Adding new glsl interpolation qualifiers

src/OpenGL/compiler/BaseTypes.h

@@ -142,6 +142,16 @@ enum TQualifier : unsigned char
     EvqFragColor,
     EvqFragData,
 
+    // GLSL ES 3.0 vertex output and fragment input
+    EvqSmooth,        // Incomplete qualifier, smooth is the default
+    EvqFlat,          // Incomplete qualifier
+    EvqSmoothOut = EvqSmooth,
+    EvqFlatOut = EvqFlat,
+    EvqCentroidOut,   // Implies smooth
+    EvqSmoothIn,
+    EvqFlatIn,
+    EvqCentroidIn,    // Implies smooth
+
     // end of list
     EvqLast
 };
@@ -192,7 +202,13 @@ inline const char *getQualifierString(TQualifier qualifier)
     case EvqFragCoord:      return "FragCoord";      break;
     case EvqFrontFacing:    return "FrontFacing";    break;
     case EvqFragColor:      return "FragColor";      break;
-    case EvqFragData:       return "FragData";      break;
+    case EvqFragData:       return "FragData";       break;
+    case EvqSmooth:         return "Smooth";         break;
+    case EvqFlat:           return "Flat";           break;
+    case EvqCentroidOut:    return "CentroidOut";    break;
+    case EvqSmoothIn:       return "SmoothIn";       break;
+    case EvqFlatIn:         return "FlatIn";         break;
+    case EvqCentroidIn:     return "CentroidIn";     break;
     default: UNREACHABLE(); return "unknown qualifier";
     }
 }

src/OpenGL/compiler/ParseHelper.cpp

@@ -315,6 +315,9 @@ bool TParseContext::lValueErrorCheck(int line, const char* op, TIntermTyped* nod
     case EvqConstReadOnly:  message = "can't modify a const";        break;
     case EvqAttribute:      message = "can't modify an attribute";   break;
     case EvqUniform:        message = "can't modify a uniform";      break;
+    case EvqSmoothIn:
+    case EvqFlatIn:
+    case EvqCentroidIn:
     case EvqVaryingIn:      message = "can't modify a varying";      break;
     case EvqInput:          message = "can't modify an input";       break;
     case EvqFragCoord:      message = "can't modify gl_FragCoord";   break;
@@ -609,12 +612,27 @@ bool TParseContext::samplerErrorCheck(int line, const TPublicType& pType, const
 
 bool TParseContext::structQualifierErrorCheck(int line, const TPublicType& pType)
 {
-    if ((pType.qualifier == EvqVaryingIn || pType.qualifier == EvqVaryingOut || pType.qualifier == EvqAttribute) &&
-        pType.type == EbtStruct) {
-        error(line, "cannot be used with a structure", getQualifierString(pType.qualifier));
-
-        return true;
-    }
+	switch(pType.qualifier)
+	{
+	case EvqVaryingOut:
+	case EvqSmooth:
+	case EvqFlat:
+	case EvqCentroidOut:
+	case EvqVaryingIn:
+	case EvqSmoothIn:
+	case EvqFlatIn:
+	case EvqCentroidIn:
+	case EvqAttribute:
+		if(pType.type == EbtStruct)
+		{
+			error(line, "cannot be used with a structure", getQualifierString(pType.qualifier));
+
+			return true;
+		}
+		break;
+	default:
+		break;
+	}
 
     if (pType.qualifier != EvqUniform && samplerErrorCheck(line, pType, "samplers must be uniform"))
         return true;
@@ -1381,6 +1399,52 @@ TLayoutQualifier TParseContext::joinLayoutQualifiers(TLayoutQualifier leftQualif
     return joinedQualifier;
 }
 
