Singularity/Library/PackageCache/com.unity.render-pipelines..../Runtime/LightCookieManager.cs

1012 lines
43 KiB
C#
Raw Normal View History

2024-05-06 14:45:45 -04:00
using System;
using System.Runtime.InteropServices;
using UnityEngine.Experimental.Rendering;
using Unity.Mathematics;
namespace UnityEngine.Rendering.Universal
{
internal class LightCookieManager : IDisposable
{
static class ShaderProperty
{
public static readonly int mainLightTexture = Shader.PropertyToID("_MainLightCookieTexture");
public static readonly int mainLightWorldToLight = Shader.PropertyToID("_MainLightWorldToLight");
public static readonly int mainLightCookieTextureFormat = Shader.PropertyToID("_MainLightCookieTextureFormat");
public static readonly int additionalLightsCookieAtlasTexture = Shader.PropertyToID("_AdditionalLightsCookieAtlasTexture");
public static readonly int additionalLightsCookieAtlasTextureFormat = Shader.PropertyToID("_AdditionalLightsCookieAtlasTextureFormat");
public static readonly int additionalLightsCookieEnableBits = Shader.PropertyToID("_AdditionalLightsCookieEnableBits");
public static readonly int additionalLightsCookieAtlasUVRectBuffer = Shader.PropertyToID("_AdditionalLightsCookieAtlasUVRectBuffer");
public static readonly int additionalLightsCookieAtlasUVRects = Shader.PropertyToID("_AdditionalLightsCookieAtlasUVRects");
// TODO: these should be generic light property
public static readonly int additionalLightsWorldToLightBuffer = Shader.PropertyToID("_AdditionalLightsWorldToLightBuffer");
public static readonly int additionalLightsLightTypeBuffer = Shader.PropertyToID("_AdditionalLightsLightTypeBuffer");
public static readonly int additionalLightsWorldToLights = Shader.PropertyToID("_AdditionalLightsWorldToLights");
public static readonly int additionalLightsLightTypes = Shader.PropertyToID("_AdditionalLightsLightTypes");
}
private enum LightCookieShaderFormat
{
None = -1,
RGB = 0,
Alpha = 1,
Red = 2
}
public struct Settings
{
public struct AtlasSettings
{
public Vector2Int resolution;
public GraphicsFormat format;
public bool useMips;
public bool isPow2 => Mathf.IsPowerOfTwo(resolution.x) && Mathf.IsPowerOfTwo(resolution.y);
public bool isSquare => resolution.x == resolution.y;
}
public AtlasSettings atlas;
public int maxAdditionalLights; // UniversalRenderPipeline.maxVisibleAdditionalLights;
public float cubeOctahedralSizeScale; // Cube octahedral projection size scale.
public bool useStructuredBuffer; // RenderingUtils.useStructuredBuffer
public static Settings GetDefault()
{
Settings s;
s.atlas.resolution = new Vector2Int(1024, 1024);
s.atlas.format = GraphicsFormat.R8G8B8A8_SRGB;
s.atlas.useMips = false; // TODO: set to true, make sure they work proper first! Disable them for now...
s.maxAdditionalLights = UniversalRenderPipeline.maxVisibleAdditionalLights;
// (Scale * W * Scale * H) / (6 * WH) == (Scale^2 / 6)
// 1: 1/6 = 16%, 2: 4/6 = 66%, 4: 16/6 == 266% of cube pixels
// 100% cube pixels == sqrt(6) ~= 2.45f --> 2.5;
s.cubeOctahedralSizeScale = s.atlas.useMips && s.atlas.isPow2 ? 2.0f : 2.5f;
s.useStructuredBuffer = RenderingUtils.useStructuredBuffer;
return s;
}
}
private struct Sorting
{
public static void QuickSort<T>(T[] data, Func<T, T, int> compare)
{
QuickSort<T>(data, 0, data.Length - 1, compare);
}
// A non-allocating predicated sub-array quick sort.
// NOTE: Similar to UnityEngine.Rendering.CoreUnsafeUtils.QuickSort in CoreUnsafeUtils.cs,
// we should see if these could be merged in the future.
