SetsulIt doesn't have to be system specific.
Sure, but it will more optimal if it was system specific. However, I like your idea of using a default value for min heap size of 196, since that's still larger but not too large.
SetsulNo, it won't fade any faster. With -5000 it fades, still being rendered until 5000 except with alpha involved, with 0 it'll be fully opaque and just disappear at 5000.
Sorry if my wording was confusing. I meant I wanted it to fade since it will be basically invisible at like 4000 or something, which reduces clutter. With 5000 to 5000, it will still be opaque at 4000, and disappear at 5000.
SetsulYou didn't explain why otherwise the colour buffer would be read and why it would not be read when set to a solid colour.
The driver will see if you call a clear on the color buffer for that frame, and if so, then it won't read what you last drew to the buffer again.
SetsulYou didn't explain how writing to the colour buffer instead of reading from it would speed things up.
On modern hardware, clearing the color buffer is faster than the read. Sure, it would be most ideal to tell the driver to just invalidate the last buffer, but as far as I can tell, the Source Engine wasn't written for that.
SetsulYou didn't explain why that would happen on TBIMR like Maxwell/Pascal but not on standard IMR.
Because in order to stitch tiles together efficiently, the GPU has to have a different understanding of the final scene for the next frame. It doesn't know if the draw this upcoming frame will draw on every pixel, so it preemptively reads from the last buffer.