public static ShaderCacheFile GetOrCreateCachedShaders(
ResourceFactory factory,
Assembly shaderAssembly,
string shaderName)
{
const string shaderCacheFolder = "ShaderCache";
var backendType = factory.BackendType;
var targetExtension = backendType.ToString().ToLowerInvariant();
if (!Directory.Exists(shaderCacheFolder))
{
Directory.CreateDirectory(shaderCacheFolder);
}
var vsSpvBytes = ReadShaderSpv(shaderAssembly, shaderName, "vert");
var fsSpvBytes = ReadShaderSpv(shaderAssembly, shaderName, "frag");
var spvHash = GetShaderHash(vsSpvBytes, fsSpvBytes);
// Look for cached shader file on disk match the input SPIR-V shaders.
var cacheFilePath = Path.Combine(shaderCacheFolder, $"OpenSage.Assets.Shaders.{shaderName}.{spvHash}.{targetExtension}");
if (ShaderCacheFile.TryLoad(cacheFilePath, out var shaderCacheFile))
{
// Cache is valid - use it.
return(shaderCacheFile);
}
// Cache is invalid or doesn't exist - do cross-compilation.
// For Vulkan, we don't actually need to do cross-compilation. But we do need to get reflection data.
// So we cross-compile to HLSL, throw away the resulting HLSL, and use the reflection data.
var compilationTarget = backendType == GraphicsBackend.Vulkan
? CrossCompileTarget.HLSL
: GetCompilationTarget(backendType);
var compilationResult = SpirvCompilation.CompileVertexFragment(
vsSpvBytes,
fsSpvBytes,
compilationTarget,
new CrossCompileOptions());
byte[] vsBytes, fsBytes;
switch (backendType)
{
case GraphicsBackend.Vulkan:
vsBytes = vsSpvBytes;
fsBytes = fsSpvBytes;
break;
case GraphicsBackend.Direct3D11:
vsBytes = CompileHlsl(compilationResult.VertexShader, "vs_5_0");
fsBytes = CompileHlsl(compilationResult.FragmentShader, "ps_5_0");
break;
case GraphicsBackend.OpenGL:
case GraphicsBackend.OpenGLES:
vsBytes = Encoding.ASCII.GetBytes(compilationResult.VertexShader);
fsBytes = Encoding.ASCII.GetBytes(compilationResult.FragmentShader);
break;
case GraphicsBackend.Metal:
// TODO: Compile to IR.
vsBytes = Encoding.UTF8.GetBytes(compilationResult.VertexShader);
fsBytes = Encoding.UTF8.GetBytes(compilationResult.FragmentShader);
break;
default:
throw new InvalidOperationException();
}
var entryPoint = factory.BackendType == GraphicsBackend.Metal
? $"{EntryPoint}0"
: EntryPoint;
shaderCacheFile = new ShaderCacheFile(
new ShaderDescription(ShaderStages.Vertex, vsBytes, entryPoint),
new ShaderDescription(ShaderStages.Fragment, fsBytes, entryPoint),
compilationResult.Reflection.ResourceLayouts);
shaderCacheFile.Save(cacheFilePath);
return(shaderCacheFile);
}
public static bool TryLoad(string filePath, out ShaderCacheFile result)
{
if (!File.Exists(filePath))
{
result = null;
return(false);
}
using var fileStream = File.OpenRead(filePath);
using var binaryReader = new BinaryReader(fileStream);
var version = binaryReader.ReadInt32();
if (version != Version)
{
result = null;
return(false);
}
var vsEntryPoint = binaryReader.ReadString();
var vsBytesLength = binaryReader.ReadInt32();
var vsBytes = new byte[vsBytesLength];
for (var i = 0; i < vsBytesLength; i++)
{
vsBytes[i] = binaryReader.ReadByte();
}
var fsEntryPoint = binaryReader.ReadString();
var fsBytesLength = binaryReader.ReadInt32();
var fsBytes = new byte[fsBytesLength];
for (var i = 0; i < fsBytesLength; i++)
{
fsBytes[i] = binaryReader.ReadByte();
}
var numResourceLayoutDescriptions = binaryReader.ReadInt32();
var resourceLayoutDescriptions = new ResourceLayoutDescription[numResourceLayoutDescriptions];
for (var i = 0; i < numResourceLayoutDescriptions; i++)
{
var numElements = binaryReader.ReadInt32();
resourceLayoutDescriptions[i] = new ResourceLayoutDescription
{
Elements = new ResourceLayoutElementDescription[numElements]
};
for (var j = 0; j < numElements; j++)
{
resourceLayoutDescriptions[i].Elements[j] = new ResourceLayoutElementDescription
{
Name = binaryReader.ReadString(),
Kind = (ResourceKind)binaryReader.ReadByte(),
Stages = (ShaderStages)binaryReader.ReadByte(),
Options = (ResourceLayoutElementOptions)binaryReader.ReadByte(),
};
}
}
result = new ShaderCacheFile(
new ShaderDescription(ShaderStages.Vertex, vsBytes, vsEntryPoint),
new ShaderDescription(ShaderStages.Fragment, fsBytes, fsEntryPoint),
resourceLayoutDescriptions);
return(true);
}
