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manage bit fields in vala without going insane.
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(c) Gustav Hartvigsson 2020
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The basic concept of a bitfield is to provide some kind of siple storrage of
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information, that should not take too much space.
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The basic way of doing this is using something like uint8 or uint16,
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which provides us with up to 8 and 16 fields respectivly, with the simplest
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field being 1 bit, up to the one-field type having the full 8bit (256 value)
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or 16bit (65535 values) to work with in one field.
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When defining a bitfiled type you need to consider what fields you need, how
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many values each feald sholud have and how they corrolate to your data.
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lets take the examlpe of a simple game map, where you have information like
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if a tile is travelsable or if only cetain types of units can move over them.
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If we have land units and water units, we could represet that with as little as
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* 00 - Not traverable,
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* 01 - travelable by land units,
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* 10 - travelable by sea units.
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* 11 - traverable by both types of units.
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That means that we have 14 bits left if we use a 16 bit value, or 6 bits left
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if we use an 8 bit value.
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For the sake of argument, we are going to be using an 8 bit value in the
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Tile [0][0][0][0][0][0][0][0]
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* Trav - What sort of traversal is posible on the tile.
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* Tile Set - You four tile sets, you cound switch between them here.
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* Tile Texture - The specific tile texture in the tile set you want to have
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Since each tile on the map is only one 8 bit value, instead of multi byte
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data structures, you will save on memory.
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The nivé solution would be to use a struct or each tile and have the information
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stored in seral bytes and store that in an array, but that would take up 3 times
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as much space, or more if you use other types.
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For basic usage see the example in main.vala.
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int main (int argc, char * argv[]) {
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* The basic concept of a bitmap is to provide some kind of siple storrage of
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* information, that should not take too much space.
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* The basic way of doing this is using something like uint8 or uint16,
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* which provides us with up to 8 and 16 fields respectivly, with the simplest
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* field being 1 bit, up to the one-field type having the full 8bit (256 value)
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* or 16bit (65535 value) to work with in one field.
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* When defining a bitmap type you need to consider what fields you need, how
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* many values each feald sholud have and how they corrolate to your data.
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* Lits take the examlpe of a simple game map, where you have information like
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* if a tile is travelsable or if only cetain
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