Commit graph

11 commits

Author SHA1 Message Date
Elias Naur 6a4e26ef2a all: add optional memory checks
Defining MEM_DEBUG in mem.h will add a size field to Alloc and enable
bounds and alignment checks for every memory read and write.

Notes:
- Deriving an Alloc from Path.tiles is unsound, but it's more trouble to
  convert Path.tiles from TileRef to a variable sized Alloc.
- elements.comp note that "We should be able to use an array of structs but the
  NV shader compiler doesn't seem to like it". If that's still relevant, does
  the shared arrays of Allocs work?

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2021-02-15 16:07:45 +01:00
Elias Naur 4de67d9081 unify GPU memory management
Merge all static and dynamic buffers to just one, "memory". Add a malloc
function for dynamic allocations.

Unify static allocation offsets into a "config" buffer containing scene setup
(number of paths, number of path segments), as well as the memory offsets of
the static allocations.

Finally, set an overflow flag when an allocation fail, and make sure to exit
shader execution as soon as that triggers. Add checks before beginning
execution in case the client wants to run two or more shaders before checking
the flag.

The "state" buffer is left alone because it needs zero'ing and because it is
accessed with the "volatile" keyword.

Fixes #40

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-12-27 20:24:29 +01:00
Elias Naur d21f2b68de all: add SPDX license headers
Fixes #53

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-12-11 18:24:35 +01:00
Elias Naur feeb459fa1 remove FillMask and FillMaskInv
Obsoleted by BeginClip/EndClip.

Updates #36

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-11-29 16:59:58 +01:00
Raph Levien d14895b107 Continuing work on clips
I realized there's a problem with encoding clip bboxes relative to the
current transform (see #36 for a more detailed explanation), so this is
changing it to absolute bboxes.

This more or less gets clips working. There are optimization
opportunities (all-clear and all-opaque mask tiles), and it doesn't deal
with overflow of the blend stack, but it seems to basically work.
2020-11-20 18:25:27 -08:00
Raph Levien f53d00e6bc Add transforms and state stack
Actually handle transforms in RenderCtx (was implemented in renderer but
not actually plumbed through). This also requires maintaining a state
stack, which will also be required for clipping.

This PR also starts work on encoding clipping, including tracking
bounding boxes.

WIP, none of this is tested yet.
2020-11-20 18:25:27 -08:00
Elias Naur 8fab45544e shader: implement clip paths
Expand the the final kernel4 stage to maintain a per-pixel mask.

Introduce two new path elements, FillMask and FillMaskInv, to fill
the mask. FillMask acts like Fill, while FillMaskInv fills the area
outside the path.

SVG clipPaths is then representable by a FillMaskInv(0.0) for every nested
path, preceded by a FillMask(1.0) to clear the mask.

The bounding box for FillMaskInv elements is the entire screen; tightening of
the bounding box is left for future work. Note that a fullscreen bounding
box is not hopelessly inefficient because completely filling a tile with
a mask is just a single CmdSolidMask per tile.

Fixes #30

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-10-09 13:20:26 +02:00
Elias Naur dceb0f9412 piet-gpu-types: remove unused annotated types
Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-09-21 10:55:58 +02:00
Raph Levien 294f6fd1db Experiment with new sorting scheme
Path segments are unsorted, but other elements are using the same
sort-middle approach as before.

This is a checkpoint. At this point, there are unoptimized versions
of tile init and coarse path raster, but it isn't wired up into a
working pipeline. Also observing about a 3x performance regression in
element processing, which needs to be investigated.
2020-06-03 09:29:25 -07:00
Raph Levien 076e6d600d Progress on wiring up fills
Write the right_edge to the binning output.

More work on encoding the fill/stroke distinction and plumbing that
through the pipeline. This is a bit unsatisfying because of the code
duplication; having an extra fill/stroke bool might be better, but I
want to avoid making the structs bigger (this could be solved by
better packing in the struct encoding).

Fills are plumbed through to the last stage. Backdrop is WIP.
2020-05-20 11:14:19 -07:00
Raph Levien 736f883f66 Store annotated elements
Apply transform to paths and annotate with computed linewidth and
bounding box information, storing the result.
2020-05-12 12:13:39 -07:00