using System;
using UnityEngine;
using UnityEngine.TerrainTools;

namespace UnityEditor.TerrainTools
{
    /// <summary>
    /// An interface that allows rendering of terrain-brushes for both preview purposes and to modify the terrain.
    /// NOTE: This uses the GPU so material properties will also need to be dealt with prior to rendering.
    /// </summary>
    public interface IPaintContextRender : IDisposable
    {
        /// <summary>
        /// Sets up the material properties required when rendering a terrain-brush.
        /// </summary>
        /// <param name="paintContext">The paint-context to use.</param>
        /// <param name="brushTransform">The brush-transform to be rendered.</param>
        /// <param name="material">The material whose properties are to be initialised.</param>
        void SetupTerrainToolMaterialProperties(PaintContext paintContext, BrushTransform brushTransform, Material material);

        /// <summary>
        /// Renders the terrain-brush using the specified material/pass to the paint-context provided.
        /// </summary>
        /// <param name="paintContext">The paint-context to modify.</param>
        /// <param name="material">The material to use when rendering to the terrain.</param>
        /// <param name="pass">The pass on the material to use.</param>
        void RenderBrush(PaintContext paintContext, Material material, int pass);
    }

    /// <summary>
    /// An interface that represents the method for rendering the terrain-brush preview.
    /// </summary>
    public interface IPaintContextRenderPreview : IPaintContextRender
    {
        /// <summary>
        /// Renders a preview of the terrain-brush using the specified material/pass and paint-context provided.
        /// </summary>
        /// <param name="paintContext">The paint-context to preview the changes against.</param>
        /// <param name="previewTexture">The type of texture to preview.</param>
        /// <param name="brushTransform">The brush-transform to be rendered.</param>
        /// <param name="material">The material to use when rendering to the terrain.</param>
        /// <param name="pass">The pass on the material to use.</param>
        void RenderBrushPreview(PaintContext paintContext, TerrainBrushPreviewMode previewTexture, BrushTransform brushTransform, Material material, int pass);
    }
}