ScriptableRenderPipeline/com.unity.render-pipelines.high-definition/HDRP/Editor/Material/Decal/DecalUI.cs

using System;
using UnityEngine;
using UnityEngine.Experimental.Rendering;
using UnityEngine.Experimental.Rendering.HDPipeline;
using UnityEngine.Rendering;

namespace UnityEditor.Experimental.Rendering.HDPipeline
{
    public class DecalUI : ShaderGUI
    {
        protected static class Styles
        {
            public static string InputsText = "Inputs";

            public static GUIContent baseColorText = new GUIContent("BaseColor (RGB) and Opacity (A)", "BaseColor (RGB) and Opacity (A)");
            public static GUIContent baseColorText2 = new GUIContent("Opacity(A)", "Opacity (A)");
            public static GUIContent normalMapText = new GUIContent("Normal Map", "Normal Map (BC7/BC5/DXT5(nm))");
            public static GUIContent decalBlendText = new GUIContent("Global Opacity", "Whole decal Opacity");
            public static GUIContent AlbedoModeText = new GUIContent("Affect BaseColor", "Base color + Opacity, Opacity only");
 			public static GUIContent MeshDecalDepthBiasText = new GUIContent("Mesh decal depth bias", "prevents z-fighting");
	 		public static GUIContent DrawOrderText = new GUIContent("Draw order", "Controls draw order of decal projectors");

            public static GUIContent[] maskMapText =
            {
                new GUIContent("Error", "Mask map"), // Not possible
                new GUIContent("Mask Map - M(R), Opacity(B)", "Mask map - Metal(R), Opacity(B)"), // Decal.MaskBlendFlags.Metal:
                new GUIContent("Mask Map - AO(G), Opacity(B)", "Mask map - Ambient Occlusion(G), Opacity(B)"), // Decal.MaskBlendFlags.AO:
                new GUIContent("Mask Map - M(R), AO(G), Opacity(B)", "Mask map - Metal(R), Ambient Occlusion(G), Opacity(B)"), // Decal.MaskBlendFlags.Metal | Decal.MaskBlendFlags.AO:
                new GUIContent("Mask Map - Opacity(B), S(A)", "Mask map - Opacity(B), Smoothness(A)"), // Decal.MaskBlendFlags.Smoothness:
                new GUIContent("Mask Map - M(R), Opacity(B), S(A)", "Mask map - Metal(R), Opacity(B), Smoothness(A)"), // Decal.MaskBlendFlags.Metal | Decal.MaskBlendFlags.Smoothness:
                new GUIContent("Mask Map - AO(G), Opacity(B), S(A)", "Mask map - Ambient Occlusion(G), Opacity(B), Smoothness(A)"), // Decal.MaskBlendFlags.AO | Decal.MaskBlendFlags.Smoothness:
                new GUIContent("Mask Map - M(R), AO(G), Opacity(B), S(A)", "Mask map - Metal(R), Ambient Occlusion(G), Opacity(B), Smoothness(A)") // Decal.MaskBlendFlags.Metal | Decal.MaskBlendFlags.AO | Decal.MaskBlendFlags.Smoothness:
            };
        }

        enum BlendSource
        {
            BaseColorMapAlpha,
            MaskMapBlue
        }
        protected string[] blendSourceNames = Enum.GetNames(typeof(BlendSource));

        protected string[] blendModeNames = Enum.GetNames(typeof(BlendMode));

        protected MaterialProperty baseColorMap = new MaterialProperty();
        protected const string kBaseColorMap = "_BaseColorMap";

        protected MaterialProperty baseColor = new MaterialProperty();
        protected const string kBaseColor = "_BaseColor";

        protected MaterialProperty normalMap = new MaterialProperty();
        protected const string kNormalMap = "_NormalMap";

        protected MaterialProperty maskMap = new MaterialProperty();
        protected const string kMaskMap = "_MaskMap";

        protected MaterialProperty decalBlend = new MaterialProperty();
        protected const string kDecalBlend = "_DecalBlend";

        protected MaterialProperty albedoMode = new MaterialProperty();
        protected const string kAlbedoMode = "_AlbedoMode";

        protected MaterialProperty normalBlendSrc = new MaterialProperty();
        protected const string kNormalBlendSrc = "_NormalBlendSrc";

        protected MaterialProperty maskBlendSrc = new MaterialProperty();
        protected const string kMaskBlendSrc = "_MaskBlendSrc";

        protected MaterialProperty maskBlendMode = new MaterialProperty();
        protected const string kMaskBlendMode = "_MaskBlendMode";

