UIAtlas generates an antialiased white corner for each radius in
ROUND_RECT_RADII (8, 16, 24, 32 UI units) and each style (filled, and
thin/medium/thick outlines from ROUND_RECT_THICKNESS) at the atlas DPI.
DrawBuffer::DrawRoundRect mirrors the corner into all four corners and
stretches the corner's last texel row/column along the edges, so a
round rect is 9 quads (8 for outlines).
Other radii use the nearest corner, scaled. The LogoScreen temporarily
draws some for testing.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
These own GPU objects, memory or refcounts in their destructors (or assert
there that they were torn down), so a copy would double-free. Nothing copies
them today; this keeps it that way. The manager base classes cover every
backend's subclass.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
