Implement scalar `reflect` intrinsic in Metal.
Change-Id: I954af70f545a2258babd82af0d43d509201fdc59
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/348889
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/src/sksl/SkSLMetalCodeGenerator.cpp b/src/sksl/SkSLMetalCodeGenerator.cpp
index 0eb047f..d694716 100644
--- a/src/sksl/SkSLMetalCodeGenerator.cpp
+++ b/src/sksl/SkSLMetalCodeGenerator.cpp
@@ -56,6 +56,7 @@
fIntrinsicMap[String("mod")] = SPECIAL(Mod);
fIntrinsicMap[String("normalize")] = SPECIAL(Normalize);
fIntrinsicMap[String("radians")] = SPECIAL(Radians);
+ fIntrinsicMap[String("reflect")] = SPECIAL(Reflect);
fIntrinsicMap[String("sample")] = SPECIAL(Texture);
fIntrinsicMap[String("equal")] = METAL(Equal);
fIntrinsicMap[String("notEqual")] = METAL(NotEqual);
@@ -582,7 +583,20 @@
return tempVar;
}
-void MetalCodeGenerator::writeSpecialIntrinsic(const FunctionCall & c, SpecialIntrinsic kind) {
+void MetalCodeGenerator::writeSimpleIntrinsic(const FunctionCall& c) {
+ // Write out an intrinsic function call exactly as-is. No muss no fuss.
+ this->write(c.function().name());
+ this->write("(");
+ const char* separator = "";
+ for (const std::unique_ptr<Expression>& arg : c.arguments()) {
+ this->write(separator);
+ separator = ", ";
+ this->writeExpression(*arg, kSequence_Precedence);
+ }
+ this->write(")");
+}
+
+void MetalCodeGenerator::writeSpecialIntrinsic(const FunctionCall& c, SpecialIntrinsic kind) {
const ExpressionArray& arguments = c.arguments();
switch (kind) {
case kTexture_SpecialIntrinsic: {
@@ -625,11 +639,7 @@
this->writeExpression(*arguments[1], kAdditive_Precedence);
this->write(")");
} else {
- this->write("distance(");
- this->writeExpression(*arguments[0], kSequence_Precedence);
- this->write(", ");
- this->writeExpression(*arguments[1], kSequence_Precedence);
- this->write(")");
+ this->writeSimpleIntrinsic(c);
}
break;
}
@@ -641,11 +651,7 @@
this->writeExpression(*arguments[1], kMultiplicative_Precedence);
this->write(")");
} else {
- this->write("dot(");
- this->writeExpression(*arguments[0], kSequence_Precedence);
- this->write(", ");
- this->writeExpression(*arguments[1], kSequence_Precedence);
- this->write(")");
+ this->writeSimpleIntrinsic(c);
}
break;
}
@@ -660,13 +666,7 @@
this->writeExpression(*arguments[0], kSequence_Precedence);
this->write("))");
} else {
- this->write("faceforward(");
- this->writeExpression(*arguments[0], kSequence_Precedence);
- this->write(", ");
- this->writeExpression(*arguments[1], kSequence_Precedence);
- this->write(", ");
- this->writeExpression(*arguments[2], kSequence_Precedence);
- this->write(")");
+ this->writeSimpleIntrinsic(c);
}
break;
}
@@ -701,6 +701,27 @@
this->write(") * 0.0174532925)");
break;
}
+ case kReflect_SpecialIntrinsic: {
+ if (arguments[0]->type().columns() == 1) {
+ // We need to synthesize `I - 2 * N * I * N`.
+ String tmpI = this->getTempVariable(arguments[0]->type());
+ String tmpN = this->getTempVariable(arguments[1]->type());
+
+ // (_skTempI = ...
+ this->write("(" + tmpI + " = ");
+ this->writeExpression(*arguments[0], kSequence_Precedence);
+
+ // , _skTempN = ...
+ this->write(", " + tmpN + " = ");
+ this->writeExpression(*arguments[1], kSequence_Precedence);
+
+ // , _skTempI - 2 * _skTempN * _skTempI * _skTempN)
+ this->write(", " + tmpI + " - 2 * " + tmpN + " * " + tmpI + " * " + tmpN + ")");
+ } else {
+ this->writeSimpleIntrinsic(c);
+ }
+ break;
+ }
case kBitCount_SpecialIntrinsic: {
this->write("popcount(");
this->writeExpression(*arguments[0], kSequence_Precedence);
diff --git a/src/sksl/SkSLMetalCodeGenerator.h b/src/sksl/SkSLMetalCodeGenerator.h
index ca5f3bd..96b55c7 100644
--- a/src/sksl/SkSLMetalCodeGenerator.h
+++ b/src/sksl/SkSLMetalCodeGenerator.h
@@ -115,6 +115,7 @@
kMod_SpecialIntrinsic,
kNormalize_SpecialIntrinsic,
kRadians_SpecialIntrinsic,
+ kReflect_SpecialIntrinsic,
kTexture_SpecialIntrinsic,
};
@@ -235,6 +236,8 @@
void writeMatrixCompMult();
void writeMatrixTimesEqualHelper(const Type& left, const Type& right, const Type& result);
+ void writeSimpleIntrinsic(const FunctionCall& c);
+
void writeSpecialIntrinsic(const FunctionCall& c, SpecialIntrinsic kind);
bool canCoerce(const Type& t1, const Type& t2);
diff --git a/tests/sksl/intrinsics/golden/Reflect.metal b/tests/sksl/intrinsics/golden/Reflect.metal
index 290ccb1..664eacf 100644
--- a/tests/sksl/intrinsics/golden/Reflect.metal
+++ b/tests/sksl/intrinsics/golden/Reflect.metal
@@ -17,7 +17,9 @@
fragment Outputs fragmentMain(Inputs _in [[stage_in]], bool _frontFacing [[front_facing]], float4 _fragCoord [[position]]) {
Outputs _outputStruct;
thread Outputs* _out = &_outputStruct;
- _out->sk_FragColor.x = reflect(_in.a, _in.b);
+ float _skTemp0;
+ float _skTemp1;
+ _out->sk_FragColor.x = (_skTemp0 = _in.a, _skTemp1 = _in.b, _skTemp0 - 2 * _skTemp1 * _skTemp0 * _skTemp1);
_out->sk_FragColor = reflect(_in.c, _in.d);
return *_out;
}
