# PySoy's materials._normalisationCubemap function
#
# Copyright (C) 2006,2007,2008,2009 PySoy Group
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU Affero General Public License as published
#  by the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU Affero General Public License for more details.
#
#  You should have received a copy of the GNU Affero General Public License
#  along with this program; if not, see http://www.gnu.org/licenses
#
# $Id: _normalisationCubemap.pym 1393 2008-12-31 23:51:25Z ArcRiley $

cimport stdlib
cimport soy.textures

cdef void _normalisationCubemap(soy.textures.Texture _cubemap) :
  cdef int _i, _j
  cdef float _length
  cdef float _vector[3]
  cdef unsigned char* _ptr
  #
  ########################################
  #
  # call the texture's _resize function
  #
  # This sets up many of the textures parameters and mallocs _texels
  # In the future the first array (bytes) should be 4 for float, which should
  # not only speed this up a bit but provide more accurate normalisation
  #
  _cubemap._resize(1, 3, 32, 32, 6)
  #
  ########################################
  #
  # initialize _ptr to the texture's _texels
  #
  # we use _ptr to scan over the _texels data as it's generated, which is
  # slightly faster than using _ptr as an int and adding it many times, ie:
  #   _ptr[0] = <unsigned char> (_vector[0] * 255)
  #   _ptr[1] = <unsigned char> (_vector[1] * 255)
  #   _ptr[2] = <unsigned char> (_vector[2] * 255)
  #   _ptr = _ptr + 3
  #
  #  vs the slower
  #
  #   _cubemap._texels[_ptr  ] = <unsigned char> (_vector[0] * 255)
  #   _cubemap._texels[_ptr+1] = <unsigned char> (_vector[0] * 255)
  #   _cubemap._texels[_ptr+2] = <unsigned char> (_vector[0] * 255)
  #   _ptr = _ptr + 3
  # 
  _ptr = _cubemap._texels
  #
  ############################################################################
  #
  # This following code was derived from "Normalisation Cube Map.cpp"
  # from http://paulsprojects.net/tutorials/simplebump/simplebump.html
  #
  # Copyright (c) 2006, Paul Baker
  # All rights reserved.
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  #  * Redistributions of source code must retain the above copyright notice,
  #    this list of conditions and the following disclaimer.
  #  * Redistributions in binary form must reproduce the above copyright
  #    notice, this list of conditions and the following disclaimer in the
  #    documentation and/or other materials provided with the distribution.
  #  * Neither the name of paulsprojects.net nor the names of its contributors
  #    may be used to endorse or promote products derived from this software
  #    without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  # POSSIBILITY OF SUCH DAMAGE.
  #
  ########################################
  #
  # +X
  # 
  for _j from 0 < _j <= 32:
    for _i from 0 < _i <= 32:
      _vector[0] =  16.0
      _vector[1] = -(_j + 0.5 - 16.0)
      _vector[2] = -(_i + 0.5 - 16.0)

      _length = stdlib.sqrtf( _vector[0] * _vector[0] + 
                              _vector[1] * _vector[1] + 
                              _vector[2] * _vector[2] )

      _vector[0] = 0.5 * (_vector[0] / _length) + 0.5
      _vector[1] = 0.5 * (_vector[1] / _length) + 0.5
      _vector[2] = 0.5 * (_vector[2] / _length) + 0.5

      _ptr[0] = <unsigned char> (_vector[0] * 255)
      _ptr[1] = <unsigned char> (_vector[1] * 255)
      _ptr[2] = <unsigned char> (_vector[2] * 255)
      _ptr = _ptr + 3
  #
  ########################################
  #
  # -X
  # 
  for _j from 0 < _j <= 32:
    for _i from 0 < _i <= 32:
      _vector[0] = -16.0
      _vector[1] = -(_j + 0.5 - 16.0)
      _vector[2] =  (_i + 0.5 - 16.0)

      _length = stdlib.sqrtf( _vector[0] * _vector[0] + 
                              _vector[1] * _vector[1] + 
                              _vector[2] * _vector[2] )

      _vector[0] = 0.5 * (_vector[0] / _length) + 0.5
      _vector[1] = 0.5 * (_vector[1] / _length) + 0.5
      _vector[2] = 0.5 * (_vector[2] / _length) + 0.5

