSelector selector _controller selector Explanation What's going on here is you're asking the controller for the C function pointer for the method corresponding to the controller. All objects respond to methodForSelector and it works through some lower level Objective C runtime methods so you.. and it works through some lower level Objective C runtime methods so you could do this directly with the runtime API as well . These function pointers are called IMP s and are simple typedef ed function pointers id IMP id SEL ... 1 . This may be close to the actual method signature of the method but will not.. C runtime methods so you could do this directly with the runtime API as well . These function pointers are called IMP s and are simple typedef ed function pointers id IMP id SEL ... 1 . This may be close to the actual method signature of the method but will not always match exactly. Once you have the IMP you need to cast..

How to convert NSData to byte array in iPhone?

http://stackoverflow.com/questions/724086/how-to-convert-nsdata-to-byte-array-in-iphone

conversion share improve this question You can't declare an array using a variable so Byte byteData len won't work. If you want to copy the data from a pointer you also need to memcpy which will go through the data pointed to by the pointer and copy each byte up to a specified length . Try NSData data NSData dataWithContentsOfFile.. variable so Byte byteData len won't work. If you want to copy the data from a pointer you also need to memcpy which will go through the data pointed to by the pointer and copy each byte up to a specified length . Try NSData data NSData dataWithContentsOfFile filePath NSUInteger len data length Byte byteData Byte malloc len memcpy..

To ARC or not to ARC? What are the pros and cons?

http://stackoverflow.com/questions/8760431/to-arc-or-not-to-arc-what-are-the-pros-and-cons

of id can take a little more thinking about to do correctly. Fancy handling of ObjC varargs can also cause trouble. Most things involving math on an ObjC pointer is trickier. You shouldn't have much of this in any case. You cannot put an id in a struct . This is fairly rare but sometimes it's used to pack data. If you did.. to minimize your use of ObjC . ARC will not work at all on iPhoneOS 3 or Mac OS X 10.5 or earlier. This precludes me from using ARC in many projects. __weak pointers do not work correctly on iOS 4 or Mac OS X 10.6 which is a shame but fairly easy to work around. __weak pointers are great but they're not the #1 selling point.. me from using ARC in many projects. __weak pointers do not work correctly on iOS 4 or Mac OS X 10.6 which is a shame but fairly easy to work around. __weak pointers are great but they're not the #1 selling point of ARC. For 95 of code out there ARC is brilliant and there is no reason at all to avoid it provided you can handle..

Objective-C ARC: strong vs retain and weak vs assign

http://stackoverflow.com/questions/8927727/objective-c-arc-strong-vs-retain-and-weak-vs-assign

are there any differences between strong vs retain and weak vs assign From my understanding the only difference here is that weak will assign nil to the pointer while assign won't which means the program will crash when I send a message to the pointer once it's been released. But if I use weak this won't ever happen because.. the only difference here is that weak will assign nil to the pointer while assign won't which means the program will crash when I send a message to the pointer once it's been released. But if I use weak this won't ever happen because message send to nil won't do anything. I don't know about any differences between strong..

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

bytesPerRow size_t byteCount size_t pixelCount CGContextRef context CGColorSpaceRef colorSpace UInt8 pixelByteData A pointer to an array of RGBA bytes in memory RPVW_RGBAPixel pixelData The pixel struct with alpha in this version typedef struct.. space. CGRect rect 0 0 self.size.width self.size.height CGContextDrawImage context rect self.CGImage Now we can get a pointer to the image pixelData associated with the bitmap context. pixelData RGBAPixel CGBitmapContextGetData context return pixelData.. bitmapData Buffer holding raw pixel data copied from Quartz CGImage held in receiver self UInt8 pixelByteData A pointer to the first pixel element in an array RGBPixel pixelData Step 4. Subclass code I put in a method named bitmap to return..

