Polygon and mask previously pushed null texture handles ('fake'
implementations). They now generate real ShaderJobPayloads and render
through the existing GPU shader pipeline:
- shaderfx: std140 uniform array support (Vec4Array(N)) — the parser
accepts 'uniform <type> <name>[N];' declarations, translate()
re-emits them as vec4[N] block members with per-element std140
offsets, and pack_uniforms writes array items from the new
NodeValue::Vec4Array value, padding short arrays to the declared N.
- polygon: value() collects the inherited points array (row element
keys 'points_in[i]', else the node's own per-element values — an
unconnected array resolves to the default pentagon via
GetValueAtTime parity) and pushes a ShaderJobPayload; the 'rgb'
fragment shader rasterizes the closed point loop with an odd-even
fill in screen space (center-translated, y-flipped to match the C++
point convention) and outputs color_in inside / transparent outside.
The CPU QPainterPath generate_frame stays a documented no-op.
- mask: value() pushes a single ShaderJobPayload whose new 'mask'
fragment shader folds the whole C++ chain into one GPU pass — base
texture multiplied by the polygon matte, optional invert, and the
optional feather gaussian softens the matte during sampling (the
separable blur.frag h/v iterations as a one-pass product,
density-normalized, radius capped at 16 px).
- Tests: translate/pack array coverage in shaderfx, GPU end-to-end
rasterization of the pentagon (center white, corner transparent),
mask multiply/invert/feather on real frames, and updated oak-node
payload assertions. oak-render 178, oak-node 440, oak-app 272 lib
tests pass.