// For example: Sorting.QuickSort(test, 0, test.Length - 1, (int a, int b) => a - b);
public static void QuickSort<T>(T[] data, int start, int end, Func<T, T, int> compare)
{
int diff = end - start;
if (diff < 1)
return;
if (diff < 8)
{
InsertionSort(data, start, end, compare);
return;
}
Assertions.Assert.IsTrue((uint)start < data.Length);
Assertions.Assert.IsTrue((uint)end < data.Length); // end == inclusive
if (start < end)
{
int pivot = Partition<T>(data, start, end, compare);
if (pivot >= 1)
QuickSort<T>(data, start, pivot, compare);
if (pivot + 1 < end)
QuickSort<T>(data, pivot + 1, end, compare);
}
}
static T Median3Pivot<T>(T[] data, int start, int pivot, int end, Func<T, T, int> compare)
{
void Swap(int a, int b)
{
var tmp = data[a];
data[a] = data[b];
data[b] = tmp;
}
if (compare(data[end], data[start]) < 0) Swap(start, end);
if (compare(data[pivot], data[start]) < 0) Swap(start, pivot);
if (compare(data[end], data[pivot]) < 0) Swap(pivot, end);
return data[pivot];
}
static int Partition<T>(T[] data, int start, int end, Func<T, T, int> compare)
{
int diff = end - start;
int pivot = start + diff / 2;
var pivotValue = Median3Pivot(data, start, pivot, end, compare);
while (true)
{
while (compare(data[start], pivotValue) < 0) ++start;
while (compare(data[end], pivotValue) > 0) --end;
if (start >= end)
{
return end;
}
var tmp = data[start];
data[start++] = data[end];
data[end--] = tmp;
}
}
// A non-allocating predicated sub-array insertion sort.
static public void InsertionSort<T>(T[] data, int start, int end, Func<T, T, int> compare)
{
Assertions.Assert.IsTrue((uint)start < data.Length);
Assertions.Assert.IsTrue((uint)end < data.Length);
for (int i = start + 1; i < end + 1; i++)
{
var iData = data[i];
int j = i - 1;
while (j >= 0 && compare(iData, data[j]) < 0)
{
data[j + 1] = data[j];
j--;
}
data[j + 1] = iData;
}
}
}
private struct LightCookieMapping
{
public ushort visibleLightIndex; // Index into visible light (src)
public ushort lightBufferIndex; // Index into light shader data buffer (dst)
public Light light; // Cached built-in light for the visibleLightIndex. Avoids multiple copies on all the gets from native array.
public static Func<LightCookieMapping, LightCookieMapping, int> s_CompareByCookieSize = (LightCookieMapping a, LightCookieMapping b) =>
{
var alc = a.light.cookie;
var blc = b.light.cookie;
int a2 = alc.width * alc.height;
int b2 = blc.width * blc.height;
int d = b2 - a2;
if (d == 0)
{
// Sort by texture ID if "undecided" to batch fetches to the same cookie texture.
int ai = alc.GetInstanceID();
int bi = blc.GetInstanceID();
return ai - bi;
}
return d;
};
public static Func<LightCookieMapping, LightCookieMapping, int> s_CompareByBufferIndex = (LightCookieMapping a, LightCookieMapping b) =>
{
return a.lightBufferIndex - b.lightBufferIndex;
};
}
private readonly struct WorkSlice<T>
{
private readonly T[] m_Data;
private readonly int m_Start;
private readonly int m_Length;
public WorkSlice(T[] src, int srcLen = -1) : this(src, 0, srcLen) { }
public WorkSlice(T[] src, int srcStart, int srcLen = -1)
{
m_Data = src;
m_Start = srcStart;
m_Length = (srcLen < 0) ? src.Length : Math.Min(srcLen, src.Length);
Assertions.Assert.IsTrue(m_Start + m_Length <= capacity);
}
public T this[int index]
{
get => m_Data[m_Start + index];
set => m_Data[m_Start + index] = value;
}
public int length => m_Length;
public int capacity => m_Data.Length;
public void Sort(Func<T, T, int> compare)
{
if (m_Length > 1)
Sorting.QuickSort(m_Data, m_Start, m_Start + m_Length - 1, compare);
}
}
// Persistent work/temp memory of [] data.
private class WorkMemory
{
public LightCookieMapping[] lightMappings;
public Vector4[] uvRects;
public void Resize(int size)
{
if (size <= lightMappings?.Length)
return;
// Avoid allocs on every tiny size change.
size = Math.Max(size, ((size + 15) / 16) * 16);
lightMappings = new LightCookieMapping[size];
uvRects = new Vector4[size];
}
}
private struct ShaderBitArray
{
const int k_BitsPerElement = 32;
const int k_ElementShift = 5;
const int k_ElementMask = (1 << k_ElementShift) - 1;
private float[] m_Data;
public int elemLength => m_Data == null ? 0 : m_Data.Length;
public int bitCapacity => elemLength * k_BitsPerElement;
public float[] data => m_Data;
public void Resize(int bitCount)
{
if (bitCapacity > bitCount)
return;
int newElemCount = ((bitCount + (k_BitsPerElement - 1)) / k_BitsPerElement);
if (newElemCount == m_Data?.Length)
return;
var newData = new float[newElemCount];
if (m_Data != null)
{
for (int i = 0; i < m_Data.Length; i++)
newData[i] = m_Data[i];
}
m_Data = newData;
}
public void Clear()
{
for (int i = 0; i < m_Data.Length; i++)
m_Data[i] = 0;
}
private void GetElementIndexAndBitOffset(int index, out int elemIndex, out int bitOffset)
{
elemIndex = index >> k_ElementShift;
bitOffset = index & k_ElementMask;
}
public bool this[int index]
{
get
{
GetElementIndexAndBitOffset(index, out var elemIndex, out var bitOffset);
unsafe
{
fixed (float* floatData = m_Data)
{
uint* uintElem = (uint*)&floatData[elemIndex];
bool val = ((*uintElem) & (1u << bitOffset)) != 0u;
return val;
}
}
}
set
{
GetElementIndexAndBitOffset(index, out var elemIndex, out var bitOffset);
unsafe
{
fixed (float* floatData = m_Data)
{
uint* uintElem = (uint*)&floatData[elemIndex];
if (value == true)
*uintElem = (*uintElem) | (1u << bitOffset);
else
*uintElem = (*uintElem) & ~(1u << bitOffset);
}
}
}
}
public override string ToString()
{
unsafe
{
Debug.Assert(bitCapacity < 4096, "Bit string too long! It was truncated!");
int len = Math.Min(bitCapacity, 4096);
byte* buf = stackalloc byte[len];
for (int i = 0; i < len; i++)
{
buf[i] = (byte)(this[i] ? '1' : '0');
}
return new string((sbyte*)buf, 0, len, System.Text.Encoding.UTF8);
}
}
}
/// Must match light data layout.
