2014/10/15 下午 10:12:22

iphone Programming Glossary: ordinates

Retrieving a pixel alpha value for a UIImage

http://stackoverflow.com/questions/1042830/retrieving-a-pixel-alpha-value-for-a-uiimage

0 width height image CGContextRelease context I then calculate the array index for the given alpha channel using the coordinates from the UIImageView. int byteIndex bytesPerRow uiViewPoint.y uiViewPoint.x bytesPerPixel unsigned char alpha rawData byteIndex.. black transparent area of the image I get non zero values for the alpha channel. Do I need to translate the co ordinates between UIKit and Core Graphics i.e is the y axis inverted Or have I misunderstood premultiplied alpha values Update @Nikolai.. alpha values Update @Nikolai Ruhe's suggestion was key to this. I did not in fact need to translate between UIKit coordinates and Core Graphics coordinates. However after setting the blend mode my alpha values were what I expected CGContextSetBlendMode..

How do I blend two textures with different co-ordinates in OpenGL ES 2.0 on iPhone?

http://stackoverflow.com/questions/12242443/how-do-i-blend-two-textures-with-different-co-ordinates-in-opengl-es-2-0-on-ipho

do I blend two textures with different co ordinates in OpenGL ES 2.0 on iPhone I can blend two textures with different blending modes in the fragment shader when both the.. position 2 GL_FLOAT 0 0 imageVertices glVertexAttribPointer inputTextureCoordinate 2 GL_FLOAT 0 0 textureCoordinates glClearColor 0.0 0.0 0.0 0.0 glClear GL_COLOR_BUFFER_BIT glDrawArrays GL_TRIANGLE_STRIP 0 4 glBindRenderbuffer GL_RENDERBUFFER.. pixelBot iphone ios opengl es opengl es 2.0 textures share improve this question You have to pass 2 texture coordinates to shader and modify shader Add to ObjectiveC glVertexAttribPointer inputTextureCoordinate2 2 GL_FLOAT 0 0 textureCoordinates2..

Cropping an image in iOS using OpenCV face detection

http://stackoverflow.com/questions/14756505/cropping-an-image-in-ios-using-opencv-face-detection

img UIImage imageWithCGImage cropped_img UIImageWriteToSavedPhotosAlbum img self nil nil Am getting the correct co ordinates of faces i . But the problem is only with cropping and setting ROI. Can some one help me in solving it I tried with the.. UIGraphicsEndImageContext return subImage The Image is cropped but Not with actual Co ordinates. My observations 1 Am cropping the image with FaceRect which is returned by Affinetransform. Will this be a reason for wrong.. 1 Am cropping the image with FaceRect which is returned by Affinetransform. Will this be a reason for wrong Co ordinates or its because of bug in my code 2 I couldnt set ROI for an image before setting Affine Transform what is the reason Is..

How do i open Google Maps for directions using coordinates on the iphone

http://stackoverflow.com/questions/1548024/how-do-i-open-google-maps-for-directions-using-coordinates-on-the-iphone

do i open Google Maps for directions using coordinates on the iphone I am using UIMapView to display locations on the iPhone. I want to do a directions from current location.. inform So I will open either the Google Maps application or safari to display it. Can i do this by specifying co ordinates from current location to co ordinates the location of interest I have these longitudes and latitudes. Or do i have to use.. Google Maps application or safari to display it. Can i do this by specifying co ordinates from current location to co ordinates the location of interest I have these longitudes and latitudes. Or do i have to use street addresses If I do have to use..

SQL Query for Performing Radius Search based on Latitude Longitude

http://stackoverflow.com/questions/1727137/sql-query-for-performing-radius-search-based-on-latitude-longitude

circle maths on every row every time you make a query. Personally I would calculate the TopLeft and BottomRight co ordinates of a square which only needs to be crudly calculated using pythagoras with sides equal to the range you are looking for..

iPhone Landscape-Only Utility-Template Application

http://stackoverflow.com/questions/525737/iphone-landscape-only-utility-template-application

controller. Otherwise can you post some code void viewDidLoad After loading the view transform the view so that the co ordinates are right for landscape As described in iPhone Application Programming Guide Weird I'm sure this used to be needed but it..

Is there any framework to highlight text on pdf file after rendering on the iphone

http://stackoverflow.com/questions/5335799/is-there-any-framework-to-highlight-text-on-pdf-file-after-rendering-on-the-iph

which is rendered through the drawLayer . Can any one suggest how I should find a word on a pdf and the position co ordinates of the word on the page Is there any free framework to import or any libraries available After spending more time with google..

View offset by navigation bar

http://stackoverflow.com/questions/7681004/view-offset-by-navigation-bar

bar isn't set to Black Translucent but Black Opaque. To manually correct set self.view.bounds to the right co ordinates in your featured view's viewWillAppear or viewDidLoad if you use manual coordinates viewDidLoad is fine but I think you.. self.view.bounds to the right co ordinates in your featured view's viewWillAppear or viewDidLoad if you use manual coordinates viewDidLoad is fine but I think you need viewWillAppear if you're using parts of self.navigationController like the position..

Navigating a Pdf using UIWebview not working in IOS 5

http://stackoverflow.com/questions/8039367/navigating-a-pdf-using-uiwebview-not-working-in-ios-5

as argument. Here x and y are integer values representing the scrollPosition. If you want to get current x and y co ordinates for webView below is the code which you can use NSInteger x aWebview.scrollView.contentOffSet.x NSInteger y aWebview.scrollView.contentOffset.y..

How to get coordinates using abbyy mobile sdk for iphone

http://stackoverflow.com/questions/9113119/how-to-get-coordinates-using-abbyy-mobile-sdk-for-iphone

to get coordinates using abbyy mobile sdk for iphone I am using sample project of abbyy mobile SDK for iPhone version 4 . using this how can.. sdk for iphone I am using sample project of abbyy mobile SDK for iPhone version 4 . using this how can i get co ordinates of specific word s of an image using the mobile sdk for iphone . I have checked the API reference and found FineRecognizeRegion.. I have checked the API reference and found FineRecognizeRegion Function but do not know how can i use it to get the co ordinates of a specific word s on an image taken by device camera. Please help Thanks in advance iphone ocr abbyy share improve..

heat map on map view in iphone…?

http://stackoverflow.com/questions/9139396/heat-map-on-map-view-in-iphone

share improve this question Well I have found a solution to this.. and this is how I did it.. You need to get the co ordinates of the boundaries of the countries which I got from http thematicmapping.org downloads world_borders.php . you can get the.. using QGIS software from here http hub.qgis.org projects quantum gis wiki Download . Now extract the boundary co ordinates from KML and then use it to draw MKPolygon on the map. and this is how it will look like .. hoping this helps somebody...