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copied!<p>This is a common game development pattern.</p> <p>The usual approach is to cook the data in an offline pre-process step. The resulting blobs can be streamed in with minimal overhead. The blobs are platform dependent and should contain the proper alignment & endian-ness of the target platform.</p> <p>At runtime, you can simply cast a pointer to the in-memory blob file. You can deal with nested structures as well. If you keep a table of contents with offsets to all the pointer values within the blob, you can then fix-up the pointers to point to the proper address. This is similar to how dll loading works.</p> <p>I've been working on a ruby library, <a href="http://github.com/hyperlogic/bbq" rel="nofollow noreferrer">bbq</a>, that I use to cook data for my iphone game. </p> <p>Here's the memory layout I use for the blob header:</p> <pre><code>// Memory layout // // p begining of file in memory. // p + 0 : num_pointers // p + 4 : offset 0 // p + 8 : offset 1 // ... // p + ((num_pointers - 1) * 4) : offset n-1 // p + (num_pointers * 4) : num_pointers // again so we can figure out // what memory to free. // p + ((num_pointers + 1) * 4) : start of cooked data // </code></pre> <p>Here's how I load binary blob file and fix up pointers:</p> <pre><code>void* bbq_load(const char* filename) { unsigned char* p; int size = LoadFileToMemory(filename, &p); if(size <= 0) return 0; // get the start of the pointer table unsigned int* ptr_table = (unsigned int*)p; unsigned int num_ptrs = *ptr_table; ptr_table++; // get the start of the actual data // the 2 is to skip past both num_pointer values unsigned char* base = p + ((num_ptrs + 2) * sizeof(unsigned int)); // fix up the pointers while ((ptr_table + 1) < (unsigned int*)base) { unsigned int* ptr = (unsigned int*)(base + *ptr_table); *ptr = (unsigned int)((unsigned char*)ptr + *ptr); ptr_table++; } return base; } </code></pre> <p>My <a href="http://github.com/hyperlogic/bbq" rel="nofollow noreferrer">bbq</a> library isn't quite ready for prime time, but it could give you some ideas on how to write one yourself in python.</p> <p>Good Luck!</p>

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