2

I've seen a few discussions regarding 'Point Sprites vs Textured Quad Sprites' and the like.

However, one thing confuses me, if I understand correctly, aren't the size of point sprites limited (By a point sprite range)?

I'm fairly new to OpenGL ES 2.0 so am very likely missing something, but under what circumstances could point sprites be used effectively in a game (apart from the obvious being a particle system)? If they can't go over a certain size, then aren't they pretty much useless for characters etc? (I understand also that the min and max sizes may vary from device to device making things even more unpredictable)?

EDIT: Further to the comments below and further research it appears that the only size that is guaranteed for a 'Point' is '1' (being 1 pixel).

So on a system like Android with so many screen DPI's and resolutions, are points even realistically usable for particle systems?

Let me elaborate, on a low Res / DPI screen a single pixel point will appear quite large , but on say, a Nexus 10 tablet with it's really high Res / DPI screen a single pixel point is going to virtually unnoticeable. Normally when I work with sprites I scale them according to the screen resolution (ie, if I want a sprite to take up 1/4 of the available screen I will simply scale it by screen/2 in both X and Y directions. This gives me screen independence and works great. But if I need a particle size of say 4 on my N10 Tablet so it takes up the same amount of relative space than of say a lower-end (and lower res) phone device which only uses a point size of 1 and I can't be guarantee anything bigger than 1 pixel - how is this going to work?

I'm just trying to understand when Points/Point Sprites would be useful in a system like Android!?

Zippy
  • 3,826
  • 5
  • 43
  • 96
  • In many cases it may be easier to use textured quads instead of point sprites. This comes from the fact that point sprite size is given as pixels and at least the cases I've dealt with required proportional sizes. As for speed comparisons I've never noticed much difference between point sprites and quads. – harism Mar 24 '13 at 12:46
  • Thanks @harism, this is pretty much what I was thinking, I can't really think of a situation where Points would be more useful than Quads, also am I correct in saying that Points have a limit to their minimum and maximum sizes? – Zippy Mar 24 '13 at 12:57
  • As far as I know there is maximum size for point sprite sizes yes. About minimum I'm not exactly sure unless there's a limitation that makes them at least one pixel sized. – harism Mar 24 '13 at 12:59
  • Awesome - thanks @harism, I've edited my question if you'd care to comment on the edit :-) – Zippy Mar 24 '13 at 13:28
  • I too wondering about the using points sprites and low/high resolution screens. Did you happen to get any clarity ? – kiranpradeep Feb 22 '15 at 04:53

0 Answers0