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Source/Editor/Tools/Terrain/Sculpt/SculptMode.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using FlaxEngine;
+
+namespace FlaxEditor.Tools.Terrain.Sculpt
+{
+    /// <summary>
+    /// Sculpt tool mode. Edits terrain heightmap by moving area affected by brush up or down.
+    /// </summary>
+    /// <seealso cref="FlaxEditor.Tools.Terrain.Sculpt.Mode" />
+    [HideInEditor]
+    public sealed class SculptMode : Mode
+    {
+        /// <inheritdoc />
+        public override bool SupportsNegativeApply => true;
+
+        /// <inheritdoc />
+        public override unsafe void Apply(ref ApplyParams p)
+        {
+            var strength = p.Strength * 1000.0f;
+            var brushPosition = p.Gizmo.CursorPosition;
+
+            // Apply brush modification
+            Profiler.BeginEvent("Apply Brush");
+            for (int z = 0; z < p.ModifiedSize.Y; z++)
+            {
+                var zz = z + p.ModifiedOffset.Y;
+                for (int x = 0; x < p.ModifiedSize.X; x++)
+                {
+                    var xx = x + p.ModifiedOffset.X;
+                    var sourceHeight = p.SourceHeightMap[zz * p.HeightmapSize + xx];
+
+                    var samplePositionLocal = p.PatchPositionLocal + new Vector3(xx * FlaxEngine.Terrain.UnitsPerVertex, sourceHeight, zz * FlaxEngine.Terrain.UnitsPerVertex);
+                    Vector3.Transform(ref samplePositionLocal, ref p.TerrainWorld, out Vector3 samplePositionWorld);
+
+                    var paintAmount = p.Brush.Sample(ref brushPosition, ref samplePositionWorld);
+
+                    p.TempBuffer[z * p.ModifiedSize.X + x] = sourceHeight + paintAmount * strength;
+                }
+            }
+            Profiler.EndEvent();
+
+            // Update terrain patch
+            TerrainTools.ModifyHeightMap(p.Terrain, ref p.PatchCoord, p.TempBuffer, ref p.ModifiedOffset, ref p.ModifiedSize);
+        }
+    }
+}