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Misa 57dca99a4e Ax OverlaySurfaceKeyed(), set proper foregroundBuffer blend mode
So, earlier in the development of 2.0, Simon Roth (I presume)
encountered a problem: Oh no, all my backgrounds aren't appearing! And
this is because my foregroundBuffer, which contains all the drawn tiles,
is drawing complete black over it!

So he had a solution that seems ingenius, but is actually really really
hacky and super 100% NOT the proper solution. Just, take the
foregroundBuffer, iterate over each pixel, and DON'T draw any pixel
that's 0xDEADBEEF. 0xDEADBEEF is a special signal meaning "don't draw
this pixel". It is called a 'key'.

Unfortunately, this causes a bug where translucent pixels on tiles
(pixels between 0% and 100% opacity) didn't get drawn correctly. They
would be drawn against this weird blue color.

Now, in #103, I came across this weird constant and decided "hey, this
looks awfully like that weird blue color I came across, maybe if I set
it to 0x00000000, i.e. complete and transparent black, the issue will be
fixed". And it DID appear to be fixed. However, I didn't look too
closely, nor did I test it that much, and all that ended up doing was
drawing the pixels against black, which more subtly disguised the
problem with translucent pixels.

So, after some investigation, I noticed that BlitSurfaceColoured() was
drawing translucent pixels just fine. And I thought at the time that
there was something wrong with BlitSurfaceStandard(), or something.
Further along later I realized that all drawn tiles were passing through
this weird OverlaySurfaceKeyed() function. And removing it in favor of a
straight SDL_BlitSurface() produced the bug I mentioned above: Oh no,
all the backgrounds don't show up, because my foregroundBuffer is
drawing pure black over them!

Well... just... set the proper blend mode for foregroundBuffer. It
should be SDL_BLENDMODE_BLEND instead of SDL_BLENDMODE_NONE.

Then you don't have to worry about your transparency at all. If you did
it right, you won't have to resort this hacky color-keying business.

*sigh*
2020-08-06 22:10:30 -04:00
.github Mention the in-game credits for the Legal Stuff 2020-04-24 12:52:11 -04:00
desktop_version Ax OverlaySurfaceKeyed(), set proper foregroundBuffer blend mode 2020-08-06 22:10:30 -04:00
mobile_version Fix 1x1 quicksand collision optimization not working 2020-05-13 08:16:34 -04:00
third_party Remove TinyXML-1 2020-06-12 15:08:29 -04:00
tools Adding original mapping tools for the sake of completeness 2020-01-12 19:49:24 +01:00
.gitattributes fix actionscript misclassified as angelscript 2020-01-12 15:18:45 -05:00
License exceptions.md Added Haiku links 2020-02-05 15:59:51 +01:00
LICENSE.md Updated link to Make and Play edition 2020-01-13 19:37:50 +01:00
README.md Update README.md 2020-01-10 17:45:29 +01:00

This is the source code to VVVVVV, version 2.0+. For more context about this release, see the announcement on Terry's blog!

License

VVVVVV's source code is made available under a custom license. See LICENSE.md for more details.

In general, if you're interested in creating something that falls outside the license terms, get in touch with Terry and we'll talk about it!

Authors

Versions

There are two versions of the VVVVVV source code available - the desktop version (based on the C++ port, and currently live on Steam), and the mobile version (based on a fork of the original flash source code, and currently live on iOS and Android).