DrawTerrain is a geometry node system that generates 3D landscapes based on curve brush strokes. It allows users to quickly sketch out terrain compositions and update them in real time. An adaptive subdivision feature optimizes memory usage by adding geometry only where it is needed, such as mountain peaks and detailed silhouettes. The system includes a custom shader node group that blends up to five material layers, incorporating data maps for height, erosion, flow, and soil alongside custom PBR textures. Users can stack multiple modifiers to carve paths, or layer overlapping planes with varying levels of subdivision to build complex environments featuring sedimentation, sand, or snow. Terrains generated by the tool can also be exported as heightmaps for further refinement in external landscape software like Gaea.