XiuXianGame/Assets/FlatKit/Shaders/Editor/TerrainEditor.cs

using UnityEditor;
using UnityEngine;
using UnityEngine.Experimental.Rendering;
using UnityEngine.Rendering;

namespace FlatKit {
public class TerrainEditor : StylizedSurfaceEditor, ITerrainLayerCustomUI {
    private class StylesLayer
    {
        public readonly GUIContent warningHeightBasedBlending = new GUIContent("Height-based blending is disabled if you have more than four TerrainLayer materials!");

        public readonly GUIContent enableHeightBlend = new GUIContent("Enable Height-based Blend", "Blend terrain layers based on height values.");
        public readonly GUIContent heightTransition = new GUIContent("Height Transition", "Size in world units of the smooth transition between layers.");
        public readonly GUIContent enableInstancedPerPixelNormal = new GUIContent("Enable Per-pixel Normal", "Enable per-pixel normal when the terrain uses instanced rendering.");

        public readonly GUIContent diffuseTexture = new GUIContent("Diffuse");
        public readonly GUIContent colorTint = new GUIContent("Color Tint");
        public readonly GUIContent opacityAsDensity = new GUIContent("Opacity as Density", "Enable Density Blend (if unchecked, opacity is used as Smoothness)");
        public readonly GUIContent normalMapTexture = new GUIContent("Normal Map");
        public readonly GUIContent normalScale = new GUIContent("Normal Scale");
        public readonly GUIContent maskMapTexture = new GUIContent("Mask", "R: Metallic\nG: AO\nB: Height\nA: Smoothness");
        public readonly GUIContent maskMapTextureWithoutHeight = new GUIContent("Mask Map", "R: Metallic\nG: AO\nA: Smoothness");
        public readonly GUIContent channelRemapping = new GUIContent("Channel Remapping");
        public readonly GUIContent defaultValues = new GUIContent("Channel Default Values");
        public readonly GUIContent metallic = new GUIContent("R: Metallic");
        public readonly GUIContent ao = new GUIContent("G: AO");
        public readonly GUIContent height = new GUIContent("B: Height");
        public readonly GUIContent heightParametrization = new GUIContent("Parametrization");
        public readonly GUIContent heightAmplitude = new GUIContent("Amplitude (cm)");
        public readonly GUIContent heightBase = new GUIContent("Base (cm)");
        public readonly GUIContent heightMin = new GUIContent("Min (cm)");
        public readonly GUIContent heightMax = new GUIContent("Max (cm)");
        public readonly GUIContent heightCm = new GUIContent("B: Height (cm)");
        public readonly GUIContent smoothness = new GUIContent("A: Smoothness");
    }

    static StylesLayer s_Styles = null;

    private static StylesLayer styles {
        get {
            if (s_Styles == null) s_Styles = new StylesLayer();
            return s_Styles;
        }
    }

    // Height blend params
    MaterialProperty enableHeightBlend = null;
    const string kEnableHeightBlend = "_EnableHeightBlend";

    MaterialProperty heightTransition = null;
    const string kHeightTransition = "_HeightTransition";

    // Per-pixel Normal (while instancing)
    MaterialProperty enableInstancedPerPixelNormal = null;
    const string kEnableInstancedPerPixelNormal = "_EnableInstancedPerPixelNormal";

    private bool m_ShowChannelRemapping = false;
    enum HeightParametrization
    {
        Amplitude,
        MinMax
    };
    private HeightParametrization m_HeightParametrization = HeightParametrization.Amplitude;

    private static bool DoesTerrainUseMaskMaps(TerrainLayer[] terrainLayers)
    {
        for (int i = 0; i < terrainLayers.Length; ++i)
        {
            if (terrainLayers[i].maskMapTexture != null)
                return true;
        }
        return false;
    }

    protected void FindMaterialProperties(MaterialProperty[] props)
    {
        enableHeightBlend = FindProperty(kEnableHeightBlend, props, false);
        heightTransition = FindProperty(kHeightTransition, props, false);
        enableInstancedPerPixelNormal = FindProperty(kEnableInstancedPerPixelNormal, props, false);
    }

