# PySoy's bodies.Camera class
#
# Copyright (C) 2006,2007,2008 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
#
# $Id$

cdef class Camera(Body) :
  '''soy.bodies.Camera

    A camera is an invisible object in 3d space through which the scene can
    be rendered through.  It must be attached to a soy.widgets.Projector or
    other rendering class to be activated.
  '''

  ##########################################################################
  #
  # Python Functions
  #

  def __cinit__(self, scene=None,
                position=None, rotation=None, velocity=None,
                model=None, shape=None,
                wireframe=0, 
                *args, **keywords) :
    cdef int _i
    self._fovy = 45.0
    self._znear  = 1.0
    self._zfar   = 100.0
    self.mass = 0
    self._wire = wireframe
    self._rpt = 0
    for _i from 0 <= _i < 16 :
      self._rtimes[_i] = 0.0


  ############################################################################
  #
  # Properties
  #

  property fps :
    def __get__(self) :
      cdef double f1, f2
      f2 = self._rtimes[self._rpt]
      f1 = self._rtimes[(self._rpt + 1) % 16]
      if f1 == 0.0 or f2 == 0.0 or f1 == f2 :
        return 0.0
      else :
        return 1 / (f2 - f1) * 15


  property wireframe :
    def __get__(self) :
      return self._wire
    def __set__(self,value) :
      self._wire = value


  property lens :
    '''Camera Lens

    This is the (vertical) angle which the lens can view.  Defaults to 45.0
    '''
    def __get__(self) :
      return self._fovy

    def __set__(self, value) :
      self._fovy = value


  property direction :
    '''Camera Direction
    
    Direction in which camera is looking
    '''
    def __get__(self) :
      return ( self._rotation[2], self._rotation[6], self._rotation[10] )


  property right :
    '''Camera Right
    
    Direction of the 'right' side of the camera
    '''
    def __get__(self):
      return ( self._rotation[0], self._rotation[4], self._rotation[8] )


  property up :
    '''Camera Up
    
    Direction of the up vector of the camera
    '''
    def __get__(self):
      return ( self._rotation[1], self._rotation[5], self._rotation[9] )


  ############################################################################
  #
  # WindowLoop Functions
  #

  cdef void _project(self, gl.GLdouble _aspect) :
    cdef gl.GLfloat  _mtx[16]
    #
    # Bail now if in the abyss
    if self._scene is None :
      return
    #
    # Check if wireframe mode is turned on
    if self._wire == 1 :
      #gl.glEnable (gl.GL_LINE_SMOOTH)
      #gl.glEnable (gl.GL_BLEND)
      #gl.glBlendFunc (gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)    ## Anti-Aliasing maybe?
      #gl.glHint (gl.GL_LINE_SMOOTH_HINT, gl.GL_DONT_CARE)
      #gl.glLineWidth (3)
      gl.glPolygonMode(gl.GL_FRONT_AND_BACK, gl.GL_LINE)
    else :
      gl.glPolygonMode(gl.GL_FRONT_AND_BACK, gl.GL_FILL)
      #gl.glDisable (gl.GL_LINE_SMOOTH)
      #gl.glDisable (gl.GL_BLEND)
      #gl.glBlendFunc (gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)
      #gl.glHint (gl.GL_LINE_SMOOTH_HINT, gl.GL_DONT_CARE)
      #gl.glLineWidth (1)
    #
    # Now we apply an inverse matrix to translate to the Scene's origin
    gl.glMatrixMode(gl.GL_MODELVIEW)
    gl.glLoadIdentity()
    _mtx[0]  = self._rotation[0]
    _mtx[1]  = self._rotation[1]
    _mtx[2]  = self._rotation[2]
    _mtx[3]  = 0.0
    _mtx[4]  = self._rotation[4]
    _mtx[5]  = self._rotation[5]
    _mtx[6]  = self._rotation[6]
    _mtx[7]  = 0.0
    _mtx[8]  = self._rotation[8]
    _mtx[9]  = self._rotation[9]
    _mtx[10] = self._rotation[10]
    _mtx[11] = 0.0
    _mtx[12] = 0.0
    _mtx[13] = 0.0
    _mtx[14] = 0.0
    _mtx[15] = 1.0
    gl.glLoadMatrixf(_mtx)
    gl.glTranslatef(-self._position[0], -self._position[1], -self._position[2])
    self._scene._render(self._fovy, _aspect, self._znear, self._zfar)
    #
    # Framerate calc
    self._rpt = (self._rpt + 1) % 16
    self._rtimes[self._rpt] = soy._internals._time()