packing

I have N items of 2D image data that will be rectangular and I want to pack them into a single power of 2 texture as efficiently as possible. A simple non-efficient and naive implementation of an algorithm to pack these rects would be easy to whip up, but I'm sure people have come up with algorithms to do this as space efficiently as possible. I've found various references to lightmap packing which is similar to what I'm looking for, but the algorithms for lightmapping tend to take non-rectangular images into account which actually complicates things more than I need them to be. Does anyone

During a code review I've come across some code that defines a simple structure as follows: class foo { unsigned char a; unsigned char b; unsigned char c; } Elsewhere, an array of these objects is defined: foo listOfFoos[SOME_NUM]; Later, the structures are raw-copied into a buffer: memcpy(pBuff,listOfFoos,3*SOME_NUM); This code relies on the assumptions that: a.) The size of foo is 3, and no padding is applied, and b.) An array of these objects is packed with no padding between them. I've tried it with GNU on two platforms (RedHat 64b, Solaris 9), and it worked on both. Are the assumptions

I bet somebody has solved this before, but my searches have come up empty. I want to pack a list of words into a buffer, keeping track of the starting position and length of each word. The trick is that I'd like to pack the buffer efficiently by eliminating the redundancy. Example: doll dollhouse house These can be packed into the buffer simply as dollhouse , remembering that doll is four letters starting at position 0, dollhouse is nine letters at 0, and house is five letters at 3. What I've come up with so far is: Sort the words longest to shortest: (dollhouse, house, doll) Scan the buffer

For example, I have a class , class naive { public: char a; long long b; char c; int d; }; and according to my testing program, a to d are built one after another, like a------- bbbbbbbb c---dddd - means unused. Why does not C++ make it tighter, like ac--dddd bbbbbbbb Class and struct members are required by the standard to be stored in memory in the same order in which they are declared. So in your example, it wouldn't be possible for d to appear before b . Also, most architectures prefer that multi-byte types are aligned on 4- or 8-byte boundaries. So all the compiler can do is leave empty