It took several months to go through the process of contacting TCL about this issue and getting a ticket escalated to their engineers, but here's the problem in a nutshell:
On the previous series (R615) in 'computer mode', any integer resolution of the native display image is properly upscaled via nearest neighbor, which is great for retro-gamers that want the absolute sharpest digital image as possible for various FPGA or OSSC solutions. So what's an example of nearest neighbor integer scaling? Lets take 1280x720p. If you multiply that by 3x, you get the native resolution of the TCL display (3840x2160). So ideally for retro-gaming this source resolution of 1280x720 is simply upscaled via nearest neighbor, which gives razor-sharp pixel edges. Retro-gamers LOVE this.
However when the R625 series came out, nearest neighbor upscaling was removed from computer mode (or any other mode for that matter), making for soft edges and rounded corners on pixels. This is very disappointing. So at any rate, after several months of back and forth from TCL on my ticket for this issues, they finally got back to me and stated the following:
"Start a case with Roku to influence them to change the scaling method back for the Reno builds."
Now I have no idea how to 'influence' Roku to do that, but I figured I might as well post here to get started. Who do I have to beg to see the light on why this is so important for retro-gamers? I'm only requesting this optional scaling for Computer Mode, or even better would be if Roku added a "Retro-Gamer" mode, where it's similar to "Game Mode" but includes nearest neighbor scaling for integer scales of the TCL native display resolution. Most specifically, 1280x720, and 1920x1080.
Much appreciated for your time on this, and if Roku doesn't read these posts, hopefully someone can put me in touch with someone from Roku that will listen to this request for a firmware update.
I have a 43" TCL Roku TV that I use as a computer monitor and I am wondering the same thing.
Actually, through this post you have done the rest of the ROKU TV user community a great service. From the dialog you report with the TCL engineers, it is obvious that they are only in charge of the hardware. All internal operations are now controlled by the ROKU OS, and so ANY malfunctions of the sorts described in thread after thread in this forum can be laid directly at the feet of ROKU and no one else.
The most disappointing thing is that it will happily turn off filtering in 3840 x 2160 mode. All I want is for the TV to do less work than it is currently doing.