Flat terrain develops dark lines along adjacent triangle edges. This is visible without original textures, sprites or shadows. On a public 32 by 32 grass world, the production renderer returns 101,136,75,255 at an interior shared edge instead of the uniform grass color 111,148,82,255.
The current chunk painter fills separate antialiased triangles over transparency. A private one-variable compositing experiment fills this pixel correctly, supporting a coverage problem. Additive compositing alone is not a qualified solution because mixed materials and overlapping elevated geometry need correct ownership and draw order.
The supplied reference draws a shared triangle mesh in Background.java. Preserve its geometry and triangle ordering while repairing the browser raster path.
Acceptance:
- Retain the real browser regression with an empty authored atlas and unchanged public simulation.
- Eliminate interior coverage cracks across flat terrain, chunk boundaries and camera movement.
- Verify mixed materials, elevations, overlaps, fog and shading without expanding triangles, painting filler lines or adjusting source colors to hide gaps.
- Keep original source pixels unchanged and bound raster/cache resources.
- Verify actual browser output, simulation checksums, complete checks and CI.
Source owner: game renderer. Related #20 and #88. The reproduction is engineering evidence, not an observation of the original Gold executable. Original media remains under the existing publication policy.