Background: So I'm working on a raytracer.. for my construction of the spatial partitioning scheme, I initially had some code like this: if (msize <= 2) { // create a leaf node Model **models = new Model*[msize]; for (uint i=0; i<msize; ++i) models[i] = &mlist[i]; *arrayPtr = Node(models, msize); // class Node contai...
I have worked with pointers a lot, but still whenever I work with them, I feel that one might not work the way I expect it to. My mind is not sure as to how they will behave. What do you suggest? I want to learn pointers better. ...
So I'm starting my magic square hw, where I ask the user to enter a odd integer, and it will create a magic square off that. I have to use pointers and arrays as that is all I have learned so far. Not asking how to do the magic square, but what is causing a segmentation fault, im probably not doing pointers to 2d arrays correctly #inclu...
When trying to compile the following code, I am getting a warning that line 18 makes integer from pointer without cast and that 19 and 20 are incompatible types in assignment. I am new to structures in C, and can't seem to figure out what is wrong. #include <stdio.h> struct song { char title[70]; }; struct playlist { stru...
What is the difference b/w struct { float *p; }*ptr=s; *ptr->p++ and (*ptr->p)++; I understand that the former points to the next address while the latter increments the value by 1 but I cannot get how it is happening..... ...
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I have a piece of C code that looks like this: const char (*foo)[2] = bar(); Now bar() is a function that returns a (const void *). How do I properly cast this const pointer? The code produces this warning from GCC : "initialization discards qualifiers from pointer target type". Here are some of my unsuccessful attempts: const char (...
So, for class I'm (constantly re-inventing the wheel) writing a bunch of standard data structures, like Linked Lists and Maps. I've got everything working fine, sort of. Insertion and removal of data works like a charm. But then main ends, my list is deleted, it calls it's dtor and attempts to delete all data inside of it. For some r...
In my programming class, we have struct Time { int hours, min, sec; } We are to create a method to compute the difference between two times: Time *timeDiff(const Time *t1, const Time *t2) I thought I could create the time difference by getting everything in seconds, and then subtracting the two values, but it seems like extra wo...
In C#, it's possible to declare a struct (or class) that has a pointer type member, like this: unsafe struct Node { public Node* NextNode; } Is it ever safe (err.. ignore for a moment that ironic little unsafe flag..) to use this construction? I mean for longterm storage on the heap. From what I understand, the GC is free to move th...
How can I do this? (The following code does NOT work, but I hope it explains the idea.) class MyClass { .... private: int ToBeCalled(int a, char* b); typedef (MyClass::*FuncSig)(int a, char* b); int Caller(FuncSig *func, char* some_string); } I want to call Caller in some way like: Caller(ToBeCalled, "stuff"...
c# struct defined as: [StructLayout(LayoutKind.Sequential)] public struct RecognizeResult { /// float public float similarity; /// char* [MarshalAs(UnmanagedType.LPStr)] public string fileName; } c function signature: void FaceRecognition(RecognizeResult *similarity); //where similar...
I've stumbled onto something I can't figure out, so I think I'm missing something in the greater C++ picture. In short, my question is: how to keep a mutable, non-deletable, possibly NULL instance of an object in a class. The longer version is: I have the following scenario: a bunch of classes (which I can change slightly, but not tho...
Is there any notion of pointer quality in Haskell? == requires things to be deriving Eq, and I have something which contains a (Value -> IO Value), and neither -> nor IO derive Eq. EDIT: I'm creating an interpreter for another language which does have pointer equality, so I'm trying to model this behavior while still being able to use H...
I was wondering if there is any difference in performance when you compare/contrast A) Allocating objects on the heap, putting pointers to those objects in a container, operating on the container elsewhere in the code Ex: std::list<SomeObject*> someList; // Somewhere else in the code SomeObject* foo = new SomeObject(param1, param2); ...
I have a basic question on array and pointer in C/C++. Say I have: Foo* fooPtrArray[4]; How to pass the fooPtrArray into a function? I have tried: int getResult(Foo** fooPtrArray){} // failed int getResult(Foo* fooPtrArray[]){} // failed How can I deal with pointer array? EDIT: I once thought the error msg is from passing the...
A simple question about accessing array information through pointers that I can't seem to figure out. I'm passing a bunch of multi-dimentional arrays into a function. Now they are not dynamic but even if static, I have to pass them as pointers right? (If I'm wrong, please do correct me) So once I do pass them into a function, how do I a...
Its a simple but important question. What are the do's and donts while using a pointers in C and C++ so as to make sure SEGMENTATION FAULT is avoided on AIX? Where char * are preferred over character array? ...
hi there, for the sake of simplicity ill just paste an example instead of my entire code which is a bit huge. while im porting my code to VC++ instead of using GCC i need to rewrite a few inline assembly functions that receive pointers and save values on those pointers. imagine cpuid for example: void cpuid( int* peax, int* pebx, int* ...
An array of pointers to strings is provided as the input. The task is to reverse each string stored in the input array of pointers. I've made a function called reverseString() which reverses the string passed to it. This functions works correctly as far as i know. The strings stored/referenced in the input array of pointers are sent on...