Do VBOs do anything on a device with unified memory? There is no separate graphics memory on many of these devices, right?
On Jun 20, 9:51 pm, Robert Green <rbgrn....@gmail.com> wrote: > Navigateur, > > Performance is highly device-dependent. If you're not seeing any > performance differences, it would be helpful if you listed on which > device, what your FPS is with/without VBOs, etc.. > > It sounds like you're doing it right. I doubt it matters how you > partition the vertex attributes. You can do what you do or do what I > do which is have 3 separate VBOs for them. I would expect no > difference there. If you're not getting a performance improvement > then that's not a bottleneck for your app/game, but it's still > lightening the load on the bus so is a good thing overall. Most games > are fill-bound, not vert-bound. > > On Jun 20, 11:46 am, Navigateur <naveen.c...@googlemail.com> wrote: > > > What is your approximate experimental fps improvement using exactly > > the same content with and without VBOs? I'm testing with 3000 static > > verts (GL_STATIC_DRAW) and I'm getting exactly the same frame rate > > with and without VBOs, only the set-up time is longer with VBOs. What > > are your results with and without? If you're sure there's an > > improvement, then what might I be doing wrong with my VBOs? (I'm using > > 2 VBOs, one for the indices and the other for verts, normals and > > texturecoords) And what's your way of doing it? > > > On Jun 20, 11:50 am, Robert Green <rbgrn....@gmail.com> wrote: > > > > The question "are VBOs faster" is a very subjective one. > > > > I can answer the question "are VBOs faster for large amounts of static > > > geometry" and the answer in my experience has been "yes, very much so, > > > especially on first-gen devices." > > > > For quads and such? No. In fact, it could actually be slower > > > depending on the chip and implementation. > > > > VBOs are designed to reduce bus bandwidth usage for static geometry. > > > If you're not pushing too much across that bus (as in the case of > > > quads or very few, very low poly objects), they won't do much. If, on > > > the other hand, you're actually running static scenes that are moving > > > 5k polys per draw eg (7.5k verts, 7.5k normals, 15k indices, 7.5k UVs) > > > = 270Kb, you will most likely see some sort of improvement, especially > > > on chips like the qualcomms as they have fairly slow transfers. Just > > > think, 270Kb @30fps = 8.1Mb of memory copying per second you're saving > > > using VBOs. > > > > If you're rendering scenes that have REALLY large amounts of geometry > > > (for mobile), such as 50k or 100k polys, you'll find that you'll be > > > totally vert-bound on the first gen devices, so there's kind of that > > > limit there as to how effective VBOs can be. The spots where they > > > REALLY shine, like really high poly counts, can't ever be used on the > > > first-gen phones because they are incapable of processing that many > > > vertices with high efficiency anyway. High end devices running big > > > scenes like that will really benefit from them because it's a whole > > > lot of memory transfer savings. Anyone doing things like that will > > > want to be using configurable LoD to support the first-gens while > > > keeping things high quality on newer chips. > > > > I would be interested in a simple test that increases poly count frame > > > by frame and graphs the FPS up from 0 to 100k polys. Running one pass > > > textured and the other just colored would be a good way to > > > discriminate between becoming fill-bound and memory or vert-bound. > > > Seeing this data on an MSM7200, Cortex/PVR (Droid) and a snapdragon > > > would be very useful for determining optimization targets. > > > > On Jun 20, 4:37 am, Navigateur <naveen.c...@googlemail.com> wrote: > > > > > No I'm not even using draw_texture. I'm comparing using VBOs to just > > > > ordinary Buffers for the vertices (and no draw_texture). My test is > > > > not near the max frame rate for my device. > > > > > On Jun 20, 12:21 am, Miguel Morales <therevolti...@gmail.com> wrote: > > > > > > Well, if you look at the talk google gave the developer gave a short > > > > > note about > > > > > it:http://code.google.com/intl/es-ES/events/io/2010/sessions/writing-rea... > > > > > If memory serves me correct, you won't gain much of a speed gain from > > > > > using VBOs as opposed to say draw_texture. > > > > > This is because the FPS is capped at 30FPS for some devices, however I > > > > > can't recall the details. > > > > > > Miguel. > > > > > > On Sat, Jun 19, 2010 at 3:01 PM, Navigateur > > > > > <naveen.c...@googlemail.com> wrote: > > > > > > I've been trying VBOs (3D) and I've seen no improvement at all on my > > > > > > Motorola Dext over not using VBOs. > > > > > > > I've tried all kinds of configurations, interleaved arrays, > > > > > > bytebuffers instead of floatbuffers, both direct and indirect. > > > > > > > My question is, has anybody got any measured improvement in frames > > > > > > per > > > > > > second by using VBOs instead of exactly the same content without > > > > > > VBOs? > > > > > > > If and only if so, what were your fps results? And can you therefore > > > > > > show me the "proper" way of doing VBOs instead of not? > > > > > > Has anybody else got exactly the same fps with and without VBOs? > > > > > > > -- > > > > > > You received this message because you are subscribed to the Google > > > > > > Groups "Android Developers" group. > > > > > > To post to this group, send email to > > > > > > android-developers@googlegroups.com > > > > > > To unsubscribe from this group, send email to > > > > > > android-developers+unsubscr...@googlegroups.com > > > > > > For more options, visit this group at > > > > > >http://groups.google.com/group/android-developers?hl=en > > > > > > --http://diastrofunk.com,http://developingthedream.blogspot.com/,http:/..., > > > > > ~Isaiah 55:8-9- Hide quoted text - > > > > > > - Show quoted text -- Hide quoted text - > > > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "Android Developers" group. 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