private class LightCookieShaderData : IDisposable
{
int m_Size = 0;
bool m_UseStructuredBuffer;
// Shader data CPU arrays, used to upload the data to GPU
Matrix4x4[] m_WorldToLightCpuData;
Vector4[] m_AtlasUVRectCpuData;
float[] m_LightTypeCpuData;
ShaderBitArray m_CookieEnableBitsCpuData;
// Compute buffer counterparts for the CPU data
ComputeBuffer m_WorldToLightBuffer; // TODO: WorldToLight matrices should be general property of lights!!
ComputeBuffer m_AtlasUVRectBuffer;
ComputeBuffer m_LightTypeBuffer;
public Matrix4x4[] worldToLights => m_WorldToLightCpuData;
public ShaderBitArray cookieEnableBits => m_CookieEnableBitsCpuData;
public Vector4[] atlasUVRects => m_AtlasUVRectCpuData;
public float[] lightTypes => m_LightTypeCpuData;
public bool isUploaded { get; set; }
public LightCookieShaderData(int size, bool useStructuredBuffer)
{
m_UseStructuredBuffer = useStructuredBuffer;
Resize(size);
}
public void Dispose()
{
if (m_UseStructuredBuffer)
{
m_WorldToLightBuffer?.Dispose();
m_AtlasUVRectBuffer?.Dispose();
m_LightTypeBuffer?.Dispose();
}
}
public void Resize(int size)
{
if (size <= m_Size)
return;
if (m_Size > 0)
Dispose();
m_WorldToLightCpuData = new Matrix4x4[size];
m_AtlasUVRectCpuData = new Vector4[size];
m_LightTypeCpuData = new float[size];
m_CookieEnableBitsCpuData.Resize(size);
if (m_UseStructuredBuffer)
{
m_WorldToLightBuffer = new ComputeBuffer(size, Marshal.SizeOf<Matrix4x4>());
m_AtlasUVRectBuffer = new ComputeBuffer(size, Marshal.SizeOf<Vector4>());
m_LightTypeBuffer = new ComputeBuffer(size, Marshal.SizeOf<float>());
}
m_Size = size;
}
public void Upload(CommandBuffer cmd)
{
if (m_UseStructuredBuffer)
{
m_WorldToLightBuffer.SetData(m_WorldToLightCpuData);
m_AtlasUVRectBuffer.SetData(m_AtlasUVRectCpuData);
m_LightTypeBuffer.SetData(m_LightTypeCpuData);
cmd.SetGlobalBuffer(ShaderProperty.additionalLightsWorldToLightBuffer, m_WorldToLightBuffer);
cmd.SetGlobalBuffer(ShaderProperty.additionalLightsCookieAtlasUVRectBuffer, m_AtlasUVRectBuffer);
cmd.SetGlobalBuffer(ShaderProperty.additionalLightsLightTypeBuffer, m_LightTypeBuffer);
}
else
{
cmd.SetGlobalMatrixArray(ShaderProperty.additionalLightsWorldToLights, m_WorldToLightCpuData);
cmd.SetGlobalVectorArray(ShaderProperty.additionalLightsCookieAtlasUVRects, m_AtlasUVRectCpuData);
cmd.SetGlobalFloatArray(ShaderProperty.additionalLightsLightTypes, m_LightTypeCpuData);
}
cmd.SetGlobalFloatArray(ShaderProperty.additionalLightsCookieEnableBits, m_CookieEnableBitsCpuData.data);
isUploaded = true;
}
public void Clear(CommandBuffer cmd)
{
if (isUploaded)
{
// Set all lights to disabled/invalid state
m_CookieEnableBitsCpuData.Clear();
cmd.SetGlobalFloatArray(ShaderProperty.additionalLightsCookieEnableBits, m_CookieEnableBitsCpuData.data);
isUploaded = false;
}
}
}
// Unity defines directional light UVs over a unit box centered at light.
