diff --git a/tools/editor/terrain_editor.cpp b/tools/editor/terrain_editor.cpp
index a5f57fcd..2a684807 100644
--- a/tools/editor/terrain_editor.cpp
+++ b/tools/editor/terrain_editor.cpp
@@ -826,6 +826,9 @@ void TerrainEditor::carveRiver(const glm::vec3& start, const glm::vec3& end,
 
 void TerrainEditor::createCrater(const glm::vec3& center, float radius, float depth, float rimHeight) {
     if (!terrain_) return;
+    if (!std::isfinite(center.x) || !std::isfinite(center.y) ||
+        !std::isfinite(radius) || radius <= 0.0f ||
+        !std::isfinite(depth) || !std::isfinite(rimHeight)) return;
     recordGeneratorUndo();
 
     for (int ci = 0; ci < 256; ci++) {
@@ -869,6 +872,9 @@ void TerrainEditor::createCrater(const glm::vec3& center, float radius, float de
 
 void TerrainEditor::createMesa(const glm::vec3& center, float radius, float height, float edgeSteepness) {
     if (!terrain_) return;
+    if (!std::isfinite(center.x) || !std::isfinite(center.y) ||
+        !std::isfinite(radius) || radius <= 0.0f ||
+        !std::isfinite(height) || !std::isfinite(edgeSteepness)) return;
     recordGeneratorUndo();
     for (int ci = 0; ci < 256; ci++) {
         auto& chunk = terrain_->chunks[ci];