mathe/Library/PackageCache/com.unity.shadergraph@14.0.8/Editor/Data/Nodes/UV/ParallaxOcclusionMappingNode.cs
2024-09-20 20:30:10 +02:00

249 lines
12 KiB
C#

using UnityEngine;
using UnityEditor.Graphing;
using System.Linq;
using UnityEditor.ShaderGraph.Internal;
using UnityEditor.ShaderGraph.Drawing.Controls;
namespace UnityEditor.ShaderGraph
{
[Title("UV", "Parallax Occlusion Mapping")]
[FormerName("UnityEditor.Experimental.Rendering.HDPipeline.ParallaxOcclusionMappingNode")]
[FormerName("UnityEditor.Rendering.HighDefinition.ParallaxOcclusionMappingNode")]
class ParallaxOcclusionMappingNode : AbstractMaterialNode, IGeneratesBodyCode, IGeneratesFunction, IMayRequireViewDirection, IMayRequireMeshUV
{
public ParallaxOcclusionMappingNode()
{
name = "Parallax Occlusion Mapping";
synonyms = new string[] { "pom" };
UpdateNodeAfterDeserialization();
}
// Input slots
private const int kHeightmapSlotId = 2;
private const string kHeightmapSlotName = "Heightmap";
private const int kHeightmapSamplerSlotId = 3;
private const string kHeightmapSamplerSlotName = "HeightmapSampler";
private const int kAmplitudeSlotId = 4;
private const string kAmplitudeSlotName = "Amplitude";
private const int kStepsSlotId = 5;
private const string kStepsSlotName = "Steps";
private const int kUVsSlotId = 6;
private const string kUVsSlotName = "UVs";
private const int kLodSlotId = 7;
private const string kLodSlotName = "LOD";
private const int kLodThresholdSlotId = 8;
private const string kLodThresholdSlotName = "LODThreshold";
private const int kTilingSlotId = 10;
private const string kTilingSlotName = "Tiling";
private const int kOffsetSlotId = 11;
private const string kOffsetSlotName = "Offset";
private const int kPrimitiveSizeSlotId = 12;
private const string kPrimitiveSizeSlotName = "PrimitiveSize";
// Output slots
private const int kPixelDepthOffsetOutputSlotId = 0;
private const string kPixelDepthOffsetOutputSlotName = "PixelDepthOffset";
private const int kParallaxUVsOutputSlotId = 1;
private const string kParallaxUVsOutputSlotName = "ParallaxUVs";
public override bool hasPreview { get { return false; } }
[SerializeField]
private Channel m_Channel = Channel.Red;
[EnumControl("Heightmap Sample Channel")]
public Channel channel
{
get { return m_Channel; }
set
{
if (m_Channel == value)
return;
m_Channel = value;
Dirty(ModificationScope.Graph);
}
}
public sealed override void UpdateNodeAfterDeserialization()
{
AddSlot(new Texture2DInputMaterialSlot(kHeightmapSlotId, kHeightmapSlotName, kHeightmapSlotName, ShaderStageCapability.Fragment));
AddSlot(new SamplerStateMaterialSlot(kHeightmapSamplerSlotId, kHeightmapSamplerSlotName, kHeightmapSamplerSlotName, SlotType.Input));
AddSlot(new Vector1MaterialSlot(kAmplitudeSlotId, kAmplitudeSlotName, kAmplitudeSlotName, SlotType.Input, 1.0f, ShaderStageCapability.Fragment));
AddSlot(new Vector1MaterialSlot(kStepsSlotId, kStepsSlotName, kStepsSlotName, SlotType.Input, 5.0f, ShaderStageCapability.Fragment));
AddSlot(new UVMaterialSlot(kUVsSlotId, kUVsSlotName, kUVsSlotName, UVChannel.UV0, ShaderStageCapability.Fragment));
AddSlot(new Vector2MaterialSlot(kTilingSlotId, kTilingSlotName, kTilingSlotName, SlotType.Input, Vector2.one, ShaderStageCapability.Fragment));
AddSlot(new Vector2MaterialSlot(kOffsetSlotId, kOffsetSlotName, kOffsetSlotName, SlotType.Input, Vector2.zero, ShaderStageCapability.Fragment));
AddSlot(new Vector2MaterialSlot(kPrimitiveSizeSlotId, kPrimitiveSizeSlotName, kPrimitiveSizeSlotName, SlotType.Input, Vector2.one, ShaderStageCapability.Fragment));
