RnDr FOX requested a how to for the pic below and for any interest here goes.
Object Mode:
Create a box, preferably a tall one as this seems to help with the "projection" of distance.
Then select all the upright faces and apply the Attribute class/glossyreflector with a Kr setting of 0.95. Then select the bottom face and apply a texture of your choice then do the same for the top face.
You could use a modifier to slightly, slightly taper the box from bottom to top but instead I went into Point Editor to select the top face and slightly, slightly Scale the Face. Place an object within the box then go into...
Scene Mode
Place Object then move camera into a horizontal position and place it in a postion so that you can see inside the box. Normally for a wide angle view I set the FOV to 90 and render it at size 500 x 300. This time FOV is set at default(60 degrees) and the size is 900 x 500.
Before rendering set Scene Attribute to RayDepth integer value 48 and Scene Attribute AmbientOccluder with integer value of 1. Then set Lighting Parameters to Global Intensity of 0 and Ambient Intensity of 2. I can't remember the AA setting but I think it was Random AA of 256 samples.
Lastly : render and done.
That was how I done it but settings should be experimented with.
