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Old September 11th, 2007   #10 (permalink)
shashClp
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Join Date: Sep 2006
Location: VisualC
Posts: 757
Quote:
Originally Posted by Squall-Leonhart View Post
alpha blending has always been a compatibility feature rather then an enforced feature in most emulators,and should only be used when there is blending issues, on games where there are none, enabling this setting more often then not causes problems like the one in the ideas render, one of the reasons it is now causing issues is because graphics emulation is more perfected so the setting is no longer needed, tell me, do you see any graphical anomalies with it disabled or missing effects, because i am yet to see any.
There is at least one in the left screenshot (both left screenshots), under the sign near the house, and it's blending related. You can check it's fixed on the right one. And by the way, the DS supports alpha blending per se, so calling it a "enforced feature" is basically nonsense, the problem is more complex than you think, because of alpha blending depth write options and auto-ordering of blended polygons, the first being "easy" to emulate as long as there's no invariance between the base polygon and the decal one. The second one is harder due to being unsupported on PC hardware, so it must be done per software. It's doable but slow.

Quote:
Originally Posted by Squall-Leonhart View Post
and another thing lol noone mentioned it killing performance, the problem mentioned was lines appear when alpha blending is enabled.

(...)

there is a performance issue but its not related to alpha blending as you said, nor was i ever mentioning it was
Lines are/were often drawn as degenerate triangles, and more than often decrease performance on certain configurations. That's a fact, not something that can be discussed, check hardware line drawing implementations for some pointers. Anyway, it's not related to the rest of the thread, so I'll just let it be.

Quote:
Originally Posted by Squall-Leonhart View Post
in my experience, when the lines come up when such a setting is on, but don't when it isn't.. then this is indeed a good thing.
It's in fact a bad sign, because the zfighting shows how it's done, and believe me it's one of the worst implemented features of ideas. Zfighting + lines is something graphic coders recognize fast :P
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