Question by brandon1 · Feb 16, 2011 at 05:13 PM · ios particles alpha blending overdraw

Large particle overdraw on IOS

Ok, so I get that doing alpha blended particles that cover 30% of the screen is bad in general because of the overdraw, but my instance seems to not make sense.

here is my instance

iPad using iOS 4.2 sdk, targeted 3.0

One plane with a single shader and a 1024x1024 PVRTC 2 bit texture

10 alpha blended particles with a constant force (covers 30% of the screen)

20% of the frame covered by kinematic rigidbody planes (12 total)

Framerate at 20 with particles
Framerate at 300 without particles

The game's graphics are very simple or I wouldn't think of doing such large particles. Profiling has pointed me towards overdraw. WHYYYY does it lag so much, I can understand the framerate dropping even by half, but I've never seen 30% overdraw kill the FPS so badly. Any suggestions?

Notes:

There are no issues with it running in the editor
I tested running 3000 particles using the same material at 1/15th the size, got a framerate of 40

Add comment · Show 1

Eric5h5 · Feb 16, 2011 at 08:23 PM 0

Well, naturally there aren't any issues in the editor, because the graphics card you have in your computer is probably 100X more powerful. I think you answered your own question though: avoid overdraw where possible. Also you could try more optimized shaders, such as the new ones in Unity 3.2.

Welcome to Unity Answers

If you’re new to Unity Answers, please check our User Guide to help you navigate through our website and refer to our FAQ for more information.

Before posting, make sure to check out our Knowledge Base for commonly asked Unity questions.

Check our Moderator Guidelines if you’re a new moderator and want to work together in an effort to improve Unity Answers and support our users.

Large particle overdraw on IOS

0 Replies

Your answer

Welcome to Unity Answers

Follow this Question

Related Questions