    static public void SetupMaterialKeywords(Material material)
    {
        bool enableHeightBlend = (material.HasProperty(kEnableHeightBlend) && material.GetFloat(kEnableHeightBlend) > 0);
        CoreUtils.SetKeyword(material, "_TERRAIN_BLEND_HEIGHT", enableHeightBlend);

        bool enableInstancedPerPixelNormal = material.GetFloat(kEnableInstancedPerPixelNormal) > 0.0f;
        CoreUtils.SetKeyword(material, "_TERRAIN_INSTANCED_PERPIXEL_NORMAL", enableInstancedPerPixelNormal);
    }

    static public bool TextureHasAlpha(Texture2D inTex)
    {
        if (inTex != null)
        {
            return GraphicsFormatUtility.HasAlphaChannel(GraphicsFormatUtility.GetGraphicsFormat(inTex.format, true));
        }
        return false;
    }

    public override void OnGUI(MaterialEditor materialEditorIn, MaterialProperty[] properties) {
        base.OnGUI(materialEditorIn, properties);
        FindMaterialProperties(properties);

        bool optionsChanged = false;
        EditorGUI.BeginChangeCheck();
        {
            if (enableHeightBlend != null)
            {
                //EditorGUI.indentLevel++;
                materialEditorIn.ShaderProperty(enableHeightBlend, styles.enableHeightBlend);
                if (enableHeightBlend.floatValue > 0)
                {
                    EditorGUI.indentLevel++;
                    EditorGUILayout.HelpBox(styles.warningHeightBasedBlending.text, MessageType.Info);
                    materialEditorIn.ShaderProperty(heightTransition, styles.heightTransition);
                    EditorGUI.indentLevel--;
                }
                //EditorGUI.indentLevel--;
            }

            EditorGUILayout.Space();
        }
        if (EditorGUI.EndChangeCheck())
        {
            optionsChanged = true;
        }

        bool enablePerPixelNormalChanged = false;

        // Since Instanced Per-pixel normal is actually dependent on instancing enabled or not, it is not
        // important to check it in the GUI.  The shader will make sure it is enabled/disabled properly.s
        if (enableInstancedPerPixelNormal != null)
        {
            //EditorGUI.indentLevel++;
            EditorGUI.BeginChangeCheck();
            materialEditorIn.ShaderProperty(enableInstancedPerPixelNormal, styles.enableInstancedPerPixelNormal);
            enablePerPixelNormalChanged = EditorGUI.EndChangeCheck();
            //EditorGUI.indentLevel--;
        }

        if (optionsChanged || enablePerPixelNormalChanged)
        {
            foreach (var obj in materialEditorIn.targets)
            {
                SetupMaterialKeywords((Material)obj);
            }
        }

        // We should always do this call at the end
        materialEditorIn.serializedObject.ApplyModifiedProperties();
    }

    bool ITerrainLayerCustomUI.OnTerrainLayerGUI(TerrainLayer terrainLayer, Terrain terrain)
    {
        var terrainLayers = terrain.terrainData.terrainLayers;

        // Don't use the member field enableHeightBlend as ShaderGUI.OnGUI might not be called if the material UI is folded.
        // heightblend shouldn't be available if we are in multi-pass mode, because it is guaranteed to be broken.
        bool heightBlendAvailable = (terrainLayers.Length <= 4);
        bool heightBlend = heightBlendAvailable && terrain.materialTemplate.HasProperty(kEnableHeightBlend) && (terrain.materialTemplate.GetFloat(kEnableHeightBlend) > 0);

        terrainLayer.diffuseTexture = EditorGUILayout.ObjectField(styles.diffuseTexture, terrainLayer.diffuseTexture, typeof(Texture2D), false) as Texture2D;
        TerrainLayerUtility.ValidateDiffuseTextureUI(terrainLayer.diffuseTexture);

        var diffuseRemapMin = terrainLayer.diffuseRemapMin;
        var diffuseRemapMax = terrainLayer.diffuseRemapMax;
        EditorGUI.BeginChangeCheck();

        bool enableDensity = false;
        if (terrainLayer.diffuseTexture != null)
        {
            var rect = GUILayoutUtility.GetLastRect();
            rect.y += 16 + 4;
            rect.width = EditorGUIUtility.labelWidth + 64;
            rect.height = 16;

