farm_ground

The whole 2 km farm read as one surface. Samples the crop-state texture the farmland slice keeps in step with Farm.strip() — R = how much crop is standing, G = which crop (0 track/verge, 0.5 wheat, 1 maize), B = a per-plot seed — and paints wheat and maize with their own row directions and colours, pale cut stubble where the swarm has eaten, dirt tracks with wheel ruts in the gaps between plots, grassy verges along the plot edges, and dry scrub beyond the farm boundary. Exposes surface() so the engine's own low-sun lighting and shadows land on it.