[Bf-committers] Camera, displacement and normals
Gregor Mückl
bf-committers@blender.org
Tue, 20 Jan 2004 15:38:16 +0100
Hi!
I'm currently in the process of building a game engine which allows the player
to look at panoramas, with viewing angles of 180 degrees in the vertical
direction and 360 degrees in the horizontal direction.
I am able to render these panoramas within blender with a small trick: I use
a camera fov of 90 degrees and render 6 images - two along each coordinate
axis - and project them onto a cube which is rendered in realtime. This
method works quite good.
Obviously, the rendered images must fit together seamlessly to create this
illusion. However, I discovered, that when mapping texture output onto the
displacement or normal of a material, the images won't fit as expected. This
is quite disappointing because of this these features aren't available to the
artists working on this game.
Why is this? Does blender's renderer use the camera front vector instead of
the ray direction for this? With a field of view of 90 degrees the angle
between these gets to 45 degrees at the edge centers and even greater than
this at the corners of the image. This would explain the effects I'm seeing.
Is there a reason for doing it the way it is done right now? Would it be a big
deal to alter this behaviour?
Regards,
Gregor