            ++EditorGUI.indentLevel;

            var diffuseTint = new Color(diffuseRemapMax.x, diffuseRemapMax.y, diffuseRemapMax.z);
            diffuseTint = EditorGUI.ColorField(rect, styles.colorTint, diffuseTint, true, false, false);
            diffuseRemapMax.x = diffuseTint.r;
            diffuseRemapMax.y = diffuseTint.g;
            diffuseRemapMax.z = diffuseTint.b;
            diffuseRemapMin.x = diffuseRemapMin.y = diffuseRemapMin.z = 0;

            if (!heightBlend)
            {
                rect.y = rect.yMax + 2;
                enableDensity = EditorGUI.Toggle(rect, styles.opacityAsDensity, diffuseRemapMin.w > 0);
            }

            --EditorGUI.indentLevel;
        }
        diffuseRemapMax.w = 1;
        diffuseRemapMin.w = enableDensity ? 1 : 0;

        if (EditorGUI.EndChangeCheck())
        {
            terrainLayer.diffuseRemapMin = diffuseRemapMin;
            terrainLayer.diffuseRemapMax = diffuseRemapMax;
        }

        // Display normal map UI
        terrainLayer.normalMapTexture = EditorGUILayout.ObjectField(styles.normalMapTexture, terrainLayer.normalMapTexture, typeof(Texture2D), false) as Texture2D;
        TerrainLayerUtility.ValidateNormalMapTextureUI(terrainLayer.normalMapTexture, TerrainLayerUtility.CheckNormalMapTextureType(terrainLayer.normalMapTexture));

        if (terrainLayer.normalMapTexture != null)
        {
            var rect = GUILayoutUtility.GetLastRect();
            rect.y += 16 + 4;
            rect.width = EditorGUIUtility.labelWidth + 64;
            rect.height = 16;

            ++EditorGUI.indentLevel;
            terrainLayer.normalScale = EditorGUI.FloatField(rect, styles.normalScale, terrainLayer.normalScale);
            --EditorGUI.indentLevel;
        }

        // Display the mask map UI and the remap controls
        terrainLayer.maskMapTexture = EditorGUILayout.ObjectField(heightBlend ? styles.maskMapTexture : styles.maskMapTextureWithoutHeight, terrainLayer.maskMapTexture, typeof(Texture2D), false) as Texture2D;
        TerrainLayerUtility.ValidateMaskMapTextureUI(terrainLayer.maskMapTexture);

        var maskMapRemapMin = terrainLayer.maskMapRemapMin;
        var maskMapRemapMax = terrainLayer.maskMapRemapMax;
        var smoothness = terrainLayer.smoothness;
        var metallic = terrainLayer.metallic;

        ++EditorGUI.indentLevel;
        EditorGUI.BeginChangeCheck();

        m_ShowChannelRemapping = EditorGUILayout.Foldout(m_ShowChannelRemapping, terrainLayer.maskMapTexture != null ? s_Styles.channelRemapping : s_Styles.defaultValues);

        if (m_ShowChannelRemapping)
        {
            if (terrainLayer.maskMapTexture != null)
            {
                float min, max;
                min = maskMapRemapMin.x; max = maskMapRemapMax.x;
                EditorGUILayout.MinMaxSlider(s_Styles.metallic, ref min, ref max, 0, 1);
                maskMapRemapMin.x = min; maskMapRemapMax.x = max;