+
+TPublicType TParseContext::joinInterpolationQualifiers(const TSourceLoc &interpolationLoc, TQualifier interpolationQualifier,
+	const TSourceLoc &storageLoc, TQualifier storageQualifier)
+{
+	TQualifier mergedQualifier = EvqSmoothIn;
+
+	if(storageQualifier == EvqVaryingIn) {
+		if(interpolationQualifier == EvqSmooth)
+			mergedQualifier = EvqSmoothIn;
+		else if(interpolationQualifier == EvqFlat)
+			mergedQualifier = EvqFlatIn;
+		else UNREACHABLE();
+	}
+	else if(storageQualifier == EvqCentroidIn) {
+		if(interpolationQualifier == EvqSmooth)
+			mergedQualifier = EvqCentroidIn;
+		else if(interpolationQualifier == EvqFlat)
+			mergedQualifier = EvqFlatIn;
+		else UNREACHABLE();
+	}
+	else if(storageQualifier == EvqVaryingOut) {
+		if(interpolationQualifier == EvqSmooth)
+			mergedQualifier = EvqSmoothOut;
+		else if(interpolationQualifier == EvqFlat)
+			mergedQualifier = EvqFlatOut;
+		else UNREACHABLE();
+	}
+	else if(storageQualifier == EvqCentroidOut) {
+		if(interpolationQualifier == EvqSmooth)
+			mergedQualifier = EvqCentroidOut;
+		else if(interpolationQualifier == EvqFlat)
+			mergedQualifier = EvqFlatOut;
+		else UNREACHABLE();
+	}
+	else {
+		error(interpolationLoc, "interpolation qualifier requires a fragment 'in' or vertex 'out' storage qualifier", getQualifierString(interpolationQualifier));
+		recover();
+
+		mergedQualifier = storageQualifier;
+	}
+
+	TPublicType type;
+	type.setBasic(EbtVoid, mergedQualifier, storageLoc);
+	return type;
+}
+
 bool TParseContext::enterStructDeclaration(int line, const TString& identifier)
 {
     ++structNestingLevel;

src/OpenGL/compiler/ParseHelper.h

@@ -127,6 +127,7 @@ struct TParseContext {
     TLayoutQualifier parseLayoutQualifier(const TString &qualifierType, const TSourceLoc& qualifierTypeLine);
     TLayoutQualifier parseLayoutQualifier(const TString &qualifierType, const TSourceLoc& qualifierTypeLine, const TString &intValueString, int intValue, const TSourceLoc& intValueLine);
     TLayoutQualifier joinLayoutQualifiers(TLayoutQualifier leftQualifier, TLayoutQualifier rightQualifier);
+    TPublicType joinInterpolationQualifiers(const TSourceLoc &interpolationLoc, TQualifier interpolationQualifier, const TSourceLoc &storageLoc, TQualifier storageQualifier);
 
     // Performs an error check for embedded struct declarations.
     // Returns true if an error was raised due to the declaration of

src/OpenGL/compiler/glslang.y

@@ -173,7 +173,7 @@ extern void yyerror(TParseContext* context, const char* reason);
 %type <interm.layoutQualifier> layout_qualifier layout_qualifier_id_list layout_qualifier_id
 
 %type <interm.precision> precision_qualifier
-%type <interm.type> type_qualifier fully_specified_type type_specifier storage_qualifier
+%type <interm.type> type_qualifier fully_specified_type type_specifier storage_qualifier interpolation_qualifier
 %type <interm.type> type_specifier_no_prec type_specifier_nonarray
 %type <interm.type> struct_specifier
 %type <interm.typeLine> struct_declarator
@@ -1514,6 +1514,15 @@ fully_specified_type
     }
     ;
 
+interpolation_qualifier
+    : SMOOTH {
+        $$.qualifier = EvqSmooth;
+    }
+    | FLAT {
+        $$.qualifier = EvqFlat;
+    }
+    ;
+
 parameter_type_qualifier
     : CONST_QUAL {
         $$ = EvqConstReadOnly;
@@ -1549,6 +1558,16 @@ type_qualifier
 	| storage_qualifier {
         $$.setBasic(EbtVoid, $1.qualifier, $1.line);
     }
+	| interpolation_qualifier storage_qualifier {
+        $$ = context->joinInterpolationQualifiers($1.line, $1.qualifier, $2.line, $2.qualifier);
+    }
+    | interpolation_qualifier {
+        context->error($1.line, "interpolation qualifier requires a fragment 'in' or vertex 'out' storage qualifier", getQualifierString($1.qualifier));
+        context->recover();
+        
+        TQualifier qual = context->symbolTable.atGlobalLevel() ? EvqGlobal : EvqTemporary;
+        $$.setBasic(EbtVoid, qual, $1.line);
+    }
 	| layout_qualifier {
         $$.qualifier = context->symbolTable.atGlobalLevel() ? EvqGlobal : EvqTemporary;
         $$.layoutQualifier = $1;