/// <summary>
/// Generate ShaderObject source.
/// </summary>
/// <param name="ctx">
/// A <see cref="GraphicsContext"/> used for the compilation process.
/// </param>
/// <param name="cctx">
/// A <see cref="ShaderCompilerContext"/> that specify the information required for compiling this ShaderObject.
/// </param>
/// <returns>
/// It returns a <see cref="List{T}"/> which represent this ShaderObject source. This source text is ready to be compiled.
/// </returns>
private List <string> GenerateSource(GraphicsContext ctx, ShaderCompilerContext cctx)
{
if (ctx == null)
{
throw new ArgumentNullException("ctx");
}
if (cctx == null)
{
throw new ArgumentNullException("cctx");
}
if (_SourceStrings == null)
{
throw new InvalidOperationException("no source loaded");
}
List <string> shaderSource = new List <string>(256);
string[] shaderSourceStrings = _SourceStrings.ToArray();
// Append imposed header - Every source shall compile with this header
AppendHeader(ctx, cctx, shaderSource, cctx.ShaderVersion.VersionId);
// Append required #define statments
if (cctx.Defines != null)
{
foreach (string def in cctx.Defines)
{
shaderSource.Add(String.Format("#define {0} 1\n", def));
Log(" Symbol: {0}", def);
}
}
// Append specific source for composing shader essence
AppendSourceStrings(shaderSource, shaderSourceStrings);
// Remove comment lines
shaderSource = CleanSource(shaderSource);
// Preprocessing
// Manage #include preprocessor directives in the case GL_ARB_shading_language_include is not supported
// When #include are replaced, conditionals are processed too
if (ctx.Extensions.ShadingLanguageInclude_ARB == false)
{
shaderSource = ShaderPreprocessor.Process(shaderSource, cctx, ctx.IncludeLibrary, ShaderPreprocessor.Stage.All);
}
shaderSource = CleanSource(shaderSource);
return(shaderSource);
}
/// <summary>
/// Generate Shader source.
/// </summary>
/// <param name="ctx">
/// A <see cref="GraphicsContext"/> used for the compilation process.
/// </param>
/// <param name="cctx">
/// A <see cref="ShaderCompilerContext"/> that specify the information required for compiling this Shader.
/// </param>
/// <returns>
/// It returns a <see cref="List{T}"/> which represent this Shader source. This source text is ready to be compiled.
/// </returns>
private List <string> GenerateSource(GraphicsContext ctx, ShaderCompilerContext cctx)
{
if (ctx == null)
{
throw new ArgumentNullException("ctx");
}
if (cctx == null)
{
throw new ArgumentNullException("cctx");
}
if (_SourceStrings == null)
{
throw new InvalidOperationException("no source loaded");
}
List <string> sourceLines = new List <string>();
// Initial status: original
AppendSourceStrings(sourceLines, _SourceStrings.ToArray());
// Append imposed header - Every source shall compile with this header
int headerLine = 0;
if (ctx.ShadingVersion.Api == KhronosVersion.ApiGlsl)
{
// Automatically prepend required shader version, if necessary
if (sourceLines.Count > 0 && !Regex.IsMatch(sourceLines[0], @"\s*#version \d+.*"))
{
int version = cctx.ShaderVersion.VersionId;
if (version >= 150)
{
// Starting from GLSL 1.50, profiles are implemented
if ((ctx.Flags & GraphicsContextFlags.ForwardCompatible) != 0)
{
sourceLines.Insert(headerLine++, $"#version {version} core\n");
}
else
{
sourceLines.Insert(headerLine++, $"#version {version} compatibility\n");
}
}
else
{
sourceLines.Insert(headerLine++, $"#version {version}\n");
}
}
else
{
headerLine++; // #version already specified by implementor
}
// #extension
if (ctx.Extensions.ShadingLanguageInclude_ARB)
{
sourceLines.Insert(headerLine++, "#extension GL_ARB_shading_language_include : require\n");
}
if (ctx.Extensions.UniformBufferObject_ARB)
{
sourceLines.Insert(headerLine++, "#extension GL_ARB_uniform_buffer_object : enable\n");
}
else
{
sourceLines.Insert(headerLine++, "#define DISABLE_GL_ARB_uniform_buffer_object\n");
}
if (ObjectStage == ShaderType.GeometryShader && ctx.Extensions.GeometryShader4_ARB)
{
sourceLines.Insert(headerLine++, "#extension GL_ARB_geometry_shader4 : enable\n");
}
if (ctx.Extensions.ShaderDrawParameters_ARB)
{
sourceLines.Insert(headerLine++, "#extension GL_ARB_shader_draw_parameters : enable\n");
}
foreach (ShaderExtension shaderExtension in cctx.Extensions)
{
// Do not include any #extension directive on extensions not supported by driver
if (ctx.Extensions.HasExtensions(shaderExtension.Name) == false)
{
continue;
}
sourceLines.Insert(headerLine++, $"#extension {shaderExtension.Name} : {shaderExtension.Behavior.ToString().ToLowerInvariant()}\n");
}
// #pragma
#if DEBUG
// Debug directives
sourceLines.Insert(headerLine++, "#pragma optimization(off)\n");
sourceLines.Insert(headerLine++, "#pragma debug(on)\n");
#else
sourceLines.Insert(headerLine++, "#pragma optimization(on)\n");
sourceLines.Insert(headerLine++, "#pragma debug(off)\n");
#endif
}
else
{
switch (ObjectStage)
{
case ShaderType.FragmentShader:
sourceLines.Insert(headerLine++, "precision mediump float;\n");
break;
}
}
// Append required #define statments
if (cctx.Defines != null)
{
foreach (string def in cctx.Defines)
{
sourceLines.Insert(headerLine++, $"#define {def} 1\n");
Log(" Symbol: {0}", def);
}
}
// Remove comment lines
sourceLines = CleanSource(sourceLines);
// Preprocessing
// Manage #include preprocessor directives in the case GL_ARB_shading_language_include is not supported
// When #include are replaced, conditionals are processed too
if (!ctx.Extensions.ShadingLanguageInclude_ARB)
{
sourceLines = ShaderPreprocessor.Process(sourceLines, cctx, ctx.IncludeLibrary, ShaderPreprocessor.Stage.All);
sourceLines = CleanSource(sourceLines);
}
return(sourceLines);
}