// i.e. (0, 1) uv == (-0.5, 0.5) world area instead of the (0,1) world area.
static readonly Matrix4x4 s_DirLightProj = Matrix4x4.Ortho(-0.5f, 0.5f, -0.5f, 0.5f, -0.5f, 0.5f);
Texture2DAtlas m_AdditionalLightsCookieAtlas;
LightCookieShaderData m_AdditionalLightsCookieShaderData;
readonly Settings m_Settings;
WorkMemory m_WorkMem;
// Mapping: map[visibleLightIndex] = ShaderDataIndex
// Mostly used by deferred rendering.
int[] m_VisibleLightIndexToShaderDataIndex;
// Parameters for rescaling cookies to fit into the atlas.
const int k_MaxCookieSizeDivisor = 16;
int m_CookieSizeDivisor = 1;
uint m_PrevCookieRequestPixelCount = 0xFFFFFFFF;
internal bool IsKeywordLightCookieEnabled { get; private set; }
public LightCookieManager(ref Settings settings)
{
m_Settings = settings;
m_WorkMem = new WorkMemory();
}
void InitAdditionalLights(int size)
{
if (m_Settings.atlas.useMips && m_Settings.atlas.isPow2)
{
// TODO: MipMaps still have sampling artifacts. FIX FIX
// Supports mip padding for correct filtering at the edges.
m_AdditionalLightsCookieAtlas = new PowerOfTwoTextureAtlas(
m_Settings.atlas.resolution.x,
4,
m_Settings.atlas.format,
FilterMode.Bilinear,
"Universal Light Cookie Pow2 Atlas",
true);
}
else
{
// No mip padding support.
m_AdditionalLightsCookieAtlas = new Texture2DAtlas(
m_Settings.atlas.resolution.x,
m_Settings.atlas.resolution.y,
m_Settings.atlas.format,
FilterMode.Bilinear,
false,
"Universal Light Cookie Atlas",
false); // to support mips, use Pow2Atlas
}
m_AdditionalLightsCookieShaderData = new LightCookieShaderData(size, m_Settings.useStructuredBuffer);
const int mainLightCount = 1;
m_VisibleLightIndexToShaderDataIndex = new int[m_Settings.maxAdditionalLights + mainLightCount];
m_CookieSizeDivisor = 1;
m_PrevCookieRequestPixelCount = 0xFFFFFFFF;
}
public bool isInitialized() => m_AdditionalLightsCookieAtlas != null && m_AdditionalLightsCookieShaderData != null;
/// <summary>
/// Release LightCookieManager resources.
/// </summary>
public void Dispose()
{
m_AdditionalLightsCookieAtlas?.Release();
m_AdditionalLightsCookieShaderData?.Dispose();
}
// -1 on invalid/disabled cookie.
public int GetLightCookieShaderDataIndex(int visibleLightIndex)
{
if (!isInitialized())
return -1;
return m_VisibleLightIndexToShaderDataIndex[visibleLightIndex];
}
public void Setup(ScriptableRenderContext ctx, CommandBuffer cmd, ref LightData lightData)
{
using var profScope = new ProfilingScope(cmd, ProfilingSampler.Get(URPProfileId.LightCookies));
// Main light, 1 directional, bound directly
bool isMainLightAvailable = lightData.mainLightIndex >= 0;
if (isMainLightAvailable)
{
var mainLight = lightData.visibleLights[lightData.mainLightIndex];
isMainLightAvailable = SetupMainLight(cmd, ref mainLight);
}
// Additional lights, N spot and point lights in atlas
bool isAdditionalLightsAvailable = lightData.additionalLightsCount > 0;
if (isAdditionalLightsAvailable)
{
isAdditionalLightsAvailable = SetupAdditionalLights(cmd, ref lightData);
}
// Ensure cookies are disabled if no cookies are available.
if (!isAdditionalLightsAvailable)
{
// ..on the CPU (for deferred)
if (m_VisibleLightIndexToShaderDataIndex != null &&
m_AdditionalLightsCookieShaderData.isUploaded)
{
int len = Math.Min(m_VisibleLightIndexToShaderDataIndex.Length, lightData.visibleLights.Length);
for (int i = 0; i < len; i++)
m_VisibleLightIndexToShaderDataIndex[i] = -1;
}
// ..on the GPU
m_AdditionalLightsCookieShaderData?.Clear(cmd);
}
// Main and additional lights are merged into one keyword to reduce variants.