        protected MaterialProperty maskmapMetal = new MaterialProperty();
        protected const string kMaskmapMetal = "_MaskmapMetal";

        protected MaterialProperty maskmapAO = new MaterialProperty();
        protected const string kMaskmapAO = "_MaskmapAO";

        protected MaterialProperty maskmapSmoothness = new MaterialProperty();
        protected const string kMaskmapSmoothness = "_MaskmapSmoothness";

        protected MaterialProperty decalMeshDepthBias = new MaterialProperty();
        protected const string kDecalMeshDepthBias = "_DecalMeshDepthBias";

        protected MaterialProperty drawOrder = new MaterialProperty();
        protected const string kDrawOrder = "_DrawOrder";

        protected MaterialEditor m_MaterialEditor;

        // This is call by the inspector

        void FindMaterialProperties(MaterialProperty[] props)
        {
            baseColor = FindProperty(kBaseColor, props);
            baseColorMap = FindProperty(kBaseColorMap, props);
            normalMap = FindProperty(kNormalMap, props);
            maskMap = FindProperty(kMaskMap, props);
            decalBlend = FindProperty(kDecalBlend, props);
            albedoMode = FindProperty(kAlbedoMode, props);
            normalBlendSrc = FindProperty(kNormalBlendSrc, props);
            maskBlendSrc = FindProperty(kMaskBlendSrc, props);
            maskBlendMode = FindProperty(kMaskBlendMode, props);
            maskmapMetal = FindProperty(kMaskmapMetal, props);
            maskmapAO = FindProperty(kMaskmapAO, props);
            maskmapSmoothness = FindProperty(kMaskmapSmoothness, props);            
            decalMeshDepthBias = FindProperty(kDecalMeshDepthBias, props);            
            drawOrder = FindProperty(kDrawOrder, props);

            // always instanced
            SerializedProperty instancing = m_MaterialEditor.serializedObject.FindProperty("m_EnableInstancingVariants");
            instancing.boolValue = true;
        }

        // All Setup Keyword functions must be static. It allow to create script to automatically update the shaders with a script if code change
        static public void SetupMaterialKeywordsAndPass(Material material)
        {
            Decal.MaskBlendFlags blendMode = (Decal.MaskBlendFlags)material.GetFloat(kMaskBlendMode);

            CoreUtils.SetKeyword(material, "_ALBEDOCONTRIBUTION", material.GetFloat(kAlbedoMode) == 1.0f);
            CoreUtils.SetKeyword(material, "_COLORMAP", material.GetTexture(kBaseColorMap));
            CoreUtils.SetKeyword(material, "_NORMALMAP", material.GetTexture(kNormalMap));
            CoreUtils.SetKeyword(material, "_MASKMAP", material.GetTexture(kMaskMap)); 

            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsAOStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMAOStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsSStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMSStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsAOSStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMAOSStr, false);
            material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecals3RTStr, true);
            switch (blendMode)
            {
                case Decal.MaskBlendFlags.Metal:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMStr, true);
                    break;

                case Decal.MaskBlendFlags.AO:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsAOStr, true);
                    break;

                case Decal.MaskBlendFlags.Metal | Decal.MaskBlendFlags.AO:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMAOStr, true);
                    break;

                case Decal.MaskBlendFlags.Smoothness:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsSStr, true);
                    break;

                case Decal.MaskBlendFlags.Metal | Decal.MaskBlendFlags.Smoothness:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMSStr, true);
                    break;

                case Decal.MaskBlendFlags.AO | Decal.MaskBlendFlags.Smoothness:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsAOSStr, true);
                    break;

                case Decal.MaskBlendFlags.Metal | Decal.MaskBlendFlags.AO | Decal.MaskBlendFlags.Smoothness:
                    material.SetShaderPassEnabled(HDShaderPassNames.s_MeshDecalsMAOSStr, true);
                    break;
            }
        }

        protected void SetupMaterialKeywordsAndPassInternal(Material material)
        {
            SetupMaterialKeywordsAndPass(material);
        }

        public void ShaderPropertiesGUI(Material material)
        {
            // Use default labelWidth
            EditorGUIUtility.labelWidth = 0f;
            float normalBlendSrcValue = normalBlendSrc.floatValue;
            float maskBlendSrcValue =  maskBlendSrc.floatValue;

            Decal.MaskBlendFlags maskBlendFlags = (Decal.MaskBlendFlags)maskBlendMode.floatValue;              

            HDRenderPipelineAsset hdrp = GraphicsSettings.renderPipelineAsset as HDRenderPipelineAsset;
            bool perChannelMask = hdrp.renderPipelineSettings.decalSettings.perChannelMask;

