Fix glow in Inventory

[miskatonicstudio]

There seems to be an issue with Viewport node: if background is set to transparent, the glow is gone. Probably the best solution is to report the issue and wait for Godot devs to fix this one.

Other solutions:

• set a background color/image for Inventory (this would ruin nice 3D world background)
• avoid items with emission
• use a texture from Player's camera to set a background for Inventory viewport (this way the background will not be animated)
• use the same camera for 3D world and Inventory (this would cause a lot of issues with proper lighting and order of drawing)

[miskatonicstudio]

Solution no. 3 (non-animated blurred background) seems promising. A shader was already proven to work fast enough for this purpose. Some notes:

• since the shader works fast, maybe the background could be animated? That would require different camera management, to make sure that updated Player view texture doesn't include inventory view
• the size of the blur has to be decided
• no mipmaps are necessary for a blur shader, which makes it easier to manage the Player viewport texture
• for some reason, the 3D quad mesh with a texture is much brighter than Player viewport texture, even though the shader has render mode unshaded etc. ; one of the workaround is to multiply the color by a low value (making the background darker, which actually works pretty well in this case)