[Bf-committers] [Bf-blender-cvs] SVN commit: /data/svn/bf-blender [57433] trunk/blender/release/scripts/ modules/bpy_extras/object_utils.py: handy function for getting the 2d camera coords for a worldspace location.

[Brecht Van Lommel]

"world_to_camera_view" would be good I think.

On Thu, Jun 13, 2013 at 5:24 PM, Campbell Barton <ideasman42 at gmail.com> wrote:
> Fair point, not really a fan of `ndc space`, though I can't think of
> one I'm especially happy with either...
>
> other possibilities ...
> world_to_view2d (except it returns z component)
> world_to_camera_frame (since it uses camera framing functions, though
> this is more of a detail)
> world_to_view_uvw
> world_to_render ?
>
> On Fri, Jun 14, 2013 at 12:06 AM, Brecht Van Lommel
> <brechtvanlommel at pandora.be> wrote:
>> Nitpick about the terminology used here. "Camera space" usually refers
>> to the coordinates when transformed by the camera matrix but without
>> any perspective transformation applied, so I would say "2D camera
>> space coords" here. OpenGL and Renderman would call the result of this
>> function Normalized Device Coordinates, though I'm not sure if there
>> is a common name for the space, maybe "NDC space".
>>
>> On Thu, Jun 13, 2013 at 3:51 PM, Campbell Barton <ideasman42 at gmail.com> wrote:
>>> Revision: 57433
>>>           http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=57433
>>> Author:   campbellbarton
>>> Date:     2013-06-13 13:51:01 +0000 (Thu, 13 Jun 2013)
>>> Log Message:
>>> -----------
>>> handy function for getting the 2d camera coords for a worldspace location.
>>>
>>>  bpy_extras.object_utils.world_to_camera(scene, obj, coord)
>>>
>>> Modified Paths:
>>> --------------
>>>     trunk/blender/release/scripts/modules/bpy_extras/object_utils.py
>>>
>>> Modified: trunk/blender/release/scripts/modules/bpy_extras/object_utils.py
>>> ===================================================================
>>> --- trunk/blender/release/scripts/modules/bpy_extras/object_utils.py    2013-06-13 13:09:32 UTC (rev 57432)
>>> +++ trunk/blender/release/scripts/modules/bpy_extras/object_utils.py    2013-06-13 13:51:01 UTC (rev 57433)
>>> @@ -25,6 +25,7 @@
>>>      "object_add_grid_scale",
>>>      "object_add_grid_scale_apply_operator",
>>>      "object_image_guess",
>>> +    "world_to_camera",
>>>      )
>>>
>>>
>>> @@ -265,3 +266,40 @@
>>>                          if image is not None:
>>>                              return image
>>>      return None
>>> +
>>> +
>>> +def world_to_camera(scene, obj, coord):
>>> +    """
>>> +    Returns the 2d camera space coords for a 3d point.
>>> +
>>> +    Where (0, 0) is the bottom left and (1, 1) is the top right of the camera frame.
>>> +    values outside 0-1 are also supported.
>>> +
>>> +    Takes shift-x/y, lens angle and sensor size into account
>>> +    as well as perspective/ortho projections.
>>> +
>>> +    :arg scene: Scene to use for frame size.
>>> +    :type scene: :class:`bpy.types.Scene`
>>> +    :arg obj: Camera object.
>>> +    :type obj: :class:`bpy.types.Object`
>>> +    :arg coord: World space location.
>>> +    :type coord: :class:`mathutils.Vector`
>>> +    :return: normalized 2d vector.
>>> +    :rtype: :class:`mathutils.Vector`
>>> +    """
>>> +
>>> +    co_local = obj.matrix_world.normalized().inverted() * coord
>>> +
>>> +    camera = obj.data
>>> +    frame = [-v for v in camera.view_frame(scene=scene)[:3]]
>>> +    if camera.type != 'ORTHO':
>>> +        frame = [(v / -v.z) * co_local.z for v in frame]
>>> +
>>> +    min_x, max_x = frame[1].x, frame[2].x
>>> +    min_y, max_y = frame[0].y, frame[1].y
>>> +
>>> +    x = (co_local.x - min_x) / (max_x - min_x)
>>> +    y = (co_local.y - min_y) / (max_y - min_y)
>>> +
>>> +    from mathutils import Vector
>>> +    return Vector((x, y))
>>>
>>> _______________________________________________
>>> Bf-blender-cvs mailing list
>>> Bf-blender-cvs at blender.org
>>> http://lists.blender.org/mailman/listinfo/bf-blender-cvs
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> http://lists.blender.org/mailman/listinfo/bf-committers
>
>
>
> --
> - Campbell
> _______________________________________________
> Bf-committers mailing list
> Bf-committers at blender.org
> http://lists.blender.org/mailman/listinfo/bf-committers