OpenGL ES iPhone - drawing anti aliased lines

http://stackoverflow.com/questions/1813035/opengl-es-iphone-drawing-anti-aliased-lines

here http research.microsoft.com en us um people hoppe overdraw.pdf You could do something along this way Colors is a pointer to unsigned bytes 4 per color . Should alternate in opacity. glColorPointer 4 GL_UNSIGNED_BYTE 0 colors glEnableClientState.. Should alternate in opacity. glColorPointer 4 GL_UNSIGNED_BYTE 0 colors glEnableClientState GL_COLOR_ARRAY points is a pointer to floats 2 per vertex glVertexPointer 2 GL_FLOAT 0 points glEnableClientState GL_VERTEX_ARRAY glDrawArrays GL_TRIANGLE_STRIP..

Fast and Lean PDF Viewer for iPhone / iPad / iOs - tips and hints?

http://stackoverflow.com/questions/3889634/fast-and-lean-pdf-viewer-for-iphone-ipad-ios-tips-and-hints

you can especially if they will be using memory beware of leaving contexts open though Recycle page objects by doing pointer swaps or destroy unused views Close any open Contexts as soon as you don't need them on receiving memory warnings release..

performSelector may cause a leak because its selector is unknown

http://stackoverflow.com/questions/7017281/performselector-may-cause-a-leak-because-its-selector-is-unknown

selector _controller selector Explanation What's going on here is you're asking the controller for the C function pointer for the method corresponding to the controller. All objects respond to methodForSelector and it works through some lower.. lower level Objective C runtime methods so you could do this directly with the runtime API as well . These function pointers are called IMP s and are simple typedef ed function pointers id IMP id SEL ... 1 . This may be close to the actual method.. directly with the runtime API as well . These function pointers are called IMP s and are simple typedef ed function pointers id IMP id SEL ... 1 . This may be close to the actual method signature of the method but will not always match exactly...

To ARC or not to ARC? What are the pros and cons?

http://stackoverflow.com/questions/8760431/to-arc-or-not-to-arc-what-are-the-pros-and-cons

about to do correctly. Fancy handling of ObjC varargs can also cause trouble. Most things involving math on an ObjC pointer is trickier. You shouldn't have much of this in any case. You cannot put an id in a struct . This is fairly rare but sometimes.. not work at all on iPhoneOS 3 or Mac OS X 10.5 or earlier. This precludes me from using ARC in many projects. __weak pointers do not work correctly on iOS 4 or Mac OS X 10.6 which is a shame but fairly easy to work around. __weak pointers are great.. pointers do not work correctly on iOS 4 or Mac OS X 10.6 which is a shame but fairly easy to work around. __weak pointers are great but they're not the #1 selling point of ARC. For 95 of code out there ARC is brilliant and there is no reason..

Objective-C ARC: strong vs retain and weak vs assign

http://stackoverflow.com/questions/8927727/objective-c-arc-strong-vs-retain-and-weak-vs-assign

strong vs retain and weak vs assign From my understanding the only difference here is that weak will assign nil to the pointer while assign won't which means the program will crash when I send a message to the pointer once it's been released. But.. weak will assign nil to the pointer while assign won't which means the program will crash when I send a message to the pointer once it's been released. But if I use weak this won't ever happen because message send to nil won't do anything. I don't..

• point.x
• point.y
• point1
• point1.x
• point1.y
• point2
• point2.x
• point2.y
• pointarray
• pointed
• pointer
• pointers
• pointing
• pointinside
• pointless
• pointpath
• points.count
• points
• pointsordered
• pointstring
• pois
• poke
• polaroid
• policies
• policy
• poll
• polling
• poly1
• poly2
• polygon
• polygons
• polygonview.alpha
• polygonview.backgroundcolor
• polygonview
• polyline
• polylines
• pool
• pools
• poor
• poorly
• pop
• popover
• popovercontent
• popovercontroller
• popovers
• popoverview
• popped
• popping
• pops
• poptime
• poptorootviewcontrolleranimated
• poptoviewcontroller
• popular
• populate
• populated
• populates
• populating
• popup
• popups
• popviewcontroller
• popviewcontrolleranimated
• port
• portable
• portal
• ported
• porting
• portion
• portions
• portrait.css
• portrait