By: VertexMaster (nope.delete@this.nope.com), August 4, 2016 4:38 pm
Room: Moderated Discussions
> What do you mean by "stepping over scan lines"?
> Scanline as 1 pixel line?
I should have just said "stepping over pixels". Historically tile-rendering is clipping triangles to a tile, rendering the complete tile etc. However I have no idea how GCN renders blocks ("tiles"), so I just meant for all we know, they step thru (scanning) every triangle intersecting the block and just skips pixels outside of the block. Not suggesting they do, but my point is that what appears in the frame buffer doesn't tell us much about how the rasterization process works.
> In 21 century GPUs always render tiles. Also depth buffer tiles on GCN are already compressed.
Um, the TeraScale (VLIW) card Kanter tested appeared to be doing scanline rendering (more or less) and it's not that old (2009), so that's decidedly "21st century". I imagine the Cayman (V series (6000) was the same (2010). And yes, the z-buffer compression started back in the 90s with the Radeon 256 (7000 series), although I don't know if it was block-level ("tiling") until "Hyper-Z", or they were just handling clear-all cases like zero/one.
> Scanline as 1 pixel line?
I should have just said "stepping over pixels". Historically tile-rendering is clipping triangles to a tile, rendering the complete tile etc. However I have no idea how GCN renders blocks ("tiles"), so I just meant for all we know, they step thru (scanning) every triangle intersecting the block and just skips pixels outside of the block. Not suggesting they do, but my point is that what appears in the frame buffer doesn't tell us much about how the rasterization process works.
> In 21 century GPUs always render tiles. Also depth buffer tiles on GCN are already compressed.
Um, the TeraScale (VLIW) card Kanter tested appeared to be doing scanline rendering (more or less) and it's not that old (2009), so that's decidedly "21st century". I imagine the Cayman (V series (6000) was the same (2010). And yes, the z-buffer compression started back in the 90s with the Radeon 256 (7000 series), although I don't know if it was block-level ("tiling") until "Hyper-Z", or they were just handling clear-all cases like zero/one.