private static void Generate(CodeGenContext context, StructuredProgramInfo info, int funcIndex)
{
var function = info.Functions[funcIndex];
(_, var spvFunc) = context.GetFunction(funcIndex);
context.AddFunction(spvFunc);
context.StartFunction();
Declarations.DeclareParameters(context, function);
context.EnterBlock(function.MainBlock);
Declarations.DeclareLocals(context, function);
Declarations.DeclareLocalForArgs(context, info.Functions);
if (funcIndex == 0)
{
var v4Type = context.TypeVector(context.TypeFP32(), 4);
var zero = context.Constant(context.TypeFP32(), 0f);
var one = context.Constant(context.TypeFP32(), 1f);
// Some games will leave some elements of gl_Position uninitialized,
// in those cases, the elements will contain undefined values according
// to the spec, but on NVIDIA they seems to be always initialized to (0, 0, 0, 1),
// so we do explicit initialization to avoid UB on non-NVIDIA gpus.
if (context.Config.Stage == ShaderStage.Vertex)
{
var elemPointer = context.GetAttributeVectorPointer(new AstOperand(OperandType.Attribute, AttributeConsts.PositionX), true);
context.Store(elemPointer, context.CompositeConstruct(v4Type, zero, zero, zero, one));
}
// Ensure that unused attributes are set, otherwise the downstream
// compiler may eliminate them.
// (Not needed for fragment shader as it is the last stage).
if (context.Config.Stage != ShaderStage.Compute &&
context.Config.Stage != ShaderStage.Fragment &&
!context.Config.GpPassthrough)
{
for (int attr = 0; attr < Declarations.MaxAttributes; attr++)
{
if (info.Outputs.Contains(attr))
{
continue;
}
if (context.Config.Options.Flags.HasFlag(TranslationFlags.Feedback))
{
throw new NotImplementedException();
}
else
{
int currAttr = AttributeConsts.UserAttributeBase + attr * 16;
var elemPointer = context.GetAttributeVectorPointer(new AstOperand(OperandType.Attribute, currAttr), true);
context.Store(elemPointer, context.CompositeConstruct(v4Type, zero, zero, zero, one));
}
}
}
}
Generate(context, function.MainBlock);
context.FunctionEnd();
if (funcIndex == 0)
{
context.AddEntryPoint(context.Config.Stage.Convert(), spvFunc, "main", context.GetMainInterface());
if (context.Config.Stage == ShaderStage.Fragment)
{
context.AddExecutionMode(spvFunc, context.Config.Options.TargetApi == TargetApi.Vulkan
? ExecutionMode.OriginUpperLeft
: ExecutionMode.OriginLowerLeft);
}
else if (context.Config.Stage == ShaderStage.Compute)
{
var localSizeX = (SpvLiteralInteger)context.Config.GpuAccessor.QueryComputeLocalSizeX();
var localSizeY = (SpvLiteralInteger)context.Config.GpuAccessor.QueryComputeLocalSizeY();
var localSizeZ = (SpvLiteralInteger)context.Config.GpuAccessor.QueryComputeLocalSizeZ();
context.AddExecutionMode(
spvFunc,
ExecutionMode.LocalSize,
localSizeX,
localSizeY,
localSizeZ);
}
}
}
