notes.txt

##Buffer

domain_map = self.group_map[group]

key = (formats, mode, indexed)
try:
    domain = domain_map[key]
except KeyError:
    # Create domain

A domain only knows its formats (and wether it is indexed or not by virtue of which type it is an instance of)
modes are kept seperate through the key

Formats are like `v3f/stream` that get parsed into attributes within the domain

##Domain

instantiated with list of tuples (AbstractAttribute, usage(static/dynamic/etc), and vob(True/False)

Domains have an alloc and dealloc through their allocator

Each attribute is assigned a buffer, which is a vertexbuffer.MappableVertexBufferObject if 
  possible (easily possible) and desired, or a vertexbuffer.VertexArray.

(MappableVertexBufferObject has a system-memory backed store, while VertexArray does not.)

These seperate attribute buffers are sized to all contain the same number of elements:
  size of ctype * number of dimensions in vector * allocator.capacity

Domain stores these as domain.buffer_attributes = [(this_buffer, attribute)], and also in the dict:
  attribute.names, keyed by the attribute name string 


## VertexList
A vertex list gets its colors, vertices, etc through setters and getters by getting that 
attribute's buffer from it's domain and using attribute.get_region with it's own start and count.

get_region gets data like:

    '''
    notes from __init__
    self.count = count #assert count in (1, 2, 3, 4), 'Component count out of range'
    self.align = ctypes.sizeof(self.c_type)
    self.size = count * self.align
    self.stride = self.size #probably different for interleaved...
    self.offset = 0
    '''


    byte_start = self.stride * start
    byte_size = self.stride * count
    array_count = self.count * count # num of elements per vector * number of vectors requested == num of ctypes to get
    if self.stride == self.size or not array_count:
        # non-interleaved
        ptr_type = ctypes.POINTER(self.c_type * array_count)
        return buffer.get_region(byte_start, byte_size, ptr_type)
    else:
        # interleaved
        # Elliot: more complicated. Comments in VertexDomain __init__ lead me to assume this is only for static attributes.