glkit

I'm having trouble converting my OpenGL scene coordiates to my screen coordinates. I thought I needed to multiply my coordinates with the modelview matrix then with the projection matrix to get the ndc. But i'm getting weird coordinates. Here is my piece of code GLKVector3 coor = GLKVector3Make(point.x, point.y, 0); GLKMatrix4 modelview = GLKMatrix4MakeWithArray(glProjectionMatrix); GLKMatrix4 projetion = GLKMatrix4MakeWithArray(modelViewMatrix.data); GLKVector3 eyeCoor = GLKMatrix4MultiplyVector3(modelview, coor); GLKVector3 ndcCoor = GLKMatrix4MultiplyVector3(projetion,eyeCoor); CGPoint p =

The iOS 5 documentation reveals that GLKMatrix4MakeLookAt operates the same as gluLookAt . The definition is provided here: static __inline__ GLKMatrix4 GLKMatrix4MakeLookAt(float eyeX, float eyeY, float eyeZ, float centerX, float centerY, float centerZ, float upX, float upY, float upZ) { GLKVector3 ev = { eyeX, eyeY, eyeZ }; GLKVector3 cv = { centerX, centerY, centerZ }; GLKVector3 uv = { upX, upY, upZ }; GLKVector3 n = GLKVector3Normalize(GLKVector3Add(ev, GLKVector3Negate(cv))); GLKVector3 u = GLKVector3Normalize(GLKVector3CrossProduct(uv, n)); GLKVector3 v = GLKVector3CrossProduct(n, u);

What should be the difference, purpose wise, between these two methods in my render loop? Apple has this to say.... About update() The view controller calls its delegate’s glkViewControllerUpdate: method. Your delegate should update frame data that does not involve rendering the results to the screen. About drawInRect: the GLKView object makes its OpenGL ES context the current context and binds its framebuffer as the target for OpenGL ES rendering commands. Your delegate method should then draw the view’s contents. So basically, when I create a GLKView in my view controller, that controller

I have the below code which I am using for ray tracing. The code works successfully on non-retina iPads, however does not function on the retina iPads. The touch is detected, however the converted point is off to the left and below where it should be. Can anyone suggest how I can update the below to accommodate the retina screen ? - (void)handleTap: (UITapGestureRecognizer *)recognizer { CGPoint tapLoc = [recognizer locationInView:self.view]; bool testResult; GLint viewport[4]; glGetIntegerv(GL_VIEWPORT, viewport); float uiKitOffset = 113; //Need to factor in the height of the nav bar + the

I wanted to use OpenGL to do some simple Image processing, so I started off with GLKView . Since I don't need to refresh the view every few seconds, I didn't use the GLKViewController and instead used a normal UIViewController subclass. My question is that do I simply make the viewController's view as a GLKView or do I add the GLKView as a subview of the view controller's view. Since I'm adding a UISlider to the view as well, I think the latter seems better, but I'm not sure. I also need to call setNeedsDisplay on the GLKView on certain occasions. For your rendering, you should really be using

I'm making an iPhone application with OpenGL ES 2.0 using the GLKit. I'm using GLKTextureLoader to load textures synchronously. The problem is that for a certain texture, it fails to load it the first time. It gives this error: The operation couldn’t be completed. (GLKTextureLoaderErrorDomain error 8.) For this error code, the apple documentation says the following: GLKTextureLoaderErrorUncompressedTextureUpload An uncompressed texture could not be uploaded. Available in iOS 5.0 and later. Declared in GLKTextureLoader.h. (not very much). Could I be trying to load the texture while the opengl