IsKeywordLightCookieEnabled = isMainLightAvailable || isAdditionalLightsAvailable;
CoreUtils.SetKeyword(cmd, ShaderKeywordStrings.LightCookies, IsKeywordLightCookieEnabled);
}
bool SetupMainLight(CommandBuffer cmd, ref VisibleLight visibleMainLight)
{
var mainLight = visibleMainLight.light;
var cookieTexture = mainLight.cookie;
bool isMainLightCookieEnabled = cookieTexture != null;
if (isMainLightCookieEnabled)
{
Matrix4x4 cookieUVTransform = Matrix4x4.identity;
float cookieFormat = (float)GetLightCookieShaderFormat(cookieTexture.graphicsFormat);
if (mainLight.TryGetComponent(out UniversalAdditionalLightData additionalLightData))
GetLightUVScaleOffset(ref additionalLightData, ref cookieUVTransform);
Matrix4x4 cookieMatrix = s_DirLightProj * cookieUVTransform *
visibleMainLight.localToWorldMatrix.inverse;
cmd.SetGlobalTexture(ShaderProperty.mainLightTexture, cookieTexture);
cmd.SetGlobalMatrix(ShaderProperty.mainLightWorldToLight, cookieMatrix);
cmd.SetGlobalFloat(ShaderProperty.mainLightCookieTextureFormat, cookieFormat);
}
else
{
// Make sure we erase stale data in case the main light is disabled but cookie system is enabled (for additional lights).
cmd.SetGlobalTexture(ShaderProperty.mainLightTexture, Texture2D.whiteTexture);
cmd.SetGlobalMatrix(ShaderProperty.mainLightWorldToLight, Matrix4x4.identity);
cmd.SetGlobalFloat(ShaderProperty.mainLightCookieTextureFormat, (float)LightCookieShaderFormat.None);
}
return isMainLightCookieEnabled;
}
private LightCookieShaderFormat GetLightCookieShaderFormat(GraphicsFormat cookieFormat)
{
// TODO: convert this to use GraphicsFormatUtility
switch (cookieFormat)
{
default:
return LightCookieShaderFormat.RGB;
// A8, A16 GraphicsFormat does not expose yet.
case (GraphicsFormat)54:
case (GraphicsFormat)55:
return LightCookieShaderFormat.Alpha;
case GraphicsFormat.R8_SRGB:
case GraphicsFormat.R8_UNorm:
case GraphicsFormat.R8_UInt:
case GraphicsFormat.R8_SNorm:
case GraphicsFormat.R8_SInt:
case GraphicsFormat.R16_UNorm:
case GraphicsFormat.R16_UInt:
case GraphicsFormat.R16_SNorm:
case GraphicsFormat.R16_SInt:
case GraphicsFormat.R16_SFloat:
case GraphicsFormat.R32_UInt:
case GraphicsFormat.R32_SInt:
case GraphicsFormat.R32_SFloat:
case GraphicsFormat.R_BC4_SNorm:
case GraphicsFormat.R_BC4_UNorm:
case GraphicsFormat.R_EAC_SNorm:
case GraphicsFormat.R_EAC_UNorm:
return LightCookieShaderFormat.Red;
}
}
private void GetLightUVScaleOffset(ref UniversalAdditionalLightData additionalLightData, ref Matrix4x4 uvTransform)
{
Vector2 uvScale = Vector2.one / additionalLightData.lightCookieSize;
Vector2 uvOffset = additionalLightData.lightCookieOffset;
if (Mathf.Abs(uvScale.x) < half.MinValue)
uvScale.x = Mathf.Sign(uvScale.x) * half.MinValue;
if (Mathf.Abs(uvScale.y) < half.MinValue)
uvScale.y = Mathf.Sign(uvScale.y) * half.MinValue;
uvTransform = Matrix4x4.Scale(new Vector3(uvScale.x, uvScale.y, 1));
uvTransform.SetColumn(3, new Vector4(-uvOffset.x * uvScale.x, -uvOffset.y * uvScale.y, 0, 1));
}
bool SetupAdditionalLights(CommandBuffer cmd, ref LightData lightData)
{
int maxLightCount = Math.Min(m_Settings.maxAdditionalLights, lightData.visibleLights.Length);
m_WorkMem.Resize(maxLightCount);
int validLightCount = FilterAndValidateAdditionalLights(ref lightData, m_WorkMem.lightMappings);
// Early exit if no valid cookie lights
if (validLightCount <= 0)
return false;
// Lazy init GPU resources
if (!isInitialized())
InitAdditionalLights(validLightCount);
// Update Atlas
var validLights = new WorkSlice<LightCookieMapping>(m_WorkMem.lightMappings, validLightCount);
int validUVRectCount = UpdateAdditionalLightsAtlas(cmd, ref validLights, m_WorkMem.uvRects);
// Upload shader data
var validUvRects = new WorkSlice<Vector4>(m_WorkMem.uvRects, validUVRectCount);
UploadAdditionalLights(cmd, ref lightData, ref validLights, ref validUvRects);
bool isAdditionalLightsEnabled = validUvRects.length > 0;
return isAdditionalLightsEnabled;
}
int FilterAndValidateAdditionalLights(ref LightData lightData, LightCookieMapping[] validLightMappings)
{
int skipMainLightIndex = lightData.mainLightIndex;
int lightBufferOffset = 0;
int validLightCount = 0;
// Warn on dropped lights
int maxLights = Math.Min(lightData.visibleLights.Length, validLightMappings.Length);
for (int i = 0; i < maxLights; i++)
{
if (i == skipMainLightIndex)
{
lightBufferOffset -= 1;
continue;
}
Light light = lightData.visibleLights[i].light;
// Skip lights without a cookie texture
if (light.cookie == null)
continue;
// Only spot and point lights are supported.
