Instead of gradually smoothing or flattening terrain based on the selected brush strength, the tools can make very aggressive changes to the terrain. Smooth frequently removes a substantial amount of terrain in a single pass, creating deep cuts or holes instead of smoothing the existing surface. Flatten can similarly produce abrupt, jagged changes rather than a predictable, gradual adjustment. The affected terrain contains no gaps, holes, or malformed regions prior to editing. It is a clean terrain import generated using professional landscape-authoring tools. Isolated testing on small terrain patches does not reproduce the issue, whereas three additional users with systems ranging from low-end to high-end have independently observed the same behaviour when editing large terrain maps.
System information:
Processor: AMD Ryzen 7 8845HS with Radeon 780M Graphics, 3.80 GHz
Memory: 16 GB RAM
Dedicated GPU: NVIDIA GeForce RTX 4070 Laptop GPU, 8 GB
Integrated GPU: AMD Radeon 780M Graphics
Storage: approximately 1.35 TB used of 1.84 TB
Expected behavior
Smooth should gradually average and soften the existing terrain surface while preserving its overall shape and volume. Brush strength should control how quickly this smoothing occurs, allowing repeated passes to produce progressively smoother results rather than removing large amounts of terrain at once. Flatten should move terrain toward the selected elevation in a controlled and predictable manner, with smooth transitions around the affected area rather than abrupt cuts, stepped surfaces, or jagged edges. On large terrain maps, these tools should behave consistently with those on smaller maps, as long as Studio is otherwise running normally. The amount of terrain present should not significantly affect the brush’s effective strength or destructive behaviour.
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