Blocky Textures around object, Blender render artifacts, possible causes? I'm getting weird render artifacts around the edge of a cylinder on the floor, blocky areas that look low-res:


(Edit) Image A: Blocky Textures behind the cylinder

Rendering from other angles shows the same render artifacts. Seemingly around the render box intersecting both the cylinder and floor.

I've tried changing anti-aliasing and other settings with no effect.


(Edit) Image B: Outliner, Viewport, and Render Settings

I'm at a loss. Any ideas?

Other Info:
   Blender v2.76. 
   Blender Render.
   This floor texture is rather large, 12.3 MB file and 4288 x 2848.
   But artifacts happen with other (smaller) textures as well.
The problem was: assigning a UV Map to the Cylinder was somehow messing up the floor's texture or UV Map. I don't know why. But I was able to clear the artifacts from the render:

I fixed it by selecting the floor --> Edit Mode, and applying a UV Map to it, via the left panel (Shading / UVs tab) --> UVs section --> Unwrap. So both the Cylinder and floor have their own UV Maps.



I don't know why changing the cylinder created artifacts on the floor; they are two different objects, two different UV Maps, two different materials, two different textures. But this solution worked for me!