// Directional lights basically work,
// but would require a lot of constants for the uv transform parameters
// and there are very few use cases for multiple global cookies.
var lightType = lightData.visibleLights[i].lightType;
if (!(lightType == LightType.Spot ||
lightType == LightType.Point))
{
Debug.LogWarning($"Additional {lightType.ToString()} light called '{light.name}' has a light cookie which will not be visible.", light);
continue;
}
Assertions.Assert.IsTrue(i < ushort.MaxValue);
LightCookieMapping lp;
lp.visibleLightIndex = (ushort)i;
lp.lightBufferIndex = (ushort)(i + lightBufferOffset);
lp.light = light;
validLightMappings[validLightCount++] = lp;
}
return validLightCount;
}
int UpdateAdditionalLightsAtlas(CommandBuffer cmd, ref WorkSlice<LightCookieMapping> validLightMappings, Vector4[] textureAtlasUVRects)
{
// Sort in-place by cookie size for better atlas allocation efficiency (and deduplication)
validLightMappings.Sort(LightCookieMapping.s_CompareByCookieSize);
uint cookieRequestPixelCount = ComputeCookieRequestPixelCount(ref validLightMappings);
var atlasSize = m_AdditionalLightsCookieAtlas.AtlasTexture.referenceSize;
float requestAtlasRatio = cookieRequestPixelCount / (float)(atlasSize.x * atlasSize.y);
int cookieSizeDivisorApprox = ApproximateCookieSizeDivisor(requestAtlasRatio);
// Try to recover resolution and scale the cookies back up.
// If the cookies "should fit" and
// If we have less requested pixels than the last time we found the correct divisor (a guard against retrying every frame).
if (cookieSizeDivisorApprox < m_CookieSizeDivisor &&
cookieRequestPixelCount < m_PrevCookieRequestPixelCount)
{
m_AdditionalLightsCookieAtlas.ResetAllocator();
m_CookieSizeDivisor = cookieSizeDivisorApprox;
}
// Get cached atlas uv rectangles.
// If there's new cookies, first try to add at current scaling level.
// (This can result in suboptimal packing & scaling (additions aren't sorted), but reduces rebuilds.)
// If it doesn't fit, scale down and rebuild the atlas until it fits.
int uvRectCount = 0;
while (uvRectCount <= 0)
{
uvRectCount = FetchUVRects(cmd, ref validLightMappings, textureAtlasUVRects, m_CookieSizeDivisor);
if (uvRectCount <= 0)
{
// Uv rect fetching failed, reset and try again.
m_AdditionalLightsCookieAtlas.ResetAllocator();
// Reduce cookie size to approximate value try to rebuild the atlas.
m_CookieSizeDivisor = Mathf.Max(m_CookieSizeDivisor + 1, cookieSizeDivisorApprox);
m_PrevCookieRequestPixelCount = cookieRequestPixelCount;
}
}
return uvRectCount;
}
int FetchUVRects(CommandBuffer cmd, ref WorkSlice<LightCookieMapping> validLightMappings, Vector4[] textureAtlasUVRects, int cookieSizeDivisor)
{
int uvRectCount = 0;
for (int i = 0; i < validLightMappings.length; i++)
{
var lcm = validLightMappings[i];
Light light = lcm.light;
Texture cookie = light.cookie;
// NOTE: Currently we blit directly on addition (on atlas fetch cache miss).
// This can be costly if there are many resize rebuilds (in case "out-of-space", which shouldn't be a common case).
// If rebuilds become a problem, we could try to just allocate and blit only when we have a fully valid allocation.
// It would also make sense to do atlas operations only for unique textures and then reuse the results for similar cookies.
Vector4 uvScaleOffset = Vector4.zero;
if (cookie.dimension == TextureDimension.Cube)
{
Assertions.Assert.IsTrue(light.type == LightType.Point);
uvScaleOffset = FetchCube(cmd, cookie, cookieSizeDivisor);
}
else
{
Assertions.Assert.IsTrue(light.type == LightType.Spot || light.type == LightType.Directional, "Light type needs 2D texture!");
uvScaleOffset = Fetch2D(cmd, cookie, cookieSizeDivisor);
}
bool isCached = uvScaleOffset != Vector4.zero;
if (!isCached)
{
if (cookieSizeDivisor > k_MaxCookieSizeDivisor)
{
Debug.LogWarning($"Light cookies atlas is extremely full! Some of the light cookies were discarded. Increase light cookie atlas space or reduce the amount of unique light cookies.");
// Complete fail, return what we have.