AddSlot(new Vector1MaterialSlot(kLodSlotId, kLodSlotName, kLodSlotName, SlotType.Input, 0.0f, ShaderStageCapability.Fragment));
AddSlot(new Vector1MaterialSlot(kLodThresholdSlotId, kLodThresholdSlotName, kLodThresholdSlotName, SlotType.Input, 0.0f, ShaderStageCapability.Fragment));
AddSlot(new Vector1MaterialSlot(kPixelDepthOffsetOutputSlotId, kPixelDepthOffsetOutputSlotName, kPixelDepthOffsetOutputSlotName, SlotType.Output, 0.0f, ShaderStageCapability.Fragment));
AddSlot(new Vector2MaterialSlot(kParallaxUVsOutputSlotId, kParallaxUVsOutputSlotName, kParallaxUVsOutputSlotName, SlotType.Output, Vector2.zero, ShaderStageCapability.Fragment));
RemoveSlotsNameNotMatching(new[]
{
kPixelDepthOffsetOutputSlotId,
kParallaxUVsOutputSlotId,
kHeightmapSlotId,
kHeightmapSamplerSlotId,
kAmplitudeSlotId,
kStepsSlotId,
kUVsSlotId,
kLodSlotId,
kLodThresholdSlotId,
kTilingSlotId,
kOffsetSlotId,
kPrimitiveSizeSlotId
});
}
string GetFunctionName() => GetVariableNameForNode() + "_$precision";
public override void Setup()
{
base.Setup();
var textureSlot = FindInputSlot<Texture2DInputMaterialSlot>(kHeightmapSlotId);
textureSlot.defaultType = Texture2DShaderProperty.DefaultType.Black;
}
public void GenerateNodeFunction(FunctionRegistry registry, GenerationMode generationMode)
{
// we don't declare this include via the registry include path
// because it uses macro magic, and can be included more than once, generating different functions
string perPixelDisplacementInclude = @"#include ""Packages/com.unity.render-pipelines.core/ShaderLibrary/PerPixelDisplacement.hlsl""";
// Texture sample inputs
var samplerSlot = FindInputSlot<MaterialSlot>(kHeightmapSamplerSlotId);
var edgesSampler = owner.GetEdges(samplerSlot.slotReference);
var heightmap = GetSlotValue(kHeightmapSlotId, generationMode);
// We first generate components that can be used by multiple POM node
registry.ProvideFunction("PerPixelHeightDisplacementParam", s =>
{
s.AppendLine("struct PerPixelHeightDisplacementParam");
using (s.BlockSemicolonScope())
{
s.AppendLine("float2 uv;");
}
s.AppendNewLine();
});
registry.ProvideFunction("GetDisplacementObjectScale_$precision", s =>
{
s.AppendLine($"$precision3 GetDisplacementObjectScale_$precision()");
using (s.BlockScope())
{
s.AppendLines(@"
float3 objectScale = float3(1.0, 1.0, 1.0);
float4x4 worldTransform = GetWorldToObjectMatrix();
objectScale.x = length(float3(worldTransform._m00, worldTransform._m01, worldTransform._m02));
objectScale.z = length(float3(worldTransform._m20, worldTransform._m21, worldTransform._m22));
return objectScale;");
}
});
// Then we add the functions that are specific to this node
registry.ProvideFunction(GetFunctionName(), s =>
{
s.AppendLine("// Required struct and function for the ParallaxOcclusionMapping function:");
s.AppendLine($"$precision ComputePerPixelHeightDisplacement_{GetVariableNameForNode()}($precision2 texOffsetCurrent, $precision lod, PerPixelHeightDisplacementParam param, TEXTURE2D_PARAM(heightTexture, heightSampler))");
using (s.BlockScope())
{
s.AppendLine("return SAMPLE_TEXTURE2D_LOD(heightTexture, heightSampler, param.uv + texOffsetCurrent, lod)[{0}];", (int)channel);
}
// heightmap,
// edgesSampler.Any() ? GetSlotValue(kHeightmapSamplerSlotId, generationMode) : "sampler" + heightmap);
s.AppendLine($"#define ComputePerPixelHeightDisplacement ComputePerPixelHeightDisplacement_{GetVariableNameForNode()}");
s.AppendLine($"#define POM_NAME_ID {GetFunctionName()}");
s.AppendLine($"#define POM_USER_DATA_PARAMETERS , TEXTURE2D_PARAM(heightTexture, samplerState)");
