1547+ particle rendering issues

ID:2662338
 
Mar 8 2021, 11:39 am
Not a bug
BYOND Version:514.1549
Operating System:Windows 10 Home 64-bit
Web Browser:Chrome 88.0.4324.190
Applies to:Dream Seeker
Status: Not a bug
This is not a bug. It may be an incorrect use of syntax or a limitation in the software. For further discussion on the matter, please consult the BYOND forums.
Descriptive Problem Summary:
1547 particle rendering is wacky
Numbered Steps to Reproduce Problem:
Apply the code snippet below on 1546, then again on 1547+
Code Snippet (if applicable) to Reproduce Problem:
/particles/snow
    width = 500
    height = 500
    count = 2500
    spawning = 20
    bound1 = list(-1000, -300, -1000)
    lifespan = generator("num", 150, 320, NORMAL_RAND)
    fade = 50
    position = generator("box", list(-300,250,0), list(300,300,75))
    gravity = list(0, -1)
    friction = 0.3
    drift = generator("sphere", 0, 2)
    icon = 'snowflake.dmi'
    icon_state = list("snowflake_2" = 1, "snowflake_3" = 1, "snowflake_4" = 1, "snowflake_5" = 1)


Expected Results:
Particles will render the same
Actual Results:
1547 causes pop-in on particles, particles will randomly disappear without fading, particles fall much faster

Having nonjittery edges is nice though

Does the problem occur:
Every time? Or how often?
Yes
In other games?
Yes
In other user accounts?
Yes
On other computers?
Yes

When does the problem NOT occur?
Using pre 1547 versions
Did the problem NOT occur in any earlier versions? If so, what was the last version that worked? (Visit http://www.byond.com/download/build to download old versions for testing.)

Workarounds:
Not using 1547+

Mar 8 2021, 2:06 pm
I'm not sure this is really a bug, because particles in 514.1547 changed their timing so they would behave differently from previous examples. That's probably all you're seeing.

Regardless I need a test case here, and also your bug report needs the version field edited since Beta Bugs always requires the full version number.
Mar 12 2021, 2:55 am
Mar 17 2021, 10:54 am
Lummox JR resolved issue (Not a bug)
Mar 17 2021, 11:01 am
All right, I've finally isolated the problem you were having with particles jumping in and out of existence and I determined it isn't a bug after all.

The reason particles sometimes seem to disappear and then reappear is twofold. First, you're using a sphere for the drift instead of a circle, and the Z coordinate isn't being scaled. Second, the starting Z coordinate can be as high as 75. Thus, some snowflakes are drifting past a Z coordinate where the renderer can see them at all. The Z coord has to be within -100 to 100 to guarantee rendering, although in practice the limit is slightly higher; your snowflakes sometimes escape that limit.