internal/shader: allow integer types for abs and sign

Updates #2788

internal/shader/expr.go

@@ -537,19 +537,37 @@ func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, mar
 					cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 1 but %d", callee.BuiltinFunc, len(args)))
 					return nil, nil, nil, false
 				}
+
+				if args[0].Const != nil && argts[0].Main == shaderir.None {
+					switch callee.BuiltinFunc {
+					case shaderir.Abs, shaderir.Sign:
+						if args[0].Const.Kind() == gconstant.Int {
+							argts[0] = shaderir.Type{Main: shaderir.Int}
+						}
+						if args[0].Const.Kind() == gconstant.Float {
+							argts[0] = shaderir.Type{Main: shaderir.Float}
+						}
+					default:
 						// If the argument is a non-typed constant value, treat this as a float value (#1874).
-				if args[0].Const != nil && argts[0].Main == shaderir.None && gconstant.ToFloat(args[0].Const).Kind() != gconstant.Unknown {
+						if gconstant.ToFloat(args[0].Const).Kind() != gconstant.Unknown {
 							args[0].Const = gconstant.ToFloat(args[0].Const)
 							argts[0] = shaderir.Type{Main: shaderir.Float}
 						}
+					}
+				}
 				switch callee.BuiltinFunc {
 				case shaderir.Transpose:
-					if argts[0].Main != shaderir.Mat2 && argts[0].Main != shaderir.Mat3 && argts[0].Main != shaderir.Mat4 {
+					if !argts[0].IsMatrix() {
 						cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as mat2, mat3, or mat4 value in argument to %s", argts[0].String(), callee.BuiltinFunc))
 						return nil, nil, nil, false
 					}
+				case shaderir.Abs, shaderir.Sign:
+					if argts[0].Main != shaderir.Float && !argts[0].IsFloatVector() && argts[0].Main != shaderir.Int && !argts[0].IsIntVector() {
+						cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vecN, int, or ivenN value in argument to %s", argts[0].String(), callee.BuiltinFunc))
+						return nil, nil, nil, false
+					}
 				default:
-					if argts[0].Main != shaderir.Float && argts[0].Main != shaderir.Vec2 && argts[0].Main != shaderir.Vec3 && argts[0].Main != shaderir.Vec4 {
+					if argts[0].Main != shaderir.Float && !argts[0].IsFloatVector() {
 						cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vec2, vec3, or vec4 value in argument to %s", argts[0].String(), callee.BuiltinFunc))
 						return nil, nil, nil, false
 					}

internal/shader/syntax_test.go

@@ -2103,8 +2103,6 @@ func TestSyntaxBuiltinFuncSingleArgType(t *testing.T) {
 		"log2",
 		"sqrt",
 		"inversesqrt",
-		"abs",
-		"sign",
 		"floor",
 		"ceil",
 		"fract",
@@ -2133,6 +2131,51 @@ func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	}
 }
 
+func TestSyntaxBuiltinFuncSingleArgTypeInteger(t *testing.T) {
+	cases := []struct {
+		stmt string
+		err  bool
+	}{
+		{stmt: "a := {{.Func}}(); _ = a", err: true},
+		{stmt: "a := {{.Func}}(false); _ = a", err: true},
+		{stmt: "a := {{.Func}}(1); _ = a", err: false},
+		{stmt: "a := {{.Func}}(1.0); _ = a", err: false},
+		{stmt: "a := {{.Func}}(int(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(vec2(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(vec3(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(vec4(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(ivec2(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(ivec3(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(ivec4(1)); _ = a", err: false},
+		{stmt: "a := {{.Func}}(mat2(1)); _ = a", err: true},
+		{stmt: "a := {{.Func}}(mat3(1)); _ = a", err: true},
+		{stmt: "a := {{.Func}}(mat4(1)); _ = a", err: true},
+		{stmt: "a := {{.Func}}(1, 1); _ = a", err: true},
+	}
+
+	funcs := []string{
+		"abs",
+		"sign",
+	}
+	for _, c := range cases {
+		for _, f := range funcs {
+			stmt := strings.ReplaceAll(c.stmt, "{{.Func}}", f)
+			src := fmt.Sprintf(`package main
+
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
+	%s
+	return dstPos
+}`, stmt)
+			_, err := compileToIR([]byte(src))
+			if err == nil && c.err {
+				t.Errorf("%s must return an error but does not", stmt)
+			} else if err != nil && !c.err {
+				t.Errorf("%s must not return nil but returned %v", stmt, err)
+			}
+		}
+	}
+}
+
 // Issue #2184
 func TestSyntaxBuiltinFuncDoubleArgsType(t *testing.T) {
 	cases := []struct {