Compositing glass with alpha channel and shadow channel
Posted: Wed Feb 15, 2012 9:08 pm
Hi,
I'm trying for the first time to achieve catalogue-style "on-white" images, rendering the "Render", the "Alpha" and the "Shadow". The problem is that through glass, the background is visible in the "Render" and in the "Alpha" the glass area is fully white (no "Alpha" transparency) so I cannot composite the image on the all white background "Shadow" image.
In the scene, there is a wooden structure with a glass top; the structure has a two-polygon floor below, catching the shadows. For the floor, I have "Hidden from Camera" enabled, the floor's material has "Shadow" selected. To illustrate the problem, I have moved the glass partially off the supporting structure, see below:
How would one do this the proper way? Thanks!
PS: Or, is there a way to assign a "clown pass style" white colour to the floor, so the glass would cause the "Alpha" to become transparent (the glass only catching reflections and refractions off the model and HDR environment image)?
I'm trying for the first time to achieve catalogue-style "on-white" images, rendering the "Render", the "Alpha" and the "Shadow". The problem is that through glass, the background is visible in the "Render" and in the "Alpha" the glass area is fully white (no "Alpha" transparency) so I cannot composite the image on the all white background "Shadow" image.
In the scene, there is a wooden structure with a glass top; the structure has a two-polygon floor below, catching the shadows. For the floor, I have "Hidden from Camera" enabled, the floor's material has "Shadow" selected. To illustrate the problem, I have moved the glass partially off the supporting structure, see below:
How would one do this the proper way? Thanks!
PS: Or, is there a way to assign a "clown pass style" white colour to the floor, so the glass would cause the "Alpha" to become transparent (the glass only catching reflections and refractions off the model and HDR environment image)?