return uvRectCount;
}
// Failed to get uv rect for each cookie, fail and try again.
return 0;
}
// Adjust atlas UVs for OpenGL
if (!SystemInfo.graphicsUVStartsAtTop)
uvScaleOffset.w = 1.0f - uvScaleOffset.w - uvScaleOffset.y;
textureAtlasUVRects[uvRectCount++] = uvScaleOffset;
}
return uvRectCount;
}
uint ComputeCookieRequestPixelCount(ref WorkSlice<LightCookieMapping> validLightMappings)
{
uint requestPixelCount = 0;
int prevCookieID = 0;
for (int i = 0; i < validLightMappings.length; i++)
{
var lcm = validLightMappings[i];
Texture cookie = lcm.light.cookie;
int cookieID = cookie.GetInstanceID();
// Consider only unique textures as atlas request pixels
// NOTE: relies on same cookies being sorted together
// (we need sorting for good atlas packing anyway)
if (cookieID == prevCookieID)
{
continue;
}
prevCookieID = cookieID;
int pixelCookieCount = cookie.width * cookie.height;
requestPixelCount += (uint)pixelCookieCount;
}
return requestPixelCount;
}
int ApproximateCookieSizeDivisor(float requestAtlasRatio)
{
// (Edge / N)^2 == 1/N^2 of area.
// Ratio/N^2 == 1, sqrt(Ratio) == N, for "1:1" ratio.
return (int)Mathf.Max(Mathf.Ceil(Mathf.Sqrt(requestAtlasRatio)), 1);
}
Vector4 Fetch2D(CommandBuffer cmd, Texture cookie, int cookieSizeDivisor = 1)
{
Assertions.Assert.IsTrue(cookie != null);
Assertions.Assert.IsTrue(cookie.dimension == TextureDimension.Tex2D);
Vector4 uvScaleOffset = Vector4.zero;
var scaledWidth = Mathf.Max(cookie.width / cookieSizeDivisor, 4);
var scaledHeight = Mathf.Max(cookie.height / cookieSizeDivisor, 4);
Vector2 scaledCookieSize = new Vector2(scaledWidth, scaledHeight);
bool isCached = m_AdditionalLightsCookieAtlas.IsCached(out uvScaleOffset, cookie);
if (isCached)
{
// Update contents IF required
m_AdditionalLightsCookieAtlas.UpdateTexture(cmd, cookie, ref uvScaleOffset);
}
else
{
m_AdditionalLightsCookieAtlas.AllocateTexture(cmd, ref uvScaleOffset, cookie, scaledWidth, scaledHeight);
}
AdjustUVRect(ref uvScaleOffset, cookie, ref scaledCookieSize);
return uvScaleOffset;
}
Vector4 FetchCube(CommandBuffer cmd, Texture cookie, int cookieSizeDivisor = 1)
{
Assertions.Assert.IsTrue(cookie != null);
Assertions.Assert.IsTrue(cookie.dimension == TextureDimension.Cube);
Vector4 uvScaleOffset = Vector4.zero;
// Scale octahedral projection, so that cube -> oct2D pixel count match better.
int scaledOctCookieSize = Mathf.Max(ComputeOctahedralCookieSize(cookie) / cookieSizeDivisor, 4);
bool isCached = m_AdditionalLightsCookieAtlas.IsCached(out uvScaleOffset, cookie);
if (isCached)
{
// Update contents IF required
m_AdditionalLightsCookieAtlas.UpdateTexture(cmd, cookie, ref uvScaleOffset);
}
else
{
m_AdditionalLightsCookieAtlas.AllocateTexture(cmd, ref uvScaleOffset, cookie, scaledOctCookieSize, scaledOctCookieSize);
}
// Cookie size in the atlas might not match CookieTexture size.
// UVRect adjustment must be done with size in atlas.
var scaledCookieSize = Vector2.one * scaledOctCookieSize;
AdjustUVRect(ref uvScaleOffset, cookie, ref scaledCookieSize);
return uvScaleOffset;
}
int ComputeOctahedralCookieSize(Texture cookie)
{
// Map 6*WxH pixels into 2W*2H pixels, so 4/6 ratio or 66% of cube pixels.
