no, not at all, the 10mb Edram handles the AA , not the xenos which essentiall gives the 360 up to 4xMsaa with no cost to system memory, everything done on the cell or the RSX costs system memory, and the Edrams system bandwith is 100x faster than the Ps3's system bandwith (256gb/sec vs 25gb/per sec) you also have to take into account that the xenos can run various DX10 subroutines, which niether the cell or RSX can , you also have to take into account the unified shader architecture which effectively lowers the system memory cost of shader operations add to that the fact the 360 has 18mb more useable memory, dude, it's not a good thing that the RSX needs to use the CELL as a zimmer frame to match the xenos performance because that takes up vital CPU recources thet are used to run non graphics aspects of the game, and the 360's CPU can handle AA as well, AAA (analytical anti aliasing) is CPU based AA solution that emeulates 8xmsaa and has already been used in the 360 version of metro 2033, the Xenos has a huge advantage over the RSX in system memory savings, like i stated before, the ps3 edges the 360 out in power, but the xenos is a better GPU than the RSX period.delta3074
Is not free it has been discus on beyond 3D to hell and back.
In terms of computational resources, Xenos' AA really is absolutely and honestly free.
Per "pixel", Xenos computes one color, a depth gradient and determines a subpixel coverage mask. The maks is just four bits. The depth gradient is sufficient because all potentially covered subpixels, while they have variable depth values, are from the same triangle. Hence this connection doesn't need much bandwidth (actually less bandwidth than an equivalent PC part's road to memory because blending is also "free", even without any AA).
Inside the daughter die, the color and z values are replicated to all covered samples according to the mask bits, z test is done and blending is done. So in the worst case, for one incoming pixel the daughter die needs to read/modify/write four subpixel depth values (for a subpixel-precise depth test) and read/modify/write four subpixels' colors (for blending). The eDRAM daughter die has very high internal bandwidth and can cope with this all just fine, and this is exactly the reason why this is deemed "free".
The catch:
The eDRAM daughter die, while having that very high bandwidth, only has limited storage space. Rendering in high resolutions with AA will exhaust this space. Doing 4xMSAA requires four times as much space to be set aside than rendering without AA. If you don't have that space, you can't hold the whole backbuffer at once.
The proposed solution is to split the scene up into tiles that do fit the eDRAM space limits.
E.g. instead of rendering a complete 1280x720 w 4xMSAA frame (which you can't), the rendering process can be split up into three 1280x240 partitions (roughly ~9,8MB each) which are rendered sequentially. You flush out the finished partitions to system memory to make room for the next one. If you have all three partitions down in system memory the frame is done, you can point the RAMDAC there to scan it out and start building up the next frame in the same way.
But this is not free.
http://forum.beyond3d.com/showthread.php?t=40456
http://forum.beyond3d.com/showthread.php?t=29856
Here another thread where AA is discus,is not actually free but more like low costing that it would be without it.
With that bandwidth you just post you are not telling the whole picture,and i show you how this is not apple to apple again for the last time,the RSX has 22.GB bandwidth Cell has a 25.6 bandwidht,is not just 25GB like you claim,also notice the 20 GB connection that go's from the RSX to Cell,and the 15 GB one that go's from Cell to the RSX,on 360 you will not find that one,becuase the Xenon and Xenos don't work like Cell and the RSX.
18MB more of usable memory won mean much dude it would not,the Satur had double the video ram of the PS1,and the PS1 could run 3D games better than the Saturn,it was slower on 2D games but on 3D games no chance,also look at what sony did with the PS2 and 32 MB of ram,sony developer are use to work with console with low ram,in this case is not low is almost the same.
Cell is a monster because not only help the RSX,but also maintain a nice work flow on the CPU task it most handle unlike what you claim,by the way the xbox 360 3 core CPU has just 1 MB of cache which is incredibly low,considering a dual core pentium 4 of that time had 2 MB 1 per core,and compare to Cell which has 256 KB for each SPU without even counting the core chache of 512 KB,xbox 360 CPU has to spread 1 MB between 6 threads dude.
In the end this argument is pointless what to believe the xbox 360 is more powerful ok,i admit it the xbox 360 is more powerful,now wake me up when teh xbox 360 games surpase Unccharted 2 at least.
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