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"""Selection-buffer handling code
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This code is resonsible for turning gluint *
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arrays into structured representations for use
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def uintToLong( value ):
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# array type without a uint, so represented as an int
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value = (value & 0x7fffffff) + 0x80000000
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class GLSelectRecord( object ):
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"""Minimalist object for storing an OpenGL selection-buffer record
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Provides near and far as *float* values by dividing by
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self.DISTANCE_DIVISOR (2**32-1)
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Depth values (which are in the range [0,1]) are multiplied by
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2^32 - 1, before being placed in the hit record.
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Names are unmodified, so normally are slices of the array passed in
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to GLSelectRecord.fromArray( array )
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DISTANCE_DIVISOR = float((2L**32)-1)
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__slots__ = ('near','far','names')
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def fromArray( cls, array, total ):
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"""Produce list with all records from the array"""
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arrayLength = len(array)
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for item in xrange( total ):
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if index + 2 >= arrayLength:
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names = map(uintToLong, array[index+3:index+3+count])
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result.append( cls( near, far, names ) )
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fromArray = classmethod( fromArray )
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def __init__( self, near, far, names ):
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"""Initialise/store the values"""
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self.near = self.convertDistance( near )
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self.far = self.convertDistance( far )
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def convertDistance( self, value ):
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"""Convert a distance value from array uint to 0.0-1.0 range float"""
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return uintToLong( value ) / self.DISTANCE_DIVISOR
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def __getitem__( self, key ):
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"""Allow for treating the record as a three-tuple"""
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if isinstance( key, (int,long)):
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return (self.near,self.far,self.names)[key]
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elif key in self.__slots__:
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return getattr( self, key )
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except AttributeError, err:
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raise KeyError( """Don't have an index/key %r for %s instant"""%(
b'\\ No newline at end of file'
added
removed
GL/selection.py.bak