      _ptr[0] = <unsigned char> (_vector[0] * 255)
      _ptr[1] = <unsigned char> (_vector[1] * 255)
      _ptr[2] = <unsigned char> (_vector[2] * 255)
      _ptr = _ptr + 3
  #
  ########################################
  #
  # +Y
  # 
  for _j from 0 < _j <= 32:
    for _i from 0 < _i <= 32:
      _vector[0] =  (_i + 0.5 - 16.0)
      _vector[1] =  16.0
      _vector[2] =  (_j + 0.5 - 16.0)

      _length = stdlib.sqrtf( _vector[0] * _vector[0] + 
                              _vector[1] * _vector[1] + 
                              _vector[2] * _vector[2] )

      _vector[0] = 0.5 * (_vector[0] / _length) + 0.5
      _vector[1] = 0.5 * (_vector[1] / _length) + 0.5
      _vector[2] = 0.5 * (_vector[2] / _length) + 0.5

      _ptr[0] = <unsigned char> (_vector[0] * 255)
      _ptr[1] = <unsigned char> (_vector[1] * 255)
      _ptr[2] = <unsigned char> (_vector[2] * 255)
      _ptr = _ptr + 3
  #
  ########################################
  #
  # -Y
  # 
  for _j from 0 < _j <= 32:
    for _i from 0 < _i <= 32:
      _vector[0] =  (_i + 0.5 - 16.0)
      _vector[1] = -16.0
      _vector[2] = -(_j + 0.5 - 16.0)

      _length = stdlib.sqrtf( _vector[0] * _vector[0] + 
                              _vector[1] * _vector[1] + 
                              _vector[2] * _vector[2] )

      _vector[0] = 0.5 * (_vector[0] / _length) + 0.5
      _vector[1] = 0.5 * (_vector[1] / _length) + 0.5
      _vector[2] = 0.5 * (_vector[2] / _length) + 0.5

      _ptr[0] = <unsigned char> (_vector[0] * 255)
      _ptr[1] = <unsigned char> (_vector[1] * 255)
      _ptr[2] = <unsigned char> (_vector[2] * 255)
      _ptr = _ptr + 3
  #
  ########################################
  #
  # +Z
  # 
  for _j from 0 < _j <= 32:
    for _i from 0 < _i <= 32:
      _vector[0] =  (_i + 0.5 - 16.0)
      _vector[1] = -(_j + 0.5 - 16.0)
      _vector[2] =  16.0

      _length = stdlib.sqrtf( _vector[0] * _vector[0] + 
                              _vector[1] * _vector[1] + 
                              _vector[2] * _vector[2] )

      _vector[0] = 0.5 * (_vector[0] / _length) + 0.5
      _vector[1] = 0.5 * (_vector[1] / _length) + 0.5
      _vector[2] = 0.5 * (_vector[2] / _length) + 0.5

      _ptr[0] = <unsigned char> (_vector[0] * 255)
      _ptr[1] = <unsigned char> (_vector[1] * 255)
      _ptr[2] = <unsigned char> (_vector[2] * 255)
      _ptr = _ptr + 3
  #
  ########################################
  #
  # -Z
  # 
  for _j from 0 < _j <= 32:
    for _i from 0 < _i <= 32:
      _vector[0] = -(_i + 0.5 - 16.0)
      _vector[1] = -(_j + 0.5 - 16.0)
      _vector[2] = -16.0

      _length = stdlib.sqrtf( _vector[0] * _vector[0] + 
                              _vector[1] * _vector[1] + 
                              _vector[2] * _vector[2] )

      _vector[0] = 0.5 * (_vector[0] / _length) + 0.5
      _vector[1] = 0.5 * (_vector[1] / _length) + 0.5
      _vector[2] = 0.5 * (_vector[2] / _length) + 0.5

      _ptr[0] = <unsigned char> (_vector[0] * 255)
      _ptr[1] = <unsigned char> (_vector[1] * 255)
      _ptr[2] = <unsigned char> (_vector[2] * 255)
      _ptr = _ptr + 3
  #
  ############################################################################