Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/third_party/rust/wpf-gpu-raster/README.md b/third_party/rust/wpf-gpu-raster/README.md
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+This is a port of the WPF hardware rasterizer code to Rust. That
+rasterizer is predecessor to the Direct2D rasterizer. Direct2D still
+uses a similar technique when run on hardware that does not support
+Target Independent Rasterization.
+
+Design
+======
+
+The general algorithm used for rasterization is a vertical sweep of
+the shape that maintains an active edge list.  The sweep is done
+at a sub-scanline resolution and results in either:
+   1. Sub-scanlines being combined in the coverage buffer and output
+      as "complex scans". These are emitted as lines constructed out
+      of triangle strips.
+   2. Simple trapezoids being recognized in the active edge list
+      and output using a faster simple trapezoid path.
+
+Bezier flattening is done using an approach that uses forward differencing
+of the error metric to compute a flattened version that would match a traditional
+adaptive recursive flattening.
+
+