int octCookieSize = Math.Max(cookie.width, cookie.height);
if (m_Settings.atlas.isPow2)
octCookieSize = octCookieSize * Mathf.NextPowerOfTwo((int)m_Settings.cubeOctahedralSizeScale);
else
octCookieSize = (int)(octCookieSize * m_Settings.cubeOctahedralSizeScale + 0.5f);
return octCookieSize;
}
private void AdjustUVRect(ref Vector4 uvScaleOffset, Texture cookie, ref Vector2 cookieSize)
{
if (uvScaleOffset != Vector4.zero)
{
if (m_Settings.atlas.useMips)
{
// Payload texture is inset
var potAtlas = (m_AdditionalLightsCookieAtlas as PowerOfTwoTextureAtlas);
var mipPadding = potAtlas == null ? 1 : potAtlas.mipPadding;
var paddingSize = Vector2.one * (int)Mathf.Pow(2, mipPadding) * 2;
uvScaleOffset = PowerOfTwoTextureAtlas.GetPayloadScaleOffset(cookieSize, paddingSize, uvScaleOffset);
}
else
{
// Shrink by 0.5px to clamp sampling atlas neighbors (no padding)
ShrinkUVRect(ref uvScaleOffset, 0.5f, ref cookieSize);
}
}
}
private void ShrinkUVRect(ref Vector4 uvScaleOffset, float amountPixels, ref Vector2 cookieSize)
{
var shrinkOffset = Vector2.one * amountPixels / cookieSize;
var shrinkScale = (cookieSize - Vector2.one * (amountPixels * 2)) / cookieSize;
uvScaleOffset.z += uvScaleOffset.x * shrinkOffset.x;
uvScaleOffset.w += uvScaleOffset.y * shrinkOffset.y;
uvScaleOffset.x *= shrinkScale.x;
uvScaleOffset.y *= shrinkScale.y;
}
void UploadAdditionalLights(CommandBuffer cmd, ref LightData lightData, ref WorkSlice<LightCookieMapping> validLightMappings, ref WorkSlice<Vector4> validUvRects)
{
Assertions.Assert.IsTrue(m_AdditionalLightsCookieAtlas != null);
Assertions.Assert.IsTrue(m_AdditionalLightsCookieShaderData != null);
cmd.SetGlobalTexture(ShaderProperty.additionalLightsCookieAtlasTexture, m_AdditionalLightsCookieAtlas.AtlasTexture);
cmd.SetGlobalFloat(ShaderProperty.additionalLightsCookieAtlasTextureFormat, (float)GetLightCookieShaderFormat(m_AdditionalLightsCookieAtlas.AtlasTexture.rt.graphicsFormat));
// Resize and clear visible light to shader data mapping
if (m_VisibleLightIndexToShaderDataIndex.Length < lightData.visibleLights.Length)
m_VisibleLightIndexToShaderDataIndex = new int[lightData.visibleLights.Length];
// Clear
int len = Math.Min(m_VisibleLightIndexToShaderDataIndex.Length, lightData.visibleLights.Length);
for (int i = 0; i < len; i++)
m_VisibleLightIndexToShaderDataIndex[i] = -1;
// Resize or init shader data.
m_AdditionalLightsCookieShaderData.Resize(m_Settings.maxAdditionalLights);
var worldToLights = m_AdditionalLightsCookieShaderData.worldToLights;
var cookieEnableBits = m_AdditionalLightsCookieShaderData.cookieEnableBits;
var atlasUVRects = m_AdditionalLightsCookieShaderData.atlasUVRects;
var lightTypes = m_AdditionalLightsCookieShaderData.lightTypes;
// Set all rects to "Invalid" zero area (Vector4.zero), just in case they're accessed.
Array.Clear(atlasUVRects, 0, atlasUVRects.Length);
// Set all cookies disabled
cookieEnableBits.Clear();
// NOTE: technically, we don't need to upload constants again if we knew the lights, atlas (rects) or visible order haven't changed.
// But detecting that, might be as time consuming as just doing the work.
// Fill shader data. Layout should match primary light data for additional lights.
// Currently it's the same as visible lights, but main light(s) dropped.
for (int i = 0; i < validUvRects.length; i++)
{
int visIndex = validLightMappings[i].visibleLightIndex;
int bufIndex = validLightMappings[i].lightBufferIndex;
// Update the mapping
m_VisibleLightIndexToShaderDataIndex[visIndex] = bufIndex;
var visLight = lightData.visibleLights[visIndex];
// Update the (cpu) data
lightTypes[bufIndex] = (int)visLight.lightType;
worldToLights[bufIndex] = visLight.localToWorldMatrix.inverse;
atlasUVRects[bufIndex] = validUvRects[i];
cookieEnableBits[bufIndex] = true;
// Spot projection
if (visLight.lightType == LightType.Spot)
{
// VisibleLight.localToWorldMatrix only contains position & rotation.
// Multiply projection for spot light.
float spotAngle = visLight.spotAngle;
float spotRange = visLight.range;
var perp = Matrix4x4.Perspective(spotAngle, 1, 0.001f, spotRange);
// Cancel embedded camera view axis flip (https://docs.unity3d.com/2021.1/Documentation/ScriptReference/Matrix4x4.Perspective.html)
perp.SetColumn(2, perp.GetColumn(2) * -1);
// world -> light local -> light perspective
worldToLights[bufIndex] = perp * worldToLights[bufIndex];
}
}
// Apply changes and upload to GPU
m_AdditionalLightsCookieShaderData.Upload(cmd);
}
}
}