TerrainPaintToolWithOverlays<T0>

Description

Base class for Terrain painting tools, which inherit from Editor Tools.

Derive from this class to implement your own terrain painting tools, which also appear in the Terrain Tools overlay.

using UnityEngine;
using UnityEditor;
using UnityEditor.TerrainTools;

class CustomTerrainToolWithOverlays : TerrainPaintToolWithOverlays<CustomTerrainToolWithOverlays>
{
    private float m_BrushRotation;
    
    // Return true for this property to show the brush selector overlay
    public override bool HasBrushMask => true;

    // Return true for this property to show the tool settings overlay
    public override bool HasToolSettings => true;
    
    // Return true for this property to display the brush attributes overlay
    public override bool HasBrushAttributes => true;
    
    // File names of the light theme icons - prepending d_ to the file name generates dark theme variants.
    // public override string OnIcon => "Assets/Icon_on.png";
    // public override string OffIcon => "Assets/Icon_off.png";

    // The toolbar category the icon appears under
     public override TerrainCategory Category => TerrainCategory.CustomBrushes;

    // Where in the icon list the icon appears
    public override int IconIndex => 100;
    
    // Name of the Terrain Tool. This appears in the tool UI
    public override string GetName()
    {
        return "Examples/Basic Custom Terrain Tool";
    }

    // Description for the Terrain Tool. This appears in the tool UI
    public override string GetDescription()
    {
        return "This Terrain Tool shows how to add custom UI to a tool and paint height.";
    }

    // Override this function to add UI elements to the inspector
    public override void OnInspectorGUI(Terrain terrain, IOnInspectorGUI editContext)
    {
        EditorGUILayout.HelpBox("In Terrain Inspector", MessageType.None); 
        editContext.ShowBrushesGUI(5, BrushGUIEditFlags.All);
        m_BrushRotation = EditorGUILayout.Slider("Rotation", m_BrushRotation, 0, 360);
    }

    // Override this function to add UI elements to the tool settings overlay 
    public override void OnToolSettingsGUI(Terrain terrain, IOnInspectorGUI editContext)
    {
        EditorGUILayout.HelpBox("In Overlays", MessageType.None); 
        m_BrushRotation = EditorGUILayout.Slider("Rotation", m_BrushRotation, 0, 360);
    }

    // Ease of use function for rendering modified Terrain Texture data into a PaintContext. Both OnRenderBrushPreview and OnPaint use this.
    private void RenderIntoPaintContext(UnityEngine.TerrainTools.PaintContext paintContext, Texture brushTexture, float brushOpacity, UnityEngine.TerrainTools.BrushTransform brushXform)
    {
        // Get the built-in painting Material reference
        Material mat = UnityEngine.TerrainTools.TerrainPaintUtility.GetBuiltinPaintMaterial();
        // Bind the current brush texture
        mat.SetTexture("_BrushTex", brushTexture);
        // Bind the tool-specific shader properties
        var opacity = Event.current.control ? -brushOpacity : brushOpacity;
        mat.SetVector("_BrushParams", new Vector4(opacity, 0.0f, 0.0f, 0.0f));
        // Set up the material for reading from/writing into the PaintContext texture data. This step is necessary to set up the correct shader properties for appropriately transforming UVs and sampling textures within the shader
        UnityEngine.TerrainTools.TerrainPaintUtility.SetupTerrainToolMaterialProperties(paintContext, brushXform, mat);
        // Render into the PaintContext's destinationRenderTexture using the built-in painting Material. The ID for the Raise/Lower pass is 0
        Graphics.Blit(paintContext.sourceRenderTexture, paintContext.destinationRenderTexture, mat, 0);
    }
    
    // Render Tool previews in the Scene view
    public override void OnRenderBrushPreview(Terrain terrain, IOnSceneGUI editContext)
    {
        // Don't render preview if this isn't a Repaint
        if (Event.current.type != EventType.Repaint) return;

        // Only do the rest if user mouse hits valid terrain
        if (!editContext.hitValidTerrain) return;

        // Get the current BrushTransform under the mouse position relative to the Terrain
        UnityEngine.TerrainTools.BrushTransform brushXform = UnityEngine.TerrainTools.TerrainPaintUtility.CalculateBrushTransform(terrain, editContext.raycastHit.textureCoord, editContext.brushSize, m_BrushRotation);
        // Get the PaintContext for the current BrushTransform. This has a sourceRenderTexture from which to read existing Terrain texture data.
        UnityEngine.TerrainTools.PaintContext paintContext = UnityEngine.TerrainTools.TerrainPaintUtility.BeginPaintHeightmap(terrain, brushXform.GetBrushXYBounds(), 1);
        // Get the built-in Material for rendering Brush Previews
        Material previewMaterial = TerrainPaintUtilityEditor.GetDefaultBrushPreviewMaterial();
        // Render the brush preview for the sourceRenderTexture. This shows up as a projected brush mesh rendered on top of the Terrain
        TerrainPaintUtilityEditor.DrawBrushPreview(paintContext, TerrainBrushPreviewMode.SourceRenderTexture, editContext.brushTexture, brushXform, previewMaterial, 0);
        // Render changes into the PaintContext destinationRenderTexture
        RenderIntoPaintContext(paintContext, editContext.brushTexture, editContext.brushStrength, brushXform);
        // Restore old render target
        RenderTexture.active = paintContext.oldRenderTexture;
        // Bind the sourceRenderTexture to the preview Material. This is used to compute deltas in height
        previewMaterial.SetTexture("_HeightmapOrig", paintContext.sourceRenderTexture);
        // Render a procedural mesh displaying the delta/displacement in height from the source Terrain texture data. When you modify Terrain height, this shows how much the next paint operation alters the Terrain height
        TerrainPaintUtilityEditor.DrawBrushPreview(paintContext, TerrainBrushPreviewMode.DestinationRenderTexture, editContext.brushTexture, brushXform, previewMaterial, 1);
        // Cleanup resources
        UnityEngine.TerrainTools.TerrainPaintUtility.ReleaseContextResources(paintContext);
    }
    
    // Perform painting operations that modify the Terrain texture data
    public override bool OnPaint(Terrain terrain, IOnPaint editContext)
    {
        // Get the current BrushTransform under the mouse position relative to the Terrain
        UnityEngine.TerrainTools.BrushTransform brushXform = UnityEngine.TerrainTools.TerrainPaintUtility.CalculateBrushTransform(terrain, editContext.uv, editContext.brushSize, m_BrushRotation);
        // Get the PaintContext for the current BrushTransform. This has a sourceRenderTexture from which to read existing Terrain texture data
        // and a destinationRenderTexture into which to write new Terrain texture data
        UnityEngine.TerrainTools.PaintContext paintContext = UnityEngine.TerrainTools.TerrainPaintUtility.BeginPaintHeightmap(terrain, brushXform.GetBrushXYBounds());
        // Call the common rendering function that OnRenderBrushPreview and OnPaint use
        RenderIntoPaintContext(paintContext, editContext.brushTexture, editContext.brushStrength, brushXform);
        // Commit the modified PaintContext with a provided string for tracking Undo operations. This function handles Undo and resource cleanup for you
        UnityEngine.TerrainTools.TerrainPaintUtility.EndPaintHeightmap(paintContext, "Terrain Paint - Raise or Lower Height");

        // Return whether Trees and Details should be hidden while you paint with this Terrain Tool
        return true;
    }
}

Inherited Members