                min = maskMapRemapMin.y; max = maskMapRemapMax.y;
                EditorGUILayout.MinMaxSlider(s_Styles.ao, ref min, ref max, 0, 1);
                maskMapRemapMin.y = min; maskMapRemapMax.y = max;

                if (heightBlend)
                {
                    EditorGUILayout.LabelField(styles.height);
                    ++EditorGUI.indentLevel;
                    m_HeightParametrization = (HeightParametrization)EditorGUILayout.EnumPopup(styles.heightParametrization, m_HeightParametrization);
                    if (m_HeightParametrization == HeightParametrization.Amplitude)
                    {
                        // (height - heightBase) * amplitude
                        float amplitude = Mathf.Max(maskMapRemapMax.z - maskMapRemapMin.z, Mathf.Epsilon); // to avoid divide by zero
                        float heightBase = maskMapRemapMin.z / amplitude;
                        amplitude = EditorGUILayout.FloatField(styles.heightAmplitude, amplitude * 100) / 100;
                        heightBase = EditorGUILayout.FloatField(styles.heightBase, heightBase * 100) / 100;
                        maskMapRemapMin.z = heightBase * amplitude;
                        maskMapRemapMax.z = (1.0f - heightBase) * amplitude;
                    }
                    else
                    {
                        maskMapRemapMin.z = EditorGUILayout.FloatField(styles.heightMin, maskMapRemapMin.z * 100) / 100;
                        maskMapRemapMax.z = EditorGUILayout.FloatField(styles.heightMax, maskMapRemapMax.z * 100) / 100;
                    }
                    --EditorGUI.indentLevel;
                }

                min = maskMapRemapMin.w; max = maskMapRemapMax.w;
                EditorGUILayout.MinMaxSlider(s_Styles.smoothness, ref min, ref max, 0, 1);
                maskMapRemapMin.w = min; maskMapRemapMax.w = max;
            }
            else
            {
                metallic = EditorGUILayout.Slider(s_Styles.metallic, metallic, 0, 1);
                // AO and Height are still exclusively controlled via the maskRemap controls
                // metallic and smoothness have their own values as fields within the LayerData.
                maskMapRemapMax.y = EditorGUILayout.Slider(s_Styles.ao, maskMapRemapMax.y, 0, 1);
                if (heightBlend)
                {
                    maskMapRemapMax.z = EditorGUILayout.FloatField(s_Styles.heightCm, maskMapRemapMax.z * 100) / 100;
                }

                // There's a possibility that someone could slide max below the existing min value
                // so we'll just protect against that by locking the min value down a little bit.
                // In the case of height (Z), we are trying to set min to no lower than zero value unless
                // max goes negative.  Zero is a good sensible value for the minimum.  For AO (Y), we
                // don't need this extra protection step because the UI blocks us from going negative
                // anyway.  In both cases, pushing the slider below the min value will lock them together,
                // but min will be "left behind" if you go back up.
                maskMapRemapMin.y = Mathf.Min(maskMapRemapMin.y, maskMapRemapMax.y);
                maskMapRemapMin.z = Mathf.Min(Mathf.Max(0, maskMapRemapMin.z), maskMapRemapMax.z);

                if (TextureHasAlpha(terrainLayer.diffuseTexture))
                {
                    GUIStyle warnStyle = new GUIStyle(GUI.skin.label);
                    warnStyle.wordWrap = true;
                    GUILayout.Label("Smoothness is controlled by diffuse alpha channel", warnStyle);
                }
                else
                    smoothness = EditorGUILayout.Slider(s_Styles.smoothness, smoothness, 0, 1);
            }
        }

        if (EditorGUI.EndChangeCheck())
        {
            terrainLayer.maskMapRemapMin = maskMapRemapMin;
            terrainLayer.maskMapRemapMax = maskMapRemapMax;
            terrainLayer.smoothness = smoothness;
            terrainLayer.metallic = metallic;
        }
        --EditorGUI.indentLevel;

        EditorGUILayout.Space();
        TerrainLayerUtility.TilingSettingsUI(terrainLayer);

        return true;
    }
}
}