            // Detect any changes to the material
            EditorGUI.BeginChangeCheck();
            {
                EditorGUILayout.LabelField(Styles.InputsText, EditorStyles.boldLabel);

                EditorGUI.indentLevel++;

                m_MaterialEditor.TexturePropertySingleLine((material.GetFloat(kAlbedoMode) == 1.0f) ? Styles.baseColorText : Styles.baseColorText2, baseColorMap, baseColor);
                // Currently always display Albedo contribution as we have an albedo tint that apply
                EditorGUI.indentLevel++;
                m_MaterialEditor.ShaderProperty(albedoMode, Styles.AlbedoModeText);
                EditorGUI.indentLevel--;

                m_MaterialEditor.TexturePropertySingleLine(Styles.normalMapText, normalMap);
                if (material.GetTexture(kNormalMap))
                {
                    EditorGUI.indentLevel++;
                    normalBlendSrcValue = EditorGUILayout.Popup("Normal Opacity channel", (int)normalBlendSrcValue, blendSourceNames);
                    EditorGUI.indentLevel--;
                }

                m_MaterialEditor.TexturePropertySingleLine(Styles.maskMapText[(int)maskBlendFlags], maskMap);
                if (material.GetTexture(kMaskMap))
                {
                    EditorGUI.indentLevel++;
                    maskBlendSrcValue = EditorGUILayout.Popup("Mask Opacity channel", (int) maskBlendSrcValue, blendSourceNames);
                    if (perChannelMask)
                    {
                        // Following condition force users to always have at least one attribute enabled
                        m_MaterialEditor.ShaderProperty(maskmapMetal, "Affect Metal");
                        if ((maskmapMetal.floatValue == 0.0f) && (maskmapAO.floatValue == 0.0f) && (maskmapSmoothness.floatValue == 0.0f))
                            maskmapMetal.floatValue = 1.0f;
                        m_MaterialEditor.ShaderProperty(maskmapAO, "Affect AO");
                        if ((maskmapMetal.floatValue == 0.0f) && (maskmapAO.floatValue == 0.0f) && (maskmapSmoothness.floatValue == 0.0f))
                            maskmapAO.floatValue = 1.0f;
                        m_MaterialEditor.ShaderProperty(maskmapSmoothness, "Affect Smoothness");
                        if ((maskmapMetal.floatValue == 0.0f) && (maskmapAO.floatValue == 0.0f) && (maskmapSmoothness.floatValue == 0.0f))
                            maskmapSmoothness.floatValue = 1.0f;

                        maskBlendFlags = 0; // Re-init the mask

                        if (maskmapMetal.floatValue == 1.0f)
                            maskBlendFlags |= Decal.MaskBlendFlags.Metal;
                        if (maskmapAO.floatValue == 1.0f)
                            maskBlendFlags |= Decal.MaskBlendFlags.AO;
                        if (maskmapSmoothness.floatValue == 1.0f)
                            maskBlendFlags |= Decal.MaskBlendFlags.Smoothness;
                    }
                    else // if perChannelMask is not enabled, force to have smoothness
                    {
                        maskBlendFlags = Decal.MaskBlendFlags.Smoothness;
                    }
                    EditorGUI.indentLevel--;
                }

                m_MaterialEditor.ShaderProperty(drawOrder, Styles.DrawOrderText);
                m_MaterialEditor.ShaderProperty(decalMeshDepthBias, Styles.MeshDecalDepthBiasText);
                m_MaterialEditor.ShaderProperty(decalBlend, Styles.decalBlendText);                

                EditorGUI.indentLevel--;

                EditorGUILayout.HelpBox(
                    "Control of AO and Metal is based on option 'Enable Metal and AO properties' in HDRP Asset.\nThere is a performance cost of enabling this option.",
                    MessageType.Info);
            }

            if (EditorGUI.EndChangeCheck())
            {
                normalBlendSrc.floatValue = normalBlendSrcValue;
                maskBlendSrc.floatValue = maskBlendSrcValue;
                maskBlendMode.floatValue = (float) maskBlendFlags;
                foreach (var obj in m_MaterialEditor.targets)
                    SetupMaterialKeywordsAndPassInternal((Material)obj);
            }
        }

        public override void OnGUI(MaterialEditor materialEditor, MaterialProperty[] props)
        {
            m_MaterialEditor = materialEditor;
            // We should always do this call at the beginning
            m_MaterialEditor.serializedObject.Update();

            FindMaterialProperties(props);

            Material material = materialEditor.target as Material;
            ShaderPropertiesGUI(material);

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