private static void ApplyScalingNoInterpolation(CodeGenContext context, SpvInstruction output, SpvInstruction vector, SpvInstruction scale)
{
if (context.Config.Stage == ShaderStage.Vertex)
{
scale = context.GlslFAbs(context.TypeFP32(), scale);
}
var vector2Type = context.TypeVector(context.TypeFP32(), 2);
var vectorFloat = context.ConvertSToF(vector2Type, vector);
var vectorScaled = context.VectorTimesScalar(vector2Type, vectorFloat, scale);
context.Store(output, context.ConvertFToS(context.TypeVector(context.TypeS32(), 2), vectorScaled));
}
private static void ApplyScalingInterpolated(CodeGenContext context, SpvInstruction output, SpvInstruction vector, SpvInstruction scale)
{
var vector2Type = context.TypeVector(context.TypeFP32(), 2);
var scaleNegated = context.FNegate(context.TypeFP32(), scale);
var scaleVector = context.CompositeConstruct(vector2Type, scaleNegated, scaleNegated);
var vectorFloat = context.ConvertSToF(vector2Type, vector);
var vectorScaled = context.VectorTimesScalar(vector2Type, vectorFloat, scaleNegated);
var fragCoordPointer = context.Inputs[AttributeConsts.PositionX];
var fragCoord = context.Load(context.TypeVector(context.TypeFP32(), 4), fragCoordPointer);
var fragCoordXY = context.VectorShuffle(vector2Type, fragCoord, fragCoord, 0, 1);
var scaleMod = context.FMod(vector2Type, fragCoordXY, scaleVector);
var vectorInterpolated = context.FAdd(vector2Type, vectorScaled, scaleMod);
context.Store(output, context.ConvertFToS(context.TypeVector(context.TypeS32(), 2), vectorInterpolated));
}
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);
}
}
}
private static SpvInstruction ApplyScaling2D(CodeGenContext context, SpvInstruction vector, int index)
{
var pointerType = context.TypePointer(StorageClass.Uniform, context.TypeFP32());
var fieldIndex = context.Constant(context.TypeU32(), 4);
var scaleIndex = context.Constant(context.TypeU32(), index);
if (context.Config.Stage == ShaderStage.Vertex)
{
var scaleCountPointerType = context.TypePointer(StorageClass.Uniform, context.TypeS32());
var scaleCountElemPointer = context.AccessChain(scaleCountPointerType, context.SupportBuffer, context.Constant(context.TypeU32(), 3));
var scaleCount = context.Load(context.TypeS32(), scaleCountElemPointer);
scaleIndex = context.IAdd(context.TypeU32(), scaleIndex, scaleCount);
}
scaleIndex = context.IAdd(context.TypeU32(), scaleIndex, context.Constant(context.TypeU32(), 1));
var scaleElemPointer = context.AccessChain(pointerType, context.SupportBuffer, fieldIndex, scaleIndex);
var scale = context.Load(context.TypeFP32(), scaleElemPointer);
var ivector2Type = context.TypeVector(context.TypeS32(), 2);
var localVector = context.CoordTemp;
var passthrough = context.FOrdEqual(context.TypeBool(), scale, context.Constant(context.TypeFP32(), 1f));
var mergeLabel = context.Label();
if (context.Config.Stage == ShaderStage.Fragment)
{
var scaledInterpolatedLabel = context.Label();
var scaledNoInterpolationLabel = context.Label();
var needsInterpolation = context.FOrdLessThan(context.TypeBool(), scale, context.Constant(context.TypeFP32(), 0f));
context.SelectionMerge(mergeLabel, SelectionControlMask.MaskNone);
context.BranchConditional(needsInterpolation, scaledInterpolatedLabel, scaledNoInterpolationLabel);
// scale < 0.0
context.AddLabel(scaledInterpolatedLabel);
ApplyScalingInterpolated(context, localVector, vector, scale);
context.Branch(mergeLabel);
// scale >= 0.0
context.AddLabel(scaledNoInterpolationLabel);
ApplyScalingNoInterpolation(context, localVector, vector, scale);
context.Branch(mergeLabel);
context.AddLabel(mergeLabel);
var passthroughLabel = context.Label();
var finalMergeLabel = context.Label();
context.SelectionMerge(finalMergeLabel, SelectionControlMask.MaskNone);
context.BranchConditional(passthrough, passthroughLabel, finalMergeLabel);
context.AddLabel(passthroughLabel);
context.Store(localVector, vector);
context.Branch(finalMergeLabel);
context.AddLabel(finalMergeLabel);
return(context.Load(ivector2Type, localVector));
}
else
{
var passthroughLabel = context.Label();
var scaledLabel = context.Label();
context.SelectionMerge(mergeLabel, SelectionControlMask.MaskNone);
context.BranchConditional(passthrough, passthroughLabel, scaledLabel);
// scale == 1.0
context.AddLabel(passthroughLabel);
context.Store(localVector, vector);
context.Branch(mergeLabel);
// scale != 1.0
context.AddLabel(scaledLabel);
ApplyScalingNoInterpolation(context, localVector, vector, scale);
context.Branch(mergeLabel);
context.AddLabel(mergeLabel);
return(context.Load(ivector2Type, localVector));
}
}