s.AppendLine($"#define POM_USER_DATA_ARGUMENTS , TEXTURE2D_ARGS(heightTexture, samplerState)");
s.AppendLine(perPixelDisplacementInclude);
s.AppendLine($"#undef ComputePerPixelHeightDisplacement");
s.AppendLine($"#undef POM_NAME_ID");
s.AppendLine($"#undef POM_USER_DATA_PARAMETERS");
s.AppendLine($"#undef POM_USER_DATA_ARGUMENTS");
});
}
public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
{
string amplitude = GetSlotValue(kAmplitudeSlotId, generationMode);
string steps = GetSlotValue(kStepsSlotId, generationMode);
string uvs = GetSlotValue(kUVsSlotId, generationMode);
string tiling = GetSlotValue(kTilingSlotId, generationMode);
string offset = GetSlotValue(kOffsetSlotId, generationMode);
string primitiveSize = GetSlotValue(kPrimitiveSizeSlotId, generationMode);
string lod = GetSlotValue(kLodSlotId, generationMode);
string lodThreshold = GetSlotValue(kLodThresholdSlotId, generationMode);
string heightmap = GetSlotValue(kHeightmapSlotId, generationMode);
string sampler = GetSlotValue(kHeightmapSamplerSlotId, generationMode);
string tmpPOMParam = GetVariableNameForNode() + "_POM";
string tmpViewDir = GetVariableNameForNode() + "_ViewDir";
string tmpNdotV = GetVariableNameForNode() + "_NdotV";
string tmpMaxHeight = GetVariableNameForNode() + "_MaxHeight";
string tmpViewDirUV = GetVariableNameForNode() + "_ViewDirUV";
string tmpOutHeight = GetVariableNameForNode() + "_OutHeight";
string tmpUVs = GetVariableNameForNode() + "_UVs";
string tmpUVSpaceScale = GetVariableNameForNode() + "_UVSpaceScale";
sb.AppendLines($@"
$precision3 {tmpViewDir} = IN.{CoordinateSpace.Tangent.ToVariableName(InterpolatorType.ViewDirection)} * GetDisplacementObjectScale_$precision().xzy;
$precision {tmpNdotV} = {tmpViewDir}.z;
$precision {tmpMaxHeight} = {amplitude} * 0.01; // cm in the interface so we multiply by 0.01 in the shader to convert in meter
{tmpMaxHeight} *= 2.0 / ( abs({tiling}.x) + abs({tiling}.y) ); // reduce height based on the tiling values
$precision2 {tmpUVSpaceScale} = {tmpMaxHeight} * {tiling} / {primitiveSize};
// Transform the view vector into the UV space.
$precision3 {tmpViewDirUV} = normalize($precision3({tmpViewDir}.xy * {tmpUVSpaceScale}, {tmpViewDir}.z)); // TODO: skip normalize
PerPixelHeightDisplacementParam {tmpPOMParam};
$precision2 {tmpUVs} = {uvs} * {tiling} + {offset};
{tmpPOMParam}.uv = {heightmap}.GetTransformedUV({tmpUVs});");
// to avoid crashes when steps gets too big, and
// to avoid divide by zero, we clamp it to the range [1, 256]
// This should compile out when steps is a static value.
steps = "max(min(" + steps + ", 256), 1)";
sb.AppendLines($@"
$precision {tmpOutHeight};
$precision2 {GetVariableNameForSlot(kParallaxUVsOutputSlotId)} = {heightmap}.GetTransformedUV({tmpUVs}) + ParallaxOcclusionMapping{GetFunctionName()}({lod}, {lodThreshold}, {steps}, {tmpViewDirUV}, {tmpPOMParam}, {tmpOutHeight}, TEXTURE2D_ARGS({heightmap}.tex, {sampler}.samplerstate));
$precision {GetVariableNameForSlot(kPixelDepthOffsetOutputSlotId)} = ({tmpMaxHeight} - {tmpOutHeight} * {tmpMaxHeight}) / max({tmpNdotV}, 0.0001);
");
}
public NeededCoordinateSpace RequiresViewDirection(ShaderStageCapability stageCapability = ShaderStageCapability.All)
{
return NeededCoordinateSpace.Tangent;
}
public bool RequiresMeshUV(UVChannel channel, ShaderStageCapability stageCapability)
{
using (var tempSlots = PooledList<MaterialSlot>.Get())
{
GetInputSlots(tempSlots);
var result = false;
foreach (var slot in tempSlots)
{
if (slot.RequiresMeshUV(channel))
{
result = true;
break;
}
}
tempSlots.Clear();
return result;
}
}
}
}